FFmpeg
avcodec.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
23 
24 /**
25  * @file
26  * @ingroup libavc
27  * Libavcodec external API header
28  */
29 
30 #include <errno.h>
31 #include "libavutil/samplefmt.h"
32 #include "libavutil/attributes.h"
33 #include "libavutil/avutil.h"
34 #include "libavutil/buffer.h"
35 #include "libavutil/cpu.h"
36 #include "libavutil/channel_layout.h"
37 #include "libavutil/dict.h"
38 #include "libavutil/frame.h"
39 #include "libavutil/hwcontext.h"
40 #include "libavutil/log.h"
41 #include "libavutil/pixfmt.h"
42 #include "libavutil/rational.h"
43 
44 #include "version.h"
45 
46 /**
47  * @defgroup libavc libavcodec
48  * Encoding/Decoding Library
49  *
50  * @{
51  *
52  * @defgroup lavc_decoding Decoding
53  * @{
54  * @}
55  *
56  * @defgroup lavc_encoding Encoding
57  * @{
58  * @}
59  *
60  * @defgroup lavc_codec Codecs
61  * @{
62  * @defgroup lavc_codec_native Native Codecs
63  * @{
64  * @}
65  * @defgroup lavc_codec_wrappers External library wrappers
66  * @{
67  * @}
68  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
69  * @{
70  * @}
71  * @}
72  * @defgroup lavc_internal Internal
73  * @{
74  * @}
75  * @}
76  */
77 
78 /**
79  * @ingroup libavc
80  * @defgroup lavc_encdec send/receive encoding and decoding API overview
81  * @{
82  *
83  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
84  * avcodec_receive_packet() functions provide an encode/decode API, which
85  * decouples input and output.
86  *
87  * The API is very similar for encoding/decoding and audio/video, and works as
88  * follows:
89  * - Set up and open the AVCodecContext as usual.
90  * - Send valid input:
91  * - For decoding, call avcodec_send_packet() to give the decoder raw
92  * compressed data in an AVPacket.
93  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
94  * containing uncompressed audio or video.
95  * In both cases, it is recommended that AVPackets and AVFrames are
96  * refcounted, or libavcodec might have to copy the input data. (libavformat
97  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
98  * refcounted AVFrames.)
99  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
100  * functions and process their output:
101  * - For decoding, call avcodec_receive_frame(). On success, it will return
102  * an AVFrame containing uncompressed audio or video data.
103  * - For encoding, call avcodec_receive_packet(). On success, it will return
104  * an AVPacket with a compressed frame.
105  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
106  * AVERROR(EAGAIN) return value means that new input data is required to
107  * return new output. In this case, continue with sending input. For each
108  * input frame/packet, the codec will typically return 1 output frame/packet,
109  * but it can also be 0 or more than 1.
110  *
111  * At the beginning of decoding or encoding, the codec might accept multiple
112  * input frames/packets without returning a frame, until its internal buffers
113  * are filled. This situation is handled transparently if you follow the steps
114  * outlined above.
115  *
116  * In theory, sending input can result in EAGAIN - this should happen only if
117  * not all output was received. You can use this to structure alternative decode
118  * or encode loops other than the one suggested above. For example, you could
119  * try sending new input on each iteration, and try to receive output if that
120  * returns EAGAIN.
121  *
122  * End of stream situations. These require "flushing" (aka draining) the codec,
123  * as the codec might buffer multiple frames or packets internally for
124  * performance or out of necessity (consider B-frames).
125  * This is handled as follows:
126  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
127  * or avcodec_send_frame() (encoding) functions. This will enter draining
128  * mode.
129  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
130  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
131  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
132  * - Before decoding can be resumed again, the codec has to be reset with
133  * avcodec_flush_buffers().
134  *
135  * Using the API as outlined above is highly recommended. But it is also
136  * possible to call functions outside of this rigid schema. For example, you can
137  * call avcodec_send_packet() repeatedly without calling
138  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
139  * until the codec's internal buffer has been filled up (which is typically of
140  * size 1 per output frame, after initial input), and then reject input with
141  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
142  * read at least some output.
143  *
144  * Not all codecs will follow a rigid and predictable dataflow; the only
145  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
146  * one end implies that a receive/send call on the other end will succeed, or
147  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
148  * permit unlimited buffering of input or output.
149  *
150  * This API replaces the following legacy functions:
151  * - avcodec_decode_video2() and avcodec_decode_audio4():
152  * Use avcodec_send_packet() to feed input to the decoder, then use
153  * avcodec_receive_frame() to receive decoded frames after each packet.
154  * Unlike with the old video decoding API, multiple frames might result from
155  * a packet. For audio, splitting the input packet into frames by partially
156  * decoding packets becomes transparent to the API user. You never need to
157  * feed an AVPacket to the API twice (unless it is rejected with AVERROR(EAGAIN) - then
158  * no data was read from the packet).
159  * Additionally, sending a flush/draining packet is required only once.
160  * - avcodec_encode_video2()/avcodec_encode_audio2():
161  * Use avcodec_send_frame() to feed input to the encoder, then use
162  * avcodec_receive_packet() to receive encoded packets.
163  * Providing user-allocated buffers for avcodec_receive_packet() is not
164  * possible.
165  * - The new API does not handle subtitles yet.
166  *
167  * Mixing new and old function calls on the same AVCodecContext is not allowed,
168  * and will result in undefined behavior.
169  *
170  * Some codecs might require using the new API; using the old API will return
171  * an error when calling it. All codecs support the new API.
172  *
173  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
174  * would be an invalid state, which could put the codec user into an endless
175  * loop. The API has no concept of time either: it cannot happen that trying to
176  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
177  * later accepts the packet (with no other receive/flush API calls involved).
178  * The API is a strict state machine, and the passage of time is not supposed
179  * to influence it. Some timing-dependent behavior might still be deemed
180  * acceptable in certain cases. But it must never result in both send/receive
181  * returning EAGAIN at the same time at any point. It must also absolutely be
182  * avoided that the current state is "unstable" and can "flip-flop" between
183  * the send/receive APIs allowing progress. For example, it's not allowed that
184  * the codec randomly decides that it actually wants to consume a packet now
185  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
186  * avcodec_send_packet() call.
187  * @}
188  */
189 
190 /**
191  * @defgroup lavc_core Core functions/structures.
192  * @ingroup libavc
193  *
194  * Basic definitions, functions for querying libavcodec capabilities,
195  * allocating core structures, etc.
196  * @{
197  */
198 
199 
200 /**
201  * Identify the syntax and semantics of the bitstream.
202  * The principle is roughly:
203  * Two decoders with the same ID can decode the same streams.
204  * Two encoders with the same ID can encode compatible streams.
205  * There may be slight deviations from the principle due to implementation
206  * details.
207  *
208  * If you add a codec ID to this list, add it so that
209  * 1. no value of an existing codec ID changes (that would break ABI),
210  * 2. it is as close as possible to similar codecs
211  *
212  * After adding new codec IDs, do not forget to add an entry to the codec
213  * descriptor list and bump libavcodec minor version.
214  */
215 enum AVCodecID {
216  AV_CODEC_ID_NONE,
217 
218  /* video codecs */
219  AV_CODEC_ID_MPEG1VIDEO,
220  AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
221  AV_CODEC_ID_H261,
222  AV_CODEC_ID_H263,
223  AV_CODEC_ID_RV10,
224  AV_CODEC_ID_RV20,
225  AV_CODEC_ID_MJPEG,
226  AV_CODEC_ID_MJPEGB,
227  AV_CODEC_ID_LJPEG,
228  AV_CODEC_ID_SP5X,
229  AV_CODEC_ID_JPEGLS,
230  AV_CODEC_ID_MPEG4,
231  AV_CODEC_ID_RAWVIDEO,
232  AV_CODEC_ID_MSMPEG4V1,
233  AV_CODEC_ID_MSMPEG4V2,
234  AV_CODEC_ID_MSMPEG4V3,
235  AV_CODEC_ID_WMV1,
236  AV_CODEC_ID_WMV2,
237  AV_CODEC_ID_H263P,
238  AV_CODEC_ID_H263I,
239  AV_CODEC_ID_FLV1,
240  AV_CODEC_ID_SVQ1,
241  AV_CODEC_ID_SVQ3,
242  AV_CODEC_ID_DVVIDEO,
243  AV_CODEC_ID_HUFFYUV,
244  AV_CODEC_ID_CYUV,
245  AV_CODEC_ID_H264,
246  AV_CODEC_ID_INDEO3,
247  AV_CODEC_ID_VP3,
248  AV_CODEC_ID_THEORA,
249  AV_CODEC_ID_ASV1,
250  AV_CODEC_ID_ASV2,
251  AV_CODEC_ID_FFV1,
252  AV_CODEC_ID_4XM,
253  AV_CODEC_ID_VCR1,
254  AV_CODEC_ID_CLJR,
255  AV_CODEC_ID_MDEC,
256  AV_CODEC_ID_ROQ,
257  AV_CODEC_ID_INTERPLAY_VIDEO,
258  AV_CODEC_ID_XAN_WC3,
259  AV_CODEC_ID_XAN_WC4,
260  AV_CODEC_ID_RPZA,
261  AV_CODEC_ID_CINEPAK,
262  AV_CODEC_ID_WS_VQA,
263  AV_CODEC_ID_MSRLE,
264  AV_CODEC_ID_MSVIDEO1,
265  AV_CODEC_ID_IDCIN,
266  AV_CODEC_ID_8BPS,
267  AV_CODEC_ID_SMC,
268  AV_CODEC_ID_FLIC,
269  AV_CODEC_ID_TRUEMOTION1,
270  AV_CODEC_ID_VMDVIDEO,
271  AV_CODEC_ID_MSZH,
272  AV_CODEC_ID_ZLIB,
273  AV_CODEC_ID_QTRLE,
274  AV_CODEC_ID_TSCC,
275  AV_CODEC_ID_ULTI,
276  AV_CODEC_ID_QDRAW,
277  AV_CODEC_ID_VIXL,
278  AV_CODEC_ID_QPEG,
279  AV_CODEC_ID_PNG,
280  AV_CODEC_ID_PPM,
281  AV_CODEC_ID_PBM,
282  AV_CODEC_ID_PGM,
283  AV_CODEC_ID_PGMYUV,
284  AV_CODEC_ID_PAM,
285  AV_CODEC_ID_FFVHUFF,
286  AV_CODEC_ID_RV30,
287  AV_CODEC_ID_RV40,
288  AV_CODEC_ID_VC1,
289  AV_CODEC_ID_WMV3,
290  AV_CODEC_ID_LOCO,
291  AV_CODEC_ID_WNV1,
292  AV_CODEC_ID_AASC,
293  AV_CODEC_ID_INDEO2,
294  AV_CODEC_ID_FRAPS,
295  AV_CODEC_ID_TRUEMOTION2,
296  AV_CODEC_ID_BMP,
297  AV_CODEC_ID_CSCD,
298  AV_CODEC_ID_MMVIDEO,
299  AV_CODEC_ID_ZMBV,
300  AV_CODEC_ID_AVS,
301  AV_CODEC_ID_SMACKVIDEO,
302  AV_CODEC_ID_NUV,
303  AV_CODEC_ID_KMVC,
304  AV_CODEC_ID_FLASHSV,
305  AV_CODEC_ID_CAVS,
306  AV_CODEC_ID_JPEG2000,
307  AV_CODEC_ID_VMNC,
308  AV_CODEC_ID_VP5,
309  AV_CODEC_ID_VP6,
310  AV_CODEC_ID_VP6F,
311  AV_CODEC_ID_TARGA,
312  AV_CODEC_ID_DSICINVIDEO,
313  AV_CODEC_ID_TIERTEXSEQVIDEO,
314  AV_CODEC_ID_TIFF,
315  AV_CODEC_ID_GIF,
316  AV_CODEC_ID_DXA,
317  AV_CODEC_ID_DNXHD,
318  AV_CODEC_ID_THP,
319  AV_CODEC_ID_SGI,
320  AV_CODEC_ID_C93,
321  AV_CODEC_ID_BETHSOFTVID,
322  AV_CODEC_ID_PTX,
323  AV_CODEC_ID_TXD,
324  AV_CODEC_ID_VP6A,
325  AV_CODEC_ID_AMV,
326  AV_CODEC_ID_VB,
327  AV_CODEC_ID_PCX,
328  AV_CODEC_ID_SUNRAST,
329  AV_CODEC_ID_INDEO4,
330  AV_CODEC_ID_INDEO5,
331  AV_CODEC_ID_MIMIC,
332  AV_CODEC_ID_RL2,
333  AV_CODEC_ID_ESCAPE124,
334  AV_CODEC_ID_DIRAC,
335  AV_CODEC_ID_BFI,
336  AV_CODEC_ID_CMV,
337  AV_CODEC_ID_MOTIONPIXELS,
338  AV_CODEC_ID_TGV,
339  AV_CODEC_ID_TGQ,
340  AV_CODEC_ID_TQI,
341  AV_CODEC_ID_AURA,
342  AV_CODEC_ID_AURA2,
343  AV_CODEC_ID_V210X,
344  AV_CODEC_ID_TMV,
345  AV_CODEC_ID_V210,
346  AV_CODEC_ID_DPX,
347  AV_CODEC_ID_MAD,
348  AV_CODEC_ID_FRWU,
349  AV_CODEC_ID_FLASHSV2,
350  AV_CODEC_ID_CDGRAPHICS,
351  AV_CODEC_ID_R210,
352  AV_CODEC_ID_ANM,
353  AV_CODEC_ID_BINKVIDEO,
354  AV_CODEC_ID_IFF_ILBM,
355 #define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
356  AV_CODEC_ID_KGV1,
357  AV_CODEC_ID_YOP,
358  AV_CODEC_ID_VP8,
359  AV_CODEC_ID_PICTOR,
360  AV_CODEC_ID_ANSI,
361  AV_CODEC_ID_A64_MULTI,
362  AV_CODEC_ID_A64_MULTI5,
363  AV_CODEC_ID_R10K,
364  AV_CODEC_ID_MXPEG,
365  AV_CODEC_ID_LAGARITH,
366  AV_CODEC_ID_PRORES,
367  AV_CODEC_ID_JV,
368  AV_CODEC_ID_DFA,
369  AV_CODEC_ID_WMV3IMAGE,
370  AV_CODEC_ID_VC1IMAGE,
371  AV_CODEC_ID_UTVIDEO,
372  AV_CODEC_ID_BMV_VIDEO,
373  AV_CODEC_ID_VBLE,
374  AV_CODEC_ID_DXTORY,
375  AV_CODEC_ID_V410,
376  AV_CODEC_ID_XWD,
377  AV_CODEC_ID_CDXL,
378  AV_CODEC_ID_XBM,
379  AV_CODEC_ID_ZEROCODEC,
380  AV_CODEC_ID_MSS1,
381  AV_CODEC_ID_MSA1,
382  AV_CODEC_ID_TSCC2,
383  AV_CODEC_ID_MTS2,
384  AV_CODEC_ID_CLLC,
385  AV_CODEC_ID_MSS2,
386  AV_CODEC_ID_VP9,
387  AV_CODEC_ID_AIC,
388  AV_CODEC_ID_ESCAPE130,
389  AV_CODEC_ID_G2M,
390  AV_CODEC_ID_WEBP,
391  AV_CODEC_ID_HNM4_VIDEO,
392  AV_CODEC_ID_HEVC,
393 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
394  AV_CODEC_ID_FIC,
395  AV_CODEC_ID_ALIAS_PIX,
396  AV_CODEC_ID_BRENDER_PIX,
397  AV_CODEC_ID_PAF_VIDEO,
398  AV_CODEC_ID_EXR,
399  AV_CODEC_ID_VP7,
400  AV_CODEC_ID_SANM,
401  AV_CODEC_ID_SGIRLE,
402  AV_CODEC_ID_MVC1,
403  AV_CODEC_ID_MVC2,
404  AV_CODEC_ID_HQX,
405  AV_CODEC_ID_TDSC,
406  AV_CODEC_ID_HQ_HQA,
407  AV_CODEC_ID_HAP,
408  AV_CODEC_ID_DDS,
409  AV_CODEC_ID_DXV,
410  AV_CODEC_ID_SCREENPRESSO,
411  AV_CODEC_ID_RSCC,
412  AV_CODEC_ID_AVS2,
413 
414  AV_CODEC_ID_Y41P = 0x8000,
415  AV_CODEC_ID_AVRP,
416  AV_CODEC_ID_012V,
417  AV_CODEC_ID_AVUI,
418  AV_CODEC_ID_AYUV,
419  AV_CODEC_ID_TARGA_Y216,
420  AV_CODEC_ID_V308,
421  AV_CODEC_ID_V408,
422  AV_CODEC_ID_YUV4,
423  AV_CODEC_ID_AVRN,
424  AV_CODEC_ID_CPIA,
425  AV_CODEC_ID_XFACE,
426  AV_CODEC_ID_SNOW,
427  AV_CODEC_ID_SMVJPEG,
428  AV_CODEC_ID_APNG,
429  AV_CODEC_ID_DAALA,
430  AV_CODEC_ID_CFHD,
431  AV_CODEC_ID_TRUEMOTION2RT,
432  AV_CODEC_ID_M101,
433  AV_CODEC_ID_MAGICYUV,
434  AV_CODEC_ID_SHEERVIDEO,
435  AV_CODEC_ID_YLC,
436  AV_CODEC_ID_PSD,
437  AV_CODEC_ID_PIXLET,
438  AV_CODEC_ID_SPEEDHQ,
439  AV_CODEC_ID_FMVC,
440  AV_CODEC_ID_SCPR,
441  AV_CODEC_ID_CLEARVIDEO,
442  AV_CODEC_ID_XPM,
443  AV_CODEC_ID_AV1,
444  AV_CODEC_ID_BITPACKED,
445  AV_CODEC_ID_MSCC,
446  AV_CODEC_ID_SRGC,
447  AV_CODEC_ID_SVG,
448  AV_CODEC_ID_GDV,
449  AV_CODEC_ID_FITS,
450  AV_CODEC_ID_IMM4,
451  AV_CODEC_ID_PROSUMER,
452  AV_CODEC_ID_MWSC,
453  AV_CODEC_ID_WCMV,
454  AV_CODEC_ID_RASC,
455  AV_CODEC_ID_HYMT,
456  AV_CODEC_ID_ARBC,
457  AV_CODEC_ID_AGM,
458  AV_CODEC_ID_LSCR,
459  AV_CODEC_ID_VP4,
460 
461  /* various PCM "codecs" */
462  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
463  AV_CODEC_ID_PCM_S16LE = 0x10000,
464  AV_CODEC_ID_PCM_S16BE,
465  AV_CODEC_ID_PCM_U16LE,
466  AV_CODEC_ID_PCM_U16BE,
467  AV_CODEC_ID_PCM_S8,
468  AV_CODEC_ID_PCM_U8,
469  AV_CODEC_ID_PCM_MULAW,
470  AV_CODEC_ID_PCM_ALAW,
471  AV_CODEC_ID_PCM_S32LE,
472  AV_CODEC_ID_PCM_S32BE,
473  AV_CODEC_ID_PCM_U32LE,
474  AV_CODEC_ID_PCM_U32BE,
475  AV_CODEC_ID_PCM_S24LE,
476  AV_CODEC_ID_PCM_S24BE,
477  AV_CODEC_ID_PCM_U24LE,
478  AV_CODEC_ID_PCM_U24BE,
479  AV_CODEC_ID_PCM_S24DAUD,
480  AV_CODEC_ID_PCM_ZORK,
481  AV_CODEC_ID_PCM_S16LE_PLANAR,
482  AV_CODEC_ID_PCM_DVD,
483  AV_CODEC_ID_PCM_F32BE,
484  AV_CODEC_ID_PCM_F32LE,
485  AV_CODEC_ID_PCM_F64BE,
486  AV_CODEC_ID_PCM_F64LE,
487  AV_CODEC_ID_PCM_BLURAY,
488  AV_CODEC_ID_PCM_LXF,
489  AV_CODEC_ID_S302M,
490  AV_CODEC_ID_PCM_S8_PLANAR,
491  AV_CODEC_ID_PCM_S24LE_PLANAR,
492  AV_CODEC_ID_PCM_S32LE_PLANAR,
493  AV_CODEC_ID_PCM_S16BE_PLANAR,
494 
495  AV_CODEC_ID_PCM_S64LE = 0x10800,
496  AV_CODEC_ID_PCM_S64BE,
497  AV_CODEC_ID_PCM_F16LE,
498  AV_CODEC_ID_PCM_F24LE,
499  AV_CODEC_ID_PCM_VIDC,
500 
501  /* various ADPCM codecs */
502  AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
503  AV_CODEC_ID_ADPCM_IMA_WAV,
504  AV_CODEC_ID_ADPCM_IMA_DK3,
505  AV_CODEC_ID_ADPCM_IMA_DK4,
506  AV_CODEC_ID_ADPCM_IMA_WS,
507  AV_CODEC_ID_ADPCM_IMA_SMJPEG,
508  AV_CODEC_ID_ADPCM_MS,
509  AV_CODEC_ID_ADPCM_4XM,
510  AV_CODEC_ID_ADPCM_XA,
511  AV_CODEC_ID_ADPCM_ADX,
512  AV_CODEC_ID_ADPCM_EA,
513  AV_CODEC_ID_ADPCM_G726,
514  AV_CODEC_ID_ADPCM_CT,
515  AV_CODEC_ID_ADPCM_SWF,
516  AV_CODEC_ID_ADPCM_YAMAHA,
517  AV_CODEC_ID_ADPCM_SBPRO_4,
518  AV_CODEC_ID_ADPCM_SBPRO_3,
519  AV_CODEC_ID_ADPCM_SBPRO_2,
520  AV_CODEC_ID_ADPCM_THP,
521  AV_CODEC_ID_ADPCM_IMA_AMV,
522  AV_CODEC_ID_ADPCM_EA_R1,
523  AV_CODEC_ID_ADPCM_EA_R3,
524  AV_CODEC_ID_ADPCM_EA_R2,
525  AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
526  AV_CODEC_ID_ADPCM_IMA_EA_EACS,
527  AV_CODEC_ID_ADPCM_EA_XAS,
528  AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
529  AV_CODEC_ID_ADPCM_IMA_ISS,
530  AV_CODEC_ID_ADPCM_G722,
531  AV_CODEC_ID_ADPCM_IMA_APC,
532  AV_CODEC_ID_ADPCM_VIMA,
533 
534  AV_CODEC_ID_ADPCM_AFC = 0x11800,
535  AV_CODEC_ID_ADPCM_IMA_OKI,
536  AV_CODEC_ID_ADPCM_DTK,
537  AV_CODEC_ID_ADPCM_IMA_RAD,
538  AV_CODEC_ID_ADPCM_G726LE,
539  AV_CODEC_ID_ADPCM_THP_LE,
540  AV_CODEC_ID_ADPCM_PSX,
541  AV_CODEC_ID_ADPCM_AICA,
542  AV_CODEC_ID_ADPCM_IMA_DAT4,
543  AV_CODEC_ID_ADPCM_MTAF,
544  AV_CODEC_ID_ADPCM_AGM,
545 
546  /* AMR */
547  AV_CODEC_ID_AMR_NB = 0x12000,
548  AV_CODEC_ID_AMR_WB,
549 
550  /* RealAudio codecs*/
551  AV_CODEC_ID_RA_144 = 0x13000,
552  AV_CODEC_ID_RA_288,
553 
554  /* various DPCM codecs */
555  AV_CODEC_ID_ROQ_DPCM = 0x14000,
556  AV_CODEC_ID_INTERPLAY_DPCM,
557  AV_CODEC_ID_XAN_DPCM,
558  AV_CODEC_ID_SOL_DPCM,
559 
560  AV_CODEC_ID_SDX2_DPCM = 0x14800,
561  AV_CODEC_ID_GREMLIN_DPCM,
562 
563  /* audio codecs */
564  AV_CODEC_ID_MP2 = 0x15000,
565  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
566  AV_CODEC_ID_AAC,
567  AV_CODEC_ID_AC3,
568  AV_CODEC_ID_DTS,
569  AV_CODEC_ID_VORBIS,
570  AV_CODEC_ID_DVAUDIO,
571  AV_CODEC_ID_WMAV1,
572  AV_CODEC_ID_WMAV2,
573  AV_CODEC_ID_MACE3,
574  AV_CODEC_ID_MACE6,
575  AV_CODEC_ID_VMDAUDIO,
576  AV_CODEC_ID_FLAC,
577  AV_CODEC_ID_MP3ADU,
578  AV_CODEC_ID_MP3ON4,
579  AV_CODEC_ID_SHORTEN,
580  AV_CODEC_ID_ALAC,
581  AV_CODEC_ID_WESTWOOD_SND1,
582  AV_CODEC_ID_GSM, ///< as in Berlin toast format
583  AV_CODEC_ID_QDM2,
584  AV_CODEC_ID_COOK,
585  AV_CODEC_ID_TRUESPEECH,
586  AV_CODEC_ID_TTA,
587  AV_CODEC_ID_SMACKAUDIO,
588  AV_CODEC_ID_QCELP,
589  AV_CODEC_ID_WAVPACK,
590  AV_CODEC_ID_DSICINAUDIO,
591  AV_CODEC_ID_IMC,
592  AV_CODEC_ID_MUSEPACK7,
593  AV_CODEC_ID_MLP,
594  AV_CODEC_ID_GSM_MS, /* as found in WAV */
595  AV_CODEC_ID_ATRAC3,
596  AV_CODEC_ID_APE,
597  AV_CODEC_ID_NELLYMOSER,
598  AV_CODEC_ID_MUSEPACK8,
599  AV_CODEC_ID_SPEEX,
600  AV_CODEC_ID_WMAVOICE,
601  AV_CODEC_ID_WMAPRO,
602  AV_CODEC_ID_WMALOSSLESS,
603  AV_CODEC_ID_ATRAC3P,
604  AV_CODEC_ID_EAC3,
605  AV_CODEC_ID_SIPR,
606  AV_CODEC_ID_MP1,
607  AV_CODEC_ID_TWINVQ,
608  AV_CODEC_ID_TRUEHD,
609  AV_CODEC_ID_MP4ALS,
610  AV_CODEC_ID_ATRAC1,
611  AV_CODEC_ID_BINKAUDIO_RDFT,
612  AV_CODEC_ID_BINKAUDIO_DCT,
613  AV_CODEC_ID_AAC_LATM,
614  AV_CODEC_ID_QDMC,
615  AV_CODEC_ID_CELT,
616  AV_CODEC_ID_G723_1,
617  AV_CODEC_ID_G729,
618  AV_CODEC_ID_8SVX_EXP,
619  AV_CODEC_ID_8SVX_FIB,
620  AV_CODEC_ID_BMV_AUDIO,
621  AV_CODEC_ID_RALF,
622  AV_CODEC_ID_IAC,
623  AV_CODEC_ID_ILBC,
624  AV_CODEC_ID_OPUS,
625  AV_CODEC_ID_COMFORT_NOISE,
626  AV_CODEC_ID_TAK,
627  AV_CODEC_ID_METASOUND,
628  AV_CODEC_ID_PAF_AUDIO,
629  AV_CODEC_ID_ON2AVC,
630  AV_CODEC_ID_DSS_SP,
631  AV_CODEC_ID_CODEC2,
632 
633  AV_CODEC_ID_FFWAVESYNTH = 0x15800,
634  AV_CODEC_ID_SONIC,
635  AV_CODEC_ID_SONIC_LS,
636  AV_CODEC_ID_EVRC,
637  AV_CODEC_ID_SMV,
638  AV_CODEC_ID_DSD_LSBF,
639  AV_CODEC_ID_DSD_MSBF,
640  AV_CODEC_ID_DSD_LSBF_PLANAR,
641  AV_CODEC_ID_DSD_MSBF_PLANAR,
642  AV_CODEC_ID_4GV,
643  AV_CODEC_ID_INTERPLAY_ACM,
644  AV_CODEC_ID_XMA1,
645  AV_CODEC_ID_XMA2,
646  AV_CODEC_ID_DST,
647  AV_CODEC_ID_ATRAC3AL,
648  AV_CODEC_ID_ATRAC3PAL,
649  AV_CODEC_ID_DOLBY_E,
650  AV_CODEC_ID_APTX,
651  AV_CODEC_ID_APTX_HD,
652  AV_CODEC_ID_SBC,
653  AV_CODEC_ID_ATRAC9,
654  AV_CODEC_ID_HCOM,
655 
656  /* subtitle codecs */
657  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
658  AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
659  AV_CODEC_ID_DVB_SUBTITLE,
660  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
661  AV_CODEC_ID_XSUB,
662  AV_CODEC_ID_SSA,
663  AV_CODEC_ID_MOV_TEXT,
664  AV_CODEC_ID_HDMV_PGS_SUBTITLE,
665  AV_CODEC_ID_DVB_TELETEXT,
666  AV_CODEC_ID_SRT,
667 
668  AV_CODEC_ID_MICRODVD = 0x17800,
669  AV_CODEC_ID_EIA_608,
670  AV_CODEC_ID_JACOSUB,
671  AV_CODEC_ID_SAMI,
672  AV_CODEC_ID_REALTEXT,
673  AV_CODEC_ID_STL,
674  AV_CODEC_ID_SUBVIEWER1,
675  AV_CODEC_ID_SUBVIEWER,
676  AV_CODEC_ID_SUBRIP,
677  AV_CODEC_ID_WEBVTT,
678  AV_CODEC_ID_MPL2,
679  AV_CODEC_ID_VPLAYER,
680  AV_CODEC_ID_PJS,
681  AV_CODEC_ID_ASS,
682  AV_CODEC_ID_HDMV_TEXT_SUBTITLE,
683  AV_CODEC_ID_TTML,
684  AV_CODEC_ID_ARIB_CAPTION,
685 
686  /* other specific kind of codecs (generally used for attachments) */
687  AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
688  AV_CODEC_ID_TTF = 0x18000,
689 
690  AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
691  AV_CODEC_ID_BINTEXT = 0x18800,
692  AV_CODEC_ID_XBIN,
693  AV_CODEC_ID_IDF,
694  AV_CODEC_ID_OTF,
695  AV_CODEC_ID_SMPTE_KLV,
696  AV_CODEC_ID_DVD_NAV,
697  AV_CODEC_ID_TIMED_ID3,
698  AV_CODEC_ID_BIN_DATA,
699 
700 
701  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
702 
703  AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
704  * stream (only used by libavformat) */
705  AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
706  * stream (only used by libavformat) */
707  AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
708  AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
709 };
710 
711 /**
712  * This struct describes the properties of a single codec described by an
713  * AVCodecID.
714  * @see avcodec_descriptor_get()
715  */
716 typedef struct AVCodecDescriptor {
717  enum AVCodecID id;
718  enum AVMediaType type;
719  /**
720  * Name of the codec described by this descriptor. It is non-empty and
721  * unique for each codec descriptor. It should contain alphanumeric
722  * characters and '_' only.
723  */
724  const char *name;
725  /**
726  * A more descriptive name for this codec. May be NULL.
727  */
728  const char *long_name;
729  /**
730  * Codec properties, a combination of AV_CODEC_PROP_* flags.
731  */
732  int props;
733  /**
734  * MIME type(s) associated with the codec.
735  * May be NULL; if not, a NULL-terminated array of MIME types.
736  * The first item is always non-NULL and is the preferred MIME type.
737  */
738  const char *const *mime_types;
739  /**
740  * If non-NULL, an array of profiles recognized for this codec.
741  * Terminated with FF_PROFILE_UNKNOWN.
742  */
743  const struct AVProfile *profiles;
744 } AVCodecDescriptor;
745 
746 /**
747  * Codec uses only intra compression.
748  * Video and audio codecs only.
749  */
750 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
751 /**
752  * Codec supports lossy compression. Audio and video codecs only.
753  * @note a codec may support both lossy and lossless
754  * compression modes
755  */
756 #define AV_CODEC_PROP_LOSSY (1 << 1)
757 /**
758  * Codec supports lossless compression. Audio and video codecs only.
759  */
760 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
761 /**
762  * Codec supports frame reordering. That is, the coded order (the order in which
763  * the encoded packets are output by the encoders / stored / input to the
764  * decoders) may be different from the presentation order of the corresponding
765  * frames.
766  *
767  * For codecs that do not have this property set, PTS and DTS should always be
768  * equal.
769  */
770 #define AV_CODEC_PROP_REORDER (1 << 3)
771 /**
772  * Subtitle codec is bitmap based
773  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
774  */
775 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
776 /**
777  * Subtitle codec is text based.
778  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
779  */
780 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
781 
782 /**
783  * @ingroup lavc_decoding
784  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
785  * This is mainly needed because some optimized bitstream readers read
786  * 32 or 64 bit at once and could read over the end.<br>
787  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
788  * MPEG bitstreams could cause overread and segfault.
789  */
790 #define AV_INPUT_BUFFER_PADDING_SIZE 64
791 
792 /**
793  * @ingroup lavc_encoding
794  * minimum encoding buffer size
795  * Used to avoid some checks during header writing.
796  */
797 #define AV_INPUT_BUFFER_MIN_SIZE 16384
798 
799 /**
800  * @ingroup lavc_decoding
801  */
802 enum AVDiscard{
803  /* We leave some space between them for extensions (drop some
804  * keyframes for intra-only or drop just some bidir frames). */
805  AVDISCARD_NONE =-16, ///< discard nothing
806  AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
807  AVDISCARD_NONREF = 8, ///< discard all non reference
808  AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
809  AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
810  AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
811  AVDISCARD_ALL = 48, ///< discard all
812 };
813 
814 enum AVAudioServiceType {
815  AV_AUDIO_SERVICE_TYPE_MAIN = 0,
816  AV_AUDIO_SERVICE_TYPE_EFFECTS = 1,
817  AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
818  AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED = 3,
819  AV_AUDIO_SERVICE_TYPE_DIALOGUE = 4,
820  AV_AUDIO_SERVICE_TYPE_COMMENTARY = 5,
821  AV_AUDIO_SERVICE_TYPE_EMERGENCY = 6,
822  AV_AUDIO_SERVICE_TYPE_VOICE_OVER = 7,
823  AV_AUDIO_SERVICE_TYPE_KARAOKE = 8,
824  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
825 };
826 
827 /**
828  * @ingroup lavc_encoding
829  */
830 typedef struct RcOverride{
831  int start_frame;
832  int end_frame;
833  int qscale; // If this is 0 then quality_factor will be used instead.
834  float quality_factor;
835 } RcOverride;
836 
837 /* encoding support
838  These flags can be passed in AVCodecContext.flags before initialization.
839  Note: Not everything is supported yet.
840 */
841 
842 /**
843  * Allow decoders to produce frames with data planes that are not aligned
844  * to CPU requirements (e.g. due to cropping).
845  */
846 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
847 /**
848  * Use fixed qscale.
849  */
850 #define AV_CODEC_FLAG_QSCALE (1 << 1)
851 /**
852  * 4 MV per MB allowed / advanced prediction for H.263.
853  */
854 #define AV_CODEC_FLAG_4MV (1 << 2)
855 /**
856  * Output even those frames that might be corrupted.
857  */
858 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
859 /**
860  * Use qpel MC.
861  */
862 #define AV_CODEC_FLAG_QPEL (1 << 4)
863 /**
864  * Don't output frames whose parameters differ from first
865  * decoded frame in stream.
866  */
867 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
868 /**
869  * Use internal 2pass ratecontrol in first pass mode.
870  */
871 #define AV_CODEC_FLAG_PASS1 (1 << 9)
872 /**
873  * Use internal 2pass ratecontrol in second pass mode.
874  */
875 #define AV_CODEC_FLAG_PASS2 (1 << 10)
876 /**
877  * loop filter.
878  */
879 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
880 /**
881  * Only decode/encode grayscale.
882  */
883 #define AV_CODEC_FLAG_GRAY (1 << 13)
884 /**
885  * error[?] variables will be set during encoding.
886  */
887 #define AV_CODEC_FLAG_PSNR (1 << 15)
888 /**
889  * Input bitstream might be truncated at a random location
890  * instead of only at frame boundaries.
891  */
892 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
893 /**
894  * Use interlaced DCT.
895  */
896 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
897 /**
898  * Force low delay.
899  */
900 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
901 /**
902  * Place global headers in extradata instead of every keyframe.
903  */
904 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
905 /**
906  * Use only bitexact stuff (except (I)DCT).
907  */
908 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
909 /* Fx : Flag for H.263+ extra options */
910 /**
911  * H.263 advanced intra coding / MPEG-4 AC prediction
912  */
913 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
914 /**
915  * interlaced motion estimation
916  */
917 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
918 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
919 
920 /**
921  * Allow non spec compliant speedup tricks.
922  */
923 #define AV_CODEC_FLAG2_FAST (1 << 0)
924 /**
925  * Skip bitstream encoding.
926  */
927 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
928 /**
929  * Place global headers at every keyframe instead of in extradata.
930  */
931 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
932 
933 /**
934  * timecode is in drop frame format. DEPRECATED!!!!
935  */
936 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
937 
938 /**
939  * Input bitstream might be truncated at a packet boundaries
940  * instead of only at frame boundaries.
941  */
942 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
943 /**
944  * Discard cropping information from SPS.
945  */
946 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
947 
948 /**
949  * Show all frames before the first keyframe
950  */
951 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
952 /**
953  * Export motion vectors through frame side data
954  */
955 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
956 /**
957  * Do not skip samples and export skip information as frame side data
958  */
959 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
960 /**
961  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
962  */
963 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
964 
965 /* Unsupported options :
966  * Syntax Arithmetic coding (SAC)
967  * Reference Picture Selection
968  * Independent Segment Decoding */
969 /* /Fx */
970 /* codec capabilities */
971 
972 /**
973  * Decoder can use draw_horiz_band callback.
974  */
975 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
976 /**
977  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
978  * If not set, it might not use get_buffer() at all or use operations that
979  * assume the buffer was allocated by avcodec_default_get_buffer.
980  */
981 #define AV_CODEC_CAP_DR1 (1 << 1)
982 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
983 /**
984  * Encoder or decoder requires flushing with NULL input at the end in order to
985  * give the complete and correct output.
986  *
987  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
988  * with NULL data. The user can still send NULL data to the public encode
989  * or decode function, but libavcodec will not pass it along to the codec
990  * unless this flag is set.
991  *
992  * Decoders:
993  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
994  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
995  * returns frames.
996  *
997  * Encoders:
998  * The encoder needs to be fed with NULL data at the end of encoding until the
999  * encoder no longer returns data.
1000  *
1001  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
1002  * flag also means that the encoder must set the pts and duration for
1003  * each output packet. If this flag is not set, the pts and duration will
1004  * be determined by libavcodec from the input frame.
1005  */
1006 #define AV_CODEC_CAP_DELAY (1 << 5)
1007 /**
1008  * Codec can be fed a final frame with a smaller size.
1009  * This can be used to prevent truncation of the last audio samples.
1010  */
1011 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
1012 
1013 /**
1014  * Codec can output multiple frames per AVPacket
1015  * Normally demuxers return one frame at a time, demuxers which do not do
1016  * are connected to a parser to split what they return into proper frames.
1017  * This flag is reserved to the very rare category of codecs which have a
1018  * bitstream that cannot be split into frames without timeconsuming
1019  * operations like full decoding. Demuxers carrying such bitstreams thus
1020  * may return multiple frames in a packet. This has many disadvantages like
1021  * prohibiting stream copy in many cases thus it should only be considered
1022  * as a last resort.
1023  */
1024 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1025 /**
1026  * Codec is experimental and is thus avoided in favor of non experimental
1027  * encoders
1028  */
1029 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1030 /**
1031  * Codec should fill in channel configuration and samplerate instead of container
1032  */
1033 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1034 /**
1035  * Codec supports frame-level multithreading.
1036  */
1037 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1038 /**
1039  * Codec supports slice-based (or partition-based) multithreading.
1040  */
1041 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1042 /**
1043  * Codec supports changed parameters at any point.
1044  */
1045 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1046 /**
1047  * Codec supports avctx->thread_count == 0 (auto).
1048  */
1049 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1050 /**
1051  * Audio encoder supports receiving a different number of samples in each call.
1052  */
1053 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1054 /**
1055  * Decoder is not a preferred choice for probing.
1056  * This indicates that the decoder is not a good choice for probing.
1057  * It could for example be an expensive to spin up hardware decoder,
1058  * or it could simply not provide a lot of useful information about
1059  * the stream.
1060  * A decoder marked with this flag should only be used as last resort
1061  * choice for probing.
1062  */
1063 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1064 /**
1065  * Codec is intra only.
1066  */
1067 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1068 /**
1069  * Codec is lossless.
1070  */
1071 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1072 
1073 /**
1074  * Codec is backed by a hardware implementation. Typically used to
1075  * identify a non-hwaccel hardware decoder. For information about hwaccels, use
1076  * avcodec_get_hw_config() instead.
1077  */
1078 #define AV_CODEC_CAP_HARDWARE (1 << 18)
1079 
1080 /**
1081  * Codec is potentially backed by a hardware implementation, but not
1082  * necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
1083  * implementation provides some sort of internal fallback.
1084  */
1085 #define AV_CODEC_CAP_HYBRID (1 << 19)
1086 
1087 /**
1088  * This codec takes the reordered_opaque field from input AVFrames
1089  * and returns it in the corresponding field in AVCodecContext after
1090  * encoding.
1091  */
1092 #define AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE (1 << 20)
1093 
1094 /**
1095  * Pan Scan area.
1096  * This specifies the area which should be displayed.
1097  * Note there may be multiple such areas for one frame.
1098  */
1099 typedef struct AVPanScan {
1100  /**
1101  * id
1102  * - encoding: Set by user.
1103  * - decoding: Set by libavcodec.
1104  */
1105  int id;
1106 
1107  /**
1108  * width and height in 1/16 pel
1109  * - encoding: Set by user.
1110  * - decoding: Set by libavcodec.
1111  */
1112  int width;
1113  int height;
1114 
1115  /**
1116  * position of the top left corner in 1/16 pel for up to 3 fields/frames
1117  * - encoding: Set by user.
1118  * - decoding: Set by libavcodec.
1119  */
1120  int16_t position[3][2];
1121 } AVPanScan;
1122 
1123 /**
1124  * This structure describes the bitrate properties of an encoded bitstream. It
1125  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1126  * parameters for H.264/HEVC.
1127  */
1128 typedef struct AVCPBProperties {
1129  /**
1130  * Maximum bitrate of the stream, in bits per second.
1131  * Zero if unknown or unspecified.
1132  */
1133 #if FF_API_UNSANITIZED_BITRATES
1134  int max_bitrate;
1135 #else
1136  int64_t max_bitrate;
1137 #endif
1138  /**
1139  * Minimum bitrate of the stream, in bits per second.
1140  * Zero if unknown or unspecified.
1141  */
1142 #if FF_API_UNSANITIZED_BITRATES
1143  int min_bitrate;
1144 #else
1145  int64_t min_bitrate;
1146 #endif
1147  /**
1148  * Average bitrate of the stream, in bits per second.
1149  * Zero if unknown or unspecified.
1150  */
1151 #if FF_API_UNSANITIZED_BITRATES
1152  int avg_bitrate;
1153 #else
1154  int64_t avg_bitrate;
1155 #endif
1156 
1157  /**
1158  * The size of the buffer to which the ratecontrol is applied, in bits.
1159  * Zero if unknown or unspecified.
1160  */
1161  int buffer_size;
1162 
1163  /**
1164  * The delay between the time the packet this structure is associated with
1165  * is received and the time when it should be decoded, in periods of a 27MHz
1166  * clock.
1167  *
1168  * UINT64_MAX when unknown or unspecified.
1169  */
1170  uint64_t vbv_delay;
1171 } AVCPBProperties;
1172 
1173 /**
1174  * The decoder will keep a reference to the frame and may reuse it later.
1175  */
1176 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1177 
1178 /**
1179  * @defgroup lavc_packet AVPacket
1180  *
1181  * Types and functions for working with AVPacket.
1182  * @{
1183  */
1184 enum AVPacketSideDataType {
1185  /**
1186  * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1187  * bytes worth of palette. This side data signals that a new palette is
1188  * present.
1189  */
1190  AV_PKT_DATA_PALETTE,
1191 
1192  /**
1193  * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1194  * that the extradata buffer was changed and the receiving side should
1195  * act upon it appropriately. The new extradata is embedded in the side
1196  * data buffer and should be immediately used for processing the current
1197  * frame or packet.
1198  */
1199  AV_PKT_DATA_NEW_EXTRADATA,
1200 
1201  /**
1202  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1203  * @code
1204  * u32le param_flags
1205  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1206  * s32le channel_count
1207  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1208  * u64le channel_layout
1209  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1210  * s32le sample_rate
1211  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1212  * s32le width
1213  * s32le height
1214  * @endcode
1215  */
1216  AV_PKT_DATA_PARAM_CHANGE,
1217 
1218  /**
1219  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1220  * structures with info about macroblocks relevant to splitting the
1221  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1222  * That is, it does not necessarily contain info about all macroblocks,
1223  * as long as the distance between macroblocks in the info is smaller
1224  * than the target payload size.
1225  * Each MB info structure is 12 bytes, and is laid out as follows:
1226  * @code
1227  * u32le bit offset from the start of the packet
1228  * u8 current quantizer at the start of the macroblock
1229  * u8 GOB number
1230  * u16le macroblock address within the GOB
1231  * u8 horizontal MV predictor
1232  * u8 vertical MV predictor
1233  * u8 horizontal MV predictor for block number 3
1234  * u8 vertical MV predictor for block number 3
1235  * @endcode
1236  */
1237  AV_PKT_DATA_H263_MB_INFO,
1238 
1239  /**
1240  * This side data should be associated with an audio stream and contains
1241  * ReplayGain information in form of the AVReplayGain struct.
1242  */
1243  AV_PKT_DATA_REPLAYGAIN,
1244 
1245  /**
1246  * This side data contains a 3x3 transformation matrix describing an affine
1247  * transformation that needs to be applied to the decoded video frames for
1248  * correct presentation.
1249  *
1250  * See libavutil/display.h for a detailed description of the data.
1251  */
1252  AV_PKT_DATA_DISPLAYMATRIX,
1253 
1254  /**
1255  * This side data should be associated with a video stream and contains
1256  * Stereoscopic 3D information in form of the AVStereo3D struct.
1257  */
1258  AV_PKT_DATA_STEREO3D,
1259 
1260  /**
1261  * This side data should be associated with an audio stream and corresponds
1262  * to enum AVAudioServiceType.
1263  */
1264  AV_PKT_DATA_AUDIO_SERVICE_TYPE,
1265 
1266  /**
1267  * This side data contains quality related information from the encoder.
1268  * @code
1269  * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1270  * u8 picture type
1271  * u8 error count
1272  * u16 reserved
1273  * u64le[error count] sum of squared differences between encoder in and output
1274  * @endcode
1275  */
1276  AV_PKT_DATA_QUALITY_STATS,
1277 
1278  /**
1279  * This side data contains an integer value representing the stream index
1280  * of a "fallback" track. A fallback track indicates an alternate
1281  * track to use when the current track can not be decoded for some reason.
1282  * e.g. no decoder available for codec.
1283  */
1284  AV_PKT_DATA_FALLBACK_TRACK,
1285 
1286  /**
1287  * This side data corresponds to the AVCPBProperties struct.
1288  */
1289  AV_PKT_DATA_CPB_PROPERTIES,
1290 
1291  /**
1292  * Recommmends skipping the specified number of samples
1293  * @code
1294  * u32le number of samples to skip from start of this packet
1295  * u32le number of samples to skip from end of this packet
1296  * u8 reason for start skip
1297  * u8 reason for end skip (0=padding silence, 1=convergence)
1298  * @endcode
1299  */
1300  AV_PKT_DATA_SKIP_SAMPLES,
1301 
1302  /**
1303  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1304  * the packet may contain "dual mono" audio specific to Japanese DTV
1305  * and if it is true, recommends only the selected channel to be used.
1306  * @code
1307  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1308  * @endcode
1309  */
1310  AV_PKT_DATA_JP_DUALMONO,
1311 
1312  /**
1313  * A list of zero terminated key/value strings. There is no end marker for
1314  * the list, so it is required to rely on the side data size to stop.
1315  */
1316  AV_PKT_DATA_STRINGS_METADATA,
1317 
1318  /**
1319  * Subtitle event position
1320  * @code
1321  * u32le x1
1322  * u32le y1
1323  * u32le x2
1324  * u32le y2
1325  * @endcode
1326  */
1327  AV_PKT_DATA_SUBTITLE_POSITION,
1328 
1329  /**
1330  * Data found in BlockAdditional element of matroska container. There is
1331  * no end marker for the data, so it is required to rely on the side data
1332  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1333  * by data.
1334  */
1335  AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
1336 
1337  /**
1338  * The optional first identifier line of a WebVTT cue.
1339  */
1340  AV_PKT_DATA_WEBVTT_IDENTIFIER,
1341 
1342  /**
1343  * The optional settings (rendering instructions) that immediately
1344  * follow the timestamp specifier of a WebVTT cue.
1345  */
1346  AV_PKT_DATA_WEBVTT_SETTINGS,
1347 
1348  /**
1349  * A list of zero terminated key/value strings. There is no end marker for
1350  * the list, so it is required to rely on the side data size to stop. This
1351  * side data includes updated metadata which appeared in the stream.
1352  */
1353  AV_PKT_DATA_METADATA_UPDATE,
1354 
1355  /**
1356  * MPEGTS stream ID as uint8_t, this is required to pass the stream ID
1357  * information from the demuxer to the corresponding muxer.
1358  */
1359  AV_PKT_DATA_MPEGTS_STREAM_ID,
1360 
1361  /**
1362  * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1363  * should be associated with a video stream and contains data in the form
1364  * of the AVMasteringDisplayMetadata struct.
1365  */
1366  AV_PKT_DATA_MASTERING_DISPLAY_METADATA,
1367 
1368  /**
1369  * This side data should be associated with a video stream and corresponds
1370  * to the AVSphericalMapping structure.
1371  */
1372  AV_PKT_DATA_SPHERICAL,
1373 
1374  /**
1375  * Content light level (based on CTA-861.3). This metadata should be
1376  * associated with a video stream and contains data in the form of the
1377  * AVContentLightMetadata struct.
1378  */
1379  AV_PKT_DATA_CONTENT_LIGHT_LEVEL,
1380 
1381  /**
1382  * ATSC A53 Part 4 Closed Captions. This metadata should be associated with
1383  * a video stream. A53 CC bitstream is stored as uint8_t in AVPacketSideData.data.
1384  * The number of bytes of CC data is AVPacketSideData.size.
1385  */
1386  AV_PKT_DATA_A53_CC,
1387 
1388  /**
1389  * This side data is encryption initialization data.
1390  * The format is not part of ABI, use av_encryption_init_info_* methods to
1391  * access.
1392  */
1393  AV_PKT_DATA_ENCRYPTION_INIT_INFO,
1394 
1395  /**
1396  * This side data contains encryption info for how to decrypt the packet.
1397  * The format is not part of ABI, use av_encryption_info_* methods to access.
1398  */
1399  AV_PKT_DATA_ENCRYPTION_INFO,
1400 
1401  /**
1402  * Active Format Description data consisting of a single byte as specified
1403  * in ETSI TS 101 154 using AVActiveFormatDescription enum.
1404  */
1405  AV_PKT_DATA_AFD,
1406 
1407  /**
1408  * The number of side data types.
1409  * This is not part of the public API/ABI in the sense that it may
1410  * change when new side data types are added.
1411  * This must stay the last enum value.
1412  * If its value becomes huge, some code using it
1413  * needs to be updated as it assumes it to be smaller than other limits.
1414  */
1415  AV_PKT_DATA_NB
1416 };
1417 
1418 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1419 
1420 typedef struct AVPacketSideData {
1421  uint8_t *data;
1422  int size;
1423  enum AVPacketSideDataType type;
1424 } AVPacketSideData;
1425 
1426 /**
1427  * This structure stores compressed data. It is typically exported by demuxers
1428  * and then passed as input to decoders, or received as output from encoders and
1429  * then passed to muxers.
1430  *
1431  * For video, it should typically contain one compressed frame. For audio it may
1432  * contain several compressed frames. Encoders are allowed to output empty
1433  * packets, with no compressed data, containing only side data
1434  * (e.g. to update some stream parameters at the end of encoding).
1435  *
1436  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1437  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1438  * without libavcodec and libavformat major bump.
1439  *
1440  * The semantics of data ownership depends on the buf field.
1441  * If it is set, the packet data is dynamically allocated and is
1442  * valid indefinitely until a call to av_packet_unref() reduces the
1443  * reference count to 0.
1444  *
1445  * If the buf field is not set av_packet_ref() would make a copy instead
1446  * of increasing the reference count.
1447  *
1448  * The side data is always allocated with av_malloc(), copied by
1449  * av_packet_ref() and freed by av_packet_unref().
1450  *
1451  * @see av_packet_ref
1452  * @see av_packet_unref
1453  */
1454 typedef struct AVPacket {
1455  /**
1456  * A reference to the reference-counted buffer where the packet data is
1457  * stored.
1458  * May be NULL, then the packet data is not reference-counted.
1459  */
1460  AVBufferRef *buf;
1461  /**
1462  * Presentation timestamp in AVStream->time_base units; the time at which
1463  * the decompressed packet will be presented to the user.
1464  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1465  * pts MUST be larger or equal to dts as presentation cannot happen before
1466  * decompression, unless one wants to view hex dumps. Some formats misuse
1467  * the terms dts and pts/cts to mean something different. Such timestamps
1468  * must be converted to true pts/dts before they are stored in AVPacket.
1469  */
1470  int64_t pts;
1471  /**
1472  * Decompression timestamp in AVStream->time_base units; the time at which
1473  * the packet is decompressed.
1474  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1475  */
1476  int64_t dts;
1477  uint8_t *data;
1478  int size;
1479  int stream_index;
1480  /**
1481  * A combination of AV_PKT_FLAG values
1482  */
1483  int flags;
1484  /**
1485  * Additional packet data that can be provided by the container.
1486  * Packet can contain several types of side information.
1487  */
1488  AVPacketSideData *side_data;
1489  int side_data_elems;
1490 
1491  /**
1492  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1493  * Equals next_pts - this_pts in presentation order.
1494  */
1495  int64_t duration;
1496 
1497  int64_t pos; ///< byte position in stream, -1 if unknown
1498 
1499 #if FF_API_CONVERGENCE_DURATION
1500  /**
1501  * @deprecated Same as the duration field, but as int64_t. This was required
1502  * for Matroska subtitles, whose duration values could overflow when the
1503  * duration field was still an int.
1504  */
1505  attribute_deprecated
1506  int64_t convergence_duration;
1507 #endif
1508 } AVPacket;
1509 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1510 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1511 /**
1512  * Flag is used to discard packets which are required to maintain valid
1513  * decoder state but are not required for output and should be dropped
1514  * after decoding.
1515  **/
1516 #define AV_PKT_FLAG_DISCARD 0x0004
1517 /**
1518  * The packet comes from a trusted source.
1519  *
1520  * Otherwise-unsafe constructs such as arbitrary pointers to data
1521  * outside the packet may be followed.
1522  */
1523 #define AV_PKT_FLAG_TRUSTED 0x0008
1524 /**
1525  * Flag is used to indicate packets that contain frames that can
1526  * be discarded by the decoder. I.e. Non-reference frames.
1527  */
1528 #define AV_PKT_FLAG_DISPOSABLE 0x0010
1529 
1530 
1531 enum AVSideDataParamChangeFlags {
1532  AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT = 0x0001,
1533  AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
1534  AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE = 0x0004,
1535  AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS = 0x0008,
1536 };
1537 /**
1538  * @}
1539  */
1540 
1541 struct AVCodecInternal;
1542 
1543 enum AVFieldOrder {
1544  AV_FIELD_UNKNOWN,
1545  AV_FIELD_PROGRESSIVE,
1546  AV_FIELD_TT, //< Top coded_first, top displayed first
1547  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1548  AV_FIELD_TB, //< Top coded first, bottom displayed first
1549  AV_FIELD_BT, //< Bottom coded first, top displayed first
1550 };
1551 
1552 /**
1553  * main external API structure.
1554  * New fields can be added to the end with minor version bumps.
1555  * Removal, reordering and changes to existing fields require a major
1556  * version bump.
1557  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1558  * applications.
1559  * The name string for AVOptions options matches the associated command line
1560  * parameter name and can be found in libavcodec/options_table.h
1561  * The AVOption/command line parameter names differ in some cases from the C
1562  * structure field names for historic reasons or brevity.
1563  * sizeof(AVCodecContext) must not be used outside libav*.
1564  */
1565 typedef struct AVCodecContext {
1566  /**
1567  * information on struct for av_log
1568  * - set by avcodec_alloc_context3
1569  */
1570  const AVClass *av_class;
1571  int log_level_offset;
1572 
1573  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1574  const struct AVCodec *codec;
1575  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1576 
1577  /**
1578  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1579  * This is used to work around some encoder bugs.
1580  * A demuxer should set this to what is stored in the field used to identify the codec.
1581  * If there are multiple such fields in a container then the demuxer should choose the one
1582  * which maximizes the information about the used codec.
1583  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1584  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1585  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1586  * first.
1587  * - encoding: Set by user, if not then the default based on codec_id will be used.
1588  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1589  */
1590  unsigned int codec_tag;
1591 
1592  void *priv_data;
1593 
1594  /**
1595  * Private context used for internal data.
1596  *
1597  * Unlike priv_data, this is not codec-specific. It is used in general
1598  * libavcodec functions.
1599  */
1600  struct AVCodecInternal *internal;
1601 
1602  /**
1603  * Private data of the user, can be used to carry app specific stuff.
1604  * - encoding: Set by user.
1605  * - decoding: Set by user.
1606  */
1607  void *opaque;
1608 
1609  /**
1610  * the average bitrate
1611  * - encoding: Set by user; unused for constant quantizer encoding.
1612  * - decoding: Set by user, may be overwritten by libavcodec
1613  * if this info is available in the stream
1614  */
1615  int64_t bit_rate;
1616 
1617  /**
1618  * number of bits the bitstream is allowed to diverge from the reference.
1619  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1620  * - encoding: Set by user; unused for constant quantizer encoding.
1621  * - decoding: unused
1622  */
1623  int bit_rate_tolerance;
1624 
1625  /**
1626  * Global quality for codecs which cannot change it per frame.
1627  * This should be proportional to MPEG-1/2/4 qscale.
1628  * - encoding: Set by user.
1629  * - decoding: unused
1630  */
1631  int global_quality;
1632 
1633  /**
1634  * - encoding: Set by user.
1635  * - decoding: unused
1636  */
1637  int compression_level;
1638 #define FF_COMPRESSION_DEFAULT -1
1639 
1640  /**
1641  * AV_CODEC_FLAG_*.
1642  * - encoding: Set by user.
1643  * - decoding: Set by user.
1644  */
1645  int flags;
1646 
1647  /**
1648  * AV_CODEC_FLAG2_*
1649  * - encoding: Set by user.
1650  * - decoding: Set by user.
1651  */
1652  int flags2;
1653 
1654  /**
1655  * some codecs need / can use extradata like Huffman tables.
1656  * MJPEG: Huffman tables
1657  * rv10: additional flags
1658  * MPEG-4: global headers (they can be in the bitstream or here)
1659  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1660  * than extradata_size to avoid problems if it is read with the bitstream reader.
1661  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1662  * Must be allocated with the av_malloc() family of functions.
1663  * - encoding: Set/allocated/freed by libavcodec.
1664  * - decoding: Set/allocated/freed by user.
1665  */
1666  uint8_t *extradata;
1667  int extradata_size;
1668 
1669  /**
1670  * This is the fundamental unit of time (in seconds) in terms
1671  * of which frame timestamps are represented. For fixed-fps content,
1672  * timebase should be 1/framerate and timestamp increments should be
1673  * identically 1.
1674  * This often, but not always is the inverse of the frame rate or field rate
1675  * for video. 1/time_base is not the average frame rate if the frame rate is not
1676  * constant.
1677  *
1678  * Like containers, elementary streams also can store timestamps, 1/time_base
1679  * is the unit in which these timestamps are specified.
1680  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1681  * vop_time_increment_resolution and fixed_vop_rate
1682  * (fixed_vop_rate == 0 implies that it is different from the framerate)
1683  *
1684  * - encoding: MUST be set by user.
1685  * - decoding: the use of this field for decoding is deprecated.
1686  * Use framerate instead.
1687  */
1688  AVRational time_base;
1689 
1690  /**
1691  * For some codecs, the time base is closer to the field rate than the frame rate.
1692  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1693  * if no telecine is used ...
1694  *
1695  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1696  */
1697  int ticks_per_frame;
1698 
1699  /**
1700  * Codec delay.
1701  *
1702  * Encoding: Number of frames delay there will be from the encoder input to
1703  * the decoder output. (we assume the decoder matches the spec)
1704  * Decoding: Number of frames delay in addition to what a standard decoder
1705  * as specified in the spec would produce.
1706  *
1707  * Video:
1708  * Number of frames the decoded output will be delayed relative to the
1709  * encoded input.
1710  *
1711  * Audio:
1712  * For encoding, this field is unused (see initial_padding).
1713  *
1714  * For decoding, this is the number of samples the decoder needs to
1715  * output before the decoder's output is valid. When seeking, you should
1716  * start decoding this many samples prior to your desired seek point.
1717  *
1718  * - encoding: Set by libavcodec.
1719  * - decoding: Set by libavcodec.
1720  */
1721  int delay;
1722 
1723 
1724  /* video only */
1725  /**
1726  * picture width / height.
1727  *
1728  * @note Those fields may not match the values of the last
1729  * AVFrame output by avcodec_decode_video2 due frame
1730  * reordering.
1731  *
1732  * - encoding: MUST be set by user.
1733  * - decoding: May be set by the user before opening the decoder if known e.g.
1734  * from the container. Some decoders will require the dimensions
1735  * to be set by the caller. During decoding, the decoder may
1736  * overwrite those values as required while parsing the data.
1737  */
1738  int width, height;
1739 
1740  /**
1741  * Bitstream width / height, may be different from width/height e.g. when
1742  * the decoded frame is cropped before being output or lowres is enabled.
1743  *
1744  * @note Those field may not match the value of the last
1745  * AVFrame output by avcodec_receive_frame() due frame
1746  * reordering.
1747  *
1748  * - encoding: unused
1749  * - decoding: May be set by the user before opening the decoder if known
1750  * e.g. from the container. During decoding, the decoder may
1751  * overwrite those values as required while parsing the data.
1752  */
1753  int coded_width, coded_height;
1754 
1755  /**
1756  * the number of pictures in a group of pictures, or 0 for intra_only
1757  * - encoding: Set by user.
1758  * - decoding: unused
1759  */
1760  int gop_size;
1761 
1762  /**
1763  * Pixel format, see AV_PIX_FMT_xxx.
1764  * May be set by the demuxer if known from headers.
1765  * May be overridden by the decoder if it knows better.
1766  *
1767  * @note This field may not match the value of the last
1768  * AVFrame output by avcodec_receive_frame() due frame
1769  * reordering.
1770  *
1771  * - encoding: Set by user.
1772  * - decoding: Set by user if known, overridden by libavcodec while
1773  * parsing the data.
1774  */
1775  enum AVPixelFormat pix_fmt;
1776 
1777  /**
1778  * If non NULL, 'draw_horiz_band' is called by the libavcodec
1779  * decoder to draw a horizontal band. It improves cache usage. Not
1780  * all codecs can do that. You must check the codec capabilities
1781  * beforehand.
1782  * When multithreading is used, it may be called from multiple threads
1783  * at the same time; threads might draw different parts of the same AVFrame,
1784  * or multiple AVFrames, and there is no guarantee that slices will be drawn
1785  * in order.
1786  * The function is also used by hardware acceleration APIs.
1787  * It is called at least once during frame decoding to pass
1788  * the data needed for hardware render.
1789  * In that mode instead of pixel data, AVFrame points to
1790  * a structure specific to the acceleration API. The application
1791  * reads the structure and can change some fields to indicate progress
1792  * or mark state.
1793  * - encoding: unused
1794  * - decoding: Set by user.
1795  * @param height the height of the slice
1796  * @param y the y position of the slice
1797  * @param type 1->top field, 2->bottom field, 3->frame
1798  * @param offset offset into the AVFrame.data from which the slice should be read
1799  */
1800  void (*draw_horiz_band)(struct AVCodecContext *s,
1801  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1802  int y, int type, int height);
1803 
1804  /**
1805  * callback to negotiate the pixelFormat
1806  * @param fmt is the list of formats which are supported by the codec,
1807  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1808  * The first is always the native one.
1809  * @note The callback may be called again immediately if initialization for
1810  * the selected (hardware-accelerated) pixel format failed.
1811  * @warning Behavior is undefined if the callback returns a value not
1812  * in the fmt list of formats.
1813  * @return the chosen format
1814  * - encoding: unused
1815  * - decoding: Set by user, if not set the native format will be chosen.
1816  */
1817  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1818 
1819  /**
1820  * maximum number of B-frames between non-B-frames
1821  * Note: The output will be delayed by max_b_frames+1 relative to the input.
1822  * - encoding: Set by user.
1823  * - decoding: unused
1824  */
1825  int max_b_frames;
1826 
1827  /**
1828  * qscale factor between IP and B-frames
1829  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1830  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1831  * - encoding: Set by user.
1832  * - decoding: unused
1833  */
1834  float b_quant_factor;
1835 
1836 #if FF_API_PRIVATE_OPT
1837  /** @deprecated use encoder private options instead */
1838  attribute_deprecated
1839  int b_frame_strategy;
1840 #endif
1841 
1842  /**
1843  * qscale offset between IP and B-frames
1844  * - encoding: Set by user.
1845  * - decoding: unused
1846  */
1847  float b_quant_offset;
1848 
1849  /**
1850  * Size of the frame reordering buffer in the decoder.
1851  * For MPEG-2 it is 1 IPB or 0 low delay IP.
1852  * - encoding: Set by libavcodec.
1853  * - decoding: Set by libavcodec.
1854  */
1855  int has_b_frames;
1856 
1857 #if FF_API_PRIVATE_OPT
1858  /** @deprecated use encoder private options instead */
1859  attribute_deprecated
1860  int mpeg_quant;
1861 #endif
1862 
1863  /**
1864  * qscale factor between P- and I-frames
1865  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
1866  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1867  * - encoding: Set by user.
1868  * - decoding: unused
1869  */
1870  float i_quant_factor;
1871 
1872  /**
1873  * qscale offset between P and I-frames
1874  * - encoding: Set by user.
1875  * - decoding: unused
1876  */
1877  float i_quant_offset;
1878 
1879  /**
1880  * luminance masking (0-> disabled)
1881  * - encoding: Set by user.
1882  * - decoding: unused
1883  */
1884  float lumi_masking;
1885 
1886  /**
1887  * temporary complexity masking (0-> disabled)
1888  * - encoding: Set by user.
1889  * - decoding: unused
1890  */
1891  float temporal_cplx_masking;
1892 
1893  /**
1894  * spatial complexity masking (0-> disabled)
1895  * - encoding: Set by user.
1896  * - decoding: unused
1897  */
1898  float spatial_cplx_masking;
1899 
1900  /**
1901  * p block masking (0-> disabled)
1902  * - encoding: Set by user.
1903  * - decoding: unused
1904  */
1905  float p_masking;
1906 
1907  /**
1908  * darkness masking (0-> disabled)
1909  * - encoding: Set by user.
1910  * - decoding: unused
1911  */
1912  float dark_masking;
1913 
1914  /**
1915  * slice count
1916  * - encoding: Set by libavcodec.
1917  * - decoding: Set by user (or 0).
1918  */
1919  int slice_count;
1920 
1921 #if FF_API_PRIVATE_OPT
1922  /** @deprecated use encoder private options instead */
1923  attribute_deprecated
1924  int prediction_method;
1925 #define FF_PRED_LEFT 0
1926 #define FF_PRED_PLANE 1
1927 #define FF_PRED_MEDIAN 2
1928 #endif
1929 
1930  /**
1931  * slice offsets in the frame in bytes
1932  * - encoding: Set/allocated by libavcodec.
1933  * - decoding: Set/allocated by user (or NULL).
1934  */
1935  int *slice_offset;
1936 
1937  /**
1938  * sample aspect ratio (0 if unknown)
1939  * That is the width of a pixel divided by the height of the pixel.
1940  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1941  * - encoding: Set by user.
1942  * - decoding: Set by libavcodec.
1943  */
1944  AVRational sample_aspect_ratio;
1945 
1946  /**
1947  * motion estimation comparison function
1948  * - encoding: Set by user.
1949  * - decoding: unused
1950  */
1951  int me_cmp;
1952  /**
1953  * subpixel motion estimation comparison function
1954  * - encoding: Set by user.
1955  * - decoding: unused
1956  */
1957  int me_sub_cmp;
1958  /**
1959  * macroblock comparison function (not supported yet)
1960  * - encoding: Set by user.
1961  * - decoding: unused
1962  */
1963  int mb_cmp;
1964  /**
1965  * interlaced DCT comparison function
1966  * - encoding: Set by user.
1967  * - decoding: unused
1968  */
1969  int ildct_cmp;
1970 #define FF_CMP_SAD 0
1971 #define FF_CMP_SSE 1
1972 #define FF_CMP_SATD 2
1973 #define FF_CMP_DCT 3
1974 #define FF_CMP_PSNR 4
1975 #define FF_CMP_BIT 5
1976 #define FF_CMP_RD 6
1977 #define FF_CMP_ZERO 7
1978 #define FF_CMP_VSAD 8
1979 #define FF_CMP_VSSE 9
1980 #define FF_CMP_NSSE 10
1981 #define FF_CMP_W53 11
1982 #define FF_CMP_W97 12
1983 #define FF_CMP_DCTMAX 13
1984 #define FF_CMP_DCT264 14
1985 #define FF_CMP_MEDIAN_SAD 15
1986 #define FF_CMP_CHROMA 256
1987 
1988  /**
1989  * ME diamond size & shape
1990  * - encoding: Set by user.
1991  * - decoding: unused
1992  */
1993  int dia_size;
1994 
1995  /**
1996  * amount of previous MV predictors (2a+1 x 2a+1 square)
1997  * - encoding: Set by user.
1998  * - decoding: unused
1999  */
2000  int last_predictor_count;
2001 
2002 #if FF_API_PRIVATE_OPT
2003  /** @deprecated use encoder private options instead */
2004  attribute_deprecated
2005  int pre_me;
2006 #endif
2007 
2008  /**
2009  * motion estimation prepass comparison function
2010  * - encoding: Set by user.
2011  * - decoding: unused
2012  */
2013  int me_pre_cmp;
2014 
2015  /**
2016  * ME prepass diamond size & shape
2017  * - encoding: Set by user.
2018  * - decoding: unused
2019  */
2020  int pre_dia_size;
2021 
2022  /**
2023  * subpel ME quality
2024  * - encoding: Set by user.
2025  * - decoding: unused
2026  */
2027  int me_subpel_quality;
2028 
2029  /**
2030  * maximum motion estimation search range in subpel units
2031  * If 0 then no limit.
2032  *
2033  * - encoding: Set by user.
2034  * - decoding: unused
2035  */
2036  int me_range;
2037 
2038  /**
2039  * slice flags
2040  * - encoding: unused
2041  * - decoding: Set by user.
2042  */
2043  int slice_flags;
2044 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
2045 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
2046 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
2047 
2048  /**
2049  * macroblock decision mode
2050  * - encoding: Set by user.
2051  * - decoding: unused
2052  */
2053  int mb_decision;
2054 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
2055 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
2056 #define FF_MB_DECISION_RD 2 ///< rate distortion
2057 
2058  /**
2059  * custom intra quantization matrix
2060  * - encoding: Set by user, can be NULL.
2061  * - decoding: Set by libavcodec.
2062  */
2063  uint16_t *intra_matrix;
2064 
2065  /**
2066  * custom inter quantization matrix
2067  * - encoding: Set by user, can be NULL.
2068  * - decoding: Set by libavcodec.
2069  */
2070  uint16_t *inter_matrix;
2071 
2072 #if FF_API_PRIVATE_OPT
2073  /** @deprecated use encoder private options instead */
2074  attribute_deprecated
2075  int scenechange_threshold;
2076 
2077  /** @deprecated use encoder private options instead */
2078  attribute_deprecated
2079  int noise_reduction;
2080 #endif
2081 
2082  /**
2083  * precision of the intra DC coefficient - 8
2084  * - encoding: Set by user.
2085  * - decoding: Set by libavcodec
2086  */
2087  int intra_dc_precision;
2088 
2089  /**
2090  * Number of macroblock rows at the top which are skipped.
2091  * - encoding: unused
2092  * - decoding: Set by user.
2093  */
2094  int skip_top;
2095 
2096  /**
2097  * Number of macroblock rows at the bottom which are skipped.
2098  * - encoding: unused
2099  * - decoding: Set by user.
2100  */
2101  int skip_bottom;
2102 
2103  /**
2104  * minimum MB Lagrange multiplier
2105  * - encoding: Set by user.
2106  * - decoding: unused
2107  */
2108  int mb_lmin;
2109 
2110  /**
2111  * maximum MB Lagrange multiplier
2112  * - encoding: Set by user.
2113  * - decoding: unused
2114  */
2115  int mb_lmax;
2116 
2117 #if FF_API_PRIVATE_OPT
2118  /**
2119  * @deprecated use encoder private options instead
2120  */
2121  attribute_deprecated
2122  int me_penalty_compensation;
2123 #endif
2124 
2125  /**
2126  * - encoding: Set by user.
2127  * - decoding: unused
2128  */
2129  int bidir_refine;
2130 
2131 #if FF_API_PRIVATE_OPT
2132  /** @deprecated use encoder private options instead */
2133  attribute_deprecated
2134  int brd_scale;
2135 #endif
2136 
2137  /**
2138  * minimum GOP size
2139  * - encoding: Set by user.
2140  * - decoding: unused
2141  */
2142  int keyint_min;
2143 
2144  /**
2145  * number of reference frames
2146  * - encoding: Set by user.
2147  * - decoding: Set by lavc.
2148  */
2149  int refs;
2150 
2151 #if FF_API_PRIVATE_OPT
2152  /** @deprecated use encoder private options instead */
2153  attribute_deprecated
2154  int chromaoffset;
2155 #endif
2156 
2157  /**
2158  * Note: Value depends upon the compare function used for fullpel ME.
2159  * - encoding: Set by user.
2160  * - decoding: unused
2161  */
2162  int mv0_threshold;
2163 
2164 #if FF_API_PRIVATE_OPT
2165  /** @deprecated use encoder private options instead */
2166  attribute_deprecated
2167  int b_sensitivity;
2168 #endif
2169 
2170  /**
2171  * Chromaticity coordinates of the source primaries.
2172  * - encoding: Set by user
2173  * - decoding: Set by libavcodec
2174  */
2175  enum AVColorPrimaries color_primaries;
2176 
2177  /**
2178  * Color Transfer Characteristic.
2179  * - encoding: Set by user
2180  * - decoding: Set by libavcodec
2181  */
2182  enum AVColorTransferCharacteristic color_trc;
2183 
2184  /**
2185  * YUV colorspace type.
2186  * - encoding: Set by user
2187  * - decoding: Set by libavcodec
2188  */
2189  enum AVColorSpace colorspace;
2190 
2191  /**
2192  * MPEG vs JPEG YUV range.
2193  * - encoding: Set by user
2194  * - decoding: Set by libavcodec
2195  */
2196  enum AVColorRange color_range;
2197 
2198  /**
2199  * This defines the location of chroma samples.
2200  * - encoding: Set by user
2201  * - decoding: Set by libavcodec
2202  */
2203  enum AVChromaLocation chroma_sample_location;
2204 
2205  /**
2206  * Number of slices.
2207  * Indicates number of picture subdivisions. Used for parallelized
2208  * decoding.
2209  * - encoding: Set by user
2210  * - decoding: unused
2211  */
2212  int slices;
2213 
2214  /** Field order
2215  * - encoding: set by libavcodec
2216  * - decoding: Set by user.
2217  */
2218  enum AVFieldOrder field_order;
2219 
2220  /* audio only */
2221  int sample_rate; ///< samples per second
2222  int channels; ///< number of audio channels
2223 
2224  /**
2225  * audio sample format
2226  * - encoding: Set by user.
2227  * - decoding: Set by libavcodec.
2228  */
2229  enum AVSampleFormat sample_fmt; ///< sample format
2230 
2231  /* The following data should not be initialized. */
2232  /**
2233  * Number of samples per channel in an audio frame.
2234  *
2235  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2236  * except the last must contain exactly frame_size samples per channel.
2237  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2238  * frame size is not restricted.
2239  * - decoding: may be set by some decoders to indicate constant frame size
2240  */
2241  int frame_size;
2242 
2243  /**
2244  * Frame counter, set by libavcodec.
2245  *
2246  * - decoding: total number of frames returned from the decoder so far.
2247  * - encoding: total number of frames passed to the encoder so far.
2248  *
2249  * @note the counter is not incremented if encoding/decoding resulted in
2250  * an error.
2251  */
2252  int frame_number;
2253 
2254  /**
2255  * number of bytes per packet if constant and known or 0
2256  * Used by some WAV based audio codecs.
2257  */
2258  int block_align;
2259 
2260  /**
2261  * Audio cutoff bandwidth (0 means "automatic")
2262  * - encoding: Set by user.
2263  * - decoding: unused
2264  */
2265  int cutoff;
2266 
2267  /**
2268  * Audio channel layout.
2269  * - encoding: set by user.
2270  * - decoding: set by user, may be overwritten by libavcodec.
2271  */
2272  uint64_t channel_layout;
2273 
2274  /**
2275  * Request decoder to use this channel layout if it can (0 for default)
2276  * - encoding: unused
2277  * - decoding: Set by user.
2278  */
2279  uint64_t request_channel_layout;
2280 
2281  /**
2282  * Type of service that the audio stream conveys.
2283  * - encoding: Set by user.
2284  * - decoding: Set by libavcodec.
2285  */
2286  enum AVAudioServiceType audio_service_type;
2287 
2288  /**
2289  * desired sample format
2290  * - encoding: Not used.
2291  * - decoding: Set by user.
2292  * Decoder will decode to this format if it can.
2293  */
2294  enum AVSampleFormat request_sample_fmt;
2295 
2296  /**
2297  * This callback is called at the beginning of each frame to get data
2298  * buffer(s) for it. There may be one contiguous buffer for all the data or
2299  * there may be a buffer per each data plane or anything in between. What
2300  * this means is, you may set however many entries in buf[] you feel necessary.
2301  * Each buffer must be reference-counted using the AVBuffer API (see description
2302  * of buf[] below).
2303  *
2304  * The following fields will be set in the frame before this callback is
2305  * called:
2306  * - format
2307  * - width, height (video only)
2308  * - sample_rate, channel_layout, nb_samples (audio only)
2309  * Their values may differ from the corresponding values in
2310  * AVCodecContext. This callback must use the frame values, not the codec
2311  * context values, to calculate the required buffer size.
2312  *
2313  * This callback must fill the following fields in the frame:
2314  * - data[]
2315  * - linesize[]
2316  * - extended_data:
2317  * * if the data is planar audio with more than 8 channels, then this
2318  * callback must allocate and fill extended_data to contain all pointers
2319  * to all data planes. data[] must hold as many pointers as it can.
2320  * extended_data must be allocated with av_malloc() and will be freed in
2321  * av_frame_unref().
2322  * * otherwise extended_data must point to data
2323  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2324  * the frame's data and extended_data pointers must be contained in these. That
2325  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2326  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2327  * and av_buffer_ref().
2328  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2329  * this callback and filled with the extra buffers if there are more
2330  * buffers than buf[] can hold. extended_buf will be freed in
2331  * av_frame_unref().
2332  *
2333  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2334  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2335  * some other means.
2336  *
2337  * Each data plane must be aligned to the maximum required by the target
2338  * CPU.
2339  *
2340  * @see avcodec_default_get_buffer2()
2341  *
2342  * Video:
2343  *
2344  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2345  * (read and/or written to if it is writable) later by libavcodec.
2346  *
2347  * avcodec_align_dimensions2() should be used to find the required width and
2348  * height, as they normally need to be rounded up to the next multiple of 16.
2349  *
2350  * Some decoders do not support linesizes changing between frames.
2351  *
2352  * If frame multithreading is used and thread_safe_callbacks is set,
2353  * this callback may be called from a different thread, but not from more
2354  * than one at once. Does not need to be reentrant.
2355  *
2356  * @see avcodec_align_dimensions2()
2357  *
2358  * Audio:
2359  *
2360  * Decoders request a buffer of a particular size by setting
2361  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2362  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2363  * to a smaller value in the output frame.
2364  *
2365  * As a convenience, av_samples_get_buffer_size() and
2366  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2367  * functions to find the required data size and to fill data pointers and
2368  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2369  * since all planes must be the same size.
2370  *
2371  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2372  *
2373  * - encoding: unused
2374  * - decoding: Set by libavcodec, user can override.
2375  */
2376  int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
2377 
2378  /**
2379  * If non-zero, the decoded audio and video frames returned from
2380  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2381  * and are valid indefinitely. The caller must free them with
2382  * av_frame_unref() when they are not needed anymore.
2383  * Otherwise, the decoded frames must not be freed by the caller and are
2384  * only valid until the next decode call.
2385  *
2386  * This is always automatically enabled if avcodec_receive_frame() is used.
2387  *
2388  * - encoding: unused
2389  * - decoding: set by the caller before avcodec_open2().
2390  */
2391  attribute_deprecated
2392  int refcounted_frames;
2393 
2394  /* - encoding parameters */
2395  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2396  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2397 
2398  /**
2399  * minimum quantizer
2400  * - encoding: Set by user.
2401  * - decoding: unused
2402  */
2403  int qmin;
2404 
2405  /**
2406  * maximum quantizer
2407  * - encoding: Set by user.
2408  * - decoding: unused
2409  */
2410  int qmax;
2411 
2412  /**
2413  * maximum quantizer difference between frames
2414  * - encoding: Set by user.
2415  * - decoding: unused
2416  */
2417  int max_qdiff;
2418 
2419  /**
2420  * decoder bitstream buffer size
2421  * - encoding: Set by user.
2422  * - decoding: unused
2423  */
2424  int rc_buffer_size;
2425 
2426  /**
2427  * ratecontrol override, see RcOverride
2428  * - encoding: Allocated/set/freed by user.
2429  * - decoding: unused
2430  */
2431  int rc_override_count;
2432  RcOverride *rc_override;
2433 
2434  /**
2435  * maximum bitrate
2436  * - encoding: Set by user.
2437  * - decoding: Set by user, may be overwritten by libavcodec.
2438  */
2439  int64_t rc_max_rate;
2440 
2441  /**
2442  * minimum bitrate
2443  * - encoding: Set by user.
2444  * - decoding: unused
2445  */
2446  int64_t rc_min_rate;
2447 
2448  /**
2449  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2450  * - encoding: Set by user.
2451  * - decoding: unused.
2452  */
2453  float rc_max_available_vbv_use;
2454 
2455  /**
2456  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2457  * - encoding: Set by user.
2458  * - decoding: unused.
2459  */
2460  float rc_min_vbv_overflow_use;
2461 
2462  /**
2463  * Number of bits which should be loaded into the rc buffer before decoding starts.
2464  * - encoding: Set by user.
2465  * - decoding: unused
2466  */
2467  int rc_initial_buffer_occupancy;
2468 
2469 #if FF_API_CODER_TYPE
2470 #define FF_CODER_TYPE_VLC 0
2471 #define FF_CODER_TYPE_AC 1
2472 #define FF_CODER_TYPE_RAW 2
2473 #define FF_CODER_TYPE_RLE 3
2474  /**
2475  * @deprecated use encoder private options instead
2476  */
2477  attribute_deprecated
2478  int coder_type;
2479 #endif /* FF_API_CODER_TYPE */
2480 
2481 #if FF_API_PRIVATE_OPT
2482  /** @deprecated use encoder private options instead */
2483  attribute_deprecated
2484  int context_model;
2485 #endif
2486 
2487 #if FF_API_PRIVATE_OPT
2488  /** @deprecated use encoder private options instead */
2489  attribute_deprecated
2490  int frame_skip_threshold;
2491 
2492  /** @deprecated use encoder private options instead */
2493  attribute_deprecated
2494  int frame_skip_factor;
2495 
2496  /** @deprecated use encoder private options instead */
2497  attribute_deprecated
2498  int frame_skip_exp;
2499 
2500  /** @deprecated use encoder private options instead */
2501  attribute_deprecated
2502  int frame_skip_cmp;
2503 #endif /* FF_API_PRIVATE_OPT */
2504 
2505  /**
2506  * trellis RD quantization
2507  * - encoding: Set by user.
2508  * - decoding: unused
2509  */
2510  int trellis;
2511 
2512 #if FF_API_PRIVATE_OPT
2513  /** @deprecated use encoder private options instead */
2514  attribute_deprecated
2515  int min_prediction_order;
2516 
2517  /** @deprecated use encoder private options instead */
2518  attribute_deprecated
2519  int max_prediction_order;
2520 
2521  /** @deprecated use encoder private options instead */
2522  attribute_deprecated
2523  int64_t timecode_frame_start;
2524 #endif
2525 
2526 #if FF_API_RTP_CALLBACK
2527  /**
2528  * @deprecated unused
2529  */
2530  /* The RTP callback: This function is called */
2531  /* every time the encoder has a packet to send. */
2532  /* It depends on the encoder if the data starts */
2533  /* with a Start Code (it should). H.263 does. */
2534  /* mb_nb contains the number of macroblocks */
2535  /* encoded in the RTP payload. */
2536  attribute_deprecated
2537  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2538 #endif
2539 
2540 #if FF_API_PRIVATE_OPT
2541  /** @deprecated use encoder private options instead */
2542  attribute_deprecated
2543  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2544  /* do its best to deliver a chunk with size */
2545  /* below rtp_payload_size, the chunk will start */
2546  /* with a start code on some codecs like H.263. */
2547  /* This doesn't take account of any particular */
2548  /* headers inside the transmitted RTP payload. */
2549 #endif
2550 
2551 #if FF_API_STAT_BITS
2552  /* statistics, used for 2-pass encoding */
2553  attribute_deprecated
2554  int mv_bits;
2555  attribute_deprecated
2556  int header_bits;
2557  attribute_deprecated
2558  int i_tex_bits;
2559  attribute_deprecated
2560  int p_tex_bits;
2561  attribute_deprecated
2562  int i_count;
2563  attribute_deprecated
2564  int p_count;
2565  attribute_deprecated
2566  int skip_count;
2567  attribute_deprecated
2568  int misc_bits;
2569 
2570  /** @deprecated this field is unused */
2571  attribute_deprecated
2572  int frame_bits;
2573 #endif
2574 
2575  /**
2576  * pass1 encoding statistics output buffer
2577  * - encoding: Set by libavcodec.
2578  * - decoding: unused
2579  */
2580  char *stats_out;
2581 
2582  /**
2583  * pass2 encoding statistics input buffer
2584  * Concatenated stuff from stats_out of pass1 should be placed here.
2585  * - encoding: Allocated/set/freed by user.
2586  * - decoding: unused
2587  */
2588  char *stats_in;
2589 
2590  /**
2591  * Work around bugs in encoders which sometimes cannot be detected automatically.
2592  * - encoding: Set by user
2593  * - decoding: Set by user
2594  */
2595  int workaround_bugs;
2596 #define FF_BUG_AUTODETECT 1 ///< autodetection
2597 #define FF_BUG_XVID_ILACE 4
2598 #define FF_BUG_UMP4 8
2599 #define FF_BUG_NO_PADDING 16
2600 #define FF_BUG_AMV 32
2601 #define FF_BUG_QPEL_CHROMA 64
2602 #define FF_BUG_STD_QPEL 128
2603 #define FF_BUG_QPEL_CHROMA2 256
2604 #define FF_BUG_DIRECT_BLOCKSIZE 512
2605 #define FF_BUG_EDGE 1024
2606 #define FF_BUG_HPEL_CHROMA 2048
2607 #define FF_BUG_DC_CLIP 4096
2608 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2609 #define FF_BUG_TRUNCATED 16384
2610 #define FF_BUG_IEDGE 32768
2611 
2612  /**
2613  * strictly follow the standard (MPEG-4, ...).
2614  * - encoding: Set by user.
2615  * - decoding: Set by user.
2616  * Setting this to STRICT or higher means the encoder and decoder will
2617  * generally do stupid things, whereas setting it to unofficial or lower
2618  * will mean the encoder might produce output that is not supported by all
2619  * spec-compliant decoders. Decoders don't differentiate between normal,
2620  * unofficial and experimental (that is, they always try to decode things
2621  * when they can) unless they are explicitly asked to behave stupidly
2622  * (=strictly conform to the specs)
2623  */
2624  int strict_std_compliance;
2625 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2626 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2627 #define FF_COMPLIANCE_NORMAL 0
2628 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2629 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2630 
2631  /**
2632  * error concealment flags
2633  * - encoding: unused
2634  * - decoding: Set by user.
2635  */
2636  int error_concealment;
2637 #define FF_EC_GUESS_MVS 1
2638 #define FF_EC_DEBLOCK 2
2639 #define FF_EC_FAVOR_INTER 256
2640 
2641  /**
2642  * debug
2643  * - encoding: Set by user.
2644  * - decoding: Set by user.
2645  */
2646  int debug;
2647 #define FF_DEBUG_PICT_INFO 1
2648 #define FF_DEBUG_RC 2
2649 #define FF_DEBUG_BITSTREAM 4
2650 #define FF_DEBUG_MB_TYPE 8
2651 #define FF_DEBUG_QP 16
2652 #if FF_API_DEBUG_MV
2653 /**
2654  * @deprecated this option does nothing
2655  */
2656 #define FF_DEBUG_MV 32
2657 #endif
2658 #define FF_DEBUG_DCT_COEFF 0x00000040
2659 #define FF_DEBUG_SKIP 0x00000080
2660 #define FF_DEBUG_STARTCODE 0x00000100
2661 #define FF_DEBUG_ER 0x00000400
2662 #define FF_DEBUG_MMCO 0x00000800
2663 #define FF_DEBUG_BUGS 0x00001000
2664 #if FF_API_DEBUG_MV
2665 #define FF_DEBUG_VIS_QP 0x00002000
2666 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2667 #endif
2668 #define FF_DEBUG_BUFFERS 0x00008000
2669 #define FF_DEBUG_THREADS 0x00010000
2670 #define FF_DEBUG_GREEN_MD 0x00800000
2671 #define FF_DEBUG_NOMC 0x01000000
2672 
2673 #if FF_API_DEBUG_MV
2674  /**
2675  * debug
2676  * - encoding: Set by user.
2677  * - decoding: Set by user.
2678  */
2679  int debug_mv;
2680 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
2681 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
2682 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
2683 #endif
2684 
2685  /**
2686  * Error recognition; may misdetect some more or less valid parts as errors.
2687  * - encoding: unused
2688  * - decoding: Set by user.
2689  */
2690  int err_recognition;
2691 
2692 /**
2693  * Verify checksums embedded in the bitstream (could be of either encoded or
2694  * decoded data, depending on the codec) and print an error message on mismatch.
2695  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2696  * decoder returning an error.
2697  */
2698 #define AV_EF_CRCCHECK (1<<0)
2699 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2700 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2701 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2702 
2703 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2704 #define AV_EF_CAREFUL (1<<16) ///< consider things that violate the spec, are fast to calculate and have not been seen in the wild as errors
2705 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2706 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2707 
2708 
2709  /**
2710  * opaque 64-bit number (generally a PTS) that will be reordered and
2711  * output in AVFrame.reordered_opaque
2712  * - encoding: Set by libavcodec to the reordered_opaque of the input
2713  * frame corresponding to the last returned packet. Only
2714  * supported by encoders with the
2715  * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
2716  * - decoding: Set by user.
2717  */
2718  int64_t reordered_opaque;
2719 
2720  /**
2721  * Hardware accelerator in use
2722  * - encoding: unused.
2723  * - decoding: Set by libavcodec
2724  */
2725  const struct AVHWAccel *hwaccel;
2726 
2727  /**
2728  * Hardware accelerator context.
2729  * For some hardware accelerators, a global context needs to be
2730  * provided by the user. In that case, this holds display-dependent
2731  * data FFmpeg cannot instantiate itself. Please refer to the
2732  * FFmpeg HW accelerator documentation to know how to fill this
2733  * is. e.g. for VA API, this is a struct vaapi_context.
2734  * - encoding: unused
2735  * - decoding: Set by user
2736  */
2737  void *hwaccel_context;
2738 
2739  /**
2740  * error
2741  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
2742  * - decoding: unused
2743  */
2744  uint64_t error[AV_NUM_DATA_POINTERS];
2745 
2746  /**
2747  * DCT algorithm, see FF_DCT_* below
2748  * - encoding: Set by user.
2749  * - decoding: unused
2750  */
2751  int dct_algo;
2752 #define FF_DCT_AUTO 0
2753 #define FF_DCT_FASTINT 1
2754 #define FF_DCT_INT 2
2755 #define FF_DCT_MMX 3
2756 #define FF_DCT_ALTIVEC 5
2757 #define FF_DCT_FAAN 6
2758 
2759  /**
2760  * IDCT algorithm, see FF_IDCT_* below.
2761  * - encoding: Set by user.
2762  * - decoding: Set by user.
2763  */
2764  int idct_algo;
2765 #define FF_IDCT_AUTO 0
2766 #define FF_IDCT_INT 1
2767 #define FF_IDCT_SIMPLE 2
2768 #define FF_IDCT_SIMPLEMMX 3
2769 #define FF_IDCT_ARM 7
2770 #define FF_IDCT_ALTIVEC 8
2771 #define FF_IDCT_SIMPLEARM 10
2772 #define FF_IDCT_XVID 14
2773 #define FF_IDCT_SIMPLEARMV5TE 16
2774 #define FF_IDCT_SIMPLEARMV6 17
2775 #define FF_IDCT_FAAN 20
2776 #define FF_IDCT_SIMPLENEON 22
2777 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
2778 #define FF_IDCT_SIMPLEAUTO 128
2779 
2780  /**
2781  * bits per sample/pixel from the demuxer (needed for huffyuv).
2782  * - encoding: Set by libavcodec.
2783  * - decoding: Set by user.
2784  */
2785  int bits_per_coded_sample;
2786 
2787  /**
2788  * Bits per sample/pixel of internal libavcodec pixel/sample format.
2789  * - encoding: set by user.
2790  * - decoding: set by libavcodec.
2791  */
2792  int bits_per_raw_sample;
2793 
2794 #if FF_API_LOWRES
2795  /**
2796  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2797  * - encoding: unused
2798  * - decoding: Set by user.
2799  */
2800  int lowres;
2801 #endif
2802 
2803 #if FF_API_CODED_FRAME
2804  /**
2805  * the picture in the bitstream
2806  * - encoding: Set by libavcodec.
2807  * - decoding: unused
2808  *
2809  * @deprecated use the quality factor packet side data instead
2810  */
2811  attribute_deprecated AVFrame *coded_frame;
2812 #endif
2813 
2814  /**
2815  * thread count
2816  * is used to decide how many independent tasks should be passed to execute()
2817  * - encoding: Set by user.
2818  * - decoding: Set by user.
2819  */
2820  int thread_count;
2821 
2822  /**
2823  * Which multithreading methods to use.
2824  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2825  * so clients which cannot provide future frames should not use it.
2826  *
2827  * - encoding: Set by user, otherwise the default is used.
2828  * - decoding: Set by user, otherwise the default is used.
2829  */
2830  int thread_type;
2831 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2832 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2833 
2834  /**
2835  * Which multithreading methods are in use by the codec.
2836  * - encoding: Set by libavcodec.
2837  * - decoding: Set by libavcodec.
2838  */
2839  int active_thread_type;
2840 
2841  /**
2842  * Set by the client if its custom get_buffer() callback can be called
2843  * synchronously from another thread, which allows faster multithreaded decoding.
2844  * draw_horiz_band() will be called from other threads regardless of this setting.
2845  * Ignored if the default get_buffer() is used.
2846  * - encoding: Set by user.
2847  * - decoding: Set by user.
2848  */
2849  int thread_safe_callbacks;
2850 
2851  /**
2852  * The codec may call this to execute several independent things.
2853  * It will return only after finishing all tasks.
2854  * The user may replace this with some multithreaded implementation,
2855  * the default implementation will execute the parts serially.
2856  * @param count the number of things to execute
2857  * - encoding: Set by libavcodec, user can override.
2858  * - decoding: Set by libavcodec, user can override.
2859  */
2860  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2861 
2862  /**
2863  * The codec may call this to execute several independent things.
2864  * It will return only after finishing all tasks.
2865  * The user may replace this with some multithreaded implementation,
2866  * the default implementation will execute the parts serially.
2867  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2868  * @param c context passed also to func
2869  * @param count the number of things to execute
2870  * @param arg2 argument passed unchanged to func
2871  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2872  * @param func function that will be called count times, with jobnr from 0 to count-1.
2873  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2874  * two instances of func executing at the same time will have the same threadnr.
2875  * @return always 0 currently, but code should handle a future improvement where when any call to func
2876  * returns < 0 no further calls to func may be done and < 0 is returned.
2877  * - encoding: Set by libavcodec, user can override.
2878  * - decoding: Set by libavcodec, user can override.
2879  */
2880  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2881 
2882  /**
2883  * noise vs. sse weight for the nsse comparison function
2884  * - encoding: Set by user.
2885  * - decoding: unused
2886  */
2887  int nsse_weight;
2888 
2889  /**
2890  * profile
2891  * - encoding: Set by user.
2892  * - decoding: Set by libavcodec.
2893  */
2894  int profile;
2895 #define FF_PROFILE_UNKNOWN -99
2896 #define FF_PROFILE_RESERVED -100
2897 
2898 #define FF_PROFILE_AAC_MAIN 0
2899 #define FF_PROFILE_AAC_LOW 1
2900 #define FF_PROFILE_AAC_SSR 2
2901 #define FF_PROFILE_AAC_LTP 3
2902 #define FF_PROFILE_AAC_HE 4
2903 #define FF_PROFILE_AAC_HE_V2 28
2904 #define FF_PROFILE_AAC_LD 22
2905 #define FF_PROFILE_AAC_ELD 38
2906 #define FF_PROFILE_MPEG2_AAC_LOW 128
2907 #define FF_PROFILE_MPEG2_AAC_HE 131
2908 
2909 #define FF_PROFILE_DNXHD 0
2910 #define FF_PROFILE_DNXHR_LB 1
2911 #define FF_PROFILE_DNXHR_SQ 2
2912 #define FF_PROFILE_DNXHR_HQ 3
2913 #define FF_PROFILE_DNXHR_HQX 4
2914 #define FF_PROFILE_DNXHR_444 5
2915 
2916 #define FF_PROFILE_DTS 20
2917 #define FF_PROFILE_DTS_ES 30
2918 #define FF_PROFILE_DTS_96_24 40
2919 #define FF_PROFILE_DTS_HD_HRA 50
2920 #define FF_PROFILE_DTS_HD_MA 60
2921 #define FF_PROFILE_DTS_EXPRESS 70
2922 
2923 #define FF_PROFILE_MPEG2_422 0
2924 #define FF_PROFILE_MPEG2_HIGH 1
2925 #define FF_PROFILE_MPEG2_SS 2
2926 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2927 #define FF_PROFILE_MPEG2_MAIN 4
2928 #define FF_PROFILE_MPEG2_SIMPLE 5
2929 
2930 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2931 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2932 
2933 #define FF_PROFILE_H264_BASELINE 66
2934 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2935 #define FF_PROFILE_H264_MAIN 77
2936 #define FF_PROFILE_H264_EXTENDED 88
2937 #define FF_PROFILE_H264_HIGH 100
2938 #define FF_PROFILE_H264_HIGH_10 110
2939 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2940 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
2941 #define FF_PROFILE_H264_HIGH_422 122
2942 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2943 #define FF_PROFILE_H264_STEREO_HIGH 128
2944 #define FF_PROFILE_H264_HIGH_444 144
2945 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2946 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2947 #define FF_PROFILE_H264_CAVLC_444 44
2948 
2949 #define FF_PROFILE_VC1_SIMPLE 0
2950 #define FF_PROFILE_VC1_MAIN 1
2951 #define FF_PROFILE_VC1_COMPLEX 2
2952 #define FF_PROFILE_VC1_ADVANCED 3
2953 
2954 #define FF_PROFILE_MPEG4_SIMPLE 0
2955 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2956 #define FF_PROFILE_MPEG4_CORE 2
2957 #define FF_PROFILE_MPEG4_MAIN 3
2958 #define FF_PROFILE_MPEG4_N_BIT 4
2959 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2960 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2961 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2962 #define FF_PROFILE_MPEG4_HYBRID 8
2963 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2964 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2965 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2966 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2967 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2968 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2969 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2970 
2971 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
2972 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
2973 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
2974 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2975 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2976 
2977 #define FF_PROFILE_VP9_0 0
2978 #define FF_PROFILE_VP9_1 1
2979 #define FF_PROFILE_VP9_2 2
2980 #define FF_PROFILE_VP9_3 3
2981 
2982 #define FF_PROFILE_HEVC_MAIN 1
2983 #define FF_PROFILE_HEVC_MAIN_10 2
2984 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2985 #define FF_PROFILE_HEVC_REXT 4
2986 
2987 #define FF_PROFILE_AV1_MAIN 0
2988 #define FF_PROFILE_AV1_HIGH 1
2989 #define FF_PROFILE_AV1_PROFESSIONAL 2
2990 
2991 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
2992 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
2993 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
2994 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
2995 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
2996 
2997 #define FF_PROFILE_SBC_MSBC 1
2998 
2999 #define FF_PROFILE_PRORES_PROXY 0
3000 #define FF_PROFILE_PRORES_LT 1
3001 #define FF_PROFILE_PRORES_STANDARD 2
3002 #define FF_PROFILE_PRORES_HQ 3
3003 #define FF_PROFILE_PRORES_4444 4
3004 #define FF_PROFILE_PRORES_XQ 5
3005 
3006 #define FF_PROFILE_ARIB_PROFILE_A 0
3007 #define FF_PROFILE_ARIB_PROFILE_C 1
3008 
3009  /**
3010  * level
3011  * - encoding: Set by user.
3012  * - decoding: Set by libavcodec.
3013  */
3014  int level;
3015 #define FF_LEVEL_UNKNOWN -99
3016 
3017  /**
3018  * Skip loop filtering for selected frames.
3019  * - encoding: unused
3020  * - decoding: Set by user.
3021  */
3022  enum AVDiscard skip_loop_filter;
3023 
3024  /**
3025  * Skip IDCT/dequantization for selected frames.
3026  * - encoding: unused
3027  * - decoding: Set by user.
3028  */
3029  enum AVDiscard skip_idct;
3030 
3031  /**
3032  * Skip decoding for selected frames.
3033  * - encoding: unused
3034  * - decoding: Set by user.
3035  */
3036  enum AVDiscard skip_frame;
3037 
3038  /**
3039  * Header containing style information for text subtitles.
3040  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
3041  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
3042  * the Format line following. It shouldn't include any Dialogue line.
3043  * - encoding: Set/allocated/freed by user (before avcodec_open2())
3044  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
3045  */
3046  uint8_t *subtitle_header;
3047  int subtitle_header_size;
3048 
3049 #if FF_API_VBV_DELAY
3050  /**
3051  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
3052  * Used for compliant TS muxing.
3053  * - encoding: Set by libavcodec.
3054  * - decoding: unused.
3055  * @deprecated this value is now exported as a part of
3056  * AV_PKT_DATA_CPB_PROPERTIES packet side data
3057  */
3058  attribute_deprecated
3059  uint64_t vbv_delay;
3060 #endif
3061 
3062 #if FF_API_SIDEDATA_ONLY_PKT
3063  /**
3064  * Encoding only and set by default. Allow encoders to output packets
3065  * that do not contain any encoded data, only side data.
3066  *
3067  * Some encoders need to output such packets, e.g. to update some stream
3068  * parameters at the end of encoding.
3069  *
3070  * @deprecated this field disables the default behaviour and
3071  * it is kept only for compatibility.
3072  */
3073  attribute_deprecated
3074  int side_data_only_packets;
3075 #endif
3076 
3077  /**
3078  * Audio only. The number of "priming" samples (padding) inserted by the
3079  * encoder at the beginning of the audio. I.e. this number of leading
3080  * decoded samples must be discarded by the caller to get the original audio
3081  * without leading padding.
3082  *
3083  * - decoding: unused
3084  * - encoding: Set by libavcodec. The timestamps on the output packets are
3085  * adjusted by the encoder so that they always refer to the
3086  * first sample of the data actually contained in the packet,
3087  * including any added padding. E.g. if the timebase is
3088  * 1/samplerate and the timestamp of the first input sample is
3089  * 0, the timestamp of the first output packet will be
3090  * -initial_padding.
3091  */
3092  int initial_padding;
3093 
3094  /**
3095  * - decoding: For codecs that store a framerate value in the compressed
3096  * bitstream, the decoder may export it here. { 0, 1} when
3097  * unknown.
3098  * - encoding: May be used to signal the framerate of CFR content to an
3099  * encoder.
3100  */
3101  AVRational framerate;
3102 
3103  /**
3104  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
3105  * - encoding: unused.
3106  * - decoding: Set by libavcodec before calling get_format()
3107  */
3108  enum AVPixelFormat sw_pix_fmt;
3109 
3110  /**
3111  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3112  * - encoding unused.
3113  * - decoding set by user.
3114  */
3115  AVRational pkt_timebase;
3116 
3117  /**
3118  * AVCodecDescriptor
3119  * - encoding: unused.
3120  * - decoding: set by libavcodec.
3121  */
3122  const AVCodecDescriptor *codec_descriptor;
3123 
3124 #if !FF_API_LOWRES
3125  /**
3126  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3127  * - encoding: unused
3128  * - decoding: Set by user.
3129  */
3130  int lowres;
3131 #endif
3132 
3133  /**
3134  * Current statistics for PTS correction.
3135  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3136  * - encoding: unused
3137  */
3138  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3139  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3140  int64_t pts_correction_last_pts; /// PTS of the last frame
3141  int64_t pts_correction_last_dts; /// DTS of the last frame
3142 
3143  /**
3144  * Character encoding of the input subtitles file.
3145  * - decoding: set by user
3146  * - encoding: unused
3147  */
3148  char *sub_charenc;
3149 
3150  /**
3151  * Subtitles character encoding mode. Formats or codecs might be adjusting
3152  * this setting (if they are doing the conversion themselves for instance).
3153  * - decoding: set by libavcodec
3154  * - encoding: unused
3155  */
3156  int sub_charenc_mode;
3157 #define FF_SUB_CHARENC_MODE_DO_NOTHING -1 ///< do nothing (demuxer outputs a stream supposed to be already in UTF-8, or the codec is bitmap for instance)
3158 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3159 #define FF_SUB_CHARENC_MODE_PRE_DECODER 1 ///< the AVPacket data needs to be recoded to UTF-8 before being fed to the decoder, requires iconv
3160 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
3161 
3162  /**
3163  * Skip processing alpha if supported by codec.
3164  * Note that if the format uses pre-multiplied alpha (common with VP6,
3165  * and recommended due to better video quality/compression)
3166  * the image will look as if alpha-blended onto a black background.
3167  * However for formats that do not use pre-multiplied alpha
3168  * there might be serious artefacts (though e.g. libswscale currently
3169  * assumes pre-multiplied alpha anyway).
3170  *
3171  * - decoding: set by user
3172  * - encoding: unused
3173  */
3174  int skip_alpha;
3175 
3176  /**
3177  * Number of samples to skip after a discontinuity
3178  * - decoding: unused
3179  * - encoding: set by libavcodec
3180  */
3181  int seek_preroll;
3182 
3183 #if !FF_API_DEBUG_MV
3184  /**
3185  * debug motion vectors
3186  * - encoding: Set by user.
3187  * - decoding: Set by user.
3188  */
3189  int debug_mv;
3190 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3191 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3192 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3193 #endif
3194 
3195  /**
3196  * custom intra quantization matrix
3197  * - encoding: Set by user, can be NULL.
3198  * - decoding: unused.
3199  */
3200  uint16_t *chroma_intra_matrix;
3201 
3202  /**
3203  * dump format separator.
3204  * can be ", " or "\n " or anything else
3205  * - encoding: Set by user.
3206  * - decoding: Set by user.
3207  */
3208  uint8_t *dump_separator;
3209 
3210  /**
3211  * ',' separated list of allowed decoders.
3212  * If NULL then all are allowed
3213  * - encoding: unused
3214  * - decoding: set by user
3215  */
3216  char *codec_whitelist;
3217 
3218  /**
3219  * Properties of the stream that gets decoded
3220  * - encoding: unused
3221  * - decoding: set by libavcodec
3222  */
3223  unsigned properties;
3224 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3225 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3226 
3227  /**
3228  * Additional data associated with the entire coded stream.
3229  *
3230  * - decoding: unused
3231  * - encoding: may be set by libavcodec after avcodec_open2().
3232  */
3233  AVPacketSideData *coded_side_data;
3234  int nb_coded_side_data;
3235 
3236  /**
3237  * A reference to the AVHWFramesContext describing the input (for encoding)
3238  * or output (decoding) frames. The reference is set by the caller and
3239  * afterwards owned (and freed) by libavcodec - it should never be read by
3240  * the caller after being set.
3241  *
3242  * - decoding: This field should be set by the caller from the get_format()
3243  * callback. The previous reference (if any) will always be
3244  * unreffed by libavcodec before the get_format() call.
3245  *
3246  * If the default get_buffer2() is used with a hwaccel pixel
3247  * format, then this AVHWFramesContext will be used for
3248  * allocating the frame buffers.
3249  *
3250  * - encoding: For hardware encoders configured to use a hwaccel pixel
3251  * format, this field should be set by the caller to a reference
3252  * to the AVHWFramesContext describing input frames.
3253  * AVHWFramesContext.format must be equal to
3254  * AVCodecContext.pix_fmt.
3255  *
3256  * This field should be set before avcodec_open2() is called.
3257  */
3258  AVBufferRef *hw_frames_ctx;
3259 
3260  /**
3261  * Control the form of AVSubtitle.rects[N]->ass
3262  * - decoding: set by user
3263  * - encoding: unused
3264  */
3265  int sub_text_format;
3266 #define FF_SUB_TEXT_FMT_ASS 0
3267 #if FF_API_ASS_TIMING
3268 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3269 #endif
3270 
3271  /**
3272  * Audio only. The amount of padding (in samples) appended by the encoder to
3273  * the end of the audio. I.e. this number of decoded samples must be
3274  * discarded by the caller from the end of the stream to get the original
3275  * audio without any trailing padding.
3276  *
3277  * - decoding: unused
3278  * - encoding: unused
3279  */
3280  int trailing_padding;
3281 
3282  /**
3283  * The number of pixels per image to maximally accept.
3284  *
3285  * - decoding: set by user
3286  * - encoding: set by user
3287  */
3288  int64_t max_pixels;
3289 
3290  /**
3291  * A reference to the AVHWDeviceContext describing the device which will
3292  * be used by a hardware encoder/decoder. The reference is set by the
3293  * caller and afterwards owned (and freed) by libavcodec.
3294  *
3295  * This should be used if either the codec device does not require
3296  * hardware frames or any that are used are to be allocated internally by
3297  * libavcodec. If the user wishes to supply any of the frames used as
3298  * encoder input or decoder output then hw_frames_ctx should be used
3299  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3300  * field will be ignored while decoding the associated stream segment, but
3301  * may again be used on a following one after another get_format() call.
3302  *
3303  * For both encoders and decoders this field should be set before
3304  * avcodec_open2() is called and must not be written to thereafter.
3305  *
3306  * Note that some decoders may require this field to be set initially in
3307  * order to support hw_frames_ctx at all - in that case, all frames
3308  * contexts used must be created on the same device.
3309  */
3310  AVBufferRef *hw_device_ctx;
3311 
3312  /**
3313  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3314  * decoding (if active).
3315  * - encoding: unused
3316  * - decoding: Set by user (either before avcodec_open2(), or in the
3317  * AVCodecContext.get_format callback)
3318  */
3319  int hwaccel_flags;
3320 
3321  /**
3322  * Video decoding only. Certain video codecs support cropping, meaning that
3323  * only a sub-rectangle of the decoded frame is intended for display. This
3324  * option controls how cropping is handled by libavcodec.
3325  *
3326  * When set to 1 (the default), libavcodec will apply cropping internally.
3327  * I.e. it will modify the output frame width/height fields and offset the
3328  * data pointers (only by as much as possible while preserving alignment, or
3329  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
3330  * the frames output by the decoder refer only to the cropped area. The
3331  * crop_* fields of the output frames will be zero.
3332  *
3333  * When set to 0, the width/height fields of the output frames will be set
3334  * to the coded dimensions and the crop_* fields will describe the cropping
3335  * rectangle. Applying the cropping is left to the caller.
3336  *
3337  * @warning When hardware acceleration with opaque output frames is used,
3338  * libavcodec is unable to apply cropping from the top/left border.
3339  *
3340  * @note when this option is set to zero, the width/height fields of the
3341  * AVCodecContext and output AVFrames have different meanings. The codec
3342  * context fields store display dimensions (with the coded dimensions in
3343  * coded_width/height), while the frame fields store the coded dimensions
3344  * (with the display dimensions being determined by the crop_* fields).
3345  */
3346  int apply_cropping;
3347 
3348  /*
3349  * Video decoding only. Sets the number of extra hardware frames which
3350  * the decoder will allocate for use by the caller. This must be set
3351  * before avcodec_open2() is called.
3352  *
3353  * Some hardware decoders require all frames that they will use for
3354  * output to be defined in advance before decoding starts. For such
3355  * decoders, the hardware frame pool must therefore be of a fixed size.
3356  * The extra frames set here are on top of any number that the decoder
3357  * needs internally in order to operate normally (for example, frames
3358  * used as reference pictures).
3359  */
3360  int extra_hw_frames;
3361 
3362  /**
3363  * The percentage of damaged samples to discard a frame.
3364  *
3365  * - decoding: set by user
3366  * - encoding: unused
3367  */
3368  int discard_damaged_percentage;
3369 } AVCodecContext;
3370 
3371 #if FF_API_CODEC_GET_SET
3372 /**
3373  * Accessors for some AVCodecContext fields. These used to be provided for ABI
3374  * compatibility, and do not need to be used anymore.
3375  */
3376 attribute_deprecated
3377 AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
3378 attribute_deprecated
3379 void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
3380 
3381 attribute_deprecated
3382 const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
3383 attribute_deprecated
3384 void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
3385 
3386 attribute_deprecated
3387 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3388 
3389 #if FF_API_LOWRES
3390 attribute_deprecated
3391 int av_codec_get_lowres(const AVCodecContext *avctx);
3392 attribute_deprecated
3393 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3394 #endif
3395 
3396 attribute_deprecated
3397 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3398 attribute_deprecated
3399 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3400 
3401 attribute_deprecated
3402 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3403 attribute_deprecated
3404 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3405 #endif
3406 
3407 /**
3408  * AVProfile.
3409  */
3410 typedef struct AVProfile {
3411  int profile;
3412  const char *name; ///< short name for the profile
3413 } AVProfile;
3414 
3415 enum {
3416  /**
3417  * The codec supports this format via the hw_device_ctx interface.
3418  *
3419  * When selecting this format, AVCodecContext.hw_device_ctx should
3420  * have been set to a device of the specified type before calling
3421  * avcodec_open2().
3422  */
3423  AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX = 0x01,
3424  /**
3425  * The codec supports this format via the hw_frames_ctx interface.
3426  *
3427  * When selecting this format for a decoder,
3428  * AVCodecContext.hw_frames_ctx should be set to a suitable frames
3429  * context inside the get_format() callback. The frames context
3430  * must have been created on a device of the specified type.
3431  */
3432  AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX = 0x02,
3433  /**
3434  * The codec supports this format by some internal method.
3435  *
3436  * This format can be selected without any additional configuration -
3437  * no device or frames context is required.
3438  */
3439  AV_CODEC_HW_CONFIG_METHOD_INTERNAL = 0x04,
3440  /**
3441  * The codec supports this format by some ad-hoc method.
3442  *
3443  * Additional settings and/or function calls are required. See the
3444  * codec-specific documentation for details. (Methods requiring
3445  * this sort of configuration are deprecated and others should be
3446  * used in preference.)
3447  */
3448  AV_CODEC_HW_CONFIG_METHOD_AD_HOC = 0x08,
3449 };
3450 
3451 typedef struct AVCodecHWConfig {
3452  /**
3453  * A hardware pixel format which the codec can use.
3454  */
3455  enum AVPixelFormat pix_fmt;
3456  /**
3457  * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
3458  * setup methods which can be used with this configuration.
3459  */
3460  int methods;
3461  /**
3462  * The device type associated with the configuration.
3463  *
3464  * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
3465  * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
3466  */
3467  enum AVHWDeviceType device_type;
3468 } AVCodecHWConfig;
3469 
3470 typedef struct AVCodecDefault AVCodecDefault;
3471 
3472 struct AVSubtitle;
3473 
3474 /**
3475  * AVCodec.
3476  */
3477 typedef struct AVCodec {
3478  /**
3479  * Name of the codec implementation.
3480  * The name is globally unique among encoders and among decoders (but an
3481  * encoder and a decoder can share the same name).
3482  * This is the primary way to find a codec from the user perspective.
3483  */
3484  const char *name;
3485  /**
3486  * Descriptive name for the codec, meant to be more human readable than name.
3487  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3488  */
3489  const char *long_name;
3490  enum AVMediaType type;
3491  enum AVCodecID id;
3492  /**
3493  * Codec capabilities.
3494  * see AV_CODEC_CAP_*
3495  */
3496  int capabilities;
3497  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3498  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3499  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3500  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3501  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3502  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3503  const AVClass *priv_class; ///< AVClass for the private context
3504  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3505 
3506  /**
3507  * Group name of the codec implementation.
3508  * This is a short symbolic name of the wrapper backing this codec. A
3509  * wrapper uses some kind of external implementation for the codec, such
3510  * as an external library, or a codec implementation provided by the OS or
3511  * the hardware.
3512  * If this field is NULL, this is a builtin, libavcodec native codec.
3513  * If non-NULL, this will be the suffix in AVCodec.name in most cases
3514  * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
3515  */
3516  const char *wrapper_name;
3517 
3518  /*****************************************************************
3519  * No fields below this line are part of the public API. They
3520  * may not be used outside of libavcodec and can be changed and
3521  * removed at will.
3522  * New public fields should be added right above.
3523  *****************************************************************
3524  */
3525  int priv_data_size;
3526  struct AVCodec *next;
3527  /**
3528  * @name Frame-level threading support functions
3529  * @{
3530  */
3531  /**
3532  * If defined, called on thread contexts when they are created.
3533  * If the codec allocates writable tables in init(), re-allocate them here.
3534  * priv_data will be set to a copy of the original.
3535  */
3536  int (*init_thread_copy)(AVCodecContext *);
3537  /**
3538  * Copy necessary context variables from a previous thread context to the current one.
3539  * If not defined, the next thread will start automatically; otherwise, the codec
3540  * must call ff_thread_finish_setup().
3541  *
3542  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3543  */
3544  int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
3545  /** @} */
3546 
3547  /**
3548  * Private codec-specific defaults.
3549  */
3550  const AVCodecDefault *defaults;
3551 
3552  /**
3553  * Initialize codec static data, called from avcodec_register().
3554  *
3555  * This is not intended for time consuming operations as it is
3556  * run for every codec regardless of that codec being used.
3557  */
3558  void (*init_static_data)(struct AVCodec *codec);
3559 
3560  int (*init)(AVCodecContext *);
3561  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3562  const struct AVSubtitle *sub);
3563  /**
3564  * Encode data to an AVPacket.
3565  *
3566  * @param avctx codec context
3567  * @param avpkt output AVPacket (may contain a user-provided buffer)
3568  * @param[in] frame AVFrame containing the raw data to be encoded
3569  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3570  * non-empty packet was returned in avpkt.
3571  * @return 0 on success, negative error code on failure
3572  */
3573  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3574  int *got_packet_ptr);
3575  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3576  int (*close)(AVCodecContext *);
3577  /**
3578  * Encode API with decoupled packet/frame dataflow. The API is the
3579  * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3580  * that:
3581  * - never called if the codec is closed or the wrong type,
3582  * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3583  * - only one drain frame is ever passed down,
3584  */
3585  int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
3586  int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
3587 
3588  /**
3589  * Decode API with decoupled packet/frame dataflow. This function is called
3590  * to get one output frame. It should call ff_decode_get_packet() to obtain
3591  * input data.
3592  */
3593  int (*receive_frame)(AVCodecContext *avctx, AVFrame *frame);
3594  /**
3595  * Flush buffers.
3596  * Will be called when seeking
3597  */
3598  void (*flush)(AVCodecContext *);
3599  /**
3600  * Internal codec capabilities.
3601  * See FF_CODEC_CAP_* in internal.h
3602  */
3603  int caps_internal;
3604 
3605  /**
3606  * Decoding only, a comma-separated list of bitstream filters to apply to
3607  * packets before decoding.
3608  */
3609  const char *bsfs;
3610 
3611  /**
3612  * Array of pointers to hardware configurations supported by the codec,
3613  * or NULL if no hardware supported. The array is terminated by a NULL
3614  * pointer.
3615  *
3616  * The user can only access this field via avcodec_get_hw_config().
3617  */
3618  const struct AVCodecHWConfigInternal **hw_configs;
3619 } AVCodec;
3620 
3621 #if FF_API_CODEC_GET_SET
3622 attribute_deprecated
3623 int av_codec_get_max_lowres(const AVCodec *codec);
3624 #endif
3625 
3626 struct MpegEncContext;
3627 
3628 /**
3629  * Retrieve supported hardware configurations for a codec.
3630  *
3631  * Values of index from zero to some maximum return the indexed configuration
3632  * descriptor; all other values return NULL. If the codec does not support
3633  * any hardware configurations then it will always return NULL.
3634  */
3635 const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
3636 
3637 /**
3638  * @defgroup lavc_hwaccel AVHWAccel
3639  *
3640  * @note Nothing in this structure should be accessed by the user. At some
3641  * point in future it will not be externally visible at all.
3642  *
3643  * @{
3644  */
3645 typedef struct AVHWAccel {
3646  /**
3647  * Name of the hardware accelerated codec.
3648  * The name is globally unique among encoders and among decoders (but an
3649  * encoder and a decoder can share the same name).
3650  */
3651  const char *name;
3652 
3653  /**
3654  * Type of codec implemented by the hardware accelerator.
3655  *
3656  * See AVMEDIA_TYPE_xxx
3657  */
3658  enum AVMediaType type;
3659 
3660  /**
3661  * Codec implemented by the hardware accelerator.
3662  *
3663  * See AV_CODEC_ID_xxx
3664  */
3665  enum AVCodecID id;
3666 
3667  /**
3668  * Supported pixel format.
3669  *
3670  * Only hardware accelerated formats are supported here.
3671  */
3672  enum AVPixelFormat pix_fmt;
3673 
3674  /**
3675  * Hardware accelerated codec capabilities.
3676  * see AV_HWACCEL_CODEC_CAP_*
3677  */
3678  int capabilities;
3679 
3680  /*****************************************************************
3681  * No fields below this line are part of the public API. They
3682  * may not be used outside of libavcodec and can be changed and
3683  * removed at will.
3684  * New public fields should be added right above.
3685  *****************************************************************
3686  */
3687 
3688  /**
3689  * Allocate a custom buffer
3690  */
3691  int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
3692 
3693  /**
3694  * Called at the beginning of each frame or field picture.
3695  *
3696  * Meaningful frame information (codec specific) is guaranteed to
3697  * be parsed at this point. This function is mandatory.
3698  *
3699  * Note that buf can be NULL along with buf_size set to 0.
3700  * Otherwise, this means the whole frame is available at this point.
3701  *
3702  * @param avctx the codec context
3703  * @param buf the frame data buffer base
3704  * @param buf_size the size of the frame in bytes
3705  * @return zero if successful, a negative value otherwise
3706  */
3707  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3708 
3709  /**
3710  * Callback for parameter data (SPS/PPS/VPS etc).
3711  *
3712  * Useful for hardware decoders which keep persistent state about the
3713  * video parameters, and need to receive any changes to update that state.
3714  *
3715  * @param avctx the codec context
3716  * @param type the nal unit type
3717  * @param buf the nal unit data buffer
3718  * @param buf_size the size of the nal unit in bytes
3719  * @return zero if successful, a negative value otherwise
3720  */
3721  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
3722 
3723  /**
3724  * Callback for each slice.
3725  *
3726  * Meaningful slice information (codec specific) is guaranteed to
3727  * be parsed at this point. This function is mandatory.
3728  * The only exception is XvMC, that works on MB level.
3729  *
3730  * @param avctx the codec context
3731  * @param buf the slice data buffer base
3732  * @param buf_size the size of the slice in bytes
3733  * @return zero if successful, a negative value otherwise
3734  */
3735  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3736 
3737  /**
3738  * Called at the end of each frame or field picture.
3739  *
3740  * The whole picture is parsed at this point and can now be sent
3741  * to the hardware accelerator. This function is mandatory.
3742  *
3743  * @param avctx the codec context
3744  * @return zero if successful, a negative value otherwise
3745  */
3746  int (*end_frame)(AVCodecContext *avctx);
3747 
3748  /**
3749  * Size of per-frame hardware accelerator private data.
3750  *
3751  * Private data is allocated with av_mallocz() before
3752  * AVCodecContext.get_buffer() and deallocated after
3753  * AVCodecContext.release_buffer().
3754  */
3755  int frame_priv_data_size;
3756 
3757  /**
3758  * Called for every Macroblock in a slice.
3759  *
3760  * XvMC uses it to replace the ff_mpv_reconstruct_mb().
3761  * Instead of decoding to raw picture, MB parameters are
3762  * stored in an array provided by the video driver.
3763  *
3764  * @param s the mpeg context
3765  */
3766  void (*decode_mb)(struct MpegEncContext *s);
3767 
3768  /**
3769  * Initialize the hwaccel private data.
3770  *
3771  * This will be called from ff_get_format(), after hwaccel and
3772  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3773  * is allocated.
3774  */
3775  int (*init)(AVCodecContext *avctx);
3776 
3777  /**
3778  * Uninitialize the hwaccel private data.
3779  *
3780  * This will be called from get_format() or avcodec_close(), after hwaccel
3781  * and hwaccel_context are already uninitialized.
3782  */
3783  int (*uninit)(AVCodecContext *avctx);
3784 
3785  /**
3786  * Size of the private data to allocate in
3787  * AVCodecInternal.hwaccel_priv_data.
3788  */
3789  int priv_data_size;
3790 
3791  /**
3792  * Internal hwaccel capabilities.
3793  */
3794  int caps_internal;
3795 
3796  /**
3797  * Fill the given hw_frames context with current codec parameters. Called
3798  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
3799  * details.
3800  *
3801  * This CAN be called before AVHWAccel.init is called, and you must assume
3802  * that avctx->hwaccel_priv_data is invalid.
3803  */
3804  int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
3805 } AVHWAccel;
3806 
3807 /**
3808  * HWAccel is experimental and is thus avoided in favor of non experimental
3809  * codecs
3810  */
3811 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
3812 
3813 /**
3814  * Hardware acceleration should be used for decoding even if the codec level
3815  * used is unknown or higher than the maximum supported level reported by the
3816  * hardware driver.
3817  *
3818  * It's generally a good idea to pass this flag unless you have a specific
3819  * reason not to, as hardware tends to under-report supported levels.
3820  */
3821 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3822 
3823 /**
3824  * Hardware acceleration can output YUV pixel formats with a different chroma
3825  * sampling than 4:2:0 and/or other than 8 bits per component.
3826  */
3827 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3828 
3829 /**
3830  * Hardware acceleration should still be attempted for decoding when the
3831  * codec profile does not match the reported capabilities of the hardware.
3832  *
3833  * For example, this can be used to try to decode baseline profile H.264
3834  * streams in hardware - it will often succeed, because many streams marked
3835  * as baseline profile actually conform to constrained baseline profile.
3836  *
3837  * @warning If the stream is actually not supported then the behaviour is
3838  * undefined, and may include returning entirely incorrect output
3839  * while indicating success.
3840  */
3841 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
3842 
3843 /**
3844  * @}
3845  */
3846 
3847 #if FF_API_AVPICTURE
3848 /**
3849  * @defgroup lavc_picture AVPicture
3850  *
3851  * Functions for working with AVPicture
3852  * @{
3853  */
3854 
3855 /**
3856  * Picture data structure.
3857  *
3858  * Up to four components can be stored into it, the last component is
3859  * alpha.
3860  * @deprecated use AVFrame or imgutils functions instead
3861  */
3862 typedef struct AVPicture {
3863  attribute_deprecated
3864  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3865  attribute_deprecated
3866  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3867 } AVPicture;
3868 
3869 /**
3870  * @}
3871  */
3872 #endif
3873 
3874 enum AVSubtitleType {
3875  SUBTITLE_NONE,
3876 
3877  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3878 
3879  /**
3880  * Plain text, the text field must be set by the decoder and is
3881  * authoritative. ass and pict fields may contain approximations.
3882  */
3883  SUBTITLE_TEXT,
3884 
3885  /**
3886  * Formatted text, the ass field must be set by the decoder and is
3887  * authoritative. pict and text fields may contain approximations.
3888  */
3889  SUBTITLE_ASS,
3890 };
3891 
3892 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3893 
3894 typedef struct AVSubtitleRect {
3895  int x; ///< top left corner of pict, undefined when pict is not set
3896  int y; ///< top left corner of pict, undefined when pict is not set
3897  int w; ///< width of pict, undefined when pict is not set
3898  int h; ///< height of pict, undefined when pict is not set
3899  int nb_colors; ///< number of colors in pict, undefined when pict is not set
3900 
3901 #if FF_API_AVPICTURE
3902  /**
3903  * @deprecated unused
3904  */
3905  attribute_deprecated
3906  AVPicture pict;
3907 #endif
3908  /**
3909  * data+linesize for the bitmap of this subtitle.
3910  * Can be set for text/ass as well once they are rendered.
3911  */
3912  uint8_t *data[4];
3913  int linesize[4];
3914 
3915  enum AVSubtitleType type;
3916 
3917  char *text; ///< 0 terminated plain UTF-8 text
3918 
3919  /**
3920  * 0 terminated ASS/SSA compatible event line.
3921  * The presentation of this is unaffected by the other values in this
3922  * struct.
3923  */
3924  char *ass;
3925 
3926  int flags;
3927 } AVSubtitleRect;
3928 
3929 typedef struct AVSubtitle {
3930  uint16_t format; /* 0 = graphics */
3931  uint32_t start_display_time; /* relative to packet pts, in ms */
3932  uint32_t end_display_time; /* relative to packet pts, in ms */
3933  unsigned num_rects;
3934  AVSubtitleRect **rects;
3935  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3936 } AVSubtitle;
3937 
3938 /**
3939  * This struct describes the properties of an encoded stream.
3940  *
3941  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3942  * be allocated with avcodec_parameters_alloc() and freed with
3943  * avcodec_parameters_free().
3944  */
3945 typedef struct AVCodecParameters {
3946  /**
3947  * General type of the encoded data.
3948  */
3949  enum AVMediaType codec_type;
3950  /**
3951  * Specific type of the encoded data (the codec used).
3952  */
3953  enum AVCodecID codec_id;
3954  /**
3955  * Additional information about the codec (corresponds to the AVI FOURCC).
3956  */
3957  uint32_t codec_tag;
3958 
3959  /**
3960  * Extra binary data needed for initializing the decoder, codec-dependent.
3961  *
3962  * Must be allocated with av_malloc() and will be freed by
3963  * avcodec_parameters_free(). The allocated size of extradata must be at
3964  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3965  * bytes zeroed.
3966  */
3967  uint8_t *extradata;
3968  /**
3969  * Size of the extradata content in bytes.
3970  */
3971  int extradata_size;
3972 
3973  /**
3974  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3975  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3976  */
3977  int format;
3978 
3979  /**
3980  * The average bitrate of the encoded data (in bits per second).
3981  */
3982  int64_t bit_rate;
3983 
3984  /**
3985  * The number of bits per sample in the codedwords.
3986  *
3987  * This is basically the bitrate per sample. It is mandatory for a bunch of
3988  * formats to actually decode them. It's the number of bits for one sample in
3989  * the actual coded bitstream.
3990  *
3991  * This could be for example 4 for ADPCM
3992  * For PCM formats this matches bits_per_raw_sample
3993  * Can be 0
3994  */
3995  int bits_per_coded_sample;
3996 
3997  /**
3998  * This is the number of valid bits in each output sample. If the
3999  * sample format has more bits, the least significant bits are additional
4000  * padding bits, which are always 0. Use right shifts to reduce the sample
4001  * to its actual size. For example, audio formats with 24 bit samples will
4002  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
4003  * To get the original sample use "(int32_t)sample >> 8"."
4004  *
4005  * For ADPCM this might be 12 or 16 or similar
4006  * Can be 0
4007  */
4008  int bits_per_raw_sample;
4009 
4010  /**
4011  * Codec-specific bitstream restrictions that the stream conforms to.
4012  */
4013  int profile;
4014  int level;
4015 
4016  /**
4017  * Video only. The dimensions of the video frame in pixels.
4018  */
4019  int width;
4020  int height;
4021 
4022  /**
4023  * Video only. The aspect ratio (width / height) which a single pixel
4024  * should have when displayed.
4025  *
4026  * When the aspect ratio is unknown / undefined, the numerator should be
4027  * set to 0 (the denominator may have any value).
4028  */
4029  AVRational sample_aspect_ratio;
4030 
4031  /**
4032  * Video only. The order of the fields in interlaced video.
4033  */
4034  enum AVFieldOrder field_order;
4035 
4036  /**
4037  * Video only. Additional colorspace characteristics.
4038  */
4039  enum AVColorRange color_range;
4040  enum AVColorPrimaries color_primaries;
4041  enum AVColorTransferCharacteristic color_trc;
4042  enum AVColorSpace color_space;
4043  enum AVChromaLocation chroma_location;
4044 
4045  /**
4046  * Video only. Number of delayed frames.
4047  */
4048  int video_delay;
4049 
4050  /**
4051  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
4052  * unknown or unspecified, otherwise the number of bits set must be equal to
4053  * the channels field.
4054  */
4055  uint64_t channel_layout;
4056  /**
4057  * Audio only. The number of audio channels.
4058  */
4059  int channels;
4060  /**
4061  * Audio only. The number of audio samples per second.
4062  */
4063  int sample_rate;
4064  /**
4065  * Audio only. The number of bytes per coded audio frame, required by some
4066  * formats.
4067  *
4068  * Corresponds to nBlockAlign in WAVEFORMATEX.
4069  */
4070  int block_align;
4071  /**
4072  * Audio only. Audio frame size, if known. Required by some formats to be static.
4073  */
4074  int frame_size;
4075 
4076  /**
4077  * Audio only. The amount of padding (in samples) inserted by the encoder at
4078  * the beginning of the audio. I.e. this number of leading decoded samples
4079  * must be discarded by the caller to get the original audio without leading
4080  * padding.
4081  */
4082  int initial_padding;
4083  /**
4084  * Audio only. The amount of padding (in samples) appended by the encoder to
4085  * the end of the audio. I.e. this number of decoded samples must be
4086  * discarded by the caller from the end of the stream to get the original
4087  * audio without any trailing padding.
4088  */
4089  int trailing_padding;
4090  /**
4091  * Audio only. Number of samples to skip after a discontinuity.
4092  */
4093  int seek_preroll;
4094 } AVCodecParameters;
4095 
4096 /**
4097  * Iterate over all registered codecs.
4098  *
4099  * @param opaque a pointer where libavcodec will store the iteration state. Must
4100  * point to NULL to start the iteration.
4101  *
4102  * @return the next registered codec or NULL when the iteration is
4103  * finished
4104  */
4105 const AVCodec *av_codec_iterate(void **opaque);
4106 
4107 #if FF_API_NEXT
4108 /**
4109  * If c is NULL, returns the first registered codec,
4110  * if c is non-NULL, returns the next registered codec after c,
4111  * or NULL if c is the last one.
4112  */
4113 attribute_deprecated
4114 AVCodec *av_codec_next(const AVCodec *c);
4115 #endif
4116 
4117 /**
4118  * Return the LIBAVCODEC_VERSION_INT constant.
4119  */
4120 unsigned avcodec_version(void);
4121 
4122 /**
4123  * Return the libavcodec build-time configuration.
4124  */
4125 const char *avcodec_configuration(void);
4126 
4127 /**
4128  * Return the libavcodec license.
4129  */
4130 const char *avcodec_license(void);
4131 
4132 #if FF_API_NEXT
4133 /**
4134  * Register the codec codec and initialize libavcodec.
4135  *
4136  * @warning either this function or avcodec_register_all() must be called
4137  * before any other libavcodec functions.
4138  *
4139  * @see avcodec_register_all()
4140  */
4141 attribute_deprecated
4142 void avcodec_register(AVCodec *codec);
4143 
4144 /**
4145  * Register all the codecs, parsers and bitstream filters which were enabled at
4146  * configuration time. If you do not call this function you can select exactly
4147  * which formats you want to support, by using the individual registration
4148  * functions.
4149  *
4150  * @see avcodec_register
4151  * @see av_register_codec_parser
4152  * @see av_register_bitstream_filter
4153  */
4154 attribute_deprecated
4155 void avcodec_register_all(void);
4156 #endif
4157 
4158 /**
4159  * Allocate an AVCodecContext and set its fields to default values. The
4160  * resulting struct should be freed with avcodec_free_context().
4161  *
4162  * @param codec if non-NULL, allocate private data and initialize defaults
4163  * for the given codec. It is illegal to then call avcodec_open2()
4164  * with a different codec.
4165  * If NULL, then the codec-specific defaults won't be initialized,
4166  * which may result in suboptimal default settings (this is
4167  * important mainly for encoders, e.g. libx264).
4168  *
4169  * @return An AVCodecContext filled with default values or NULL on failure.
4170  */
4171 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
4172 
4173 /**
4174  * Free the codec context and everything associated with it and write NULL to
4175  * the provided pointer.
4176  */
4177 void avcodec_free_context(AVCodecContext **avctx);
4178 
4179 #if FF_API_GET_CONTEXT_DEFAULTS
4180 /**
4181  * @deprecated This function should not be used, as closing and opening a codec
4182  * context multiple time is not supported. A new codec context should be
4183  * allocated for each new use.
4184  */
4185 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
4186 #endif
4187 
4188 /**
4189  * Get the AVClass for AVCodecContext. It can be used in combination with
4190  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4191  *
4192  * @see av_opt_find().
4193  */
4194 const AVClass *avcodec_get_class(void);
4195 
4196 #if FF_API_COPY_CONTEXT
4197 /**
4198  * Get the AVClass for AVFrame. It can be used in combination with
4199  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4200  *
4201  * @see av_opt_find().
4202  */
4203 const AVClass *avcodec_get_frame_class(void);
4204 
4205 /**
4206  * Get the AVClass for AVSubtitleRect. It can be used in combination with
4207  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4208  *
4209  * @see av_opt_find().
4210  */
4211 const AVClass *avcodec_get_subtitle_rect_class(void);
4212 
4213 /**
4214  * Copy the settings of the source AVCodecContext into the destination
4215  * AVCodecContext. The resulting destination codec context will be
4216  * unopened, i.e. you are required to call avcodec_open2() before you
4217  * can use this AVCodecContext to decode/encode video/audio data.
4218  *
4219  * @param dest target codec context, should be initialized with
4220  * avcodec_alloc_context3(NULL), but otherwise uninitialized
4221  * @param src source codec context
4222  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4223  *
4224  * @deprecated The semantics of this function are ill-defined and it should not
4225  * be used. If you need to transfer the stream parameters from one codec context
4226  * to another, use an intermediate AVCodecParameters instance and the
4227  * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4228  * functions.
4229  */
4230 attribute_deprecated
4231 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
4232 #endif
4233 
4234 /**
4235  * Allocate a new AVCodecParameters and set its fields to default values
4236  * (unknown/invalid/0). The returned struct must be freed with
4237  * avcodec_parameters_free().
4238  */
4239 AVCodecParameters *avcodec_parameters_alloc(void);
4240 
4241 /**
4242  * Free an AVCodecParameters instance and everything associated with it and
4243  * write NULL to the supplied pointer.
4244  */
4245 void avcodec_parameters_free(AVCodecParameters **par);
4246 
4247 /**
4248  * Copy the contents of src to dst. Any allocated fields in dst are freed and
4249  * replaced with newly allocated duplicates of the corresponding fields in src.
4250  *
4251  * @return >= 0 on success, a negative AVERROR code on failure.
4252  */
4253 int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src);
4254 
4255 /**
4256  * Fill the parameters struct based on the values from the supplied codec
4257  * context. Any allocated fields in par are freed and replaced with duplicates
4258  * of the corresponding fields in codec.
4259  *
4260  * @return >= 0 on success, a negative AVERROR code on failure
4261  */
4262 int avcodec_parameters_from_context(AVCodecParameters *par,
4263  const AVCodecContext *codec);
4264 
4265 /**
4266  * Fill the codec context based on the values from the supplied codec
4267  * parameters. Any allocated fields in codec that have a corresponding field in
4268  * par are freed and replaced with duplicates of the corresponding field in par.
4269  * Fields in codec that do not have a counterpart in par are not touched.
4270  *
4271  * @return >= 0 on success, a negative AVERROR code on failure.
4272  */
4273 int avcodec_parameters_to_context(AVCodecContext *codec,
4274  const AVCodecParameters *par);
4275 
4276 /**
4277  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4278  * function the context has to be allocated with avcodec_alloc_context3().
4279  *
4280  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4281  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4282  * retrieving a codec.
4283  *
4284  * @warning This function is not thread safe!
4285  *
4286  * @note Always call this function before using decoding routines (such as
4287  * @ref avcodec_receive_frame()).
4288  *
4289  * @code
4290  * avcodec_register_all();
4291  * av_dict_set(&opts, "b", "2.5M", 0);
4292  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4293  * if (!codec)
4294  * exit(1);
4295  *
4296  * context = avcodec_alloc_context3(codec);
4297  *
4298  * if (avcodec_open2(context, codec, opts) < 0)
4299  * exit(1);
4300  * @endcode
4301  *
4302  * @param avctx The context to initialize.
4303  * @param codec The codec to open this context for. If a non-NULL codec has been
4304  * previously passed to avcodec_alloc_context3() or
4305  * for this context, then this parameter MUST be either NULL or
4306  * equal to the previously passed codec.
4307  * @param options A dictionary filled with AVCodecContext and codec-private options.
4308  * On return this object will be filled with options that were not found.
4309  *
4310  * @return zero on success, a negative value on error
4311  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4312  * av_dict_set(), av_opt_find().
4313  */
4314 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4315 
4316 /**
4317  * Close a given AVCodecContext and free all the data associated with it
4318  * (but not the AVCodecContext itself).
4319  *
4320  * Calling this function on an AVCodecContext that hasn't been opened will free
4321  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4322  * codec. Subsequent calls will do nothing.
4323  *
4324  * @note Do not use this function. Use avcodec_free_context() to destroy a
4325  * codec context (either open or closed). Opening and closing a codec context
4326  * multiple times is not supported anymore -- use multiple codec contexts
4327  * instead.
4328  */
4329 int avcodec_close(AVCodecContext *avctx);
4330 
4331 /**
4332  * Free all allocated data in the given subtitle struct.
4333  *
4334  * @param sub AVSubtitle to free.
4335  */
4336 void avsubtitle_free(AVSubtitle *sub);
4337 
4338 /**
4339  * @}
4340  */
4341 
4342 /**
4343  * @addtogroup lavc_packet
4344  * @{
4345  */
4346 
4347 /**
4348  * Allocate an AVPacket and set its fields to default values. The resulting
4349  * struct must be freed using av_packet_free().
4350  *
4351  * @return An AVPacket filled with default values or NULL on failure.
4352  *
4353  * @note this only allocates the AVPacket itself, not the data buffers. Those
4354  * must be allocated through other means such as av_new_packet.
4355  *
4356  * @see av_new_packet
4357  */
4358 AVPacket *av_packet_alloc(void);
4359 
4360 /**
4361  * Create a new packet that references the same data as src.
4362  *
4363  * This is a shortcut for av_packet_alloc()+av_packet_ref().
4364  *
4365  * @return newly created AVPacket on success, NULL on error.
4366  *
4367  * @see av_packet_alloc
4368  * @see av_packet_ref
4369  */
4370 AVPacket *av_packet_clone(const AVPacket *src);
4371 
4372 /**
4373  * Free the packet, if the packet is reference counted, it will be
4374  * unreferenced first.
4375  *
4376  * @param pkt packet to be freed. The pointer will be set to NULL.
4377  * @note passing NULL is a no-op.
4378  */
4379 void av_packet_free(AVPacket **pkt);
4380 
4381 /**
4382  * Initialize optional fields of a packet with default values.
4383  *
4384  * Note, this does not touch the data and size members, which have to be
4385  * initialized separately.
4386  *
4387  * @param pkt packet
4388  */
4389 void av_init_packet(AVPacket *pkt);
4390 
4391 /**
4392  * Allocate the payload of a packet and initialize its fields with
4393  * default values.
4394  *
4395  * @param pkt packet
4396  * @param size wanted payload size
4397  * @return 0 if OK, AVERROR_xxx otherwise
4398  */
4399 int av_new_packet(AVPacket *pkt, int size);
4400 
4401 /**
4402  * Reduce packet size, correctly zeroing padding
4403  *
4404  * @param pkt packet
4405  * @param size new size
4406  */
4407 void av_shrink_packet(AVPacket *pkt, int size);
4408 
4409 /**
4410  * Increase packet size, correctly zeroing padding
4411  *
4412  * @param pkt packet
4413  * @param grow_by number of bytes by which to increase the size of the packet
4414  */
4415 int av_grow_packet(AVPacket *pkt, int grow_by);
4416 
4417 /**
4418  * Initialize a reference-counted packet from av_malloc()ed data.
4419  *
4420  * @param pkt packet to be initialized. This function will set the data, size,
4421  * buf and destruct fields, all others are left untouched.
4422  * @param data Data allocated by av_malloc() to be used as packet data. If this
4423  * function returns successfully, the data is owned by the underlying AVBuffer.
4424  * The caller may not access the data through other means.
4425  * @param size size of data in bytes, without the padding. I.e. the full buffer
4426  * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4427  *
4428  * @return 0 on success, a negative AVERROR on error
4429  */
4430 int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
4431 
4432 #if FF_API_AVPACKET_OLD_API
4433 /**
4434  * @warning This is a hack - the packet memory allocation stuff is broken. The
4435  * packet is allocated if it was not really allocated.
4436  *
4437  * @deprecated Use av_packet_ref or av_packet_make_refcounted
4438  */
4439 attribute_deprecated
4440 int av_dup_packet(AVPacket *pkt);
4441 /**
4442  * Copy packet, including contents
4443  *
4444  * @return 0 on success, negative AVERROR on fail
4445  *
4446  * @deprecated Use av_packet_ref
4447  */
4448 attribute_deprecated
4449 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4450 
4451 /**
4452  * Copy packet side data
4453  *
4454  * @return 0 on success, negative AVERROR on fail
4455  *
4456  * @deprecated Use av_packet_copy_props
4457  */
4458 attribute_deprecated
4459 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4460 
4461 /**
4462  * Free a packet.
4463  *
4464  * @deprecated Use av_packet_unref
4465  *
4466  * @param pkt packet to free
4467  */
4468 attribute_deprecated
4469 void av_free_packet(AVPacket *pkt);
4470 #endif
4471 /**
4472  * Allocate new information of a packet.
4473  *
4474  * @param pkt packet
4475  * @param type side information type
4476  * @param size side information size
4477  * @return pointer to fresh allocated data or NULL otherwise
4478  */
4479 uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
4480  int size);
4481 
4482 /**
4483  * Wrap an existing array as a packet side data.
4484  *
4485  * @param pkt packet
4486  * @param type side information type
4487  * @param data the side data array. It must be allocated with the av_malloc()
4488  * family of functions. The ownership of the data is transferred to
4489  * pkt.
4490  * @param size side information size
4491  * @return a non-negative number on success, a negative AVERROR code on
4492  * failure. On failure, the packet is unchanged and the data remains
4493  * owned by the caller.
4494  */
4495 int av_packet_add_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
4496  uint8_t *data, size_t size);
4497 
4498 /**
4499  * Shrink the already allocated side data buffer
4500  *
4501  * @param pkt packet
4502  * @param type side information type
4503  * @param size new side information size
4504  * @return 0 on success, < 0 on failure
4505  */
4506 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
4507  int size);
4508 
4509 /**
4510  * Get side information from packet.
4511  *
4512  * @param pkt packet
4513  * @param type desired side information type
4514  * @param size pointer for side information size to store (optional)
4515  * @return pointer to data if present or NULL otherwise
4516  */
4517 uint8_t* av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type,
4518  int *size);
4519 
4520 #if FF_API_MERGE_SD_API
4521 attribute_deprecated
4522 int av_packet_merge_side_data(AVPacket *pkt);
4523 
4524 attribute_deprecated
4525 int av_packet_split_side_data(AVPacket *pkt);
4526 #endif
4527 
4528 const char *av_packet_side_data_name(enum AVPacketSideDataType type);
4529 
4530 /**
4531  * Pack a dictionary for use in side_data.
4532  *
4533  * @param dict The dictionary to pack.
4534  * @param size pointer to store the size of the returned data
4535  * @return pointer to data if successful, NULL otherwise
4536  */
4537 uint8_t *av_packet_pack_dictionary(AVDictionary *dict, int *size);
4538 /**
4539  * Unpack a dictionary from side_data.
4540  *
4541  * @param data data from side_data
4542  * @param size size of the data
4543  * @param dict the metadata storage dictionary
4544  * @return 0 on success, < 0 on failure
4545  */
4546 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4547 
4548 
4549 /**
4550  * Convenience function to free all the side data stored.
4551  * All the other fields stay untouched.
4552  *
4553  * @param pkt packet
4554  */
4555 void av_packet_free_side_data(AVPacket *pkt);
4556 
4557 /**
4558  * Setup a new reference to the data described by a given packet
4559  *
4560  * If src is reference-counted, setup dst as a new reference to the
4561  * buffer in src. Otherwise allocate a new buffer in dst and copy the
4562  * data from src into it.
4563  *
4564  * All the other fields are copied from src.
4565  *
4566  * @see av_packet_unref
4567  *
4568  * @param dst Destination packet
4569  * @param src Source packet
4570  *
4571  * @return 0 on success, a negative AVERROR on error.
4572  */
4573 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4574 
4575 /**
4576  * Wipe the packet.
4577  *
4578  * Unreference the buffer referenced by the packet and reset the
4579  * remaining packet fields to their default values.
4580  *
4581  * @param pkt The packet to be unreferenced.
4582  */
4583 void av_packet_unref(AVPacket *pkt);
4584 
4585 /**
4586  * Move every field in src to dst and reset src.
4587  *
4588  * @see av_packet_unref
4589  *
4590  * @param src Source packet, will be reset
4591  * @param dst Destination packet
4592  */
4593 void av_packet_move_ref(AVPacket *dst, AVPacket *src);
4594 
4595 /**
4596  * Copy only "properties" fields from src to dst.
4597  *
4598  * Properties for the purpose of this function are all the fields
4599  * beside those related to the packet data (buf, data, size)
4600  *
4601  * @param dst Destination packet
4602  * @param src Source packet
4603  *
4604  * @return 0 on success AVERROR on failure.
4605  */
4606 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4607 
4608 /**
4609  * Ensure the data described by a given packet is reference counted.
4610  *
4611  * @note This function does not ensure that the reference will be writable.
4612  * Use av_packet_make_writable instead for that purpose.
4613  *
4614  * @see av_packet_ref
4615  * @see av_packet_make_writable
4616  *
4617  * @param pkt packet whose data should be made reference counted.
4618  *
4619  * @return 0 on success, a negative AVERROR on error. On failure, the
4620  * packet is unchanged.
4621  */
4622 int av_packet_make_refcounted(AVPacket *pkt);
4623 
4624 /**
4625  * Create a writable reference for the data described by a given packet,
4626  * avoiding data copy if possible.
4627  *
4628  * @param pkt Packet whose data should be made writable.
4629  *
4630  * @return 0 on success, a negative AVERROR on failure. On failure, the
4631  * packet is unchanged.
4632  */
4633 int av_packet_make_writable(AVPacket *pkt);
4634 
4635 /**
4636  * Convert valid timing fields (timestamps / durations) in a packet from one
4637  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4638  * ignored.
4639  *
4640  * @param pkt packet on which the conversion will be performed
4641  * @param tb_src source timebase, in which the timing fields in pkt are
4642  * expressed
4643  * @param tb_dst destination timebase, to which the timing fields will be
4644  * converted
4645  */
4646 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4647 
4648 /**
4649  * @}
4650  */
4651 
4652 /**
4653  * @addtogroup lavc_decoding
4654  * @{
4655  */
4656 
4657 /**
4658  * Find a registered decoder with a matching codec ID.
4659  *
4660  * @param id AVCodecID of the requested decoder
4661  * @return A decoder if one was found, NULL otherwise.
4662  */
4663 AVCodec *avcodec_find_decoder(enum AVCodecID id);
4664 
4665 /**
4666  * Find a registered decoder with the specified name.
4667  *
4668  * @param name name of the requested decoder
4669  * @return A decoder if one was found, NULL otherwise.
4670  */
4671 AVCodec *avcodec_find_decoder_by_name(const char *name);
4672 
4673 /**
4674  * The default callback for AVCodecContext.get_buffer2(). It is made public so
4675  * it can be called by custom get_buffer2() implementations for decoders without
4676  * AV_CODEC_CAP_DR1 set.
4677  */
4678 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
4679 
4680 /**
4681  * Modify width and height values so that they will result in a memory
4682  * buffer that is acceptable for the codec if you do not use any horizontal
4683  * padding.
4684  *
4685  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4686  */
4687 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
4688 
4689 /**
4690  * Modify width and height values so that they will result in a memory
4691  * buffer that is acceptable for the codec if you also ensure that all
4692  * line sizes are a multiple of the respective linesize_align[i].
4693  *
4694  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4695  */
4696 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
4697  int linesize_align[AV_NUM_DATA_POINTERS]);
4698 
4699 /**
4700  * Converts AVChromaLocation to swscale x/y chroma position.
4701  *
4702  * The positions represent the chroma (0,0) position in a coordinates system
4703  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4704  *
4705  * @param xpos horizontal chroma sample position
4706  * @param ypos vertical chroma sample position
4707  */
4708 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4709 
4710 /**
4711  * Converts swscale x/y chroma position to AVChromaLocation.
4712  *
4713  * The positions represent the chroma (0,0) position in a coordinates system
4714  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4715  *
4716  * @param xpos horizontal chroma sample position
4717  * @param ypos vertical chroma sample position
4718  */
4719 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4720 
4721 /**
4722  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4723  *
4724  * Some decoders may support multiple frames in a single AVPacket. Such
4725  * decoders would then just decode the first frame and the return value would be
4726  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4727  * called again with an AVPacket containing the remaining data in order to
4728  * decode the second frame, etc... Even if no frames are returned, the packet
4729  * needs to be fed to the decoder with remaining data until it is completely
4730  * consumed or an error occurs.
4731  *
4732  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4733  * and output. This means that for some packets they will not immediately
4734  * produce decoded output and need to be flushed at the end of decoding to get
4735  * all the decoded data. Flushing is done by calling this function with packets
4736  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4737  * returning samples. It is safe to flush even those decoders that are not
4738  * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4739  *
4740  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4741  * larger than the actual read bytes because some optimized bitstream
4742  * readers read 32 or 64 bits at once and could read over the end.
4743  *
4744  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4745  * before packets may be fed to the decoder.
4746  *
4747  * @param avctx the codec context
4748  * @param[out] frame The AVFrame in which to store decoded audio samples.
4749  * The decoder will allocate a buffer for the decoded frame by
4750  * calling the AVCodecContext.get_buffer2() callback.
4751  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4752  * reference counted and the returned reference belongs to the
4753  * caller. The caller must release the frame using av_frame_unref()
4754  * when the frame is no longer needed. The caller may safely write
4755  * to the frame if av_frame_is_writable() returns 1.
4756  * When AVCodecContext.refcounted_frames is set to 0, the returned
4757  * reference belongs to the decoder and is valid only until the
4758  * next call to this function or until closing or flushing the
4759  * decoder. The caller may not write to it.
4760  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4761  * non-zero. Note that this field being set to zero
4762  * does not mean that an error has occurred. For
4763  * decoders with AV_CODEC_CAP_DELAY set, no given decode
4764  * call is guaranteed to produce a frame.
4765  * @param[in] avpkt The input AVPacket containing the input buffer.
4766  * At least avpkt->data and avpkt->size should be set. Some
4767  * decoders might also require additional fields to be set.
4768  * @return A negative error code is returned if an error occurred during
4769  * decoding, otherwise the number of bytes consumed from the input
4770  * AVPacket is returned.
4771  *
4772 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4773  */
4774 attribute_deprecated
4775 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
4776  int *got_frame_ptr, const AVPacket *avpkt);
4777 
4778 /**
4779  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4780  * Some decoders may support multiple frames in a single AVPacket, such
4781  * decoders would then just decode the first frame.
4782  *
4783  * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4784  * the actual read bytes because some optimized bitstream readers read 32 or 64
4785  * bits at once and could read over the end.
4786  *
4787  * @warning The end of the input buffer buf should be set to 0 to ensure that
4788  * no overreading happens for damaged MPEG streams.
4789  *
4790  * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4791  * between input and output, these need to be fed with avpkt->data=NULL,
4792  * avpkt->size=0 at the end to return the remaining frames.
4793  *
4794  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4795  * before packets may be fed to the decoder.
4796  *
4797  * @param avctx the codec context
4798  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4799  * Use av_frame_alloc() to get an AVFrame. The codec will
4800  * allocate memory for the actual bitmap by calling the
4801  * AVCodecContext.get_buffer2() callback.
4802  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4803  * reference counted and the returned reference belongs to the
4804  * caller. The caller must release the frame using av_frame_unref()
4805  * when the frame is no longer needed. The caller may safely write
4806  * to the frame if av_frame_is_writable() returns 1.
4807  * When AVCodecContext.refcounted_frames is set to 0, the returned
4808  * reference belongs to the decoder and is valid only until the
4809  * next call to this function or until closing or flushing the
4810  * decoder. The caller may not write to it.
4811  *
4812  * @param[in] avpkt The input AVPacket containing the input buffer.
4813  * You can create such packet with av_init_packet() and by then setting
4814  * data and size, some decoders might in addition need other fields like
4815  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4816  * fields possible.
4817  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4818  * @return On error a negative value is returned, otherwise the number of bytes
4819  * used or zero if no frame could be decompressed.
4820  *
4821  * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4822  */
4823 attribute_deprecated
4824 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4825  int *got_picture_ptr,
4826  const AVPacket *avpkt);
4827 
4828 /**
4829  * Decode a subtitle message.
4830  * Return a negative value on error, otherwise return the number of bytes used.
4831  * If no subtitle could be decompressed, got_sub_ptr is zero.
4832  * Otherwise, the subtitle is stored in *sub.
4833  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4834  * simplicity, because the performance difference is expect to be negligible
4835  * and reusing a get_buffer written for video codecs would probably perform badly
4836  * due to a potentially very different allocation pattern.
4837  *
4838  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4839  * and output. This means that for some packets they will not immediately
4840  * produce decoded output and need to be flushed at the end of decoding to get
4841  * all the decoded data. Flushing is done by calling this function with packets
4842  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4843  * returning subtitles. It is safe to flush even those decoders that are not
4844  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
4845  *
4846  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4847  * before packets may be fed to the decoder.
4848  *
4849  * @param avctx the codec context
4850  * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4851  * must be freed with avsubtitle_free if *got_sub_ptr is set.
4852  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4853  * @param[in] avpkt The input AVPacket containing the input buffer.
4854  */
4855 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
4856  int *got_sub_ptr,
4857  AVPacket *avpkt);
4858 
4859 /**
4860  * Supply raw packet data as input to a decoder.
4861  *
4862  * Internally, this call will copy relevant AVCodecContext fields, which can
4863  * influence decoding per-packet, and apply them when the packet is actually
4864  * decoded. (For example AVCodecContext.skip_frame, which might direct the
4865  * decoder to drop the frame contained by the packet sent with this function.)
4866  *
4867  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4868  * larger than the actual read bytes because some optimized bitstream
4869  * readers read 32 or 64 bits at once and could read over the end.
4870  *
4871  * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4872  * on the same AVCodecContext. It will return unexpected results now
4873  * or in future libavcodec versions.
4874  *
4875  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4876  * before packets may be fed to the decoder.
4877  *
4878  * @param avctx codec context
4879  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4880  * frame, or several complete audio frames.
4881  * Ownership of the packet remains with the caller, and the
4882  * decoder will not write to the packet. The decoder may create
4883  * a reference to the packet data (or copy it if the packet is
4884  * not reference-counted).
4885  * Unlike with older APIs, the packet is always fully consumed,
4886  * and if it contains multiple frames (e.g. some audio codecs),
4887  * will require you to call avcodec_receive_frame() multiple
4888  * times afterwards before you can send a new packet.
4889  * It can be NULL (or an AVPacket with data set to NULL and
4890  * size set to 0); in this case, it is considered a flush
4891  * packet, which signals the end of the stream. Sending the
4892  * first flush packet will return success. Subsequent ones are
4893  * unnecessary and will return AVERROR_EOF. If the decoder
4894  * still has frames buffered, it will return them after sending
4895  * a flush packet.
4896  *
4897  * @return 0 on success, otherwise negative error code:
4898  * AVERROR(EAGAIN): input is not accepted in the current state - user
4899  * must read output with avcodec_receive_frame() (once
4900  * all output is read, the packet should be resent, and
4901  * the call will not fail with EAGAIN).
4902  * AVERROR_EOF: the decoder has been flushed, and no new packets can
4903  * be sent to it (also returned if more than 1 flush
4904  * packet is sent)
4905  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4906  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4907  * other errors: legitimate decoding errors
4908  */
4909 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4910 
4911 /**
4912  * Return decoded output data from a decoder.
4913  *
4914  * @param avctx codec context
4915  * @param frame This will be set to a reference-counted video or audio
4916  * frame (depending on the decoder type) allocated by the
4917  * decoder. Note that the function will always call
4918  * av_frame_unref(frame) before doing anything else.
4919  *
4920  * @return
4921  * 0: success, a frame was returned
4922  * AVERROR(EAGAIN): output is not available in this state - user must try
4923  * to send new input
4924  * AVERROR_EOF: the decoder has been fully flushed, and there will be
4925  * no more output frames
4926  * AVERROR(EINVAL): codec not opened, or it is an encoder
4927  * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
4928  * with respect to first decoded frame. Applicable
4929  * when flag AV_CODEC_FLAG_DROPCHANGED is set.
4930  * other negative values: legitimate decoding errors
4931  */
4932 int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
4933 
4934 /**
4935  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
4936  * to retrieve buffered output packets.
4937  *
4938  * @param avctx codec context
4939  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
4940  * Ownership of the frame remains with the caller, and the
4941  * encoder will not write to the frame. The encoder may create
4942  * a reference to the frame data (or copy it if the frame is
4943  * not reference-counted).
4944  * It can be NULL, in which case it is considered a flush
4945  * packet. This signals the end of the stream. If the encoder
4946  * still has packets buffered, it will return them after this
4947  * call. Once flushing mode has been entered, additional flush
4948  * packets are ignored, and sending frames will return
4949  * AVERROR_EOF.
4950  *
4951  * For audio:
4952  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4953  * can have any number of samples.
4954  * If it is not set, frame->nb_samples must be equal to
4955  * avctx->frame_size for all frames except the last.
4956  * The final frame may be smaller than avctx->frame_size.
4957  * @return 0 on success, otherwise negative error code:
4958  * AVERROR(EAGAIN): input is not accepted in the current state - user
4959  * must read output with avcodec_receive_packet() (once
4960  * all output is read, the packet should be resent, and
4961  * the call will not fail with EAGAIN).
4962  * AVERROR_EOF: the encoder has been flushed, and no new frames can
4963  * be sent to it
4964  * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
4965  * decoder, or requires flush
4966  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4967  * other errors: legitimate decoding errors
4968  */
4969 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
4970 
4971 /**
4972  * Read encoded data from the encoder.
4973  *
4974  * @param avctx codec context
4975  * @param avpkt This will be set to a reference-counted packet allocated by the
4976  * encoder. Note that the function will always call
4977  * av_frame_unref(frame) before doing anything else.
4978  * @return 0 on success, otherwise negative error code:
4979  * AVERROR(EAGAIN): output is not available in the current state - user
4980  * must try to send input
4981  * AVERROR_EOF: the encoder has been fully flushed, and there will be
4982  * no more output packets
4983  * AVERROR(EINVAL): codec not opened, or it is an encoder
4984  * other errors: legitimate decoding errors
4985  */
4986 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
4987 
4988 /**
4989  * Create and return a AVHWFramesContext with values adequate for hardware
4990  * decoding. This is meant to get called from the get_format callback, and is
4991  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
4992  * This API is for decoding with certain hardware acceleration modes/APIs only.
4993  *
4994  * The returned AVHWFramesContext is not initialized. The caller must do this
4995  * with av_hwframe_ctx_init().
4996  *
4997  * Calling this function is not a requirement, but makes it simpler to avoid
4998  * codec or hardware API specific details when manually allocating frames.
4999  *
5000  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
5001  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
5002  * it unnecessary to call this function or having to care about
5003  * AVHWFramesContext initialization at all.
5004  *
5005  * There are a number of requirements for calling this function:
5006  *
5007  * - It must be called from get_format with the same avctx parameter that was
5008  * passed to get_format. Calling it outside of get_format is not allowed, and
5009  * can trigger undefined behavior.
5010  * - The function is not always supported (see description of return values).
5011  * Even if this function returns successfully, hwaccel initialization could
5012  * fail later. (The degree to which implementations check whether the stream
5013  * is actually supported varies. Some do this check only after the user's
5014  * get_format callback returns.)
5015  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
5016  * user decides to use a AVHWFramesContext prepared with this API function,
5017  * the user must return the same hw_pix_fmt from get_format.
5018  * - The device_ref passed to this function must support the given hw_pix_fmt.
5019  * - After calling this API function, it is the user's responsibility to
5020  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
5021  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
5022  * before returning from get_format (this is implied by the normal
5023  * AVCodecContext.hw_frames_ctx API rules).
5024  * - The AVHWFramesContext parameters may change every time time get_format is
5025  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
5026  * you are inherently required to go through this process again on every
5027  * get_format call.
5028  * - It is perfectly possible to call this function without actually using
5029  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
5030  * previously initialized AVHWFramesContext, and calling this API function
5031  * only to test whether the required frame parameters have changed.
5032  * - Fields that use dynamically allocated values of any kind must not be set
5033  * by the user unless setting them is explicitly allowed by the documentation.
5034  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
5035  * the new free callback must call the potentially set previous free callback.
5036  * This API call may set any dynamically allocated fields, including the free
5037  * callback.
5038  *
5039  * The function will set at least the following fields on AVHWFramesContext
5040  * (potentially more, depending on hwaccel API):
5041  *
5042  * - All fields set by av_hwframe_ctx_alloc().
5043  * - Set the format field to hw_pix_fmt.
5044  * - Set the sw_format field to the most suited and most versatile format. (An
5045  * implication is that this will prefer generic formats over opaque formats
5046  * with arbitrary restrictions, if possible.)
5047  * - Set the width/height fields to the coded frame size, rounded up to the
5048  * API-specific minimum alignment.
5049  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
5050  * field to the number of maximum reference surfaces possible with the codec,
5051  * plus 1 surface for the user to work (meaning the user can safely reference
5052  * at most 1 decoded surface at a time), plus additional buffering introduced
5053  * by frame threading. If the hwaccel does not require pre-allocation, the
5054  * field is left to 0, and the decoder will allocate new surfaces on demand
5055  * during decoding.
5056  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
5057  * hardware API.
5058  *
5059  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
5060  * with basic frame parameters set.
5061  *
5062  * The function is stateless, and does not change the AVCodecContext or the
5063  * device_ref AVHWDeviceContext.
5064  *
5065  * @param avctx The context which is currently calling get_format, and which
5066  * implicitly contains all state needed for filling the returned
5067  * AVHWFramesContext properly.
5068  * @param device_ref A reference to the AVHWDeviceContext describing the device
5069  * which will be used by the hardware decoder.
5070  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
5071  * @param out_frames_ref On success, set to a reference to an _uninitialized_
5072  * AVHWFramesContext, created from the given device_ref.
5073  * Fields will be set to values required for decoding.
5074  * Not changed if an error is returned.
5075  * @return zero on success, a negative value on error. The following error codes
5076  * have special semantics:
5077  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
5078  * is always manual, or it is a decoder which does not
5079  * support setting AVCodecContext.hw_frames_ctx at all,
5080  * or it is a software format.
5081  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
5082  * this configuration, or the device_ref is not supported
5083  * for the hwaccel referenced by hw_pix_fmt.
5084  */
5085 int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
5086  AVBufferRef *device_ref,
5087  enum AVPixelFormat hw_pix_fmt,
5088  AVBufferRef **out_frames_ref);
5089 
5090 
5091 
5092 /**
5093  * @defgroup lavc_parsing Frame parsing
5094  * @{
5095  */
5096 
5097 enum AVPictureStructure {
5098  AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
5099  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
5100  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
5101  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
5102 };
5103 
5104 typedef struct AVCodecParserContext {
5105  void *priv_data;
5106  struct AVCodecParser *parser;
5107  int64_t frame_offset; /* offset of the current frame */
5108  int64_t cur_offset; /* current offset
5109  (incremented by each av_parser_parse()) */
5110  int64_t next_frame_offset; /* offset of the next frame */
5111  /* video info */
5112  int pict_type; /* XXX: Put it back in AVCodecContext. */
5113  /**
5114  * This field is used for proper frame duration computation in lavf.
5115  * It signals, how much longer the frame duration of the current frame
5116  * is compared to normal frame duration.
5117  *
5118  * frame_duration = (1 + repeat_pict) * time_base
5119  *
5120  * It is used by codecs like H.264 to display telecined material.
5121  */
5122  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
5123  int64_t pts; /* pts of the current frame */
5124  int64_t dts; /* dts of the current frame */
5125 
5126  /* private data */
5127  int64_t last_pts;
5128  int64_t last_dts;
5129  int fetch_timestamp;
5130 
5131 #define AV_PARSER_PTS_NB 4
5132  int cur_frame_start_index;
5133  int64_t cur_frame_offset[AV_PARSER_PTS_NB];
5134  int64_t cur_frame_pts[AV_PARSER_PTS_NB];
5135  int64_t cur_frame_dts[AV_PARSER_PTS_NB];
5136 
5137  int flags;
5138 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
5139 #define PARSER_FLAG_ONCE 0x0002
5140 /// Set if the parser has a valid file offset
5141 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
5142 #define PARSER_FLAG_USE_CODEC_TS 0x1000
5143 
5144  int64_t offset; ///< byte offset from starting packet start
5145  int64_t cur_frame_end[AV_PARSER_PTS_NB];
5146 
5147  /**
5148  * Set by parser to 1 for key frames and 0 for non-key frames.
5149  * It is initialized to -1, so if the parser doesn't set this flag,
5150  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
5151  * will be used.
5152  */
5153  int key_frame;
5154 
5155 #if FF_API_CONVERGENCE_DURATION
5156  /**
5157  * @deprecated unused
5158  */
5159  attribute_deprecated
5160  int64_t convergence_duration;
5161 #endif
5162 
5163  // Timestamp generation support:
5164  /**
5165  * Synchronization point for start of timestamp generation.
5166  *
5167  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
5168  * (default).
5169  *
5170  * For example, this corresponds to presence of H.264 buffering period
5171  * SEI message.
5172  */
5173  int dts_sync_point;
5174 
5175  /**
5176  * Offset of the current timestamp against last timestamp sync point in
5177  * units of AVCodecContext.time_base.
5178  *
5179  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5180  * contain a valid timestamp offset.
5181  *
5182  * Note that the timestamp of sync point has usually a nonzero
5183  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
5184  * the next frame after timestamp sync point will be usually 1.
5185  *
5186  * For example, this corresponds to H.264 cpb_removal_delay.
5187  */
5188  int dts_ref_dts_delta;
5189 
5190  /**
5191  * Presentation delay of current frame in units of AVCodecContext.time_base.
5192  *
5193  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5194  * contain valid non-negative timestamp delta (presentation time of a frame
5195  * must not lie in the past).
5196  *
5197  * This delay represents the difference between decoding and presentation
5198  * time of the frame.
5199  *
5200  * For example, this corresponds to H.264 dpb_output_delay.
5201  */
5202  int pts_dts_delta;
5203 
5204  /**
5205  * Position of the packet in file.
5206  *
5207  * Analogous to cur_frame_pts/dts
5208  */
5209  int64_t cur_frame_pos[AV_PARSER_PTS_NB];
5210 
5211  /**
5212  * Byte position of currently parsed frame in stream.
5213  */
5214  int64_t pos;
5215 
5216  /**
5217  * Previous frame byte position.
5218  */
5219  int64_t last_pos;
5220 
5221  /**
5222  * Duration of the current frame.
5223  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5224  * For all other types, this is in units of AVCodecContext.time_base.
5225  */
5226  int duration;
5227 
5228  enum AVFieldOrder field_order;
5229 
5230  /**
5231  * Indicate whether a picture is coded as a frame, top field or bottom field.
5232  *
5233  * For example, H.264 field_pic_flag equal to 0 corresponds to
5234  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5235  * equal to 1 and bottom_field_flag equal to 0 corresponds to
5236  * AV_PICTURE_STRUCTURE_TOP_FIELD.
5237  */
5238  enum AVPictureStructure picture_structure;
5239 
5240  /**
5241  * Picture number incremented in presentation or output order.
5242  * This field may be reinitialized at the first picture of a new sequence.
5243  *
5244  * For example, this corresponds to H.264 PicOrderCnt.
5245  */
5246  int output_picture_number;
5247 
5248  /**
5249  * Dimensions of the decoded video intended for presentation.
5250  */
5251  int width;
5252  int height;
5253 
5254  /**
5255  * Dimensions of the coded video.
5256  */
5257  int coded_width;
5258  int coded_height;
5259 
5260  /**
5261  * The format of the coded data, corresponds to enum AVPixelFormat for video
5262  * and for enum AVSampleFormat for audio.
5263  *
5264  * Note that a decoder can have considerable freedom in how exactly it
5265  * decodes the data, so the format reported here might be different from the
5266  * one returned by a decoder.
5267  */
5268  int format;
5269 } AVCodecParserContext;
5270 
5271 typedef struct AVCodecParser {
5272  int codec_ids[5]; /* several codec IDs are permitted */
5273  int priv_data_size;
5274  int (*parser_init)(AVCodecParserContext *s);
5275  /* This callback never returns an error, a negative value means that
5276  * the frame start was in a previous packet. */
5277  int (*parser_parse)(AVCodecParserContext *s,
5278  AVCodecContext *avctx,
5279  const uint8_t **poutbuf, int *poutbuf_size,
5280  const uint8_t *buf, int buf_size);
5281  void (*parser_close)(AVCodecParserContext *s);
5282  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5283  struct AVCodecParser *next;
5284 } AVCodecParser;
5285 
5286 /**
5287  * Iterate over all registered codec parsers.
5288  *
5289  * @param opaque a pointer where libavcodec will store the iteration state. Must
5290  * point to NULL to start the iteration.
5291  *
5292  * @return the next registered codec parser or NULL when the iteration is
5293  * finished
5294  */
5295 const AVCodecParser *av_parser_iterate(void **opaque);
5296 
5297 attribute_deprecated
5298 AVCodecParser *av_parser_next(const AVCodecParser *c);
5299 
5300 attribute_deprecated
5301 void av_register_codec_parser(AVCodecParser *parser);
5302 AVCodecParserContext *av_parser_init(int codec_id);
5303 
5304 /**
5305  * Parse a packet.
5306  *
5307  * @param s parser context.
5308  * @param avctx codec context.
5309  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5310  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5311  * @param buf input buffer.
5312  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
5313  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
5314  To signal EOF, this should be 0 (so that the last frame
5315  can be output).
5316  * @param pts input presentation timestamp.
5317  * @param dts input decoding timestamp.
5318  * @param pos input byte position in stream.
5319  * @return the number of bytes of the input bitstream used.
5320  *
5321  * Example:
5322  * @code
5323  * while(in_len){
5324  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5325  * in_data, in_len,
5326  * pts, dts, pos);
5327  * in_data += len;
5328  * in_len -= len;
5329  *
5330  * if(size)
5331  * decode_frame(data, size);
5332  * }
5333  * @endcode
5334  */
5335 int av_parser_parse2(AVCodecParserContext *s,
5336  AVCodecContext *avctx,
5337  uint8_t **poutbuf, int *poutbuf_size,
5338  const uint8_t *buf, int buf_size,
5339  int64_t pts, int64_t dts,
5340  int64_t pos);
5341 
5342 /**
5343  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
5344  * @deprecated use AVBitStreamFilter
5345  */
5346 int av_parser_change(AVCodecParserContext *s,
5347  AVCodecContext *avctx,
5348  uint8_t **poutbuf, int *poutbuf_size,
5349  const uint8_t *buf, int buf_size, int keyframe);
5350 void av_parser_close(AVCodecParserContext *s);
5351 
5352 /**
5353  * @}
5354  * @}
5355  */
5356 
5357 /**
5358  * @addtogroup lavc_encoding
5359  * @{
5360  */
5361 
5362 /**
5363  * Find a registered encoder with a matching codec ID.
5364  *
5365  * @param id AVCodecID of the requested encoder
5366  * @return An encoder if one was found, NULL otherwise.
5367  */
5368 AVCodec *avcodec_find_encoder(enum AVCodecID id);
5369 
5370 /**
5371  * Find a registered encoder with the specified name.
5372  *
5373  * @param name name of the requested encoder
5374  * @return An encoder if one was found, NULL otherwise.
5375  */
5376 AVCodec *avcodec_find_encoder_by_name(const char *name);
5377 
5378 /**
5379  * Encode a frame of audio.
5380  *
5381  * Takes input samples from frame and writes the next output packet, if
5382  * available, to avpkt. The output packet does not necessarily contain data for
5383  * the most recent frame, as encoders can delay, split, and combine input frames
5384  * internally as needed.
5385  *
5386  * @param avctx codec context
5387  * @param avpkt output AVPacket.
5388  * The user can supply an output buffer by setting
5389  * avpkt->data and avpkt->size prior to calling the
5390  * function, but if the size of the user-provided data is not
5391  * large enough, encoding will fail. If avpkt->data and
5392  * avpkt->size are set, avpkt->destruct must also be set. All
5393  * other AVPacket fields will be reset by the encoder using
5394  * av_init_packet(). If avpkt->data is NULL, the encoder will
5395  * allocate it. The encoder will set avpkt->size to the size
5396  * of the output packet.
5397  *
5398  * If this function fails or produces no output, avpkt will be
5399  * freed using av_packet_unref().
5400  * @param[in] frame AVFrame containing the raw audio data to be encoded.
5401  * May be NULL when flushing an encoder that has the
5402  * AV_CODEC_CAP_DELAY capability set.
5403  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5404  * can have any number of samples.
5405  * If it is not set, frame->nb_samples must be equal to
5406  * avctx->frame_size for all frames except the last.
5407  * The final frame may be smaller than avctx->frame_size.
5408  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5409  * output packet is non-empty, and to 0 if it is
5410  * empty. If the function returns an error, the
5411  * packet can be assumed to be invalid, and the
5412  * value of got_packet_ptr is undefined and should
5413  * not be used.
5414  * @return 0 on success, negative error code on failure
5415  *
5416  * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5417  */
5418 attribute_deprecated
5419 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
5420  const AVFrame *frame, int *got_packet_ptr);
5421 
5422 /**
5423  * Encode a frame of video.
5424  *
5425  * Takes input raw video data from frame and writes the next output packet, if
5426  * available, to avpkt. The output packet does not necessarily contain data for
5427  * the most recent frame, as encoders can delay and reorder input frames
5428  * internally as needed.
5429  *
5430  * @param avctx codec context
5431  * @param avpkt output AVPacket.
5432  * The user can supply an output buffer by setting
5433  * avpkt->data and avpkt->size prior to calling the
5434  * function, but if the size of the user-provided data is not
5435  * large enough, encoding will fail. All other AVPacket fields
5436  * will be reset by the encoder using av_init_packet(). If
5437  * avpkt->data is NULL, the encoder will allocate it.
5438  * The encoder will set avpkt->size to the size of the
5439  * output packet. The returned data (if any) belongs to the
5440  * caller, he is responsible for freeing it.
5441  *
5442  * If this function fails or produces no output, avpkt will be
5443  * freed using av_packet_unref().
5444  * @param[in] frame AVFrame containing the raw video data to be encoded.
5445  * May be NULL when flushing an encoder that has the