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 "libavutil/samplefmt.h"
31 #include "libavutil/attributes.h"
32 #include "libavutil/avutil.h"
33 #include "libavutil/buffer.h"
34 #include "libavutil/dict.h"
35 #include "libavutil/frame.h"
36 #include "libavutil/log.h"
37 #include "libavutil/pixfmt.h"
38 #include "libavutil/rational.h"
39 
40 #include "codec.h"
41 #include "codec_desc.h"
42 #include "codec_par.h"
43 #include "codec_id.h"
44 #include "defs.h"
45 #include "packet.h"
46 #include "version.h"
47 
48 /**
49  * @defgroup libavc libavcodec
50  * Encoding/Decoding Library
51  *
52  * @{
53  *
54  * @defgroup lavc_decoding Decoding
55  * @{
56  * @}
57  *
58  * @defgroup lavc_encoding Encoding
59  * @{
60  * @}
61  *
62  * @defgroup lavc_codec Codecs
63  * @{
64  * @defgroup lavc_codec_native Native Codecs
65  * @{
66  * @}
67  * @defgroup lavc_codec_wrappers External library wrappers
68  * @{
69  * @}
70  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
71  * @{
72  * @}
73  * @}
74  * @defgroup lavc_internal Internal
75  * @{
76  * @}
77  * @}
78  */
79 
80 /**
81  * @ingroup libavc
82  * @defgroup lavc_encdec send/receive encoding and decoding API overview
83  * @{
84  *
85  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
86  * avcodec_receive_packet() functions provide an encode/decode API, which
87  * decouples input and output.
88  *
89  * The API is very similar for encoding/decoding and audio/video, and works as
90  * follows:
91  * - Set up and open the AVCodecContext as usual.
92  * - Send valid input:
93  * - For decoding, call avcodec_send_packet() to give the decoder raw
94  * compressed data in an AVPacket.
95  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
96  * containing uncompressed audio or video.
97  *
98  * In both cases, it is recommended that AVPackets and AVFrames are
99  * refcounted, or libavcodec might have to copy the input data. (libavformat
100  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
101  * refcounted AVFrames.)
102  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
103  * functions and process their output:
104  * - For decoding, call avcodec_receive_frame(). On success, it will return
105  * an AVFrame containing uncompressed audio or video data.
106  * - For encoding, call avcodec_receive_packet(). On success, it will return
107  * an AVPacket with a compressed frame.
108  *
109  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
110  * AVERROR(EAGAIN) return value means that new input data is required to
111  * return new output. In this case, continue with sending input. For each
112  * input frame/packet, the codec will typically return 1 output frame/packet,
113  * but it can also be 0 or more than 1.
114  *
115  * At the beginning of decoding or encoding, the codec might accept multiple
116  * input frames/packets without returning a frame, until its internal buffers
117  * are filled. This situation is handled transparently if you follow the steps
118  * outlined above.
119  *
120  * In theory, sending input can result in EAGAIN - this should happen only if
121  * not all output was received. You can use this to structure alternative decode
122  * or encode loops other than the one suggested above. For example, you could
123  * try sending new input on each iteration, and try to receive output if that
124  * returns EAGAIN.
125  *
126  * End of stream situations. These require "flushing" (aka draining) the codec,
127  * as the codec might buffer multiple frames or packets internally for
128  * performance or out of necessity (consider B-frames).
129  * This is handled as follows:
130  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
131  * or avcodec_send_frame() (encoding) functions. This will enter draining
132  * mode.
133  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
134  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
135  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
136  * - Before decoding can be resumed again, the codec has to be reset with
137  * avcodec_flush_buffers().
138  *
139  * Using the API as outlined above is highly recommended. But it is also
140  * possible to call functions outside of this rigid schema. For example, you can
141  * call avcodec_send_packet() repeatedly without calling
142  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
143  * until the codec's internal buffer has been filled up (which is typically of
144  * size 1 per output frame, after initial input), and then reject input with
145  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
146  * read at least some output.
147  *
148  * Not all codecs will follow a rigid and predictable dataflow; the only
149  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
150  * one end implies that a receive/send call on the other end will succeed, or
151  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
152  * permit unlimited buffering of input or output.
153  *
154  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
155  * would be an invalid state, which could put the codec user into an endless
156  * loop. The API has no concept of time either: it cannot happen that trying to
157  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
158  * later accepts the packet (with no other receive/flush API calls involved).
159  * The API is a strict state machine, and the passage of time is not supposed
160  * to influence it. Some timing-dependent behavior might still be deemed
161  * acceptable in certain cases. But it must never result in both send/receive
162  * returning EAGAIN at the same time at any point. It must also absolutely be
163  * avoided that the current state is "unstable" and can "flip-flop" between
164  * the send/receive APIs allowing progress. For example, it's not allowed that
165  * the codec randomly decides that it actually wants to consume a packet now
166  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
167  * avcodec_send_packet() call.
168  * @}
169  */
170 
171 /**
172  * @defgroup lavc_core Core functions/structures.
173  * @ingroup libavc
174  *
175  * Basic definitions, functions for querying libavcodec capabilities,
176  * allocating core structures, etc.
177  * @{
178  */
179 
180 /**
181  * @ingroup lavc_encoding
182  * minimum encoding buffer size
183  * Used to avoid some checks during header writing.
184  */
185 #define AV_INPUT_BUFFER_MIN_SIZE 16384
186 
187 /**
188  * @ingroup lavc_encoding
189  */
190 typedef struct RcOverride{
193  int qscale; // If this is 0 then quality_factor will be used instead.
195 } RcOverride;
196 
197 /* encoding support
198  These flags can be passed in AVCodecContext.flags before initialization.
199  Note: Not everything is supported yet.
200 */
201 
202 /**
203  * Allow decoders to produce frames with data planes that are not aligned
204  * to CPU requirements (e.g. due to cropping).
205  */
206 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
207 /**
208  * Use fixed qscale.
209  */
210 #define AV_CODEC_FLAG_QSCALE (1 << 1)
211 /**
212  * 4 MV per MB allowed / advanced prediction for H.263.
213  */
214 #define AV_CODEC_FLAG_4MV (1 << 2)
215 /**
216  * Output even those frames that might be corrupted.
217  */
218 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
219 /**
220  * Use qpel MC.
221  */
222 #define AV_CODEC_FLAG_QPEL (1 << 4)
223 /**
224  * Don't output frames whose parameters differ from first
225  * decoded frame in stream.
226  */
227 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
228 /**
229  * Use internal 2pass ratecontrol in first pass mode.
230  */
231 #define AV_CODEC_FLAG_PASS1 (1 << 9)
232 /**
233  * Use internal 2pass ratecontrol in second pass mode.
234  */
235 #define AV_CODEC_FLAG_PASS2 (1 << 10)
236 /**
237  * loop filter.
238  */
239 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
240 /**
241  * Only decode/encode grayscale.
242  */
243 #define AV_CODEC_FLAG_GRAY (1 << 13)
244 /**
245  * error[?] variables will be set during encoding.
246  */
247 #define AV_CODEC_FLAG_PSNR (1 << 15)
248 #if FF_API_FLAG_TRUNCATED
249 /**
250  * Input bitstream might be truncated at a random location
251  * instead of only at frame boundaries.
252  *
253  * @deprecated use codec parsers for packetizing input
254  */
255 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
256 #endif
257 /**
258  * Use interlaced DCT.
259  */
260 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
261 /**
262  * Force low delay.
263  */
264 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
265 /**
266  * Place global headers in extradata instead of every keyframe.
267  */
268 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
269 /**
270  * Use only bitexact stuff (except (I)DCT).
271  */
272 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
273 /* Fx : Flag for H.263+ extra options */
274 /**
275  * H.263 advanced intra coding / MPEG-4 AC prediction
276  */
277 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
278 /**
279  * interlaced motion estimation
280  */
281 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
282 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
283 
284 /**
285  * Allow non spec compliant speedup tricks.
286  */
287 #define AV_CODEC_FLAG2_FAST (1 << 0)
288 /**
289  * Skip bitstream encoding.
290  */
291 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
292 /**
293  * Place global headers at every keyframe instead of in extradata.
294  */
295 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
296 
297 /**
298  * timecode is in drop frame format. DEPRECATED!!!!
299  */
300 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
301 
302 /**
303  * Input bitstream might be truncated at a packet boundaries
304  * instead of only at frame boundaries.
305  */
306 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
307 /**
308  * Discard cropping information from SPS.
309  */
310 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
311 
312 /**
313  * Show all frames before the first keyframe
314  */
315 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
316 /**
317  * Export motion vectors through frame side data
318  */
319 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
320 /**
321  * Do not skip samples and export skip information as frame side data
322  */
323 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
324 /**
325  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
326  */
327 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
328 
329 /* Unsupported options :
330  * Syntax Arithmetic coding (SAC)
331  * Reference Picture Selection
332  * Independent Segment Decoding */
333 /* /Fx */
334 /* codec capabilities */
335 
336 /* Exported side data.
337  These flags can be passed in AVCodecContext.export_side_data before initialization.
338 */
339 /**
340  * Export motion vectors through frame side data
341  */
342 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
343 /**
344  * Export encoder Producer Reference Time through packet side data
345  */
346 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
347 /**
348  * Decoding only.
349  * Export the AVVideoEncParams structure through frame side data.
350  */
351 #define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
352 /**
353  * Decoding only.
354  * Do not apply film grain, export it instead.
355  */
356 #define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
357 
358 /**
359  * The decoder will keep a reference to the frame and may reuse it later.
360  */
361 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
362 
363 /**
364  * The encoder will keep a reference to the packet and may reuse it later.
365  */
366 #define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
367 
368 struct AVCodecInternal;
369 
370 /**
371  * main external API structure.
372  * New fields can be added to the end with minor version bumps.
373  * Removal, reordering and changes to existing fields require a major
374  * version bump.
375  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
376  * applications.
377  * The name string for AVOptions options matches the associated command line
378  * parameter name and can be found in libavcodec/options_table.h
379  * The AVOption/command line parameter names differ in some cases from the C
380  * structure field names for historic reasons or brevity.
381  * sizeof(AVCodecContext) must not be used outside libav*.
382  */
383 typedef struct AVCodecContext {
384  /**
385  * information on struct for av_log
386  * - set by avcodec_alloc_context3
387  */
390 
391  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
392  const struct AVCodec *codec;
393  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
394 
395  /**
396  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
397  * This is used to work around some encoder bugs.
398  * A demuxer should set this to what is stored in the field used to identify the codec.
399  * If there are multiple such fields in a container then the demuxer should choose the one
400  * which maximizes the information about the used codec.
401  * If the codec tag field in a container is larger than 32 bits then the demuxer should
402  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
403  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
404  * first.
405  * - encoding: Set by user, if not then the default based on codec_id will be used.
406  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
407  */
408  unsigned int codec_tag;
409 
410  void *priv_data;
411 
412  /**
413  * Private context used for internal data.
414  *
415  * Unlike priv_data, this is not codec-specific. It is used in general
416  * libavcodec functions.
417  */
418  struct AVCodecInternal *internal;
419 
420  /**
421  * Private data of the user, can be used to carry app specific stuff.
422  * - encoding: Set by user.
423  * - decoding: Set by user.
424  */
425  void *opaque;
426 
427  /**
428  * the average bitrate
429  * - encoding: Set by user; unused for constant quantizer encoding.
430  * - decoding: Set by user, may be overwritten by libavcodec
431  * if this info is available in the stream
432  */
433  int64_t bit_rate;
434 
435  /**
436  * number of bits the bitstream is allowed to diverge from the reference.
437  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
438  * - encoding: Set by user; unused for constant quantizer encoding.
439  * - decoding: unused
440  */
442 
443  /**
444  * Global quality for codecs which cannot change it per frame.
445  * This should be proportional to MPEG-1/2/4 qscale.
446  * - encoding: Set by user.
447  * - decoding: unused
448  */
450 
451  /**
452  * - encoding: Set by user.
453  * - decoding: unused
454  */
456 #define FF_COMPRESSION_DEFAULT -1
457 
458  /**
459  * AV_CODEC_FLAG_*.
460  * - encoding: Set by user.
461  * - decoding: Set by user.
462  */
463  int flags;
464 
465  /**
466  * AV_CODEC_FLAG2_*
467  * - encoding: Set by user.
468  * - decoding: Set by user.
469  */
470  int flags2;
471 
472  /**
473  * some codecs need / can use extradata like Huffman tables.
474  * MJPEG: Huffman tables
475  * rv10: additional flags
476  * MPEG-4: global headers (they can be in the bitstream or here)
477  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
478  * than extradata_size to avoid problems if it is read with the bitstream reader.
479  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
480  * Must be allocated with the av_malloc() family of functions.
481  * - encoding: Set/allocated/freed by libavcodec.
482  * - decoding: Set/allocated/freed by user.
483  */
484  uint8_t *extradata;
486 
487  /**
488  * This is the fundamental unit of time (in seconds) in terms
489  * of which frame timestamps are represented. For fixed-fps content,
490  * timebase should be 1/framerate and timestamp increments should be
491  * identically 1.
492  * This often, but not always is the inverse of the frame rate or field rate
493  * for video. 1/time_base is not the average frame rate if the frame rate is not
494  * constant.
495  *
496  * Like containers, elementary streams also can store timestamps, 1/time_base
497  * is the unit in which these timestamps are specified.
498  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
499  * vop_time_increment_resolution and fixed_vop_rate
500  * (fixed_vop_rate == 0 implies that it is different from the framerate)
501  *
502  * - encoding: MUST be set by user.
503  * - decoding: the use of this field for decoding is deprecated.
504  * Use framerate instead.
505  */
507 
508  /**
509  * For some codecs, the time base is closer to the field rate than the frame rate.
510  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
511  * if no telecine is used ...
512  *
513  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
514  */
516 
517  /**
518  * Codec delay.
519  *
520  * Encoding: Number of frames delay there will be from the encoder input to
521  * the decoder output. (we assume the decoder matches the spec)
522  * Decoding: Number of frames delay in addition to what a standard decoder
523  * as specified in the spec would produce.
524  *
525  * Video:
526  * Number of frames the decoded output will be delayed relative to the
527  * encoded input.
528  *
529  * Audio:
530  * For encoding, this field is unused (see initial_padding).
531  *
532  * For decoding, this is the number of samples the decoder needs to
533  * output before the decoder's output is valid. When seeking, you should
534  * start decoding this many samples prior to your desired seek point.
535  *
536  * - encoding: Set by libavcodec.
537  * - decoding: Set by libavcodec.
538  */
539  int delay;
540 
541 
542  /* video only */
543  /**
544  * picture width / height.
545  *
546  * @note Those fields may not match the values of the last
547  * AVFrame output by avcodec_receive_frame() due frame
548  * reordering.
549  *
550  * - encoding: MUST be set by user.
551  * - decoding: May be set by the user before opening the decoder if known e.g.
552  * from the container. Some decoders will require the dimensions
553  * to be set by the caller. During decoding, the decoder may
554  * overwrite those values as required while parsing the data.
555  */
556  int width, height;
557 
558  /**
559  * Bitstream width / height, may be different from width/height e.g. when
560  * the decoded frame is cropped before being output or lowres is enabled.
561  *
562  * @note Those field may not match the value of the last
563  * AVFrame output by avcodec_receive_frame() due frame
564  * reordering.
565  *
566  * - encoding: unused
567  * - decoding: May be set by the user before opening the decoder if known
568  * e.g. from the container. During decoding, the decoder may
569  * overwrite those values as required while parsing the data.
570  */
572 
573  /**
574  * the number of pictures in a group of pictures, or 0 for intra_only
575  * - encoding: Set by user.
576  * - decoding: unused
577  */
578  int gop_size;
579 
580  /**
581  * Pixel format, see AV_PIX_FMT_xxx.
582  * May be set by the demuxer if known from headers.
583  * May be overridden by the decoder if it knows better.
584  *
585  * @note This field may not match the value of the last
586  * AVFrame output by avcodec_receive_frame() due frame
587  * reordering.
588  *
589  * - encoding: Set by user.
590  * - decoding: Set by user if known, overridden by libavcodec while
591  * parsing the data.
592  */
594 
595  /**
596  * If non NULL, 'draw_horiz_band' is called by the libavcodec
597  * decoder to draw a horizontal band. It improves cache usage. Not
598  * all codecs can do that. You must check the codec capabilities
599  * beforehand.
600  * When multithreading is used, it may be called from multiple threads
601  * at the same time; threads might draw different parts of the same AVFrame,
602  * or multiple AVFrames, and there is no guarantee that slices will be drawn
603  * in order.
604  * The function is also used by hardware acceleration APIs.
605  * It is called at least once during frame decoding to pass
606  * the data needed for hardware render.
607  * In that mode instead of pixel data, AVFrame points to
608  * a structure specific to the acceleration API. The application
609  * reads the structure and can change some fields to indicate progress
610  * or mark state.
611  * - encoding: unused
612  * - decoding: Set by user.
613  * @param height the height of the slice
614  * @param y the y position of the slice
615  * @param type 1->top field, 2->bottom field, 3->frame
616  * @param offset offset into the AVFrame.data from which the slice should be read
617  */
619  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
620  int y, int type, int height);
621 
622  /**
623  * Callback to negotiate the pixel format. Decoding only, may be set by the
624  * caller before avcodec_open2().
625  *
626  * Called by some decoders to select the pixel format that will be used for
627  * the output frames. This is mainly used to set up hardware acceleration,
628  * then the provided format list contains the corresponding hwaccel pixel
629  * formats alongside the "software" one. The software pixel format may also
630  * be retrieved from \ref sw_pix_fmt.
631  *
632  * This callback will be called when the coded frame properties (such as
633  * resolution, pixel format, etc.) change and more than one output format is
634  * supported for those new properties. If a hardware pixel format is chosen
635  * and initialization for it fails, the callback may be called again
636  * immediately.
637  *
638  * This callback may be called from different threads if the decoder is
639  * multi-threaded, but not from more than one thread simultaneously.
640  *
641  * @param fmt list of formats which may be used in the current
642  * configuration, terminated by AV_PIX_FMT_NONE.
643  * @warning Behavior is undefined if the callback returns a value other
644  * than one of the formats in fmt or AV_PIX_FMT_NONE.
645  * @return the chosen format or AV_PIX_FMT_NONE
646  */
647  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
648 
649  /**
650  * maximum number of B-frames between non-B-frames
651  * Note: The output will be delayed by max_b_frames+1 relative to the input.
652  * - encoding: Set by user.
653  * - decoding: unused
654  */
656 
657  /**
658  * qscale factor between IP and B-frames
659  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
660  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
661  * - encoding: Set by user.
662  * - decoding: unused
663  */
665 
666  /**
667  * qscale offset between IP and B-frames
668  * - encoding: Set by user.
669  * - decoding: unused
670  */
672 
673  /**
674  * Size of the frame reordering buffer in the decoder.
675  * For MPEG-2 it is 1 IPB or 0 low delay IP.
676  * - encoding: Set by libavcodec.
677  * - decoding: Set by libavcodec.
678  */
680 
681  /**
682  * qscale factor between P- and I-frames
683  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
684  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
685  * - encoding: Set by user.
686  * - decoding: unused
687  */
689 
690  /**
691  * qscale offset between P and I-frames
692  * - encoding: Set by user.
693  * - decoding: unused
694  */
696 
697  /**
698  * luminance masking (0-> disabled)
699  * - encoding: Set by user.
700  * - decoding: unused
701  */
703 
704  /**
705  * temporary complexity masking (0-> disabled)
706  * - encoding: Set by user.
707  * - decoding: unused
708  */
710 
711  /**
712  * spatial complexity masking (0-> disabled)
713  * - encoding: Set by user.
714  * - decoding: unused
715  */
717 
718  /**
719  * p block masking (0-> disabled)
720  * - encoding: Set by user.
721  * - decoding: unused
722  */
723  float p_masking;
724 
725  /**
726  * darkness masking (0-> disabled)
727  * - encoding: Set by user.
728  * - decoding: unused
729  */
731 
732  /**
733  * slice count
734  * - encoding: Set by libavcodec.
735  * - decoding: Set by user (or 0).
736  */
738 
739  /**
740  * slice offsets in the frame in bytes
741  * - encoding: Set/allocated by libavcodec.
742  * - decoding: Set/allocated by user (or NULL).
743  */
745 
746  /**
747  * sample aspect ratio (0 if unknown)
748  * That is the width of a pixel divided by the height of the pixel.
749  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
750  * - encoding: Set by user.
751  * - decoding: Set by libavcodec.
752  */
754 
755  /**
756  * motion estimation comparison function
757  * - encoding: Set by user.
758  * - decoding: unused
759  */
760  int me_cmp;
761  /**
762  * subpixel motion estimation comparison function
763  * - encoding: Set by user.
764  * - decoding: unused
765  */
767  /**
768  * macroblock comparison function (not supported yet)
769  * - encoding: Set by user.
770  * - decoding: unused
771  */
772  int mb_cmp;
773  /**
774  * interlaced DCT comparison function
775  * - encoding: Set by user.
776  * - decoding: unused
777  */
779 #define FF_CMP_SAD 0
780 #define FF_CMP_SSE 1
781 #define FF_CMP_SATD 2
782 #define FF_CMP_DCT 3
783 #define FF_CMP_PSNR 4
784 #define FF_CMP_BIT 5
785 #define FF_CMP_RD 6
786 #define FF_CMP_ZERO 7
787 #define FF_CMP_VSAD 8
788 #define FF_CMP_VSSE 9
789 #define FF_CMP_NSSE 10
790 #define FF_CMP_W53 11
791 #define FF_CMP_W97 12
792 #define FF_CMP_DCTMAX 13
793 #define FF_CMP_DCT264 14
794 #define FF_CMP_MEDIAN_SAD 15
795 #define FF_CMP_CHROMA 256
796 
797  /**
798  * ME diamond size & shape
799  * - encoding: Set by user.
800  * - decoding: unused
801  */
802  int dia_size;
803 
804  /**
805  * amount of previous MV predictors (2a+1 x 2a+1 square)
806  * - encoding: Set by user.
807  * - decoding: unused
808  */
810 
811  /**
812  * motion estimation prepass comparison function
813  * - encoding: Set by user.
814  * - decoding: unused
815  */
817 
818  /**
819  * ME prepass diamond size & shape
820  * - encoding: Set by user.
821  * - decoding: unused
822  */
824 
825  /**
826  * subpel ME quality
827  * - encoding: Set by user.
828  * - decoding: unused
829  */
831 
832  /**
833  * maximum motion estimation search range in subpel units
834  * If 0 then no limit.
835  *
836  * - encoding: Set by user.
837  * - decoding: unused
838  */
839  int me_range;
840 
841  /**
842  * slice flags
843  * - encoding: unused
844  * - decoding: Set by user.
845  */
847 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
848 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
849 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
850 
851  /**
852  * macroblock decision mode
853  * - encoding: Set by user.
854  * - decoding: unused
855  */
857 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
858 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
859 #define FF_MB_DECISION_RD 2 ///< rate distortion
860 
861  /**
862  * custom intra quantization matrix
863  * Must be allocated with the av_malloc() family of functions, and will be freed in
864  * avcodec_free_context().
865  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
866  * - decoding: Set/allocated/freed by libavcodec.
867  */
868  uint16_t *intra_matrix;
869 
870  /**
871  * custom inter quantization matrix
872  * Must be allocated with the av_malloc() family of functions, and will be freed in
873  * avcodec_free_context().
874  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
875  * - decoding: Set/allocated/freed by libavcodec.
876  */
877  uint16_t *inter_matrix;
878 
879  /**
880  * precision of the intra DC coefficient - 8
881  * - encoding: Set by user.
882  * - decoding: Set by libavcodec
883  */
885 
886  /**
887  * Number of macroblock rows at the top which are skipped.
888  * - encoding: unused
889  * - decoding: Set by user.
890  */
891  int skip_top;
892 
893  /**
894  * Number of macroblock rows at the bottom which are skipped.
895  * - encoding: unused
896  * - decoding: Set by user.
897  */
899 
900  /**
901  * minimum MB Lagrange multiplier
902  * - encoding: Set by user.
903  * - decoding: unused
904  */
905  int mb_lmin;
906 
907  /**
908  * maximum MB Lagrange multiplier
909  * - encoding: Set by user.
910  * - decoding: unused
911  */
912  int mb_lmax;
913 
914  /**
915  * - encoding: Set by user.
916  * - decoding: unused
917  */
919 
920  /**
921  * minimum GOP size
922  * - encoding: Set by user.
923  * - decoding: unused
924  */
926 
927  /**
928  * number of reference frames
929  * - encoding: Set by user.
930  * - decoding: Set by lavc.
931  */
932  int refs;
933 
934  /**
935  * Note: Value depends upon the compare function used for fullpel ME.
936  * - encoding: Set by user.
937  * - decoding: unused
938  */
940 
941  /**
942  * Chromaticity coordinates of the source primaries.
943  * - encoding: Set by user
944  * - decoding: Set by libavcodec
945  */
947 
948  /**
949  * Color Transfer Characteristic.
950  * - encoding: Set by user
951  * - decoding: Set by libavcodec
952  */
954 
955  /**
956  * YUV colorspace type.
957  * - encoding: Set by user
958  * - decoding: Set by libavcodec
959  */
961 
962  /**
963  * MPEG vs JPEG YUV range.
964  * - encoding: Set by user
965  * - decoding: Set by libavcodec
966  */
968 
969  /**
970  * This defines the location of chroma samples.
971  * - encoding: Set by user
972  * - decoding: Set by libavcodec
973  */
975 
976  /**
977  * Number of slices.
978  * Indicates number of picture subdivisions. Used for parallelized
979  * decoding.
980  * - encoding: Set by user
981  * - decoding: unused
982  */
983  int slices;
984 
985  /** Field order
986  * - encoding: set by libavcodec
987  * - decoding: Set by user.
988  */
990 
991  /* audio only */
992  int sample_rate; ///< samples per second
993  int channels; ///< number of audio channels
994 
995  /**
996  * audio sample format
997  * - encoding: Set by user.
998  * - decoding: Set by libavcodec.
999  */
1000  enum AVSampleFormat sample_fmt; ///< sample format
1001 
1002  /* The following data should not be initialized. */
1003  /**
1004  * Number of samples per channel in an audio frame.
1005  *
1006  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1007  * except the last must contain exactly frame_size samples per channel.
1008  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1009  * frame size is not restricted.
1010  * - decoding: may be set by some decoders to indicate constant frame size
1011  */
1013 
1014  /**
1015  * Frame counter, set by libavcodec.
1016  *
1017  * - decoding: total number of frames returned from the decoder so far.
1018  * - encoding: total number of frames passed to the encoder so far.
1019  *
1020  * @note the counter is not incremented if encoding/decoding resulted in
1021  * an error.
1022  */
1024 
1025  /**
1026  * number of bytes per packet if constant and known or 0
1027  * Used by some WAV based audio codecs.
1028  */
1030 
1031  /**
1032  * Audio cutoff bandwidth (0 means "automatic")
1033  * - encoding: Set by user.
1034  * - decoding: unused
1035  */
1036  int cutoff;
1037 
1038  /**
1039  * Audio channel layout.
1040  * - encoding: set by user.
1041  * - decoding: set by user, may be overwritten by libavcodec.
1042  */
1043  uint64_t channel_layout;
1044 
1045  /**
1046  * Request decoder to use this channel layout if it can (0 for default)
1047  * - encoding: unused
1048  * - decoding: Set by user.
1049  */
1051 
1052  /**
1053  * Type of service that the audio stream conveys.
1054  * - encoding: Set by user.
1055  * - decoding: Set by libavcodec.
1056  */
1058 
1059  /**
1060  * desired sample format
1061  * - encoding: Not used.
1062  * - decoding: Set by user.
1063  * Decoder will decode to this format if it can.
1064  */
1066 
1067  /**
1068  * This callback is called at the beginning of each frame to get data
1069  * buffer(s) for it. There may be one contiguous buffer for all the data or
1070  * there may be a buffer per each data plane or anything in between. What
1071  * this means is, you may set however many entries in buf[] you feel necessary.
1072  * Each buffer must be reference-counted using the AVBuffer API (see description
1073  * of buf[] below).
1074  *
1075  * The following fields will be set in the frame before this callback is
1076  * called:
1077  * - format
1078  * - width, height (video only)
1079  * - sample_rate, channel_layout, nb_samples (audio only)
1080  * Their values may differ from the corresponding values in
1081  * AVCodecContext. This callback must use the frame values, not the codec
1082  * context values, to calculate the required buffer size.
1083  *
1084  * This callback must fill the following fields in the frame:
1085  * - data[]
1086  * - linesize[]
1087  * - extended_data:
1088  * * if the data is planar audio with more than 8 channels, then this
1089  * callback must allocate and fill extended_data to contain all pointers
1090  * to all data planes. data[] must hold as many pointers as it can.
1091  * extended_data must be allocated with av_malloc() and will be freed in
1092  * av_frame_unref().
1093  * * otherwise extended_data must point to data
1094  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1095  * the frame's data and extended_data pointers must be contained in these. That
1096  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1097  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1098  * and av_buffer_ref().
1099  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1100  * this callback and filled with the extra buffers if there are more
1101  * buffers than buf[] can hold. extended_buf will be freed in
1102  * av_frame_unref().
1103  *
1104  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1105  * avcodec_default_get_buffer2() instead of providing buffers allocated by
1106  * some other means.
1107  *
1108  * Each data plane must be aligned to the maximum required by the target
1109  * CPU.
1110  *
1111  * @see avcodec_default_get_buffer2()
1112  *
1113  * Video:
1114  *
1115  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1116  * (read and/or written to if it is writable) later by libavcodec.
1117  *
1118  * avcodec_align_dimensions2() should be used to find the required width and
1119  * height, as they normally need to be rounded up to the next multiple of 16.
1120  *
1121  * Some decoders do not support linesizes changing between frames.
1122  *
1123  * If frame multithreading is used, this callback may be called from a
1124  * different thread, but not from more than one at once. Does not need to be
1125  * reentrant.
1126  *
1127  * @see avcodec_align_dimensions2()
1128  *
1129  * Audio:
1130  *
1131  * Decoders request a buffer of a particular size by setting
1132  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1133  * however, utilize only part of the buffer by setting AVFrame.nb_samples
1134  * to a smaller value in the output frame.
1135  *
1136  * As a convenience, av_samples_get_buffer_size() and
1137  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1138  * functions to find the required data size and to fill data pointers and
1139  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1140  * since all planes must be the same size.
1141  *
1142  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1143  *
1144  * - encoding: unused
1145  * - decoding: Set by libavcodec, user can override.
1146  */
1148 
1149  /* - encoding parameters */
1150  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1151  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1152 
1153  /**
1154  * minimum quantizer
1155  * - encoding: Set by user.
1156  * - decoding: unused
1157  */
1158  int qmin;
1159 
1160  /**
1161  * maximum quantizer
1162  * - encoding: Set by user.
1163  * - decoding: unused
1164  */
1165  int qmax;
1166 
1167  /**
1168  * maximum quantizer difference between frames
1169  * - encoding: Set by user.
1170  * - decoding: unused
1171  */
1173 
1174  /**
1175  * decoder bitstream buffer size
1176  * - encoding: Set by user.
1177  * - decoding: unused
1178  */
1180 
1181  /**
1182  * ratecontrol override, see RcOverride
1183  * - encoding: Allocated/set/freed by user.
1184  * - decoding: unused
1185  */
1188 
1189  /**
1190  * maximum bitrate
1191  * - encoding: Set by user.
1192  * - decoding: Set by user, may be overwritten by libavcodec.
1193  */
1194  int64_t rc_max_rate;
1195 
1196  /**
1197  * minimum bitrate
1198  * - encoding: Set by user.
1199  * - decoding: unused
1200  */
1201  int64_t rc_min_rate;
1202 
1203  /**
1204  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1205  * - encoding: Set by user.
1206  * - decoding: unused.
1207  */
1209 
1210  /**
1211  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1212  * - encoding: Set by user.
1213  * - decoding: unused.
1214  */
1216 
1217  /**
1218  * Number of bits which should be loaded into the rc buffer before decoding starts.
1219  * - encoding: Set by user.
1220  * - decoding: unused
1221  */
1223 
1224  /**
1225  * trellis RD quantization
1226  * - encoding: Set by user.
1227  * - decoding: unused
1228  */
1229  int trellis;
1230 
1231  /**
1232  * pass1 encoding statistics output buffer
1233  * - encoding: Set by libavcodec.
1234  * - decoding: unused
1235  */
1236  char *stats_out;
1237 
1238  /**
1239  * pass2 encoding statistics input buffer
1240  * Concatenated stuff from stats_out of pass1 should be placed here.
1241  * - encoding: Allocated/set/freed by user.
1242  * - decoding: unused
1243  */
1244  char *stats_in;
1245 
1246  /**
1247  * Work around bugs in encoders which sometimes cannot be detected automatically.
1248  * - encoding: Set by user
1249  * - decoding: Set by user
1250  */
1252 #define FF_BUG_AUTODETECT 1 ///< autodetection
1253 #define FF_BUG_XVID_ILACE 4
1254 #define FF_BUG_UMP4 8
1255 #define FF_BUG_NO_PADDING 16
1256 #define FF_BUG_AMV 32
1257 #define FF_BUG_QPEL_CHROMA 64
1258 #define FF_BUG_STD_QPEL 128
1259 #define FF_BUG_QPEL_CHROMA2 256
1260 #define FF_BUG_DIRECT_BLOCKSIZE 512
1261 #define FF_BUG_EDGE 1024
1262 #define FF_BUG_HPEL_CHROMA 2048
1263 #define FF_BUG_DC_CLIP 4096
1264 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1265 #define FF_BUG_TRUNCATED 16384
1266 #define FF_BUG_IEDGE 32768
1267 
1268  /**
1269  * strictly follow the standard (MPEG-4, ...).
1270  * - encoding: Set by user.
1271  * - decoding: Set by user.
1272  * Setting this to STRICT or higher means the encoder and decoder will
1273  * generally do stupid things, whereas setting it to unofficial or lower
1274  * will mean the encoder might produce output that is not supported by all
1275  * spec-compliant decoders. Decoders don't differentiate between normal,
1276  * unofficial and experimental (that is, they always try to decode things
1277  * when they can) unless they are explicitly asked to behave stupidly
1278  * (=strictly conform to the specs)
1279  */
1281 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
1282 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
1283 #define FF_COMPLIANCE_NORMAL 0
1284 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
1285 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
1286 
1287  /**
1288  * error concealment flags
1289  * - encoding: unused
1290  * - decoding: Set by user.
1291  */
1293 #define FF_EC_GUESS_MVS 1
1294 #define FF_EC_DEBLOCK 2
1295 #define FF_EC_FAVOR_INTER 256
1296 
1297  /**
1298  * debug
1299  * - encoding: Set by user.
1300  * - decoding: Set by user.
1301  */
1302  int debug;
1303 #define FF_DEBUG_PICT_INFO 1
1304 #define FF_DEBUG_RC 2
1305 #define FF_DEBUG_BITSTREAM 4
1306 #define FF_DEBUG_MB_TYPE 8
1307 #define FF_DEBUG_QP 16
1308 #define FF_DEBUG_DCT_COEFF 0x00000040
1309 #define FF_DEBUG_SKIP 0x00000080
1310 #define FF_DEBUG_STARTCODE 0x00000100
1311 #define FF_DEBUG_ER 0x00000400
1312 #define FF_DEBUG_MMCO 0x00000800
1313 #define FF_DEBUG_BUGS 0x00001000
1314 #define FF_DEBUG_BUFFERS 0x00008000
1315 #define FF_DEBUG_THREADS 0x00010000
1316 #define FF_DEBUG_GREEN_MD 0x00800000
1317 #define FF_DEBUG_NOMC 0x01000000
1318 
1319  /**
1320  * Error recognition; may misdetect some more or less valid parts as errors.
1321  * - encoding: Set by user.
1322  * - decoding: Set by user.
1323  */
1325 
1326 /**
1327  * Verify checksums embedded in the bitstream (could be of either encoded or
1328  * decoded data, depending on the codec) and print an error message on mismatch.
1329  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
1330  * decoder returning an error.
1331  */
1332 #define AV_EF_CRCCHECK (1<<0)
1333 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
1334 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
1335 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
1336 
1337 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
1338 #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
1339 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
1340 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
1341 
1342 
1343  /**
1344  * opaque 64-bit number (generally a PTS) that will be reordered and
1345  * output in AVFrame.reordered_opaque
1346  * - encoding: Set by libavcodec to the reordered_opaque of the input
1347  * frame corresponding to the last returned packet. Only
1348  * supported by encoders with the
1349  * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1350  * - decoding: Set by user.
1351  */
1353 
1354  /**
1355  * Hardware accelerator in use
1356  * - encoding: unused.
1357  * - decoding: Set by libavcodec
1358  */
1359  const struct AVHWAccel *hwaccel;
1360 
1361  /**
1362  * Hardware accelerator context.
1363  * For some hardware accelerators, a global context needs to be
1364  * provided by the user. In that case, this holds display-dependent
1365  * data FFmpeg cannot instantiate itself. Please refer to the
1366  * FFmpeg HW accelerator documentation to know how to fill this.
1367  * - encoding: unused
1368  * - decoding: Set by user
1369  */
1371 
1372  /**
1373  * error
1374  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1375  * - decoding: unused
1376  */
1378 
1379  /**
1380  * DCT algorithm, see FF_DCT_* below
1381  * - encoding: Set by user.
1382  * - decoding: unused
1383  */
1385 #define FF_DCT_AUTO 0
1386 #define FF_DCT_FASTINT 1
1387 #define FF_DCT_INT 2
1388 #define FF_DCT_MMX 3
1389 #define FF_DCT_ALTIVEC 5
1390 #define FF_DCT_FAAN 6
1391 
1392  /**
1393  * IDCT algorithm, see FF_IDCT_* below.
1394  * - encoding: Set by user.
1395  * - decoding: Set by user.
1396  */
1398 #define FF_IDCT_AUTO 0
1399 #define FF_IDCT_INT 1
1400 #define FF_IDCT_SIMPLE 2
1401 #define FF_IDCT_SIMPLEMMX 3
1402 #define FF_IDCT_ARM 7
1403 #define FF_IDCT_ALTIVEC 8
1404 #define FF_IDCT_SIMPLEARM 10
1405 #define FF_IDCT_XVID 14
1406 #define FF_IDCT_SIMPLEARMV5TE 16
1407 #define FF_IDCT_SIMPLEARMV6 17
1408 #define FF_IDCT_FAAN 20
1409 #define FF_IDCT_SIMPLENEON 22
1410 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
1411 #define FF_IDCT_SIMPLEAUTO 128
1412 
1413  /**
1414  * bits per sample/pixel from the demuxer (needed for huffyuv).
1415  * - encoding: Set by libavcodec.
1416  * - decoding: Set by user.
1417  */
1419 
1420  /**
1421  * Bits per sample/pixel of internal libavcodec pixel/sample format.
1422  * - encoding: set by user.
1423  * - decoding: set by libavcodec.
1424  */
1426 
1427  /**
1428  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1429  * - encoding: unused
1430  * - decoding: Set by user.
1431  */
1432  int lowres;
1433 
1434  /**
1435  * thread count
1436  * is used to decide how many independent tasks should be passed to execute()
1437  * - encoding: Set by user.
1438  * - decoding: Set by user.
1439  */
1441 
1442  /**
1443  * Which multithreading methods to use.
1444  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1445  * so clients which cannot provide future frames should not use it.
1446  *
1447  * - encoding: Set by user, otherwise the default is used.
1448  * - decoding: Set by user, otherwise the default is used.
1449  */
1451 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1452 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1453 
1454  /**
1455  * Which multithreading methods are in use by the codec.
1456  * - encoding: Set by libavcodec.
1457  * - decoding: Set by libavcodec.
1458  */
1460 
1461 #if FF_API_THREAD_SAFE_CALLBACKS
1462  /**
1463  * Set by the client if its custom get_buffer() callback can be called
1464  * synchronously from another thread, which allows faster multithreaded decoding.
1465  * draw_horiz_band() will be called from other threads regardless of this setting.
1466  * Ignored if the default get_buffer() is used.
1467  * - encoding: Set by user.
1468  * - decoding: Set by user.
1469  *
1470  * @deprecated the custom get_buffer2() callback should always be
1471  * thread-safe. Thread-unsafe get_buffer2() implementations will be
1472  * invalid starting with LIBAVCODEC_VERSION_MAJOR=60; in other words,
1473  * libavcodec will behave as if this field was always set to 1.
1474  * Callers that want to be forward compatible with future libavcodec
1475  * versions should wrap access to this field in
1476  * #if LIBAVCODEC_VERSION_MAJOR < 60
1477  */
1480 #endif
1481 
1482  /**
1483  * The codec may call this to execute several independent things.
1484  * It will return only after finishing all tasks.
1485  * The user may replace this with some multithreaded implementation,
1486  * the default implementation will execute the parts serially.
1487  * @param count the number of things to execute
1488  * - encoding: Set by libavcodec, user can override.
1489  * - decoding: Set by libavcodec, user can override.
1490  */
1491  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1492 
1493  /**
1494  * The codec may call this to execute several independent things.
1495  * It will return only after finishing all tasks.
1496  * The user may replace this with some multithreaded implementation,
1497  * the default implementation will execute the parts serially.
1498  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
1499  * @param c context passed also to func
1500  * @param count the number of things to execute
1501  * @param arg2 argument passed unchanged to func
1502  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1503  * @param func function that will be called count times, with jobnr from 0 to count-1.
1504  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1505  * two instances of func executing at the same time will have the same threadnr.
1506  * @return always 0 currently, but code should handle a future improvement where when any call to func
1507  * returns < 0 no further calls to func may be done and < 0 is returned.
1508  * - encoding: Set by libavcodec, user can override.
1509  * - decoding: Set by libavcodec, user can override.
1510  */
1511  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1512 
1513  /**
1514  * noise vs. sse weight for the nsse comparison function
1515  * - encoding: Set by user.
1516  * - decoding: unused
1517  */
1519 
1520  /**
1521  * profile
1522  * - encoding: Set by user.
1523  * - decoding: Set by libavcodec.
1524  */
1525  int profile;
1526 #define FF_PROFILE_UNKNOWN -99
1527 #define FF_PROFILE_RESERVED -100
1528 
1529 #define FF_PROFILE_AAC_MAIN 0
1530 #define FF_PROFILE_AAC_LOW 1
1531 #define FF_PROFILE_AAC_SSR 2
1532 #define FF_PROFILE_AAC_LTP 3
1533 #define FF_PROFILE_AAC_HE 4
1534 #define FF_PROFILE_AAC_HE_V2 28
1535 #define FF_PROFILE_AAC_LD 22
1536 #define FF_PROFILE_AAC_ELD 38
1537 #define FF_PROFILE_MPEG2_AAC_LOW 128
1538 #define FF_PROFILE_MPEG2_AAC_HE 131
1539 
1540 #define FF_PROFILE_DNXHD 0
1541 #define FF_PROFILE_DNXHR_LB 1
1542 #define FF_PROFILE_DNXHR_SQ 2
1543 #define FF_PROFILE_DNXHR_HQ 3
1544 #define FF_PROFILE_DNXHR_HQX 4
1545 #define FF_PROFILE_DNXHR_444 5
1546 
1547 #define FF_PROFILE_DTS 20
1548 #define FF_PROFILE_DTS_ES 30
1549 #define FF_PROFILE_DTS_96_24 40
1550 #define FF_PROFILE_DTS_HD_HRA 50
1551 #define FF_PROFILE_DTS_HD_MA 60
1552 #define FF_PROFILE_DTS_EXPRESS 70
1553 
1554 #define FF_PROFILE_MPEG2_422 0
1555 #define FF_PROFILE_MPEG2_HIGH 1
1556 #define FF_PROFILE_MPEG2_SS 2
1557 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1558 #define FF_PROFILE_MPEG2_MAIN 4
1559 #define FF_PROFILE_MPEG2_SIMPLE 5
1560 
1561 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1562 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1563 
1564 #define FF_PROFILE_H264_BASELINE 66
1565 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1566 #define FF_PROFILE_H264_MAIN 77
1567 #define FF_PROFILE_H264_EXTENDED 88
1568 #define FF_PROFILE_H264_HIGH 100
1569 #define FF_PROFILE_H264_HIGH_10 110
1570 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1571 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1572 #define FF_PROFILE_H264_HIGH_422 122
1573 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1574 #define FF_PROFILE_H264_STEREO_HIGH 128
1575 #define FF_PROFILE_H264_HIGH_444 144
1576 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1577 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1578 #define FF_PROFILE_H264_CAVLC_444 44
1579 
1580 #define FF_PROFILE_VC1_SIMPLE 0
1581 #define FF_PROFILE_VC1_MAIN 1
1582 #define FF_PROFILE_VC1_COMPLEX 2
1583 #define FF_PROFILE_VC1_ADVANCED 3
1584 
1585 #define FF_PROFILE_MPEG4_SIMPLE 0
1586 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1587 #define FF_PROFILE_MPEG4_CORE 2
1588 #define FF_PROFILE_MPEG4_MAIN 3
1589 #define FF_PROFILE_MPEG4_N_BIT 4
1590 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1591 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1592 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1593 #define FF_PROFILE_MPEG4_HYBRID 8
1594 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1595 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1596 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1597 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1598 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1599 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1600 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1601 
1602 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1603 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1604 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1605 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1606 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1607 
1608 #define FF_PROFILE_VP9_0 0
1609 #define FF_PROFILE_VP9_1 1
1610 #define FF_PROFILE_VP9_2 2
1611 #define FF_PROFILE_VP9_3 3
1612 
1613 #define FF_PROFILE_HEVC_MAIN 1
1614 #define FF_PROFILE_HEVC_MAIN_10 2
1615 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1616 #define FF_PROFILE_HEVC_REXT 4
1617 
1618 #define FF_PROFILE_VVC_MAIN_10 1
1619 #define FF_PROFILE_VVC_MAIN_10_444 33
1620 
1621 #define FF_PROFILE_AV1_MAIN 0
1622 #define FF_PROFILE_AV1_HIGH 1
1623 #define FF_PROFILE_AV1_PROFESSIONAL 2
1624 
1625 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1626 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1627 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1628 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1629 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1630 
1631 #define FF_PROFILE_SBC_MSBC 1
1632 
1633 #define FF_PROFILE_PRORES_PROXY 0
1634 #define FF_PROFILE_PRORES_LT 1
1635 #define FF_PROFILE_PRORES_STANDARD 2
1636 #define FF_PROFILE_PRORES_HQ 3
1637 #define FF_PROFILE_PRORES_4444 4
1638 #define FF_PROFILE_PRORES_XQ 5
1639 
1640 #define FF_PROFILE_ARIB_PROFILE_A 0
1641 #define FF_PROFILE_ARIB_PROFILE_C 1
1642 
1643 #define FF_PROFILE_KLVA_SYNC 0
1644 #define FF_PROFILE_KLVA_ASYNC 1
1645 
1646  /**
1647  * level
1648  * - encoding: Set by user.
1649  * - decoding: Set by libavcodec.
1650  */
1651  int level;
1652 #define FF_LEVEL_UNKNOWN -99
1653 
1654  /**
1655  * Skip loop filtering for selected frames.
1656  * - encoding: unused
1657  * - decoding: Set by user.
1658  */
1660 
1661  /**
1662  * Skip IDCT/dequantization for selected frames.
1663  * - encoding: unused
1664  * - decoding: Set by user.
1665  */
1667 
1668  /**
1669  * Skip decoding for selected frames.
1670  * - encoding: unused
1671  * - decoding: Set by user.
1672  */
1674 
1675  /**
1676  * Header containing style information for text subtitles.
1677  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
1678  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
1679  * the Format line following. It shouldn't include any Dialogue line.
1680  * - encoding: Set/allocated/freed by user (before avcodec_open2())
1681  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
1682  */
1685 
1686  /**
1687  * Audio only. The number of "priming" samples (padding) inserted by the
1688  * encoder at the beginning of the audio. I.e. this number of leading
1689  * decoded samples must be discarded by the caller to get the original audio
1690  * without leading padding.
1691  *
1692  * - decoding: unused
1693  * - encoding: Set by libavcodec. The timestamps on the output packets are
1694  * adjusted by the encoder so that they always refer to the
1695  * first sample of the data actually contained in the packet,
1696  * including any added padding. E.g. if the timebase is
1697  * 1/samplerate and the timestamp of the first input sample is
1698  * 0, the timestamp of the first output packet will be
1699  * -initial_padding.
1700  */
1702 
1703  /**
1704  * - decoding: For codecs that store a framerate value in the compressed
1705  * bitstream, the decoder may export it here. { 0, 1} when
1706  * unknown.
1707  * - encoding: May be used to signal the framerate of CFR content to an
1708  * encoder.
1709  */
1711 
1712  /**
1713  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
1714  * - encoding: unused.
1715  * - decoding: Set by libavcodec before calling get_format()
1716  */
1718 
1719  /**
1720  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
1721  * - encoding unused.
1722  * - decoding set by user.
1723  */
1725 
1726  /**
1727  * AVCodecDescriptor
1728  * - encoding: unused.
1729  * - decoding: set by libavcodec.
1730  */
1732 
1733  /**
1734  * Current statistics for PTS correction.
1735  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
1736  * - encoding: unused
1737  */
1738  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
1739  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
1740  int64_t pts_correction_last_pts; /// PTS of the last frame
1741  int64_t pts_correction_last_dts; /// DTS of the last frame
1742 
1743  /**
1744  * Character encoding of the input subtitles file.
1745  * - decoding: set by user
1746  * - encoding: unused
1747  */
1749 
1750  /**
1751  * Subtitles character encoding mode. Formats or codecs might be adjusting
1752  * this setting (if they are doing the conversion themselves for instance).
1753  * - decoding: set by libavcodec
1754  * - encoding: unused
1755  */
1757 #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)
1758 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
1759 #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
1760 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
1761 
1762  /**
1763  * Skip processing alpha if supported by codec.
1764  * Note that if the format uses pre-multiplied alpha (common with VP6,
1765  * and recommended due to better video quality/compression)
1766  * the image will look as if alpha-blended onto a black background.
1767  * However for formats that do not use pre-multiplied alpha
1768  * there might be serious artefacts (though e.g. libswscale currently
1769  * assumes pre-multiplied alpha anyway).
1770  *
1771  * - decoding: set by user
1772  * - encoding: unused
1773  */
1775 
1776  /**
1777  * Number of samples to skip after a discontinuity
1778  * - decoding: unused
1779  * - encoding: set by libavcodec
1780  */
1782 
1783 #if FF_API_DEBUG_MV
1784  /**
1785  * @deprecated unused
1786  */
1789 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
1790 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
1791 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
1792 #endif
1793 
1794  /**
1795  * custom intra quantization matrix
1796  * - encoding: Set by user, can be NULL.
1797  * - decoding: unused.
1798  */
1800 
1801  /**
1802  * dump format separator.
1803  * can be ", " or "\n " or anything else
1804  * - encoding: Set by user.
1805  * - decoding: Set by user.
1806  */
1807  uint8_t *dump_separator;
1808 
1809  /**
1810  * ',' separated list of allowed decoders.
1811  * If NULL then all are allowed
1812  * - encoding: unused
1813  * - decoding: set by user
1814  */
1816 
1817  /**
1818  * Properties of the stream that gets decoded
1819  * - encoding: unused
1820  * - decoding: set by libavcodec
1821  */
1822  unsigned properties;
1823 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
1824 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
1825 #define FF_CODEC_PROPERTY_FILM_GRAIN 0x00000004
1826 
1827  /**
1828  * Additional data associated with the entire coded stream.
1829  *
1830  * - decoding: unused
1831  * - encoding: may be set by libavcodec after avcodec_open2().
1832  */
1835 
1836  /**
1837  * A reference to the AVHWFramesContext describing the input (for encoding)
1838  * or output (decoding) frames. The reference is set by the caller and
1839  * afterwards owned (and freed) by libavcodec - it should never be read by
1840  * the caller after being set.
1841  *
1842  * - decoding: This field should be set by the caller from the get_format()
1843  * callback. The previous reference (if any) will always be
1844  * unreffed by libavcodec before the get_format() call.
1845  *
1846  * If the default get_buffer2() is used with a hwaccel pixel
1847  * format, then this AVHWFramesContext will be used for
1848  * allocating the frame buffers.
1849  *
1850  * - encoding: For hardware encoders configured to use a hwaccel pixel
1851  * format, this field should be set by the caller to a reference
1852  * to the AVHWFramesContext describing input frames.
1853  * AVHWFramesContext.format must be equal to
1854  * AVCodecContext.pix_fmt.
1855  *
1856  * This field should be set before avcodec_open2() is called.
1857  */
1859 
1860 #if FF_API_SUB_TEXT_FORMAT
1861  /**
1862  * @deprecated unused
1863  */
1866 #define FF_SUB_TEXT_FMT_ASS 0
1867 #endif
1868 
1869  /**
1870  * Audio only. The amount of padding (in samples) appended by the encoder to
1871  * the end of the audio. I.e. this number of decoded samples must be
1872  * discarded by the caller from the end of the stream to get the original
1873  * audio without any trailing padding.
1874  *
1875  * - decoding: unused
1876  * - encoding: unused
1877  */
1879 
1880  /**
1881  * The number of pixels per image to maximally accept.
1882  *
1883  * - decoding: set by user
1884  * - encoding: set by user
1885  */
1886  int64_t max_pixels;
1887 
1888  /**
1889  * A reference to the AVHWDeviceContext describing the device which will
1890  * be used by a hardware encoder/decoder. The reference is set by the
1891  * caller and afterwards owned (and freed) by libavcodec.
1892  *
1893  * This should be used if either the codec device does not require
1894  * hardware frames or any that are used are to be allocated internally by
1895  * libavcodec. If the user wishes to supply any of the frames used as
1896  * encoder input or decoder output then hw_frames_ctx should be used
1897  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
1898  * field will be ignored while decoding the associated stream segment, but
1899  * may again be used on a following one after another get_format() call.
1900  *
1901  * For both encoders and decoders this field should be set before
1902  * avcodec_open2() is called and must not be written to thereafter.
1903  *
1904  * Note that some decoders may require this field to be set initially in
1905  * order to support hw_frames_ctx at all - in that case, all frames
1906  * contexts used must be created on the same device.
1907  */
1909 
1910  /**
1911  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
1912  * decoding (if active).
1913  * - encoding: unused
1914  * - decoding: Set by user (either before avcodec_open2(), or in the
1915  * AVCodecContext.get_format callback)
1916  */
1918 
1919  /**
1920  * Video decoding only. Certain video codecs support cropping, meaning that
1921  * only a sub-rectangle of the decoded frame is intended for display. This
1922  * option controls how cropping is handled by libavcodec.
1923  *
1924  * When set to 1 (the default), libavcodec will apply cropping internally.
1925  * I.e. it will modify the output frame width/height fields and offset the
1926  * data pointers (only by as much as possible while preserving alignment, or
1927  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
1928  * the frames output by the decoder refer only to the cropped area. The
1929  * crop_* fields of the output frames will be zero.
1930  *
1931  * When set to 0, the width/height fields of the output frames will be set
1932  * to the coded dimensions and the crop_* fields will describe the cropping
1933  * rectangle. Applying the cropping is left to the caller.
1934  *
1935  * @warning When hardware acceleration with opaque output frames is used,
1936  * libavcodec is unable to apply cropping from the top/left border.
1937  *
1938  * @note when this option is set to zero, the width/height fields of the
1939  * AVCodecContext and output AVFrames have different meanings. The codec
1940  * context fields store display dimensions (with the coded dimensions in
1941  * coded_width/height), while the frame fields store the coded dimensions
1942  * (with the display dimensions being determined by the crop_* fields).
1943  */
1945 
1946  /*
1947  * Video decoding only. Sets the number of extra hardware frames which
1948  * the decoder will allocate for use by the caller. This must be set
1949  * before avcodec_open2() is called.
1950  *
1951  * Some hardware decoders require all frames that they will use for
1952  * output to be defined in advance before decoding starts. For such
1953  * decoders, the hardware frame pool must therefore be of a fixed size.
1954  * The extra frames set here are on top of any number that the decoder
1955  * needs internally in order to operate normally (for example, frames
1956  * used as reference pictures).
1957  */
1959 
1960  /**
1961  * The percentage of damaged samples to discard a frame.
1962  *
1963  * - decoding: set by user
1964  * - encoding: unused
1965  */
1967 
1968  /**
1969  * The number of samples per frame to maximally accept.
1970  *
1971  * - decoding: set by user
1972  * - encoding: set by user
1973  */
1974  int64_t max_samples;
1975 
1976  /**
1977  * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
1978  * metadata exported in frame, packet, or coded stream side data by
1979  * decoders and encoders.
1980  *
1981  * - decoding: set by user
1982  * - encoding: set by user
1983  */
1985 
1986  /**
1987  * This callback is called at the beginning of each packet to get a data
1988  * buffer for it.
1989  *
1990  * The following field will be set in the packet before this callback is
1991  * called:
1992  * - size
1993  * This callback must use the above value to calculate the required buffer size,
1994  * which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
1995  *
1996  * In some specific cases, the encoder may not use the entire buffer allocated by this
1997  * callback. This will be reflected in the size value in the packet once returned by
1998  * avcodec_receive_packet().
1999  *
2000  * This callback must fill the following fields in the packet:
2001  * - data: alignment requirements for AVPacket apply, if any. Some architectures and
2002  * encoders may benefit from having aligned data.
2003  * - buf: must contain a pointer to an AVBufferRef structure. The packet's
2004  * data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
2005  * and av_buffer_ref().
2006  *
2007  * If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2008  * avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2009  * some other means.
2010  *
2011  * The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2012  * They may be used for example to hint what use the buffer may get after being
2013  * created.
2014  * Implementations of this callback may ignore flags they don't understand.
2015  * If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2016  * (read and/or written to if it is writable) later by libavcodec.
2017  *
2018  * This callback must be thread-safe, as when frame threading is used, it may
2019  * be called from multiple threads simultaneously.
2020  *
2021  * @see avcodec_default_get_encode_buffer()
2022  *
2023  * - encoding: Set by libavcodec, user can override.
2024  * - decoding: unused
2025  */
2027 } AVCodecContext;
2028 
2029 struct MpegEncContext;
2030 
2031 /**
2032  * @defgroup lavc_hwaccel AVHWAccel
2033  *
2034  * @note Nothing in this structure should be accessed by the user. At some
2035  * point in future it will not be externally visible at all.
2036  *
2037  * @{
2038  */
2039 typedef struct AVHWAccel {
2040  /**
2041  * Name of the hardware accelerated codec.
2042  * The name is globally unique among encoders and among decoders (but an
2043  * encoder and a decoder can share the same name).
2044  */
2045  const char *name;
2046 
2047  /**
2048  * Type of codec implemented by the hardware accelerator.
2049  *
2050  * See AVMEDIA_TYPE_xxx
2051  */
2053 
2054  /**
2055  * Codec implemented by the hardware accelerator.
2056  *
2057  * See AV_CODEC_ID_xxx
2058  */
2060 
2061  /**
2062  * Supported pixel format.
2063  *
2064  * Only hardware accelerated formats are supported here.
2065  */
2067 
2068  /**
2069  * Hardware accelerated codec capabilities.
2070  * see AV_HWACCEL_CODEC_CAP_*
2071  */
2073 
2074  /*****************************************************************
2075  * No fields below this line are part of the public API. They
2076  * may not be used outside of libavcodec and can be changed and
2077  * removed at will.
2078  * New public fields should be added right above.
2079  *****************************************************************
2080  */
2081 
2082  /**
2083  * Allocate a custom buffer
2084  */
2086 
2087  /**
2088  * Called at the beginning of each frame or field picture.
2089  *
2090  * Meaningful frame information (codec specific) is guaranteed to
2091  * be parsed at this point. This function is mandatory.
2092  *
2093  * Note that buf can be NULL along with buf_size set to 0.
2094  * Otherwise, this means the whole frame is available at this point.
2095  *
2096  * @param avctx the codec context
2097  * @param buf the frame data buffer base
2098  * @param buf_size the size of the frame in bytes
2099  * @return zero if successful, a negative value otherwise
2100  */
2101  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2102 
2103  /**
2104  * Callback for parameter data (SPS/PPS/VPS etc).
2105  *
2106  * Useful for hardware decoders which keep persistent state about the
2107  * video parameters, and need to receive any changes to update that state.
2108  *
2109  * @param avctx the codec context
2110  * @param type the nal unit type
2111  * @param buf the nal unit data buffer
2112  * @param buf_size the size of the nal unit in bytes
2113  * @return zero if successful, a negative value otherwise
2114  */
2115  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
2116 
2117  /**
2118  * Callback for each slice.
2119  *
2120  * Meaningful slice information (codec specific) is guaranteed to
2121  * be parsed at this point. This function is mandatory.
2122  * The only exception is XvMC, that works on MB level.
2123  *
2124  * @param avctx the codec context
2125  * @param buf the slice data buffer base
2126  * @param buf_size the size of the slice in bytes
2127  * @return zero if successful, a negative value otherwise
2128  */
2129  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2130 
2131  /**
2132  * Called at the end of each frame or field picture.
2133  *
2134  * The whole picture is parsed at this point and can now be sent
2135  * to the hardware accelerator. This function is mandatory.
2136  *
2137  * @param avctx the codec context
2138  * @return zero if successful, a negative value otherwise
2139  */
2141 
2142  /**
2143  * Size of per-frame hardware accelerator private data.
2144  *
2145  * Private data is allocated with av_mallocz() before
2146  * AVCodecContext.get_buffer() and deallocated after
2147  * AVCodecContext.release_buffer().
2148  */
2150 
2151  /**
2152  * Called for every Macroblock in a slice.
2153  *
2154  * XvMC uses it to replace the ff_mpv_reconstruct_mb().
2155  * Instead of decoding to raw picture, MB parameters are
2156  * stored in an array provided by the video driver.
2157  *
2158  * @param s the mpeg context
2159  */
2160  void (*decode_mb)(struct MpegEncContext *s);
2161 
2162  /**
2163  * Initialize the hwaccel private data.
2164  *
2165  * This will be called from ff_get_format(), after hwaccel and
2166  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
2167  * is allocated.
2168  */
2170 
2171  /**
2172  * Uninitialize the hwaccel private data.
2173  *
2174  * This will be called from get_format() or avcodec_close(), after hwaccel
2175  * and hwaccel_context are already uninitialized.
2176  */
2178 
2179  /**
2180  * Size of the private data to allocate in
2181  * AVCodecInternal.hwaccel_priv_data.
2182  */
2184 
2185  /**
2186  * Internal hwaccel capabilities.
2187  */
2189 
2190  /**
2191  * Fill the given hw_frames context with current codec parameters. Called
2192  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
2193  * details.
2194  *
2195  * This CAN be called before AVHWAccel.init is called, and you must assume
2196  * that avctx->hwaccel_priv_data is invalid.
2197  */
2199 } AVHWAccel;
2200 
2201 /**
2202  * HWAccel is experimental and is thus avoided in favor of non experimental
2203  * codecs
2204  */
2205 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2206 
2207 /**
2208  * Hardware acceleration should be used for decoding even if the codec level
2209  * used is unknown or higher than the maximum supported level reported by the
2210  * hardware driver.
2211  *
2212  * It's generally a good idea to pass this flag unless you have a specific
2213  * reason not to, as hardware tends to under-report supported levels.
2214  */
2215 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2216 
2217 /**
2218  * Hardware acceleration can output YUV pixel formats with a different chroma
2219  * sampling than 4:2:0 and/or other than 8 bits per component.
2220  */
2221 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2222 
2223 /**
2224  * Hardware acceleration should still be attempted for decoding when the
2225  * codec profile does not match the reported capabilities of the hardware.
2226  *
2227  * For example, this can be used to try to decode baseline profile H.264
2228  * streams in hardware - it will often succeed, because many streams marked
2229  * as baseline profile actually conform to constrained baseline profile.
2230  *
2231  * @warning If the stream is actually not supported then the behaviour is
2232  * undefined, and may include returning entirely incorrect output
2233  * while indicating success.
2234  */
2235 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2236 
2237 /**
2238  * @}
2239  */
2240 
2243 
2244  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2245 
2246  /**
2247  * Plain text, the text field must be set by the decoder and is
2248  * authoritative. ass and pict fields may contain approximations.
2249  */
2251 
2252  /**
2253  * Formatted text, the ass field must be set by the decoder and is
2254  * authoritative. pict and text fields may contain approximations.
2255  */
2257 };
2258 
2259 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
2260 
2261 typedef struct AVSubtitleRect {
2262  int x; ///< top left corner of pict, undefined when pict is not set
2263  int y; ///< top left corner of pict, undefined when pict is not set
2264  int w; ///< width of pict, undefined when pict is not set
2265  int h; ///< height of pict, undefined when pict is not set
2266  int nb_colors; ///< number of colors in pict, undefined when pict is not set
2267 
2268  /**
2269  * data+linesize for the bitmap of this subtitle.
2270  * Can be set for text/ass as well once they are rendered.
2271  */
2272  uint8_t *data[4];
2273  int linesize[4];
2274 
2276 
2277  char *text; ///< 0 terminated plain UTF-8 text
2278 
2279  /**
2280  * 0 terminated ASS/SSA compatible event line.
2281  * The presentation of this is unaffected by the other values in this
2282  * struct.
2283  */
2284  char *ass;
2285 
2286  int flags;
2287 } AVSubtitleRect;
2288 
2289 typedef struct AVSubtitle {
2290  uint16_t format; /* 0 = graphics */
2291  uint32_t start_display_time; /* relative to packet pts, in ms */
2292  uint32_t end_display_time; /* relative to packet pts, in ms */
2293  unsigned num_rects;
2295  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2296 } AVSubtitle;
2297 
2298 /**
2299  * Return the LIBAVCODEC_VERSION_INT constant.
2300  */
2301 unsigned avcodec_version(void);
2302 
2303 /**
2304  * Return the libavcodec build-time configuration.
2305  */
2306 const char *avcodec_configuration(void);
2307 
2308 /**
2309  * Return the libavcodec license.
2310  */
2311 const char *avcodec_license(void);
2312 
2313 /**
2314  * Allocate an AVCodecContext and set its fields to default values. The
2315  * resulting struct should be freed with avcodec_free_context().
2316  *
2317  * @param codec if non-NULL, allocate private data and initialize defaults
2318  * for the given codec. It is illegal to then call avcodec_open2()
2319  * with a different codec.
2320  * If NULL, then the codec-specific defaults won't be initialized,
2321  * which may result in suboptimal default settings (this is
2322  * important mainly for encoders, e.g. libx264).
2323  *
2324  * @return An AVCodecContext filled with default values or NULL on failure.
2325  */
2327 
2328 /**
2329  * Free the codec context and everything associated with it and write NULL to
2330  * the provided pointer.
2331  */
2332 void avcodec_free_context(AVCodecContext **avctx);
2333 
2334 /**
2335  * Get the AVClass for AVCodecContext. It can be used in combination with
2336  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2337  *
2338  * @see av_opt_find().
2339  */
2340 const AVClass *avcodec_get_class(void);
2341 
2342 #if FF_API_GET_FRAME_CLASS
2343 /**
2344  * @deprecated This function should not be used.
2345  */
2347 const AVClass *avcodec_get_frame_class(void);
2348 #endif
2349 
2350 /**
2351  * Get the AVClass for AVSubtitleRect. It can be used in combination with
2352  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2353  *
2354  * @see av_opt_find().
2355  */
2357 
2358 /**
2359  * Fill the parameters struct based on the values from the supplied codec
2360  * context. Any allocated fields in par are freed and replaced with duplicates
2361  * of the corresponding fields in codec.
2362  *
2363  * @return >= 0 on success, a negative AVERROR code on failure
2364  */
2366  const AVCodecContext *codec);
2367 
2368 /**
2369  * Fill the codec context based on the values from the supplied codec
2370  * parameters. Any allocated fields in codec that have a corresponding field in
2371  * par are freed and replaced with duplicates of the corresponding field in par.
2372  * Fields in codec that do not have a counterpart in par are not touched.
2373  *
2374  * @return >= 0 on success, a negative AVERROR code on failure.
2375  */
2377  const AVCodecParameters *par);
2378 
2379 /**
2380  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2381  * function the context has to be allocated with avcodec_alloc_context3().
2382  *
2383  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2384  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2385  * retrieving a codec.
2386  *
2387  * @warning This function is not thread safe!
2388  *
2389  * @note Always call this function before using decoding routines (such as
2390  * @ref avcodec_receive_frame()).
2391  *
2392  * @code
2393  * av_dict_set(&opts, "b", "2.5M", 0);
2394  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2395  * if (!codec)
2396  * exit(1);
2397  *
2398  * context = avcodec_alloc_context3(codec);
2399  *
2400  * if (avcodec_open2(context, codec, opts) < 0)
2401  * exit(1);
2402  * @endcode
2403  *
2404  * @param avctx The context to initialize.
2405  * @param codec The codec to open this context for. If a non-NULL codec has been
2406  * previously passed to avcodec_alloc_context3() or
2407  * for this context, then this parameter MUST be either NULL or
2408  * equal to the previously passed codec.
2409  * @param options A dictionary filled with AVCodecContext and codec-private options.
2410  * On return this object will be filled with options that were not found.
2411  *
2412  * @return zero on success, a negative value on error
2413  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2414  * av_dict_set(), av_opt_find().
2415  */
2416 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2417 
2418 /**
2419  * Close a given AVCodecContext and free all the data associated with it
2420  * (but not the AVCodecContext itself).
2421  *
2422  * Calling this function on an AVCodecContext that hasn't been opened will free
2423  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2424  * codec. Subsequent calls will do nothing.
2425  *
2426  * @note Do not use this function. Use avcodec_free_context() to destroy a
2427  * codec context (either open or closed). Opening and closing a codec context
2428  * multiple times is not supported anymore -- use multiple codec contexts
2429  * instead.
2430  */
2431 int avcodec_close(AVCodecContext *avctx);
2432 
2433 /**
2434  * Free all allocated data in the given subtitle struct.
2435  *
2436  * @param sub AVSubtitle to free.
2437  */
2439 
2440 /**
2441  * @}
2442  */
2443 
2444 /**
2445  * @addtogroup lavc_decoding
2446  * @{
2447  */
2448 
2449 /**
2450  * The default callback for AVCodecContext.get_buffer2(). It is made public so
2451  * it can be called by custom get_buffer2() implementations for decoders without
2452  * AV_CODEC_CAP_DR1 set.
2453  */
2455 
2456 /**
2457  * The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2458  * it can be called by custom get_encode_buffer() implementations for encoders without
2459  * AV_CODEC_CAP_DR1 set.
2460  */
2462 
2463 /**
2464  * Modify width and height values so that they will result in a memory
2465  * buffer that is acceptable for the codec if you do not use any horizontal
2466  * padding.
2467  *
2468  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2469  */
2471 
2472 /**
2473  * Modify width and height values so that they will result in a memory
2474  * buffer that is acceptable for the codec if you also ensure that all
2475  * line sizes are a multiple of the respective linesize_align[i].
2476  *
2477  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2478  */
2480  int linesize_align[AV_NUM_DATA_POINTERS]);
2481 
2482 /**
2483  * Converts AVChromaLocation to swscale x/y chroma position.
2484  *
2485  * The positions represent the chroma (0,0) position in a coordinates system
2486  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2487  *
2488  * @param xpos horizontal chroma sample position
2489  * @param ypos vertical chroma sample position
2490  */
2491 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
2492 
2493 /**
2494  * Converts swscale x/y chroma position to AVChromaLocation.
2495  *
2496  * The positions represent the chroma (0,0) position in a coordinates system
2497  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2498  *
2499  * @param xpos horizontal chroma sample position
2500  * @param ypos vertical chroma sample position
2501  */
2502 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
2503 
2504 /**
2505  * Decode a subtitle message.
2506  * Return a negative value on error, otherwise return the number of bytes used.
2507  * If no subtitle could be decompressed, got_sub_ptr is zero.
2508  * Otherwise, the subtitle is stored in *sub.
2509  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
2510  * simplicity, because the performance difference is expected to be negligible
2511  * and reusing a get_buffer written for video codecs would probably perform badly
2512  * due to a potentially very different allocation pattern.
2513  *
2514  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2515  * and output. This means that for some packets they will not immediately
2516  * produce decoded output and need to be flushed at the end of decoding to get
2517  * all the decoded data. Flushing is done by calling this function with packets
2518  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2519  * returning subtitles. It is safe to flush even those decoders that are not
2520  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
2521  *
2522  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2523  * before packets may be fed to the decoder.
2524  *
2525  * @param avctx the codec context
2526  * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
2527  * must be freed with avsubtitle_free if *got_sub_ptr is set.
2528  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
2529  * @param[in] avpkt The input AVPacket containing the input buffer.
2530  */
2532  int *got_sub_ptr,
2533  AVPacket *avpkt);
2534 
2535 /**
2536  * Supply raw packet data as input to a decoder.
2537  *
2538  * Internally, this call will copy relevant AVCodecContext fields, which can
2539  * influence decoding per-packet, and apply them when the packet is actually
2540  * decoded. (For example AVCodecContext.skip_frame, which might direct the
2541  * decoder to drop the frame contained by the packet sent with this function.)
2542  *
2543  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2544  * larger than the actual read bytes because some optimized bitstream
2545  * readers read 32 or 64 bits at once and could read over the end.
2546  *
2547  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2548  * before packets may be fed to the decoder.
2549  *
2550  * @param avctx codec context
2551  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
2552  * frame, or several complete audio frames.
2553  * Ownership of the packet remains with the caller, and the
2554  * decoder will not write to the packet. The decoder may create
2555  * a reference to the packet data (or copy it if the packet is
2556  * not reference-counted).
2557  * Unlike with older APIs, the packet is always fully consumed,
2558  * and if it contains multiple frames (e.g. some audio codecs),
2559  * will require you to call avcodec_receive_frame() multiple
2560  * times afterwards before you can send a new packet.
2561  * It can be NULL (or an AVPacket with data set to NULL and
2562  * size set to 0); in this case, it is considered a flush
2563  * packet, which signals the end of the stream. Sending the
2564  * first flush packet will return success. Subsequent ones are
2565  * unnecessary and will return AVERROR_EOF. If the decoder
2566  * still has frames buffered, it will return them after sending
2567  * a flush packet.
2568  *
2569  * @return 0 on success, otherwise negative error code:
2570  * AVERROR(EAGAIN): input is not accepted in the current state - user
2571  * must read output with avcodec_receive_frame() (once
2572  * all output is read, the packet should be resent, and
2573  * the call will not fail with EAGAIN).
2574  * AVERROR_EOF: the decoder has been flushed, and no new packets can
2575  * be sent to it (also returned if more than 1 flush
2576  * packet is sent)
2577  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
2578  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
2579  * other errors: legitimate decoding errors
2580  */
2581 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
2582 
2583 /**
2584  * Return decoded output data from a decoder.
2585  *
2586  * @param avctx codec context
2587  * @param frame This will be set to a reference-counted video or audio
2588  * frame (depending on the decoder type) allocated by the
2589  * decoder. Note that the function will always call
2590  * av_frame_unref(frame) before doing anything else.
2591  *
2592  * @return
2593  * 0: success, a frame was returned
2594  * AVERROR(EAGAIN): output is not available in this state - user must try
2595  * to send new input
2596  * AVERROR_EOF: the decoder has been fully flushed, and there will be
2597  * no more output frames
2598  * AVERROR(EINVAL): codec not opened, or it is an encoder
2599  * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
2600  * with respect to first decoded frame. Applicable
2601  * when flag AV_CODEC_FLAG_DROPCHANGED is set.
2602  * other negative values: legitimate decoding errors
2603  */
2605 
2606 /**
2607  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
2608  * to retrieve buffered output packets.
2609  *
2610  * @param avctx codec context
2611  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
2612  * Ownership of the frame remains with the caller, and the
2613  * encoder will not write to the frame. The encoder may create
2614  * a reference to the frame data (or copy it if the frame is
2615  * not reference-counted).
2616  * It can be NULL, in which case it is considered a flush
2617  * packet. This signals the end of the stream. If the encoder
2618  * still has packets buffered, it will return them after this
2619  * call. Once flushing mode has been entered, additional flush
2620  * packets are ignored, and sending frames will return
2621  * AVERROR_EOF.
2622  *
2623  * For audio:
2624  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
2625  * can have any number of samples.
2626  * If it is not set, frame->nb_samples must be equal to
2627  * avctx->frame_size for all frames except the last.
2628  * The final frame may be smaller than avctx->frame_size.
2629  * @return 0 on success, otherwise negative error code:
2630  * AVERROR(EAGAIN): input is not accepted in the current state - user
2631  * must read output with avcodec_receive_packet() (once
2632  * all output is read, the packet should be resent, and
2633  * the call will not fail with EAGAIN).
2634  * AVERROR_EOF: the encoder has been flushed, and no new frames can
2635  * be sent to it
2636  * AVERROR(EINVAL): codec not opened, it is a decoder, or requires flush
2637  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
2638  * other errors: legitimate encoding errors
2639  */
2640 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
2641 
2642 /**
2643  * Read encoded data from the encoder.
2644  *
2645  * @param avctx codec context
2646  * @param avpkt This will be set to a reference-counted packet allocated by the
2647  * encoder. Note that the function will always call
2648  * av_packet_unref(avpkt) before doing anything else.
2649  * @return 0 on success, otherwise negative error code:
2650  * AVERROR(EAGAIN): output is not available in the current state - user
2651  * must try to send input
2652  * AVERROR_EOF: the encoder has been fully flushed, and there will be
2653  * no more output packets
2654  * AVERROR(EINVAL): codec not opened, or it is a decoder
2655  * other errors: legitimate encoding errors
2656  */
2657 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
2658 
2659 /**
2660  * Create and return a AVHWFramesContext with values adequate for hardware
2661  * decoding. This is meant to get called from the get_format callback, and is
2662  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
2663  * This API is for decoding with certain hardware acceleration modes/APIs only.
2664  *
2665  * The returned AVHWFramesContext is not initialized. The caller must do this
2666  * with av_hwframe_ctx_init().
2667  *
2668  * Calling this function is not a requirement, but makes it simpler to avoid
2669  * codec or hardware API specific details when manually allocating frames.
2670  *
2671  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
2672  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
2673  * it unnecessary to call this function or having to care about
2674  * AVHWFramesContext initialization at all.
2675  *
2676  * There are a number of requirements for calling this function:
2677  *
2678  * - It must be called from get_format with the same avctx parameter that was
2679  * passed to get_format. Calling it outside of get_format is not allowed, and
2680  * can trigger undefined behavior.
2681  * - The function is not always supported (see description of return values).
2682  * Even if this function returns successfully, hwaccel initialization could
2683  * fail later. (The degree to which implementations check whether the stream
2684  * is actually supported varies. Some do this check only after the user's
2685  * get_format callback returns.)
2686  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
2687  * user decides to use a AVHWFramesContext prepared with this API function,
2688  * the user must return the same hw_pix_fmt from get_format.
2689  * - The device_ref passed to this function must support the given hw_pix_fmt.
2690  * - After calling this API function, it is the user's responsibility to
2691  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
2692  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
2693  * before returning from get_format (this is implied by the normal
2694  * AVCodecContext.hw_frames_ctx API rules).
2695  * - The AVHWFramesContext parameters may change every time time get_format is
2696  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
2697  * you are inherently required to go through this process again on every
2698  * get_format call.
2699  * - It is perfectly possible to call this function without actually using
2700  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
2701  * previously initialized AVHWFramesContext, and calling this API function
2702  * only to test whether the required frame parameters have changed.
2703  * - Fields that use dynamically allocated values of any kind must not be set
2704  * by the user unless setting them is explicitly allowed by the documentation.
2705  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
2706  * the new free callback must call the potentially set previous free callback.
2707  * This API call may set any dynamically allocated fields, including the free
2708  * callback.
2709  *
2710  * The function will set at least the following fields on AVHWFramesContext
2711  * (potentially more, depending on hwaccel API):
2712  *
2713  * - All fields set by av_hwframe_ctx_alloc().
2714  * - Set the format field to hw_pix_fmt.
2715  * - Set the sw_format field to the most suited and most versatile format. (An
2716  * implication is that this will prefer generic formats over opaque formats
2717  * with arbitrary restrictions, if possible.)
2718  * - Set the width/height fields to the coded frame size, rounded up to the
2719  * API-specific minimum alignment.
2720  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
2721  * field to the number of maximum reference surfaces possible with the codec,
2722  * plus 1 surface for the user to work (meaning the user can safely reference
2723  * at most 1 decoded surface at a time), plus additional buffering introduced
2724  * by frame threading. If the hwaccel does not require pre-allocation, the
2725  * field is left to 0, and the decoder will allocate new surfaces on demand
2726  * during decoding.
2727  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
2728  * hardware API.
2729  *
2730  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
2731  * with basic frame parameters set.
2732  *
2733  * The function is stateless, and does not change the AVCodecContext or the
2734  * device_ref AVHWDeviceContext.
2735  *
2736  * @param avctx The context which is currently calling get_format, and which
2737  * implicitly contains all state needed for filling the returned
2738  * AVHWFramesContext properly.
2739  * @param device_ref A reference to the AVHWDeviceContext describing the device
2740  * which will be used by the hardware decoder.
2741  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
2742  * @param out_frames_ref On success, set to a reference to an _uninitialized_
2743  * AVHWFramesContext, created from the given device_ref.
2744  * Fields will be set to values required for decoding.
2745  * Not changed if an error is returned.
2746  * @return zero on success, a negative value on error. The following error codes
2747  * have special semantics:
2748  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
2749  * is always manual, or it is a decoder which does not
2750  * support setting AVCodecContext.hw_frames_ctx at all,
2751  * or it is a software format.
2752  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
2753  * this configuration, or the device_ref is not supported
2754  * for the hwaccel referenced by hw_pix_fmt.
2755  */
2757  AVBufferRef *device_ref,
2759  AVBufferRef **out_frames_ref);
2760 
2761 
2762 
2763 /**
2764  * @defgroup lavc_parsing Frame parsing
2765  * @{
2766  */
2767 
2770  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
2771  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
2772  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
2773 };
2774 
2775 typedef struct AVCodecParserContext {
2776  void *priv_data;
2777  const struct AVCodecParser *parser;
2778  int64_t frame_offset; /* offset of the current frame */
2779  int64_t cur_offset; /* current offset
2780  (incremented by each av_parser_parse()) */
2781  int64_t next_frame_offset; /* offset of the next frame */
2782  /* video info */
2783  int pict_type; /* XXX: Put it back in AVCodecContext. */
2784  /**
2785  * This field is used for proper frame duration computation in lavf.
2786  * It signals, how much longer the frame duration of the current frame
2787  * is compared to normal frame duration.
2788  *
2789  * frame_duration = (1 + repeat_pict) * time_base
2790  *
2791  * It is used by codecs like H.264 to display telecined material.
2792  */
2793  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
2794  int64_t pts; /* pts of the current frame */
2795  int64_t dts; /* dts of the current frame */
2796 
2797  /* private data */
2798  int64_t last_pts;
2799  int64_t last_dts;
2801 
2802 #define AV_PARSER_PTS_NB 4
2807 
2808  int flags;
2809 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
2810 #define PARSER_FLAG_ONCE 0x0002
2811 /// Set if the parser has a valid file offset
2812 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
2813 #define PARSER_FLAG_USE_CODEC_TS 0x1000
2814 
2815  int64_t offset; ///< byte offset from starting packet start
2817 
2818  /**
2819  * Set by parser to 1 for key frames and 0 for non-key frames.
2820  * It is initialized to -1, so if the parser doesn't set this flag,
2821  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
2822  * will be used.
2823  */
2825 
2826  // Timestamp generation support:
2827  /**
2828  * Synchronization point for start of timestamp generation.
2829  *
2830  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
2831  * (default).
2832  *
2833  * For example, this corresponds to presence of H.264 buffering period
2834  * SEI message.
2835  */
2837 
2838  /**
2839  * Offset of the current timestamp against last timestamp sync point in
2840  * units of AVCodecContext.time_base.
2841  *
2842  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2843  * contain a valid timestamp offset.
2844  *
2845  * Note that the timestamp of sync point has usually a nonzero
2846  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
2847  * the next frame after timestamp sync point will be usually 1.
2848  *
2849  * For example, this corresponds to H.264 cpb_removal_delay.
2850  */
2852 
2853  /**
2854  * Presentation delay of current frame in units of AVCodecContext.time_base.
2855  *
2856  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2857  * contain valid non-negative timestamp delta (presentation time of a frame
2858  * must not lie in the past).
2859  *
2860  * This delay represents the difference between decoding and presentation
2861  * time of the frame.
2862  *
2863  * For example, this corresponds to H.264 dpb_output_delay.
2864  */
2866 
2867  /**
2868  * Position of the packet in file.
2869  *
2870  * Analogous to cur_frame_pts/dts
2871  */
2873 
2874  /**
2875  * Byte position of currently parsed frame in stream.
2876  */
2877  int64_t pos;
2878 
2879  /**
2880  * Previous frame byte position.
2881  */
2882  int64_t last_pos;
2883 
2884  /**
2885  * Duration of the current frame.
2886  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
2887  * For all other types, this is in units of AVCodecContext.time_base.
2888  */
2890 
2892 
2893  /**
2894  * Indicate whether a picture is coded as a frame, top field or bottom field.
2895  *
2896  * For example, H.264 field_pic_flag equal to 0 corresponds to
2897  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
2898  * equal to 1 and bottom_field_flag equal to 0 corresponds to
2899  * AV_PICTURE_STRUCTURE_TOP_FIELD.
2900  */
2902 
2903  /**
2904  * Picture number incremented in presentation or output order.
2905  * This field may be reinitialized at the first picture of a new sequence.
2906  *
2907  * For example, this corresponds to H.264 PicOrderCnt.
2908  */
2910 
2911  /**
2912  * Dimensions of the decoded video intended for presentation.
2913  */
2914  int width;
2915  int height;
2916 
2917  /**
2918  * Dimensions of the coded video.
2919  */
2922 
2923  /**
2924  * The format of the coded data, corresponds to enum AVPixelFormat for video
2925  * and for enum AVSampleFormat for audio.
2926  *
2927  * Note that a decoder can have considerable freedom in how exactly it
2928  * decodes the data, so the format reported here might be different from the
2929  * one returned by a decoder.
2930  */
2931  int format;
2933 
2934 typedef struct AVCodecParser {
2935  int codec_ids[7]; /* several codec IDs are permitted */
2938  /* This callback never returns an error, a negative value means that
2939  * the frame start was in a previous packet. */
2941  AVCodecContext *avctx,
2942  const uint8_t **poutbuf, int *poutbuf_size,
2943  const uint8_t *buf, int buf_size);
2945  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
2946 } AVCodecParser;
2947 
2948 /**
2949  * Iterate over all registered codec parsers.
2950  *
2951  * @param opaque a pointer where libavcodec will store the iteration state. Must
2952  * point to NULL to start the iteration.
2953  *
2954  * @return the next registered codec parser or NULL when the iteration is
2955  * finished
2956  */
2957 const AVCodecParser *av_parser_iterate(void **opaque);
2958 
2960 
2961 /**
2962  * Parse a packet.
2963  *
2964  * @param s parser context.
2965  * @param avctx codec context.
2966  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
2967  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
2968  * @param buf input buffer.
2969  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
2970  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
2971  To signal EOF, this should be 0 (so that the last frame
2972  can be output).
2973  * @param pts input presentation timestamp.
2974  * @param dts input decoding timestamp.
2975  * @param pos input byte position in stream.
2976  * @return the number of bytes of the input bitstream used.
2977  *
2978  * Example:
2979  * @code
2980  * while(in_len){
2981  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
2982  * in_data, in_len,
2983  * pts, dts, pos);
2984  * in_data += len;
2985  * in_len -= len;
2986  *
2987  * if(size)
2988  * decode_frame(data, size);
2989  * }
2990  * @endcode
2991  */
2993  AVCodecContext *avctx,
2994  uint8_t **poutbuf, int *poutbuf_size,
2995  const uint8_t *buf, int buf_size,
2996  int64_t pts, int64_t dts,
2997  int64_t pos);
2998 
3000 
3001 /**
3002  * @}
3003  * @}
3004  */
3005 
3006 /**
3007  * @addtogroup lavc_encoding
3008  * @{
3009  */
3010 
3011 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3012  const AVSubtitle *sub);
3013 
3014 
3015 /**
3016  * @}
3017  */
3018 
3019 /**
3020  * @defgroup lavc_misc Utility functions
3021  * @ingroup libavc
3022  *
3023  * Miscellaneous utility functions related to both encoding and decoding
3024  * (or neither).
3025  * @{
3026  */
3027 
3028 /**
3029  * @defgroup lavc_misc_pixfmt Pixel formats
3030  *
3031  * Functions for working with pixel formats.
3032  * @{
3033  */
3034 
3035 /**
3036  * Return a value representing the fourCC code associated to the
3037  * pixel format pix_fmt, or 0 if no associated fourCC code can be
3038  * found.
3039  */
3041 
3042 /**
3043  * Find the best pixel format to convert to given a certain source pixel
3044  * format. When converting from one pixel format to another, information loss
3045  * may occur. For example, when converting from RGB24 to GRAY, the color
3046  * information will be lost. Similarly, other losses occur when converting from
3047  * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
3048  * the given pixel formats should be used to suffer the least amount of loss.
3049  * The pixel formats from which it chooses one, are determined by the
3050  * pix_fmt_list parameter.
3051  *
3052  *
3053  * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
3054  * @param[in] src_pix_fmt source pixel format
3055  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
3056  * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
3057  * @return The best pixel format to convert to or -1 if none was found.
3058  */
3059 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
3060  enum AVPixelFormat src_pix_fmt,
3061  int has_alpha, int *loss_ptr);
3062 
3064 
3065 /**
3066  * @}
3067  */
3068 
3069 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
3070 
3071 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
3072 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
3073 //FIXME func typedef
3074 
3075 /**
3076  * Fill AVFrame audio data and linesize pointers.
3077  *
3078  * The buffer buf must be a preallocated buffer with a size big enough
3079  * to contain the specified samples amount. The filled AVFrame data
3080  * pointers will point to this buffer.
3081  *
3082  * AVFrame extended_data channel pointers are allocated if necessary for
3083  * planar audio.
3084  *
3085  * @param frame the AVFrame
3086  * frame->nb_samples must be set prior to calling the
3087  * function. This function fills in frame->data,
3088  * frame->extended_data, frame->linesize[0].
3089  * @param nb_channels channel count
3090  * @param sample_fmt sample format
3091  * @param buf buffer to use for frame data
3092  * @param buf_size size of buffer
3093  * @param align plane size sample alignment (0 = default)
3094  * @return >=0 on success, negative error code on failure
3095  * @todo return the size in bytes required to store the samples in
3096  * case of success, at the next libavutil bump
3097  */
3099  enum AVSampleFormat sample_fmt, const uint8_t *buf,
3100  int buf_size, int align);
3101 
3102 /**
3103  * Reset the internal codec state / flush internal buffers. Should be called
3104  * e.g. when seeking or when switching to a different stream.
3105  *
3106  * @note for decoders, this function just releases any references the decoder
3107  * might keep internally, but the caller's references remain valid.
3108  *
3109  * @note for encoders, this function will only do something if the encoder
3110  * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3111  * will drain any remaining packets, and can then be re-used for a different
3112  * stream (as opposed to sending a null frame which will leave the encoder
3113  * in a permanent EOF state after draining). This can be desirable if the
3114  * cost of tearing down and replacing the encoder instance is high.
3115  */
3117 
3118 /**
3119  * Return audio frame duration.
3120  *
3121  * @param avctx codec context
3122  * @param frame_bytes size of the frame, or 0 if unknown
3123  * @return frame duration, in samples, if known. 0 if not able to
3124  * determine.
3125  */
3126 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
3127 
3128 /* memory */
3129 
3130 /**
3131  * Same behaviour av_fast_malloc but the buffer has additional
3132  * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
3133  *
3134  * In addition the whole buffer will initially and after resizes
3135  * be 0-initialized so that no uninitialized data will ever appear.
3136  */
3137 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
3138 
3139 /**
3140  * Same behaviour av_fast_padded_malloc except that buffer will always
3141  * be 0-initialized after call.
3142  */
3143 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
3144 
3145 /**
3146  * @return a positive value if s is open (i.e. avcodec_open2() was called on it
3147  * with no corresponding avcodec_close()), 0 otherwise.
3148  */
3150 
3151 /**
3152  * @}
3153  */
3154 
3155 #endif /* AVCODEC_AVCODEC_H */
AVSubtitle
Definition: avcodec.h:2289
avcodec_close
int avcodec_close(AVCodecContext *avctx)
Close a given AVCodecContext and free all the data associated with it (but not the AVCodecContext its...
Definition: avcodec.c:444
func
int(* func)(AVBPrint *dst, const char *in, const char *arg)
Definition: jacosubdec.c:68
avcodec_encode_subtitle
int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size, const AVSubtitle *sub)
Definition: encode.c:143
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1012
AVCodecContext::hwaccel
const struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:1359
AVCodec
AVCodec.
Definition: codec.h:202
AVCodecContext::hwaccel_context
void * hwaccel_context
Hardware accelerator context.
Definition: avcodec.h:1370
hw_pix_fmt
static enum AVPixelFormat hw_pix_fmt
Definition: hw_decode.c:46
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVCodecParserContext::pts
int64_t pts
Definition: avcodec.h:2794
AVCodecContext::log_level_offset
int log_level_offset
Definition: avcodec.h:389
AVCodecContext::keyint_min
int keyint_min
minimum GOP size
Definition: avcodec.h:925
avcodec_receive_packet
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:389
AVCodecContext::workaround_bugs
int workaround_bugs
Work around bugs in encoders which sometimes cannot be detected automatically.
Definition: avcodec.h:1251
AVSubtitle::rects
AVSubtitleRect ** rects
Definition: avcodec.h:2294
AVCodecContext::get_format
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Callback to negotiate the pixel format.
Definition: avcodec.h:647
AVCodecParserContext::dts_sync_point
int dts_sync_point
Synchronization point for start of timestamp generation.
Definition: avcodec.h:2836
AVCodecContext::audio_service_type
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:1057
AVCodecContext::channel_layout
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1043
AVCodecContext::colorspace
enum AVColorSpace colorspace
YUV colorspace type.
Definition: avcodec.h:960
AVColorTransferCharacteristic
AVColorTransferCharacteristic
Color Transfer Characteristic.
Definition: pixfmt.h:476
AVCodecContext::av_class
const AVClass * av_class
information on struct for av_log
Definition: avcodec.h:388
AVCodecParserContext::pict_type
int pict_type
Definition: avcodec.h:2783
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:992
AVCodecContext::rc_min_rate
int64_t rc_min_rate
minimum bitrate
Definition: avcodec.h:1201
AVCodecParserContext::output_picture_number
int output_picture_number
Picture number incremented in presentation or output order.
Definition: avcodec.h:2909
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
sub
static float sub(float src0, float src1)
Definition: dnn_backend_native_layer_mathbinary.c:31
AVHWAccel::type
enum AVMediaType type
Type of codec implemented by the hardware accelerator.
Definition: avcodec.h:2052
AV_PICTURE_STRUCTURE_UNKNOWN
@ AV_PICTURE_STRUCTURE_UNKNOWN
Definition: avcodec.h:2769
AVHWAccel::caps_internal
int caps_internal
Internal hwaccel capabilities.
Definition: avcodec.h:2188
avcodec_parameters_from_context
int avcodec_parameters_from_context(AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: codec_par.c:90
AVCodecParserContext::duration
int duration
Duration of the current frame.
Definition: avcodec.h:2889
AVCodecContext::err_recognition
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1324
avcodec_string
void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
Definition: avcodec.c:519
rational.h
AVCodecContext::coded_side_data
AVPacketSideData * coded_side_data
Additional data associated with the entire coded stream.
Definition: avcodec.h:1833
AVSubtitleRect
Definition: avcodec.h:2261
AVSubtitle::num_rects
unsigned num_rects
Definition: avcodec.h:2293
av_parser_iterate
const AVCodecParser * av_parser_iterate(void **opaque)
Iterate over all registered codec parsers.
Definition: parsers.c:79
AVCodecContext::intra_matrix
uint16_t * intra_matrix
custom intra quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:868
AVCodecContext::mv0_threshold
int mv0_threshold
Note: Value depends upon the compare function used for fullpel ME.
Definition: avcodec.h:939
AVCodecContext::lumi_masking
float lumi_masking
luminance masking (0-> disabled)
Definition: avcodec.h:702
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
AVCodecContext::color_trc
enum AVColorTransferCharacteristic color_trc
Color Transfer Characteristic.
Definition: avcodec.h:953
AVPacketSideData
Definition: packet.h:314
AVCodecParserContext::pts_dts_delta
int pts_dts_delta
Presentation delay of current frame in units of AVCodecContext.time_base.
Definition: avcodec.h:2865
AVCodecContext::slice_offset
int * slice_offset
slice offsets in the frame in bytes
Definition: avcodec.h:744
avcodec_decode_subtitle2
int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub, int *got_sub_ptr, AVPacket *avpkt)
Decode a subtitle message.
Definition: decode.c:806
AVCodecContext::field_order
enum AVFieldOrder field_order
Field order.
Definition: avcodec.h:989
AVHWAccel::capabilities
int capabilities
Hardware accelerated codec capabilities.
Definition: avcodec.h:2072
AVCodecContext::b_quant_offset
float b_quant_offset
qscale offset between IP and B-frames
Definition: avcodec.h:671
AVCodecParserContext::height
int height
Definition: avcodec.h:2915
avcodec_align_dimensions
void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height)
Modify width and height values so that they will result in a memory buffer that is acceptable for the...
Definition: utils.c:337
RcOverride::qscale
int qscale
Definition: avcodec.h:193
AVHWAccel::init
int(* init)(AVCodecContext *avctx)
Initialize the hwaccel private data.
Definition: avcodec.h:2169
AVCodecContext::subtitle_header
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:1683
version.h
AVSubtitleRect::linesize
int linesize[4]
Definition: avcodec.h:2273
AVCodecParserContext::cur_frame_start_index
int cur_frame_start_index
Definition: avcodec.h:2803
AVCodecContext::me_pre_cmp
int me_pre_cmp
motion estimation prepass comparison function
Definition: avcodec.h:816
MpegEncContext::avctx
struct AVCodecContext * avctx
Definition: mpegvideo.h:88
AVDictionary
Definition: dict.c:30
AVColorPrimaries
AVColorPrimaries
Chromaticity coordinates of the source primaries.
Definition: pixfmt.h:451
avcodec_default_get_format
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: decode.c:875
avcodec_find_best_pix_fmt_of_list
enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list, enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr)
Find the best pixel format to convert to given a certain source pixel format.
Definition: imgconvert.c:31
AVCodecContext::mb_decision
int mb_decision
macroblock decision mode
Definition: avcodec.h:856
avcodec_is_open
int avcodec_is_open(AVCodecContext *s)
Definition: avcodec.c:713
AVCodecContext::qmax
int qmax
maximum quantizer
Definition: avcodec.h:1165
AVCodecContext::request_channel_layout
uint64_t request_channel_layout
Request decoder to use this channel layout if it can (0 for default)
Definition: avcodec.h:1050
AVCodecParserContext::coded_width
int coded_width
Dimensions of the coded video.
Definition: avcodec.h:2920
AVCodecContext::delay
int delay
Codec delay.
Definition: avcodec.h:539
AVCodecContext::me_subpel_quality
int me_subpel_quality
subpel ME quality
Definition: avcodec.h:830
AVCodecContext::mb_cmp
int mb_cmp
macroblock comparison function (not supported yet)
Definition: avcodec.h:772
AVCodecContext::slice_count
int slice_count
slice count
Definition: avcodec.h:737
AVPictureStructure
AVPictureStructure
Definition: avcodec.h:2768
avcodec_pix_fmt_to_codec_tag
unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt)
Return a value representing the fourCC code associated to the pixel format pix_fmt,...
Definition: raw.c:305
SUBTITLE_ASS
@ SUBTITLE_ASS
Formatted text, the ass field must be set by the decoder and is authoritative.
Definition: avcodec.h:2256
AVCodecParserContext::parser
const struct AVCodecParser * parser
Definition: avcodec.h:2777
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:1710
AVCodecContext::skip_top
int skip_top
Number of macroblock rows at the top which are skipped.
Definition: avcodec.h:891
avcodec_enum_to_chroma_pos
int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos)
Converts AVChromaLocation to swscale x/y chroma position.
Definition: utils.c:352
AVCodecParserContext::offset
int64_t offset
byte offset from starting packet start
Definition: avcodec.h:2815
AVHWAccel
Definition: avcodec.h:2039
AVCodecParserContext::key_frame
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:2824
AVCodecContext::skip_idct
enum AVDiscard skip_idct
Skip IDCT/dequantization for selected frames.
Definition: avcodec.h:1666
AVCodecContext::i_quant_factor
float i_quant_factor
qscale factor between P- and I-frames If > 0 then the last P-frame quantizer will be used (q = lastp_...
Definition: avcodec.h:688
AVCodecContext::nsse_weight
int nsse_weight
noise vs.
Definition: avcodec.h:1518
AVCodecContext::codec
const struct AVCodec * codec
Definition: avcodec.h:392
AVCodecContext::skip_frame
enum AVDiscard skip_frame
Skip decoding for selected frames.
Definition: avcodec.h:1673
AVCodecContext::thread_count
int thread_count
thread count is used to decide how many independent tasks should be passed to execute()
Definition: avcodec.h:1440
samplefmt.h
AVSubtitleRect::x
int x
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2262
AVCodecContext::initial_padding
int initial_padding
Audio only.
Definition: avcodec.h:1701
AVCodecContext::refs
int refs
number of reference frames
Definition: avcodec.h:932
avcodec_default_execute2
int avcodec_default_execute2(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2, int, int), void *arg, int *ret, int count)
AVCodecContext::flags
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:463
AVCodecContext::bit_rate_tolerance
int bit_rate_tolerance
number of bits the bitstream is allowed to diverge from the reference.
Definition: avcodec.h:441
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
AVCodecContext::dct_algo
int dct_algo
DCT algorithm, see FF_DCT_* below.
Definition: avcodec.h:1384
av_parser_init
AVCodecParserContext * av_parser_init(int codec_id)
Definition: parser.c:34
pts
static int64_t pts
Definition: transcode_aac.c:653
AVCodecContext::coded_height
int coded_height
Definition: avcodec.h:571
AVCodecContext::max_samples
int64_t max_samples
The number of samples per frame to maximally accept.
Definition: avcodec.h:1974
codec.h
AVCodecParserContext::dts
int64_t dts
Definition: avcodec.h:2795
AVSubtitleRect::ass
char * ass
0 terminated ASS/SSA compatible event line.
Definition: avcodec.h:2284
AVHWAccel::priv_data_size
int priv_data_size
Size of the private data to allocate in AVCodecInternal.hwaccel_priv_data.
Definition: avcodec.h:2183
avsubtitle_free
void avsubtitle_free(AVSubtitle *sub)
Free all allocated data in the given subtitle struct.
Definition: avcodec.c:425
AVCodecContext::get_buffer2
int(* get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags)
This callback is called at the beginning of each frame to get data buffer(s) for it.
Definition: avcodec.h:1147
AV_PICTURE_STRUCTURE_FRAME
@ AV_PICTURE_STRUCTURE_FRAME
Definition: avcodec.h:2772
RcOverride::quality_factor
float quality_factor
Definition: avcodec.h:194
AVCodecContext::color_primaries
enum AVColorPrimaries color_primaries
Chromaticity coordinates of the source primaries.
Definition: avcodec.h:946
AVCodecParserContext::cur_frame_end
int64_t cur_frame_end[AV_PARSER_PTS_NB]
Definition: avcodec.h:2816
pkt
AVPacket * pkt
Definition: movenc.c:59
AVCodecContext::pts_correction_num_faulty_pts
int64_t pts_correction_num_faulty_pts
Current statistics for PTS correction.
Definition: avcodec.h:1738
AVCodecContext::rc_initial_buffer_occupancy
int rc_initial_buffer_occupancy
Number of bits which should be loaded into the rc buffer before decoding starts.
Definition: avcodec.h:1222
codec_id.h
AVHWAccel::alloc_frame
int(* alloc_frame)(AVCodecContext *avctx, AVFrame *frame)
Allocate a custom buffer.
Definition: avcodec.h:2085
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:485
AVCodecContext::has_b_frames
int has_b_frames
Size of the frame reordering buffer in the decoder.
Definition: avcodec.h:679
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:141
width
#define width
AVCodecDescriptor
This struct describes the properties of a single codec described by an AVCodecID.
Definition: codec_desc.h:38
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVCodecContext::stats_in
char * stats_in
pass2 encoding statistics input buffer Concatenated stuff from stats_out of pass1 should be placed he...
Definition: avcodec.h:1244
AVCodecContext::global_quality
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:449
AVCodecParserContext::fetch_timestamp
int fetch_timestamp
Definition: avcodec.h:2800
AVHWAccel::uninit
int(* uninit)(AVCodecContext *avctx)
Uninitialize the hwaccel private data.
Definition: avcodec.h:2177
RcOverride
Definition: avcodec.h:190
AVCodecParserContext::last_pts
int64_t last_pts
Definition: avcodec.h:2798
AVSubtitleRect::y
int y
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2263
AVCodecContext::ticks_per_frame
int ticks_per_frame
For some codecs, the time base is closer to the field rate than the frame rate.
Definition: avcodec.h:515
AVCodecContext::error_concealment
int error_concealment
error concealment flags
Definition: avcodec.h:1292
avcodec_receive_frame
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:643
AVSubtitleType
AVSubtitleType
Definition: avcodec.h:2241
AVCodecContext::thread_type
int thread_type
Which multithreading methods to use.
Definition: avcodec.h:1450
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1425
avcodec_fill_audio_frame
int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels, enum AVSampleFormat sample_fmt, const uint8_t *buf, int buf_size, int align)
Fill AVFrame audio data and linesize pointers.
Definition: utils.c:375
RcOverride::start_frame
int start_frame
Definition: avcodec.h:191
AVCodecParserContext::format
int format
The format of the coded data, corresponds to enum AVPixelFormat for video and for enum AVSampleFormat...
Definition: avcodec.h:2931
AVSubtitle::pts
int64_t pts
Same as packet pts, in AV_TIME_BASE.
Definition: avcodec.h:2295
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demuxing_decoding.c:41
avcodec_align_dimensions2
void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height, int linesize_align[AV_NUM_DATA_POINTERS])
Modify width and height values so that they will result in a memory buffer that is acceptable for the...
Definition: utils.c:136
AVCodecContext::max_pixels
int64_t max_pixels
The number of pixels per image to maximally accept.
Definition: avcodec.h:1886
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:369
AVHWAccel::decode_params
int(* decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size)
Callback for parameter data (SPS/PPS/VPS etc).
Definition: avcodec.h:2115
AVCodecContext::rc_max_rate
int64_t rc_max_rate
maximum bitrate
Definition: avcodec.h:1194
AVCodecContext::error
uint64_t error[AV_NUM_DATA_POINTERS]
error
Definition: avcodec.h:1377
AVSubtitleRect::text
char * text
0 terminated plain UTF-8 text
Definition: avcodec.h:2277
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:393
AVCodecContext::p_masking
float p_masking
p block masking (0-> disabled)
Definition: avcodec.h:723
arg
const char * arg
Definition: jacosubdec.c:67
AVCodecParserContext::dts_ref_dts_delta
int dts_ref_dts_delta
Offset of the current timestamp against last timestamp sync point in units of AVCodecContext....
Definition: avcodec.h:2851
AVCodecParserContext::repeat_pict
int repeat_pict
This field is used for proper frame duration computation in lavf.
Definition: avcodec.h:2793
AV_PICTURE_STRUCTURE_BOTTOM_FIELD
@ AV_PICTURE_STRUCTURE_BOTTOM_FIELD
Definition: avcodec.h:2771
AVCodecContext::rc_buffer_size
int rc_buffer_size
decoder bitstream buffer size
Definition: avcodec.h:1179
AVCodecContext::sub_charenc
char * sub_charenc
DTS of the last frame.
Definition: avcodec.h:1748
AVSubtitleRect::w
int w
width of pict, undefined when pict is not set
Definition: avcodec.h:2264
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
avcodec_get_class
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:174
AVCodecContext::apply_cropping
int apply_cropping
Video decoding only.
Definition: avcodec.h:1944
AVCodecContext::color_range
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:967
AVCodecContext::slice_flags
int slice_flags
slice flags
Definition: avcodec.h:846
AVCodecParser::parser_close
void(* parser_close)(AVCodecParserContext *s)
Definition: avcodec.h:2944
avcodec_free_context
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
Definition: options.c:156
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVCodecContext::nb_coded_side_data
int nb_coded_side_data
Definition: avcodec.h:1834
AVCodecContext::qblur
float qblur
amount of qscale smoothing over time (0.0-1.0)
Definition: avcodec.h:1151
AV_PICTURE_STRUCTURE_TOP_FIELD
@ AV_PICTURE_STRUCTURE_TOP_FIELD
Definition: avcodec.h:2770
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:433
AVCodecParser::split
int(* split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
Definition: avcodec.h:2945
AVHWAccel::end_frame
int(* end_frame)(AVCodecContext *avctx)
Called at the end of each frame or field picture.
Definition: avcodec.h:2140
AVCodecContext::subtitle_header_size
int subtitle_header_size
Definition: avcodec.h:1684
AVSubtitleRect::data
uint8_t * data[4]
data+linesize for the bitmap of this subtitle.
Definition: avcodec.h:2272
src
#define src
Definition: vp8dsp.c:255
AVCodecContext::trailing_padding
int trailing_padding
Audio only.
Definition: avcodec.h:1878
AVCodecContext::ildct_cmp
int ildct_cmp
interlaced DCT comparison function
Definition: avcodec.h:778
avcodec_license
const char * avcodec_license(void)
Return the libavcodec license.
Definition: avcodec.c:61
AVCodecContext::thread_safe_callbacks
attribute_deprecated int thread_safe_callbacks
Set by the client if its custom get_buffer() callback can be called synchronously from another thread...
Definition: avcodec.h:1479
AVCodecContext::rc_min_vbv_overflow_use
float rc_min_vbv_overflow_use
Ratecontrol attempt to use, at least, times the amount needed to prevent a vbv overflow.
Definition: avcodec.h:1215
avcodec_open2
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:137
AVCodecParserContext::flags
int flags
Definition: avcodec.h:2808
avcodec_version
unsigned avcodec_version(void)
Return the LIBAVCODEC_VERSION_INT constant.
Definition: avcodec.c:46
AVCodecContext::me_cmp
int me_cmp
motion estimation comparison function
Definition: avcodec.h:760
AVCodecParserContext::picture_structure
enum AVPictureStructure picture_structure
Indicate whether a picture is coded as a frame, top field or bottom field.
Definition: avcodec.h:2901
AVCodecContext::trellis
int trellis
trellis RD quantization
Definition: avcodec.h:1229
AVCodecContext::level
int level
level
Definition: avcodec.h:1651
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVAudioServiceType
AVAudioServiceType
Definition: defs.h:57
avcodec_get_subtitle_rect_class
const AVClass * avcodec_get_subtitle_rect_class(void)
Get the AVClass for AVSubtitleRect.
Definition: options.c:228
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:47
AVCodecContext::temporal_cplx_masking
float temporal_cplx_masking
temporary complexity masking (0-> disabled)
Definition: avcodec.h:709
AVCodecContext::qcompress
float qcompress
amount of qscale change between easy & hard scenes (0.0-1.0)
Definition: avcodec.h:1150
AVCodecContext::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avcodec.h:506
AVCodecContext::lowres
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:1432
options
const OptionDef options[]
AVCodecContext::stats_out
char * stats_out
pass1 encoding statistics output buffer
Definition: avcodec.h:1236
AVCodecContext::rc_override
RcOverride * rc_override
Definition: avcodec.h:1187
AVCodecContext::flags2
int flags2
AV_CODEC_FLAG2_*.
Definition: avcodec.h:470
AVMediaType
AVMediaType
Definition: avutil.h:199
AVCodecParserContext::frame_offset
int64_t frame_offset
Definition: avcodec.h:2778
AVCodecContext::gop_size
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:578
AVCodecParser::codec_ids
int codec_ids[7]
Definition: avcodec.h:2935
AVCodecContext::extra_hw_frames
int extra_hw_frames
Definition: avcodec.h:1958
AVCodecParserContext::next_frame_offset
int64_t next_frame_offset
Definition: avcodec.h:2781
AVCodecParserContext::cur_frame_offset
int64_t cur_frame_offset[AV_PARSER_PTS_NB]
Definition: avcodec.h:2804
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1000
AVCodecContext::pkt_timebase
AVRational pkt_timebase
Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
Definition: avcodec.h:1724
size
int size
Definition: twinvq_data.h:10344
AVCodecParserContext::width
int width
Dimensions of the decoded video intended for presentation.
Definition: avcodec.h:2914
AV_NUM_DATA_POINTERS
#define AV_NUM_DATA_POINTERS
Definition: frame.h:304
avcodec_get_frame_class
const attribute_deprecated AVClass * avcodec_get_frame_class(void)
Definition: options.c:202
AVCodecContext::me_range
int me_range
maximum motion estimation search range in subpel units If 0 then no limit.
Definition: avcodec.h:839
AVCodecParser::parser_parse
int(* parser_parse)(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)
Definition: avcodec.h:2940
AVCodecContext::skip_alpha
int skip_alpha
Skip processing alpha if supported by codec.
Definition: avcodec.h:1774
AVCodecContext::chroma_intra_matrix
uint16_t * chroma_intra_matrix
custom intra quantization matrix
Definition: avcodec.h:1799
AVCodecContext::skip_bottom
int skip_bottom
Number of macroblock rows at the bottom which are skipped.
Definition: avcodec.h:898
AVCodecContext::last_predictor_count
int last_predictor_count
amount of previous MV predictors (2a+1 x 2a+1 square)
Definition: avcodec.h:809
AVSubtitle::end_display_time
uint32_t end_display_time
Definition: avcodec.h:2292
frame.h
AVSubtitleRect::type
enum AVSubtitleType type
Definition: avcodec.h:2275
SUBTITLE_TEXT
@ SUBTITLE_TEXT
Plain text, the text field must be set by the decoder and is authoritative.
Definition: avcodec.h:2250
buffer.h
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
SUBTITLE_NONE
@ SUBTITLE_NONE
Definition: avcodec.h:2242
encode
static void encode(AVCodecContext *ctx, AVFrame *frame, AVPacket *pkt, FILE *output)
Definition: encode_audio.c:95
AVCodecContext::me_sub_cmp
int me_sub_cmp
subpixel motion estimation comparison function
Definition: avcodec.h:766
AVCodecContext::pts_correction_num_faulty_dts
int64_t pts_correction_num_faulty_dts
Number of incorrect PTS values so far.
Definition: avcodec.h:1739
height
#define height
AVCodecContext::pts_correction_last_pts
int64_t pts_correction_last_pts
Number of incorrect DTS values so far.
Definition: avcodec.h:1740
avcodec_default_execute
int avcodec_default_execute(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
Definition: avcodec.c:67
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
AVCodecContext::request_sample_fmt
enum AVSampleFormat request_sample_fmt
desired sample format
Definition: avcodec.h:1065
attributes.h
AVCodecInternal
Definition: internal.h:123
AVCodecContext::skip_loop_filter
enum AVDiscard skip_loop_filter
Skip loop filtering for selected frames.
Definition: avcodec.h:1659
SUBTITLE_BITMAP
@ SUBTITLE_BITMAP
A bitmap, pict will be set.
Definition: avcodec.h:2244
AVCodecContext::b_quant_factor
float b_quant_factor
qscale factor between IP and B-frames If > 0 then the last P-frame quantizer will be used (q= lastp_q...
Definition: avcodec.h:664
AVCodecParserContext::cur_frame_pts
int64_t cur_frame_pts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2805
AVCodecContext::channels
int channels
number of audio channels
Definition: avcodec.h:993
AVChromaLocation
AVChromaLocation
Location of chroma samples.
Definition: pixfmt.h:598
AVCodecParserContext::cur_frame_pos
int64_t cur_frame_pos[AV_PARSER_PTS_NB]
Position of the packet in file.
Definition: avcodec.h:2872
AVHWAccel::name
const char * name
Name of the hardware accelerated codec.
Definition: avcodec.h:2045
AVSubtitleRect::flags
int flags
Definition: avcodec.h:2286
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1418
avcodec_default_get_buffer2
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags)
The default callback for AVCodecContext.get_buffer2().
Definition: decode.c:1453
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:580
AVCodecParserContext::pos
int64_t pos
Byte position of currently parsed frame in stream.
Definition: avcodec.h:2877
AVSubtitle::format
uint16_t format
Definition: avcodec.h:2290
log.h
RcOverride::end_frame
int end_frame
Definition: avcodec.h:192
AVCodecContext::properties
unsigned properties
Properties of the stream that gets decoded.
Definition: avcodec.h:1822
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:484
AVSubtitleRect::nb_colors
int nb_colors
number of colors in pict, undefined when pict is not set
Definition: avcodec.h:2266
AVHWAccel::decode_slice
int(* decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size)
Callback for each slice.
Definition: avcodec.h:2129
packet.h
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: codec_par.c:147
AVCodecContext::intra_dc_precision
int intra_dc_precision
precision of the intra DC coefficient - 8
Definition: avcodec.h:884
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:505
AVCodecContext::cutoff
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1036
AVCodecContext::hwaccel_flags
int hwaccel_flags
Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated decoding (if active).
Definition: avcodec.h:1917
AVCodecParserContext::cur_offset
int64_t cur_offset
Definition: avcodec.h:2779
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
av_fast_padded_malloc
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_malloc but the buffer has additional AV_INPUT_BUFFER_PADDING_SIZE at the end w...
Definition: utils.c:50
AVCodecParser::parser_init
int(* parser_init)(AVCodecParserContext *s)
Definition: avcodec.h:2937
AVCodecContext::pts_correction_last_dts
int64_t pts_correction_last_dts
PTS of the last frame.
Definition: avcodec.h:1741
AVCodecContext::dia_size
int dia_size
ME diamond size & shape.
Definition: avcodec.h:802
AVCodecContext::dump_separator
uint8_t * dump_separator
dump format separator.
Definition: avcodec.h:1807
AVCodecContext::mb_lmin
int mb_lmin
minimum MB Lagrange multiplier
Definition: avcodec.h:905
av_get_audio_frame_duration
int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
Return audio frame duration.
Definition: utils.c:817
AVCodecContext::idct_algo
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:1397
AVCodecContext::hw_device_ctx
AVBufferRef * hw_device_ctx
A reference to the AVHWDeviceContext describing the device which will be used by a hardware encoder/d...
Definition: avcodec.h:1908
AVCodecContext::chroma_sample_location
enum AVChromaLocation chroma_sample_location
This defines the location of chroma samples.
Definition: avcodec.h:974
AVCodecContext::height
int height
Definition: avcodec.h:556
avcodec_send_frame
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Supply a raw video or audio frame to the encoder.
Definition: encode.c:358
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:593
AVCodecContext::hw_frames_ctx
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames.
Definition: avcodec.h:1858
AVCodecParserContext
Definition: avcodec.h:2775
AVCodecContext::sub_charenc_mode
int sub_charenc_mode
Subtitles character encoding mode.
Definition: avcodec.h:1756
AVHWAccel::decode_mb
void(* decode_mb)(struct MpegEncContext *s)
Called for every Macroblock in a slice.
Definition: avcodec.h:2160
avcodec_get_hw_frames_parameters
int avcodec_get_hw_frames_parameters(AVCodecContext *avctx, AVBufferRef *device_ref, enum AVPixelFormat hw_pix_fmt, AVBufferRef **out_frames_ref)
Create and return a AVHWFramesContext with values adequate for hardware decoding.
Definition: decode.c:989
ret
ret
Definition: filter_design.txt:187
AVSubtitleRect::h
int h
height of pict, undefined when pict is not set
Definition: avcodec.h:2265
AVCodecContext::block_align
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs.
Definition: avcodec.h:1029
pixfmt.h
avcodec_flush_buffers
void avcodec_flush_buffers(AVCodecContext *avctx)
Reset the internal codec state / flush internal buffers.
Definition: avcodec.c:379
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AVCodecContext::sub_text_format
attribute_deprecated int sub_text_format
Definition: avcodec.h:1865
AVCodecParserContext::coded_height
int coded_height
Definition: avcodec.h:2921
AVCodecContext::strict_std_compliance
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1280
AVCodecContext::opaque
void * opaque
Private data of the user, can be used to carry app specific stuff.
Definition: avcodec.h:425
pos
unsigned int pos
Definition: spdifenc.c:412
AVCodecParser::priv_data_size
int priv_data_size
Definition: avcodec.h:2936
dict.h
AVCodecContext::draw_horiz_band
void(* draw_horiz_band)(struct AVCodecContext *s, const AVFrame *src, int offset[AV_NUM_DATA_POINTERS], int y, int type, int height)
If non NULL, 'draw_horiz_band' is called by the libavcodec decoder to draw a horizontal band.
Definition: avcodec.h:618
AVCodecContext::max_qdiff
int max_qdiff
maximum quantizer difference between frames
Definition: avcodec.h:1172
AVCodecContext::dark_masking
float dark_masking
darkness masking (0-> disabled)
Definition: avcodec.h:730
AVCodecContext
main external API structure.
Definition: avcodec.h:383
AVCodecContext::active_thread_type
int active_thread_type
Which multithreading methods are in use by the codec.
Definition: avcodec.h:1459
AVCodecContext::codec_descriptor
const AVCodecDescriptor * codec_descriptor
AVCodecDescriptor.
Definition: avcodec.h:1731
c2
static const uint64_t c2
Definition: murmur3.c:52
AVCodecParserContext::field_order
enum AVFieldOrder field_order
Definition: avcodec.h:2891
AVCodecContext::execute
int(* execute)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size)
The codec may call this to execute several independent things.
Definition: avcodec.h:1491
AVCodecContext::qmin
int qmin
minimum quantizer
Definition: avcodec.h:1158
AVHWAccel::frame_priv_data_size
int frame_priv_data_size
Size of per-frame hardware accelerator private data.
Definition: avcodec.h:2149
AVCodecContext::bidir_refine
int bidir_refine
Definition: avcodec.h:918
AVCodecContext::profile
int profile
profile
Definition: avcodec.h:1525
defs.h
av_fast_padded_mallocz
void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_padded_malloc except that buffer will always be 0-initialized after call.
Definition: utils.c:63
AVCodecContext::get_encode_buffer
int(* get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags)
This callback is called at the beginning of each packet to get a data buffer for it.
Definition: avcodec.h:2026
AVCodecContext::spatial_cplx_masking
float spatial_cplx_masking
spatial complexity masking (0-> disabled)
Definition: avcodec.h:716
AVCodecContext::i_quant_offset
float i_quant_offset
qscale offset between P and I-frames
Definition: avcodec.h:695
AVCodecContext::discard_damaged_percentage
int discard_damaged_percentage
The percentage of damaged samples to discard a frame.
Definition: avcodec.h:1966
AVCodecContext::mb_lmax
int mb_lmax
maximum MB Lagrange multiplier
Definition: avcodec.h:912
AVCodecContext::export_side_data
int export_side_data
Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of metadata exported in frame,...
Definition: avcodec.h:1984
avcodec_chroma_pos_to_enum
enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos)
Converts swscale x/y chroma position to AVChromaLocation.
Definition: utils.c:364
AVCodecContext::pre_dia_size
int pre_dia_size
ME prepass diamond size & shape.
Definition: avcodec.h:823
AVCodecContext::debug
int debug
debug
Definition: avcodec.h:1302
AVHWAccel::start_frame
int(* start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size)
Called at the beginning of each frame or field picture.
Definition: avcodec.h:2101
AVCodecContext::coded_width
int coded_width
Bitstream width / height, may be different from width/height e.g.
Definition: avcodec.h:571
AVCodecContext::codec_type
enum AVMediaType codec_type
Definition: avcodec.h:391
AVCodecContext::seek_preroll
int seek_preroll
Number of samples to skip after a discontinuity.
Definition: avcodec.h:1781
av_parser_parse2
int av_parser_parse2(AVCodecParserContext *s, AVCodecContext *avctx, uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size, int64_t pts, int64_t dts, int64_t pos)
Parse a packet.
Definition: parser.c:117
avutil.h
AVCodecContext::max_b_frames
int max_b_frames
maximum number of B-frames between non-B-frames Note: The output will be delayed by max_b_frames+1 re...
Definition: avcodec.h:655
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
AVCodecContext::frame_number
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:1023
AVCodecContext::rc_max_available_vbv_use
float rc_max_available_vbv_use
Ratecontrol attempt to use, at maximum, of what can be used without an underflow.
Definition: avcodec.h:1208
AVCodecContext::codec_tag
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:408
codec_par.h
AVFieldOrder
AVFieldOrder
Definition: codec_par.h:36
AV_PARSER_PTS_NB
#define AV_PARSER_PTS_NB
Definition: avcodec.h:2802
AVCodecContext::slices
int slices
Number of slices.
Definition: avcodec.h:983
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:410
avcodec_default_get_encode_buffer
int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags)
The default callback for AVCodecContext.get_encode_buffer().
Definition: encode.c:56
AVCodecParserContext::last_pos
int64_t last_pos
Previous frame byte position.
Definition: avcodec.h:2882
AVCodecContext::inter_matrix
uint16_t * inter_matrix
custom inter quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:877
AVHWAccel::frame_params
int(* frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx)
Fill the given hw_frames context with current codec parameters.
Definition: avcodec.h:2198
AVCodecParser
Definition: avcodec.h:2934
AVCodecContext::rc_override_count
int rc_override_count
ratecontrol override, see RcOverride
Definition: avcodec.h:1186
AVCodecContext::reordered_opaque
int64_t reordered_opaque
opaque 64-bit number (generally a PTS) that will be reordered and output in AVFrame....
Definition: avcodec.h:1352
avcodec_configuration
const char * avcodec_configuration(void)
Return the libavcodec build-time configuration.
Definition: avcodec.c:56
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:556
AVCodecContext::debug_mv
attribute_deprecated int debug_mv
Definition: avcodec.h:1788
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParserContext::priv_data
void * priv_data
Definition: avcodec.h:2776
AVCodecContext::sw_pix_fmt
enum AVPixelFormat sw_pix_fmt
Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1717
AVCodecParserContext::cur_frame_dts
int64_t cur_frame_dts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2806
AVCodecContext::codec_whitelist
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avcodec.h:1815
AVDiscard
AVDiscard
Definition: defs.h:45
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:544
AVCodecParserContext::last_dts
int64_t last_dts
Definition: avcodec.h:2799
codec_desc.h
int
int
Definition: ffmpeg_filter.c:156
MpegEncContext
MpegEncContext.
Definition: mpegvideo.h:71
AVCodecContext::execute2
int(* execute2)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count)
The codec may call this to execute several independent things.
Definition: avcodec.h:1511
AVHWAccel::pix_fmt
enum AVPixelFormat pix_fmt
Supported pixel format.
Definition: avcodec.h:2066
AVCodecContext::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown) That is the width of a pixel divided by the height of the pixel.
Definition: avcodec.h:753
AVSubtitle::start_display_time
uint32_t start_display_time
Definition: avcodec.h:2291
AVCodecContext::compression_level
int compression_level
Definition: avcodec.h:455
av_parser_close
void av_parser_close(AVCodecParserContext *s)
Definition: parser.c:191
nb_channels
int nb_channels
Definition: channel_layout.c:81
AVHWAccel::id
enum AVCodecID id
Codec implemented by the hardware accelerator.
Definition: avcodec.h:2059