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_major.h"
47 #ifndef HAVE_AV_CONFIG_H
48 /* When included as part of the ffmpeg build, only include the major version
49  * to avoid unnecessary rebuilds. When included externally, keep including
50  * the full version information. */
51 #include "version.h"
52 #endif
53 
54 /**
55  * @defgroup libavc libavcodec
56  * Encoding/Decoding Library
57  *
58  * @{
59  *
60  * @defgroup lavc_decoding Decoding
61  * @{
62  * @}
63  *
64  * @defgroup lavc_encoding Encoding
65  * @{
66  * @}
67  *
68  * @defgroup lavc_codec Codecs
69  * @{
70  * @defgroup lavc_codec_native Native Codecs
71  * @{
72  * @}
73  * @defgroup lavc_codec_wrappers External library wrappers
74  * @{
75  * @}
76  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
77  * @{
78  * @}
79  * @}
80  * @defgroup lavc_internal Internal
81  * @{
82  * @}
83  * @}
84  */
85 
86 /**
87  * @ingroup libavc
88  * @defgroup lavc_encdec send/receive encoding and decoding API overview
89  * @{
90  *
91  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
92  * avcodec_receive_packet() functions provide an encode/decode API, which
93  * decouples input and output.
94  *
95  * The API is very similar for encoding/decoding and audio/video, and works as
96  * follows:
97  * - Set up and open the AVCodecContext as usual.
98  * - Send valid input:
99  * - For decoding, call avcodec_send_packet() to give the decoder raw
100  * compressed data in an AVPacket.
101  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
102  * containing uncompressed audio or video.
103  *
104  * In both cases, it is recommended that AVPackets and AVFrames are
105  * refcounted, or libavcodec might have to copy the input data. (libavformat
106  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
107  * refcounted AVFrames.)
108  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
109  * functions and process their output:
110  * - For decoding, call avcodec_receive_frame(). On success, it will return
111  * an AVFrame containing uncompressed audio or video data.
112  * - For encoding, call avcodec_receive_packet(). On success, it will return
113  * an AVPacket with a compressed frame.
114  *
115  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
116  * AVERROR(EAGAIN) return value means that new input data is required to
117  * return new output. In this case, continue with sending input. For each
118  * input frame/packet, the codec will typically return 1 output frame/packet,
119  * but it can also be 0 or more than 1.
120  *
121  * At the beginning of decoding or encoding, the codec might accept multiple
122  * input frames/packets without returning a frame, until its internal buffers
123  * are filled. This situation is handled transparently if you follow the steps
124  * outlined above.
125  *
126  * In theory, sending input can result in EAGAIN - this should happen only if
127  * not all output was received. You can use this to structure alternative decode
128  * or encode loops other than the one suggested above. For example, you could
129  * try sending new input on each iteration, and try to receive output if that
130  * returns EAGAIN.
131  *
132  * End of stream situations. These require "flushing" (aka draining) the codec,
133  * as the codec might buffer multiple frames or packets internally for
134  * performance or out of necessity (consider B-frames).
135  * This is handled as follows:
136  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
137  * or avcodec_send_frame() (encoding) functions. This will enter draining
138  * mode.
139  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
140  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
141  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
142  * - Before decoding can be resumed again, the codec has to be reset with
143  * avcodec_flush_buffers().
144  *
145  * Using the API as outlined above is highly recommended. But it is also
146  * possible to call functions outside of this rigid schema. For example, you can
147  * call avcodec_send_packet() repeatedly without calling
148  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
149  * until the codec's internal buffer has been filled up (which is typically of
150  * size 1 per output frame, after initial input), and then reject input with
151  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
152  * read at least some output.
153  *
154  * Not all codecs will follow a rigid and predictable dataflow; the only
155  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
156  * one end implies that a receive/send call on the other end will succeed, or
157  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
158  * permit unlimited buffering of input or output.
159  *
160  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
161  * would be an invalid state, which could put the codec user into an endless
162  * loop. The API has no concept of time either: it cannot happen that trying to
163  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
164  * later accepts the packet (with no other receive/flush API calls involved).
165  * The API is a strict state machine, and the passage of time is not supposed
166  * to influence it. Some timing-dependent behavior might still be deemed
167  * acceptable in certain cases. But it must never result in both send/receive
168  * returning EAGAIN at the same time at any point. It must also absolutely be
169  * avoided that the current state is "unstable" and can "flip-flop" between
170  * the send/receive APIs allowing progress. For example, it's not allowed that
171  * the codec randomly decides that it actually wants to consume a packet now
172  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
173  * avcodec_send_packet() call.
174  * @}
175  */
176 
177 /**
178  * @defgroup lavc_core Core functions/structures.
179  * @ingroup libavc
180  *
181  * Basic definitions, functions for querying libavcodec capabilities,
182  * allocating core structures, etc.
183  * @{
184  */
185 
186 /**
187  * @ingroup lavc_encoding
188  * minimum encoding buffer size
189  * Used to avoid some checks during header writing.
190  */
191 #define AV_INPUT_BUFFER_MIN_SIZE 16384
192 
193 /**
194  * @ingroup lavc_encoding
195  */
196 typedef struct RcOverride{
199  int qscale; // If this is 0 then quality_factor will be used instead.
201 } RcOverride;
202 
203 /* encoding support
204  These flags can be passed in AVCodecContext.flags before initialization.
205  Note: Not everything is supported yet.
206 */
207 
208 /**
209  * Allow decoders to produce frames with data planes that are not aligned
210  * to CPU requirements (e.g. due to cropping).
211  */
212 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
213 /**
214  * Use fixed qscale.
215  */
216 #define AV_CODEC_FLAG_QSCALE (1 << 1)
217 /**
218  * 4 MV per MB allowed / advanced prediction for H.263.
219  */
220 #define AV_CODEC_FLAG_4MV (1 << 2)
221 /**
222  * Output even those frames that might be corrupted.
223  */
224 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
225 /**
226  * Use qpel MC.
227  */
228 #define AV_CODEC_FLAG_QPEL (1 << 4)
229 /**
230  * Don't output frames whose parameters differ from first
231  * decoded frame in stream.
232  */
233 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
234 /**
235  * Request the encoder to output reconstructed frames, i.e.\ frames that would
236  * be produced by decoding the encoded bistream. These frames may be retrieved
237  * by calling avcodec_receive_frame() immediately after a successful call to
238  * avcodec_receive_packet().
239  *
240  * Should only be used with encoders flagged with the
241  * @ref AV_CODEC_CAP_ENCODER_RECON_FRAME capability.
242  */
243 #define AV_CODEC_FLAG_RECON_FRAME (1 << 6)
244 /**
245  * Request the encoder to propagate each frame's AVFrame.opaque and
246  * AVFrame.opaque_ref values to its corresponding output AVPacket.
247  *
248  * May only be set on encoders that have the
249  * @ref AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability flag.
250  *
251  * @note
252  * While in typical cases one input frame produces exactly one output packet
253  * (perhaps after a delay), in general the mapping of frames to packets is
254  * M-to-N, so
255  * - Any number of input frames may be associated with any given output packet.
256  * This includes zero - e.g. some encoders may output packets that carry only
257  * metadata about the whole stream.
258  * - A given input frame may be associated with any number of output packets.
259  * Again this includes zero - e.g. some encoders may drop frames under certain
260  * conditions.
261  * .
262  * This implies that when using this flag, the caller must NOT assume that
263  * - a given input frame's opaques will necessarily appear on some output packet;
264  * - every output packet will have some non-NULL opaque value.
265  * .
266  * When an output packet contains multiple frames, the opaque values will be
267  * taken from the first of those.
268  */
269 #define AV_CODEC_FLAG_COPY_OPAQUE (1 << 7)
270 /**
271  * Signal to the encoder that the values of AVFrame.duration are valid and
272  * should be used (typically for transferring them to output packets).
273  *
274  * If this flag is not set, frame durations are ignored.
275  */
276 #define AV_CODEC_FLAG_FRAME_DURATION (1 << 8)
277 /**
278  * Use internal 2pass ratecontrol in first pass mode.
279  */
280 #define AV_CODEC_FLAG_PASS1 (1 << 9)
281 /**
282  * Use internal 2pass ratecontrol in second pass mode.
283  */
284 #define AV_CODEC_FLAG_PASS2 (1 << 10)
285 /**
286  * loop filter.
287  */
288 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
289 /**
290  * Only decode/encode grayscale.
291  */
292 #define AV_CODEC_FLAG_GRAY (1 << 13)
293 /**
294  * error[?] variables will be set during encoding.
295  */
296 #define AV_CODEC_FLAG_PSNR (1 << 15)
297 #if FF_API_FLAG_TRUNCATED
298 /**
299  * Input bitstream might be truncated at a random location
300  * instead of only at frame boundaries.
301  *
302  * @deprecated use codec parsers for packetizing input
303  */
304 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
305 #endif
306 /**
307  * Use interlaced DCT.
308  */
309 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
310 /**
311  * Force low delay.
312  */
313 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
314 /**
315  * Place global headers in extradata instead of every keyframe.
316  */
317 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
318 /**
319  * Use only bitexact stuff (except (I)DCT).
320  */
321 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
322 /* Fx : Flag for H.263+ extra options */
323 /**
324  * H.263 advanced intra coding / MPEG-4 AC prediction
325  */
326 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
327 /**
328  * interlaced motion estimation
329  */
330 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
331 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
332 
333 /**
334  * Allow non spec compliant speedup tricks.
335  */
336 #define AV_CODEC_FLAG2_FAST (1 << 0)
337 /**
338  * Skip bitstream encoding.
339  */
340 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
341 /**
342  * Place global headers at every keyframe instead of in extradata.
343  */
344 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
345 
346 /**
347  * timecode is in drop frame format. DEPRECATED!!!!
348  */
349 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
350 
351 /**
352  * Input bitstream might be truncated at a packet boundaries
353  * instead of only at frame boundaries.
354  */
355 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
356 /**
357  * Discard cropping information from SPS.
358  */
359 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
360 
361 /**
362  * Show all frames before the first keyframe
363  */
364 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
365 /**
366  * Export motion vectors through frame side data
367  */
368 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
369 /**
370  * Do not skip samples and export skip information as frame side data
371  */
372 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
373 /**
374  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
375  */
376 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
377 /**
378  * Generate/parse ICC profiles on encode/decode, as appropriate for the type of
379  * file. No effect on codecs which cannot contain embedded ICC profiles, or
380  * when compiled without support for lcms2.
381  */
382 #define AV_CODEC_FLAG2_ICC_PROFILES (1U << 31)
383 
384 /* Exported side data.
385  These flags can be passed in AVCodecContext.export_side_data before initialization.
386 */
387 /**
388  * Export motion vectors through frame side data
389  */
390 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
391 /**
392  * Export encoder Producer Reference Time through packet side data
393  */
394 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
395 /**
396  * Decoding only.
397  * Export the AVVideoEncParams structure through frame side data.
398  */
399 #define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
400 /**
401  * Decoding only.
402  * Do not apply film grain, export it instead.
403  */
404 #define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
405 
406 /**
407  * The decoder will keep a reference to the frame and may reuse it later.
408  */
409 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
410 
411 /**
412  * The encoder will keep a reference to the packet and may reuse it later.
413  */
414 #define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
415 
416 struct AVCodecInternal;
417 
418 /**
419  * main external API structure.
420  * New fields can be added to the end with minor version bumps.
421  * Removal, reordering and changes to existing fields require a major
422  * version bump.
423  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
424  * applications.
425  * The name string for AVOptions options matches the associated command line
426  * parameter name and can be found in libavcodec/options_table.h
427  * The AVOption/command line parameter names differ in some cases from the C
428  * structure field names for historic reasons or brevity.
429  * sizeof(AVCodecContext) must not be used outside libav*.
430  */
431 typedef struct AVCodecContext {
432  /**
433  * information on struct for av_log
434  * - set by avcodec_alloc_context3
435  */
438 
439  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
440  const struct AVCodec *codec;
441  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
442 
443  /**
444  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
445  * This is used to work around some encoder bugs.
446  * A demuxer should set this to what is stored in the field used to identify the codec.
447  * If there are multiple such fields in a container then the demuxer should choose the one
448  * which maximizes the information about the used codec.
449  * If the codec tag field in a container is larger than 32 bits then the demuxer should
450  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
451  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
452  * first.
453  * - encoding: Set by user, if not then the default based on codec_id will be used.
454  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
455  */
456  unsigned int codec_tag;
457 
458  void *priv_data;
459 
460  /**
461  * Private context used for internal data.
462  *
463  * Unlike priv_data, this is not codec-specific. It is used in general
464  * libavcodec functions.
465  */
466  struct AVCodecInternal *internal;
467 
468  /**
469  * Private data of the user, can be used to carry app specific stuff.
470  * - encoding: Set by user.
471  * - decoding: Set by user.
472  */
473  void *opaque;
474 
475  /**
476  * the average bitrate
477  * - encoding: Set by user; unused for constant quantizer encoding.
478  * - decoding: Set by user, may be overwritten by libavcodec
479  * if this info is available in the stream
480  */
481  int64_t bit_rate;
482 
483  /**
484  * number of bits the bitstream is allowed to diverge from the reference.
485  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
486  * - encoding: Set by user; unused for constant quantizer encoding.
487  * - decoding: unused
488  */
490 
491  /**
492  * Global quality for codecs which cannot change it per frame.
493  * This should be proportional to MPEG-1/2/4 qscale.
494  * - encoding: Set by user.
495  * - decoding: unused
496  */
498 
499  /**
500  * - encoding: Set by user.
501  * - decoding: unused
502  */
504 #define FF_COMPRESSION_DEFAULT -1
505 
506  /**
507  * AV_CODEC_FLAG_*.
508  * - encoding: Set by user.
509  * - decoding: Set by user.
510  */
511  int flags;
512 
513  /**
514  * AV_CODEC_FLAG2_*
515  * - encoding: Set by user.
516  * - decoding: Set by user.
517  */
518  int flags2;
519 
520  /**
521  * some codecs need / can use extradata like Huffman tables.
522  * MJPEG: Huffman tables
523  * rv10: additional flags
524  * MPEG-4: global headers (they can be in the bitstream or here)
525  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
526  * than extradata_size to avoid problems if it is read with the bitstream reader.
527  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
528  * Must be allocated with the av_malloc() family of functions.
529  * - encoding: Set/allocated/freed by libavcodec.
530  * - decoding: Set/allocated/freed by user.
531  */
532  uint8_t *extradata;
534 
535  /**
536  * This is the fundamental unit of time (in seconds) in terms
537  * of which frame timestamps are represented. For fixed-fps content,
538  * timebase should be 1/framerate and timestamp increments should be
539  * identically 1.
540  * This often, but not always is the inverse of the frame rate or field rate
541  * for video. 1/time_base is not the average frame rate if the frame rate is not
542  * constant.
543  *
544  * Like containers, elementary streams also can store timestamps, 1/time_base
545  * is the unit in which these timestamps are specified.
546  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
547  * vop_time_increment_resolution and fixed_vop_rate
548  * (fixed_vop_rate == 0 implies that it is different from the framerate)
549  *
550  * - encoding: MUST be set by user.
551  * - decoding: the use of this field for decoding is deprecated.
552  * Use framerate instead.
553  */
555 
556  /**
557  * For some codecs, the time base is closer to the field rate than the frame rate.
558  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
559  * if no telecine is used ...
560  *
561  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
562  */
564 
565  /**
566  * Codec delay.
567  *
568  * Encoding: Number of frames delay there will be from the encoder input to
569  * the decoder output. (we assume the decoder matches the spec)
570  * Decoding: Number of frames delay in addition to what a standard decoder
571  * as specified in the spec would produce.
572  *
573  * Video:
574  * Number of frames the decoded output will be delayed relative to the
575  * encoded input.
576  *
577  * Audio:
578  * For encoding, this field is unused (see initial_padding).
579  *
580  * For decoding, this is the number of samples the decoder needs to
581  * output before the decoder's output is valid. When seeking, you should
582  * start decoding this many samples prior to your desired seek point.
583  *
584  * - encoding: Set by libavcodec.
585  * - decoding: Set by libavcodec.
586  */
587  int delay;
588 
589 
590  /* video only */
591  /**
592  * picture width / height.
593  *
594  * @note Those fields may not match the values of the last
595  * AVFrame output by avcodec_receive_frame() due frame
596  * reordering.
597  *
598  * - encoding: MUST be set by user.
599  * - decoding: May be set by the user before opening the decoder if known e.g.
600  * from the container. Some decoders will require the dimensions
601  * to be set by the caller. During decoding, the decoder may
602  * overwrite those values as required while parsing the data.
603  */
604  int width, height;
605 
606  /**
607  * Bitstream width / height, may be different from width/height e.g. when
608  * the decoded frame is cropped before being output or lowres is enabled.
609  *
610  * @note Those field may not match the value of the last
611  * AVFrame output by avcodec_receive_frame() due frame
612  * reordering.
613  *
614  * - encoding: unused
615  * - decoding: May be set by the user before opening the decoder if known
616  * e.g. from the container. During decoding, the decoder may
617  * overwrite those values as required while parsing the data.
618  */
620 
621  /**
622  * the number of pictures in a group of pictures, or 0 for intra_only
623  * - encoding: Set by user.
624  * - decoding: unused
625  */
626  int gop_size;
627 
628  /**
629  * Pixel format, see AV_PIX_FMT_xxx.
630  * May be set by the demuxer if known from headers.
631  * May be overridden by the decoder if it knows better.
632  *
633  * @note This field may not match the value of the last
634  * AVFrame output by avcodec_receive_frame() due frame
635  * reordering.
636  *
637  * - encoding: Set by user.
638  * - decoding: Set by user if known, overridden by libavcodec while
639  * parsing the data.
640  */
642 
643  /**
644  * If non NULL, 'draw_horiz_band' is called by the libavcodec
645  * decoder to draw a horizontal band. It improves cache usage. Not
646  * all codecs can do that. You must check the codec capabilities
647  * beforehand.
648  * When multithreading is used, it may be called from multiple threads
649  * at the same time; threads might draw different parts of the same AVFrame,
650  * or multiple AVFrames, and there is no guarantee that slices will be drawn
651  * in order.
652  * The function is also used by hardware acceleration APIs.
653  * It is called at least once during frame decoding to pass
654  * the data needed for hardware render.
655  * In that mode instead of pixel data, AVFrame points to
656  * a structure specific to the acceleration API. The application
657  * reads the structure and can change some fields to indicate progress
658  * or mark state.
659  * - encoding: unused
660  * - decoding: Set by user.
661  * @param height the height of the slice
662  * @param y the y position of the slice
663  * @param type 1->top field, 2->bottom field, 3->frame
664  * @param offset offset into the AVFrame.data from which the slice should be read
665  */
667  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
668  int y, int type, int height);
669 
670  /**
671  * Callback to negotiate the pixel format. Decoding only, may be set by the
672  * caller before avcodec_open2().
673  *
674  * Called by some decoders to select the pixel format that will be used for
675  * the output frames. This is mainly used to set up hardware acceleration,
676  * then the provided format list contains the corresponding hwaccel pixel
677  * formats alongside the "software" one. The software pixel format may also
678  * be retrieved from \ref sw_pix_fmt.
679  *
680  * This callback will be called when the coded frame properties (such as
681  * resolution, pixel format, etc.) change and more than one output format is
682  * supported for those new properties. If a hardware pixel format is chosen
683  * and initialization for it fails, the callback may be called again
684  * immediately.
685  *
686  * This callback may be called from different threads if the decoder is
687  * multi-threaded, but not from more than one thread simultaneously.
688  *
689  * @param fmt list of formats which may be used in the current
690  * configuration, terminated by AV_PIX_FMT_NONE.
691  * @warning Behavior is undefined if the callback returns a value other
692  * than one of the formats in fmt or AV_PIX_FMT_NONE.
693  * @return the chosen format or AV_PIX_FMT_NONE
694  */
695  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
696 
697  /**
698  * maximum number of B-frames between non-B-frames
699  * Note: The output will be delayed by max_b_frames+1 relative to the input.
700  * - encoding: Set by user.
701  * - decoding: unused
702  */
704 
705  /**
706  * qscale factor between IP and B-frames
707  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
708  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
709  * - encoding: Set by user.
710  * - decoding: unused
711  */
713 
714  /**
715  * qscale offset between IP and B-frames
716  * - encoding: Set by user.
717  * - decoding: unused
718  */
720 
721  /**
722  * Size of the frame reordering buffer in the decoder.
723  * For MPEG-2 it is 1 IPB or 0 low delay IP.
724  * - encoding: Set by libavcodec.
725  * - decoding: Set by libavcodec.
726  */
728 
729  /**
730  * qscale factor between P- and I-frames
731  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
732  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
733  * - encoding: Set by user.
734  * - decoding: unused
735  */
737 
738  /**
739  * qscale offset between P and I-frames
740  * - encoding: Set by user.
741  * - decoding: unused
742  */
744 
745  /**
746  * luminance masking (0-> disabled)
747  * - encoding: Set by user.
748  * - decoding: unused
749  */
751 
752  /**
753  * temporary complexity masking (0-> disabled)
754  * - encoding: Set by user.
755  * - decoding: unused
756  */
758 
759  /**
760  * spatial complexity masking (0-> disabled)
761  * - encoding: Set by user.
762  * - decoding: unused
763  */
765 
766  /**
767  * p block masking (0-> disabled)
768  * - encoding: Set by user.
769  * - decoding: unused
770  */
771  float p_masking;
772 
773  /**
774  * darkness masking (0-> disabled)
775  * - encoding: Set by user.
776  * - decoding: unused
777  */
779 
780  /**
781  * slice count
782  * - encoding: Set by libavcodec.
783  * - decoding: Set by user (or 0).
784  */
786 
787  /**
788  * slice offsets in the frame in bytes
789  * - encoding: Set/allocated by libavcodec.
790  * - decoding: Set/allocated by user (or NULL).
791  */
793 
794  /**
795  * sample aspect ratio (0 if unknown)
796  * That is the width of a pixel divided by the height of the pixel.
797  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
798  * - encoding: Set by user.
799  * - decoding: Set by libavcodec.
800  */
802 
803  /**
804  * motion estimation comparison function
805  * - encoding: Set by user.
806  * - decoding: unused
807  */
808  int me_cmp;
809  /**
810  * subpixel motion estimation comparison function
811  * - encoding: Set by user.
812  * - decoding: unused
813  */
815  /**
816  * macroblock comparison function (not supported yet)
817  * - encoding: Set by user.
818  * - decoding: unused
819  */
820  int mb_cmp;
821  /**
822  * interlaced DCT comparison function
823  * - encoding: Set by user.
824  * - decoding: unused
825  */
827 #define FF_CMP_SAD 0
828 #define FF_CMP_SSE 1
829 #define FF_CMP_SATD 2
830 #define FF_CMP_DCT 3
831 #define FF_CMP_PSNR 4
832 #define FF_CMP_BIT 5
833 #define FF_CMP_RD 6
834 #define FF_CMP_ZERO 7
835 #define FF_CMP_VSAD 8
836 #define FF_CMP_VSSE 9
837 #define FF_CMP_NSSE 10
838 #define FF_CMP_W53 11
839 #define FF_CMP_W97 12
840 #define FF_CMP_DCTMAX 13
841 #define FF_CMP_DCT264 14
842 #define FF_CMP_MEDIAN_SAD 15
843 #define FF_CMP_CHROMA 256
844 
845  /**
846  * ME diamond size & shape
847  * - encoding: Set by user.
848  * - decoding: unused
849  */
850  int dia_size;
851 
852  /**
853  * amount of previous MV predictors (2a+1 x 2a+1 square)
854  * - encoding: Set by user.
855  * - decoding: unused
856  */
858 
859  /**
860  * motion estimation prepass comparison function
861  * - encoding: Set by user.
862  * - decoding: unused
863  */
865 
866  /**
867  * ME prepass diamond size & shape
868  * - encoding: Set by user.
869  * - decoding: unused
870  */
872 
873  /**
874  * subpel ME quality
875  * - encoding: Set by user.
876  * - decoding: unused
877  */
879 
880  /**
881  * maximum motion estimation search range in subpel units
882  * If 0 then no limit.
883  *
884  * - encoding: Set by user.
885  * - decoding: unused
886  */
887  int me_range;
888 
889  /**
890  * slice flags
891  * - encoding: unused
892  * - decoding: Set by user.
893  */
895 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
896 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
897 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
898 
899  /**
900  * macroblock decision mode
901  * - encoding: Set by user.
902  * - decoding: unused
903  */
905 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
906 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
907 #define FF_MB_DECISION_RD 2 ///< rate distortion
908 
909  /**
910  * custom intra quantization matrix
911  * Must be allocated with the av_malloc() family of functions, and will be freed in
912  * avcodec_free_context().
913  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
914  * - decoding: Set/allocated/freed by libavcodec.
915  */
916  uint16_t *intra_matrix;
917 
918  /**
919  * custom inter quantization matrix
920  * Must be allocated with the av_malloc() family of functions, and will be freed in
921  * avcodec_free_context().
922  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
923  * - decoding: Set/allocated/freed by libavcodec.
924  */
925  uint16_t *inter_matrix;
926 
927  /**
928  * precision of the intra DC coefficient - 8
929  * - encoding: Set by user.
930  * - decoding: Set by libavcodec
931  */
933 
934  /**
935  * Number of macroblock rows at the top which are skipped.
936  * - encoding: unused
937  * - decoding: Set by user.
938  */
939  int skip_top;
940 
941  /**
942  * Number of macroblock rows at the bottom which are skipped.
943  * - encoding: unused
944  * - decoding: Set by user.
945  */
947 
948  /**
949  * minimum MB Lagrange multiplier
950  * - encoding: Set by user.
951  * - decoding: unused
952  */
953  int mb_lmin;
954 
955  /**
956  * maximum MB Lagrange multiplier
957  * - encoding: Set by user.
958  * - decoding: unused
959  */
960  int mb_lmax;
961 
962  /**
963  * - encoding: Set by user.
964  * - decoding: unused
965  */
967 
968  /**
969  * minimum GOP size
970  * - encoding: Set by user.
971  * - decoding: unused
972  */
974 
975  /**
976  * number of reference frames
977  * - encoding: Set by user.
978  * - decoding: Set by lavc.
979  */
980  int refs;
981 
982  /**
983  * Note: Value depends upon the compare function used for fullpel ME.
984  * - encoding: Set by user.
985  * - decoding: unused
986  */
988 
989  /**
990  * Chromaticity coordinates of the source primaries.
991  * - encoding: Set by user
992  * - decoding: Set by libavcodec
993  */
995 
996  /**
997  * Color Transfer Characteristic.
998  * - encoding: Set by user
999  * - decoding: Set by libavcodec
1000  */
1002 
1003  /**
1004  * YUV colorspace type.
1005  * - encoding: Set by user
1006  * - decoding: Set by libavcodec
1007  */
1009 
1010  /**
1011  * MPEG vs JPEG YUV range.
1012  * - encoding: Set by user
1013  * - decoding: Set by libavcodec
1014  */
1016 
1017  /**
1018  * This defines the location of chroma samples.
1019  * - encoding: Set by user
1020  * - decoding: Set by libavcodec
1021  */
1023 
1024  /**
1025  * Number of slices.
1026  * Indicates number of picture subdivisions. Used for parallelized
1027  * decoding.
1028  * - encoding: Set by user
1029  * - decoding: unused
1030  */
1031  int slices;
1032 
1033  /** Field order
1034  * - encoding: set by libavcodec
1035  * - decoding: Set by user.
1036  */
1038 
1039  /* audio only */
1040  int sample_rate; ///< samples per second
1041 
1042 #if FF_API_OLD_CHANNEL_LAYOUT
1043  /**
1044  * number of audio channels
1045  * @deprecated use ch_layout.nb_channels
1046  */
1048  int channels;
1049 #endif
1050 
1051  /**
1052  * audio sample format
1053  * - encoding: Set by user.
1054  * - decoding: Set by libavcodec.
1055  */
1056  enum AVSampleFormat sample_fmt; ///< sample format
1057 
1058  /* The following data should not be initialized. */
1059  /**
1060  * Number of samples per channel in an audio frame.
1061  *
1062  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1063  * except the last must contain exactly frame_size samples per channel.
1064  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1065  * frame size is not restricted.
1066  * - decoding: may be set by some decoders to indicate constant frame size
1067  */
1069 
1070  /**
1071  * Frame counter, set by libavcodec.
1072  *
1073  * - decoding: total number of frames returned from the decoder so far.
1074  * - encoding: total number of frames passed to the encoder so far.
1075  *
1076  * @note the counter is not incremented if encoding/decoding resulted in
1077  * an error.
1078  */
1080 
1081  /**
1082  * number of bytes per packet if constant and known or 0
1083  * Used by some WAV based audio codecs.
1084  */
1086 
1087  /**
1088  * Audio cutoff bandwidth (0 means "automatic")
1089  * - encoding: Set by user.
1090  * - decoding: unused
1091  */
1092  int cutoff;
1093 
1094 #if FF_API_OLD_CHANNEL_LAYOUT
1095  /**
1096  * Audio channel layout.
1097  * - encoding: set by user.
1098  * - decoding: set by user, may be overwritten by libavcodec.
1099  * @deprecated use ch_layout
1100  */
1102  uint64_t channel_layout;
1103 
1104  /**
1105  * Request decoder to use this channel layout if it can (0 for default)
1106  * - encoding: unused
1107  * - decoding: Set by user.
1108  * @deprecated use "downmix" codec private option
1109  */
1111  uint64_t request_channel_layout;
1112 #endif
1113 
1114  /**
1115  * Type of service that the audio stream conveys.
1116  * - encoding: Set by user.
1117  * - decoding: Set by libavcodec.
1118  */
1120 
1121  /**
1122  * desired sample format
1123  * - encoding: Not used.
1124  * - decoding: Set by user.
1125  * Decoder will decode to this format if it can.
1126  */
1128 
1129  /**
1130  * This callback is called at the beginning of each frame to get data
1131  * buffer(s) for it. There may be one contiguous buffer for all the data or
1132  * there may be a buffer per each data plane or anything in between. What
1133  * this means is, you may set however many entries in buf[] you feel necessary.
1134  * Each buffer must be reference-counted using the AVBuffer API (see description
1135  * of buf[] below).
1136  *
1137  * The following fields will be set in the frame before this callback is
1138  * called:
1139  * - format
1140  * - width, height (video only)
1141  * - sample_rate, channel_layout, nb_samples (audio only)
1142  * Their values may differ from the corresponding values in
1143  * AVCodecContext. This callback must use the frame values, not the codec
1144  * context values, to calculate the required buffer size.
1145  *
1146  * This callback must fill the following fields in the frame:
1147  * - data[]
1148  * - linesize[]
1149  * - extended_data:
1150  * * if the data is planar audio with more than 8 channels, then this
1151  * callback must allocate and fill extended_data to contain all pointers
1152  * to all data planes. data[] must hold as many pointers as it can.
1153  * extended_data must be allocated with av_malloc() and will be freed in
1154  * av_frame_unref().
1155  * * otherwise extended_data must point to data
1156  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1157  * the frame's data and extended_data pointers must be contained in these. That
1158  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1159  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1160  * and av_buffer_ref().
1161  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1162  * this callback and filled with the extra buffers if there are more
1163  * buffers than buf[] can hold. extended_buf will be freed in
1164  * av_frame_unref().
1165  *
1166  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1167  * avcodec_default_get_buffer2() instead of providing buffers allocated by
1168  * some other means.
1169  *
1170  * Each data plane must be aligned to the maximum required by the target
1171  * CPU.
1172  *
1173  * @see avcodec_default_get_buffer2()
1174  *
1175  * Video:
1176  *
1177  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1178  * (read and/or written to if it is writable) later by libavcodec.
1179  *
1180  * avcodec_align_dimensions2() should be used to find the required width and
1181  * height, as they normally need to be rounded up to the next multiple of 16.
1182  *
1183  * Some decoders do not support linesizes changing between frames.
1184  *
1185  * If frame multithreading is used, this callback may be called from a
1186  * different thread, but not from more than one at once. Does not need to be
1187  * reentrant.
1188  *
1189  * @see avcodec_align_dimensions2()
1190  *
1191  * Audio:
1192  *
1193  * Decoders request a buffer of a particular size by setting
1194  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1195  * however, utilize only part of the buffer by setting AVFrame.nb_samples
1196  * to a smaller value in the output frame.
1197  *
1198  * As a convenience, av_samples_get_buffer_size() and
1199  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1200  * functions to find the required data size and to fill data pointers and
1201  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1202  * since all planes must be the same size.
1203  *
1204  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1205  *
1206  * - encoding: unused
1207  * - decoding: Set by libavcodec, user can override.
1208  */
1210 
1211  /* - encoding parameters */
1212  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1213  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1214 
1215  /**
1216  * minimum quantizer
1217  * - encoding: Set by user.
1218  * - decoding: unused
1219  */
1220  int qmin;
1221 
1222  /**
1223  * maximum quantizer
1224  * - encoding: Set by user.
1225  * - decoding: unused
1226  */
1227  int qmax;
1228 
1229  /**
1230  * maximum quantizer difference between frames
1231  * - encoding: Set by user.
1232  * - decoding: unused
1233  */
1235 
1236  /**
1237  * decoder bitstream buffer size
1238  * - encoding: Set by user.
1239  * - decoding: unused
1240  */
1242 
1243  /**
1244  * ratecontrol override, see RcOverride
1245  * - encoding: Allocated/set/freed by user.
1246  * - decoding: unused
1247  */
1250 
1251  /**
1252  * maximum bitrate
1253  * - encoding: Set by user.
1254  * - decoding: Set by user, may be overwritten by libavcodec.
1255  */
1256  int64_t rc_max_rate;
1257 
1258  /**
1259  * minimum bitrate
1260  * - encoding: Set by user.
1261  * - decoding: unused
1262  */
1263  int64_t rc_min_rate;
1264 
1265  /**
1266  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1267  * - encoding: Set by user.
1268  * - decoding: unused.
1269  */
1271 
1272  /**
1273  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1274  * - encoding: Set by user.
1275  * - decoding: unused.
1276  */
1278 
1279  /**
1280  * Number of bits which should be loaded into the rc buffer before decoding starts.
1281  * - encoding: Set by user.
1282  * - decoding: unused
1283  */
1285 
1286  /**
1287  * trellis RD quantization
1288  * - encoding: Set by user.
1289  * - decoding: unused
1290  */
1291  int trellis;
1292 
1293  /**
1294  * pass1 encoding statistics output buffer
1295  * - encoding: Set by libavcodec.
1296  * - decoding: unused
1297  */
1298  char *stats_out;
1299 
1300  /**
1301  * pass2 encoding statistics input buffer
1302  * Concatenated stuff from stats_out of pass1 should be placed here.
1303  * - encoding: Allocated/set/freed by user.
1304  * - decoding: unused
1305  */
1306  char *stats_in;
1307 
1308  /**
1309  * Work around bugs in encoders which sometimes cannot be detected automatically.
1310  * - encoding: Set by user
1311  * - decoding: Set by user
1312  */
1314 #define FF_BUG_AUTODETECT 1 ///< autodetection
1315 #define FF_BUG_XVID_ILACE 4
1316 #define FF_BUG_UMP4 8
1317 #define FF_BUG_NO_PADDING 16
1318 #define FF_BUG_AMV 32
1319 #define FF_BUG_QPEL_CHROMA 64
1320 #define FF_BUG_STD_QPEL 128
1321 #define FF_BUG_QPEL_CHROMA2 256
1322 #define FF_BUG_DIRECT_BLOCKSIZE 512
1323 #define FF_BUG_EDGE 1024
1324 #define FF_BUG_HPEL_CHROMA 2048
1325 #define FF_BUG_DC_CLIP 4096
1326 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1327 #define FF_BUG_TRUNCATED 16384
1328 #define FF_BUG_IEDGE 32768
1329 
1330  /**
1331  * strictly follow the standard (MPEG-4, ...).
1332  * - encoding: Set by user.
1333  * - decoding: Set by user.
1334  * Setting this to STRICT or higher means the encoder and decoder will
1335  * generally do stupid things, whereas setting it to unofficial or lower
1336  * will mean the encoder might produce output that is not supported by all
1337  * spec-compliant decoders. Decoders don't differentiate between normal,
1338  * unofficial and experimental (that is, they always try to decode things
1339  * when they can) unless they are explicitly asked to behave stupidly
1340  * (=strictly conform to the specs)
1341  * This may only be set to one of the FF_COMPLIANCE_* values in defs.h.
1342  */
1344 
1345  /**
1346  * error concealment flags
1347  * - encoding: unused
1348  * - decoding: Set by user.
1349  */
1351 #define FF_EC_GUESS_MVS 1
1352 #define FF_EC_DEBLOCK 2
1353 #define FF_EC_FAVOR_INTER 256
1354 
1355  /**
1356  * debug
1357  * - encoding: Set by user.
1358  * - decoding: Set by user.
1359  */
1360  int debug;
1361 #define FF_DEBUG_PICT_INFO 1
1362 #define FF_DEBUG_RC 2
1363 #define FF_DEBUG_BITSTREAM 4
1364 #define FF_DEBUG_MB_TYPE 8
1365 #define FF_DEBUG_QP 16
1366 #define FF_DEBUG_DCT_COEFF 0x00000040
1367 #define FF_DEBUG_SKIP 0x00000080
1368 #define FF_DEBUG_STARTCODE 0x00000100
1369 #define FF_DEBUG_ER 0x00000400
1370 #define FF_DEBUG_MMCO 0x00000800
1371 #define FF_DEBUG_BUGS 0x00001000
1372 #define FF_DEBUG_BUFFERS 0x00008000
1373 #define FF_DEBUG_THREADS 0x00010000
1374 #define FF_DEBUG_GREEN_MD 0x00800000
1375 #define FF_DEBUG_NOMC 0x01000000
1376 
1377  /**
1378  * Error recognition; may misdetect some more or less valid parts as errors.
1379  * This is a bitfield of the AV_EF_* values defined in defs.h.
1380  *
1381  * - encoding: Set by user.
1382  * - decoding: Set by user.
1383  */
1385 
1386  /**
1387  * opaque 64-bit number (generally a PTS) that will be reordered and
1388  * output in AVFrame.reordered_opaque
1389  * - encoding: Set by libavcodec to the reordered_opaque of the input
1390  * frame corresponding to the last returned packet. Only
1391  * supported by encoders with the
1392  * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1393  * - decoding: Set by user.
1394  */
1396 
1397  /**
1398  * Hardware accelerator in use
1399  * - encoding: unused.
1400  * - decoding: Set by libavcodec
1401  */
1402  const struct AVHWAccel *hwaccel;
1403 
1404  /**
1405  * Legacy hardware accelerator context.
1406  *
1407  * For some hardware acceleration methods, the caller may use this field to
1408  * signal hwaccel-specific data to the codec. The struct pointed to by this
1409  * pointer is hwaccel-dependent and defined in the respective header. Please
1410  * refer to the FFmpeg HW accelerator documentation to know how to fill
1411  * this.
1412  *
1413  * In most cases this field is optional - the necessary information may also
1414  * be provided to libavcodec through @ref hw_frames_ctx or @ref
1415  * hw_device_ctx (see avcodec_get_hw_config()). However, in some cases it
1416  * may be the only method of signalling some (optional) information.
1417  *
1418  * The struct and its contents are owned by the caller.
1419  *
1420  * - encoding: May be set by the caller before avcodec_open2(). Must remain
1421  * valid until avcodec_free_context().
1422  * - decoding: May be set by the caller in the get_format() callback.
1423  * Must remain valid until the next get_format() call,
1424  * or avcodec_free_context() (whichever comes first).
1425  */
1427 
1428  /**
1429  * error
1430  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1431  * - decoding: unused
1432  */
1434 
1435  /**
1436  * DCT algorithm, see FF_DCT_* below
1437  * - encoding: Set by user.
1438  * - decoding: unused
1439  */
1441 #define FF_DCT_AUTO 0
1442 #define FF_DCT_FASTINT 1
1443 #define FF_DCT_INT 2
1444 #define FF_DCT_MMX 3
1445 #define FF_DCT_ALTIVEC 5
1446 #define FF_DCT_FAAN 6
1447 
1448  /**
1449  * IDCT algorithm, see FF_IDCT_* below.
1450  * - encoding: Set by user.
1451  * - decoding: Set by user.
1452  */
1454 #define FF_IDCT_AUTO 0
1455 #define FF_IDCT_INT 1
1456 #define FF_IDCT_SIMPLE 2
1457 #define FF_IDCT_SIMPLEMMX 3
1458 #define FF_IDCT_ARM 7
1459 #define FF_IDCT_ALTIVEC 8
1460 #define FF_IDCT_SIMPLEARM 10
1461 #define FF_IDCT_XVID 14
1462 #define FF_IDCT_SIMPLEARMV5TE 16
1463 #define FF_IDCT_SIMPLEARMV6 17
1464 #define FF_IDCT_FAAN 20
1465 #define FF_IDCT_SIMPLENEON 22
1466 #if FF_API_IDCT_NONE
1467 // formerly used by xvmc
1468 #define FF_IDCT_NONE 24
1469 #endif
1470 #define FF_IDCT_SIMPLEAUTO 128
1471 
1472  /**
1473  * bits per sample/pixel from the demuxer (needed for huffyuv).
1474  * - encoding: Set by libavcodec.
1475  * - decoding: Set by user.
1476  */
1478 
1479  /**
1480  * Bits per sample/pixel of internal libavcodec pixel/sample format.
1481  * - encoding: set by user.
1482  * - decoding: set by libavcodec.
1483  */
1485 
1486  /**
1487  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1488  * - encoding: unused
1489  * - decoding: Set by user.
1490  */
1491  int lowres;
1492 
1493  /**
1494  * thread count
1495  * is used to decide how many independent tasks should be passed to execute()
1496  * - encoding: Set by user.
1497  * - decoding: Set by user.
1498  */
1500 
1501  /**
1502  * Which multithreading methods to use.
1503  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1504  * so clients which cannot provide future frames should not use it.
1505  *
1506  * - encoding: Set by user, otherwise the default is used.
1507  * - decoding: Set by user, otherwise the default is used.
1508  */
1510 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1511 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1512 
1513  /**
1514  * Which multithreading methods are in use by the codec.
1515  * - encoding: Set by libavcodec.
1516  * - decoding: Set by libavcodec.
1517  */
1519 
1520 #if FF_API_THREAD_SAFE_CALLBACKS
1521  /**
1522  * Set by the client if its custom get_buffer() callback can be called
1523  * synchronously from another thread, which allows faster multithreaded decoding.
1524  * draw_horiz_band() will be called from other threads regardless of this setting.
1525  * Ignored if the default get_buffer() is used.
1526  * - encoding: Set by user.
1527  * - decoding: Set by user.
1528  *
1529  * @deprecated the custom get_buffer2() callback should always be
1530  * thread-safe. Thread-unsafe get_buffer2() implementations will be
1531  * invalid starting with LIBAVCODEC_VERSION_MAJOR=60; in other words,
1532  * libavcodec will behave as if this field was always set to 1.
1533  * Callers that want to be forward compatible with future libavcodec
1534  * versions should wrap access to this field in
1535  * `#if LIBAVCODEC_VERSION_MAJOR < 60`
1536  */
1539 #endif
1540 
1541  /**
1542  * The codec may call this to execute several independent things.
1543  * It will return only after finishing all tasks.
1544  * The user may replace this with some multithreaded implementation,
1545  * the default implementation will execute the parts serially.
1546  * @param count the number of things to execute
1547  * - encoding: Set by libavcodec, user can override.
1548  * - decoding: Set by libavcodec, user can override.
1549  */
1550  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1551 
1552  /**
1553  * The codec may call this to execute several independent things.
1554  * It will return only after finishing all tasks.
1555  * The user may replace this with some multithreaded implementation,
1556  * the default implementation will execute the parts serially.
1557  * @param c context passed also to func
1558  * @param count the number of things to execute
1559  * @param arg2 argument passed unchanged to func
1560  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1561  * @param func function that will be called count times, with jobnr from 0 to count-1.
1562  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1563  * two instances of func executing at the same time will have the same threadnr.
1564  * @return always 0 currently, but code should handle a future improvement where when any call to func
1565  * returns < 0 no further calls to func may be done and < 0 is returned.
1566  * - encoding: Set by libavcodec, user can override.
1567  * - decoding: Set by libavcodec, user can override.
1568  */
1569  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1570 
1571  /**
1572  * noise vs. sse weight for the nsse comparison function
1573  * - encoding: Set by user.
1574  * - decoding: unused
1575  */
1577 
1578  /**
1579  * profile
1580  * - encoding: Set by user.
1581  * - decoding: Set by libavcodec.
1582  */
1583  int profile;
1584 #define FF_PROFILE_UNKNOWN -99
1585 #define FF_PROFILE_RESERVED -100
1586 
1587 #define FF_PROFILE_AAC_MAIN 0
1588 #define FF_PROFILE_AAC_LOW 1
1589 #define FF_PROFILE_AAC_SSR 2
1590 #define FF_PROFILE_AAC_LTP 3
1591 #define FF_PROFILE_AAC_HE 4
1592 #define FF_PROFILE_AAC_HE_V2 28
1593 #define FF_PROFILE_AAC_LD 22
1594 #define FF_PROFILE_AAC_ELD 38
1595 #define FF_PROFILE_MPEG2_AAC_LOW 128
1596 #define FF_PROFILE_MPEG2_AAC_HE 131
1597 
1598 #define FF_PROFILE_DNXHD 0
1599 #define FF_PROFILE_DNXHR_LB 1
1600 #define FF_PROFILE_DNXHR_SQ 2
1601 #define FF_PROFILE_DNXHR_HQ 3
1602 #define FF_PROFILE_DNXHR_HQX 4
1603 #define FF_PROFILE_DNXHR_444 5
1604 
1605 #define FF_PROFILE_DTS 20
1606 #define FF_PROFILE_DTS_ES 30
1607 #define FF_PROFILE_DTS_96_24 40
1608 #define FF_PROFILE_DTS_HD_HRA 50
1609 #define FF_PROFILE_DTS_HD_MA 60
1610 #define FF_PROFILE_DTS_EXPRESS 70
1611 
1612 #define FF_PROFILE_MPEG2_422 0
1613 #define FF_PROFILE_MPEG2_HIGH 1
1614 #define FF_PROFILE_MPEG2_SS 2
1615 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1616 #define FF_PROFILE_MPEG2_MAIN 4
1617 #define FF_PROFILE_MPEG2_SIMPLE 5
1618 
1619 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1620 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1621 
1622 #define FF_PROFILE_H264_BASELINE 66
1623 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1624 #define FF_PROFILE_H264_MAIN 77
1625 #define FF_PROFILE_H264_EXTENDED 88
1626 #define FF_PROFILE_H264_HIGH 100
1627 #define FF_PROFILE_H264_HIGH_10 110
1628 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1629 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1630 #define FF_PROFILE_H264_HIGH_422 122
1631 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1632 #define FF_PROFILE_H264_STEREO_HIGH 128
1633 #define FF_PROFILE_H264_HIGH_444 144
1634 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1635 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1636 #define FF_PROFILE_H264_CAVLC_444 44
1637 
1638 #define FF_PROFILE_VC1_SIMPLE 0
1639 #define FF_PROFILE_VC1_MAIN 1
1640 #define FF_PROFILE_VC1_COMPLEX 2
1641 #define FF_PROFILE_VC1_ADVANCED 3
1642 
1643 #define FF_PROFILE_MPEG4_SIMPLE 0
1644 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1645 #define FF_PROFILE_MPEG4_CORE 2
1646 #define FF_PROFILE_MPEG4_MAIN 3
1647 #define FF_PROFILE_MPEG4_N_BIT 4
1648 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1649 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1650 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1651 #define FF_PROFILE_MPEG4_HYBRID 8
1652 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1653 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1654 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1655 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1656 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1657 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1658 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1659 
1660 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1661 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1662 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1663 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1664 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1665 
1666 #define FF_PROFILE_VP9_0 0
1667 #define FF_PROFILE_VP9_1 1
1668 #define FF_PROFILE_VP9_2 2
1669 #define FF_PROFILE_VP9_3 3
1670 
1671 #define FF_PROFILE_HEVC_MAIN 1
1672 #define FF_PROFILE_HEVC_MAIN_10 2
1673 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1674 #define FF_PROFILE_HEVC_REXT 4
1675 
1676 #define FF_PROFILE_VVC_MAIN_10 1
1677 #define FF_PROFILE_VVC_MAIN_10_444 33
1678 
1679 #define FF_PROFILE_AV1_MAIN 0
1680 #define FF_PROFILE_AV1_HIGH 1
1681 #define FF_PROFILE_AV1_PROFESSIONAL 2
1682 
1683 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1684 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1685 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1686 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1687 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1688 
1689 #define FF_PROFILE_SBC_MSBC 1
1690 
1691 #define FF_PROFILE_PRORES_PROXY 0
1692 #define FF_PROFILE_PRORES_LT 1
1693 #define FF_PROFILE_PRORES_STANDARD 2
1694 #define FF_PROFILE_PRORES_HQ 3
1695 #define FF_PROFILE_PRORES_4444 4
1696 #define FF_PROFILE_PRORES_XQ 5
1697 
1698 #define FF_PROFILE_ARIB_PROFILE_A 0
1699 #define FF_PROFILE_ARIB_PROFILE_C 1
1700 
1701 #define FF_PROFILE_KLVA_SYNC 0
1702 #define FF_PROFILE_KLVA_ASYNC 1
1703 
1704  /**
1705  * level
1706  * - encoding: Set by user.
1707  * - decoding: Set by libavcodec.
1708  */
1709  int level;
1710 #define FF_LEVEL_UNKNOWN -99
1711 
1712  /**
1713  * Skip loop filtering for selected frames.
1714  * - encoding: unused
1715  * - decoding: Set by user.
1716  */
1718 
1719  /**
1720  * Skip IDCT/dequantization for selected frames.
1721  * - encoding: unused
1722  * - decoding: Set by user.
1723  */
1725 
1726  /**
1727  * Skip decoding for selected frames.
1728  * - encoding: unused
1729  * - decoding: Set by user.
1730  */
1732 
1733  /**
1734  * Header containing style information for text subtitles.
1735  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
1736  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
1737  * the Format line following. It shouldn't include any Dialogue line.
1738  * - encoding: Set/allocated/freed by user (before avcodec_open2())
1739  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
1740  */
1743 
1744  /**
1745  * Audio only. The number of "priming" samples (padding) inserted by the
1746  * encoder at the beginning of the audio. I.e. this number of leading
1747  * decoded samples must be discarded by the caller to get the original audio
1748  * without leading padding.
1749  *
1750  * - decoding: unused
1751  * - encoding: Set by libavcodec. The timestamps on the output packets are
1752  * adjusted by the encoder so that they always refer to the
1753  * first sample of the data actually contained in the packet,
1754  * including any added padding. E.g. if the timebase is
1755  * 1/samplerate and the timestamp of the first input sample is
1756  * 0, the timestamp of the first output packet will be
1757  * -initial_padding.
1758  */
1760 
1761  /**
1762  * - decoding: For codecs that store a framerate value in the compressed
1763  * bitstream, the decoder may export it here. { 0, 1} when
1764  * unknown.
1765  * - encoding: May be used to signal the framerate of CFR content to an
1766  * encoder.
1767  */
1769 
1770  /**
1771  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
1772  * - encoding: unused.
1773  * - decoding: Set by libavcodec before calling get_format()
1774  */
1776 
1777  /**
1778  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
1779  * - encoding unused.
1780  * - decoding set by user.
1781  */
1783 
1784  /**
1785  * AVCodecDescriptor
1786  * - encoding: unused.
1787  * - decoding: set by libavcodec.
1788  */
1790 
1791  /**
1792  * Current statistics for PTS correction.
1793  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
1794  * - encoding: unused
1795  */
1796  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
1797  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
1798  int64_t pts_correction_last_pts; /// PTS of the last frame
1799  int64_t pts_correction_last_dts; /// DTS of the last frame
1800 
1801  /**
1802  * Character encoding of the input subtitles file.
1803  * - decoding: set by user
1804  * - encoding: unused
1805  */
1807 
1808  /**
1809  * Subtitles character encoding mode. Formats or codecs might be adjusting
1810  * this setting (if they are doing the conversion themselves for instance).
1811  * - decoding: set by libavcodec
1812  * - encoding: unused
1813  */
1815 #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)
1816 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
1817 #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
1818 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
1819 
1820  /**
1821  * Skip processing alpha if supported by codec.
1822  * Note that if the format uses pre-multiplied alpha (common with VP6,
1823  * and recommended due to better video quality/compression)
1824  * the image will look as if alpha-blended onto a black background.
1825  * However for formats that do not use pre-multiplied alpha
1826  * there might be serious artefacts (though e.g. libswscale currently
1827  * assumes pre-multiplied alpha anyway).
1828  *
1829  * - decoding: set by user
1830  * - encoding: unused
1831  */
1833 
1834  /**
1835  * Number of samples to skip after a discontinuity
1836  * - decoding: unused
1837  * - encoding: set by libavcodec
1838  */
1840 
1841 #if FF_API_DEBUG_MV
1842  /**
1843  * @deprecated unused
1844  */
1847 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
1848 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
1849 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
1850 #endif
1851 
1852  /**
1853  * custom intra quantization matrix
1854  * - encoding: Set by user, can be NULL.
1855  * - decoding: unused.
1856  */
1858 
1859  /**
1860  * dump format separator.
1861  * can be ", " or "\n " or anything else
1862  * - encoding: Set by user.
1863  * - decoding: Set by user.
1864  */
1865  uint8_t *dump_separator;
1866 
1867  /**
1868  * ',' separated list of allowed decoders.
1869  * If NULL then all are allowed
1870  * - encoding: unused
1871  * - decoding: set by user
1872  */
1874 
1875  /**
1876  * Properties of the stream that gets decoded
1877  * - encoding: unused
1878  * - decoding: set by libavcodec
1879  */
1880  unsigned properties;
1881 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
1882 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
1883 #define FF_CODEC_PROPERTY_FILM_GRAIN 0x00000004
1884 
1885  /**
1886  * Additional data associated with the entire coded stream.
1887  *
1888  * - decoding: unused
1889  * - encoding: may be set by libavcodec after avcodec_open2().
1890  */
1893 
1894  /**
1895  * A reference to the AVHWFramesContext describing the input (for encoding)
1896  * or output (decoding) frames. The reference is set by the caller and
1897  * afterwards owned (and freed) by libavcodec - it should never be read by
1898  * the caller after being set.
1899  *
1900  * - decoding: This field should be set by the caller from the get_format()
1901  * callback. The previous reference (if any) will always be
1902  * unreffed by libavcodec before the get_format() call.
1903  *
1904  * If the default get_buffer2() is used with a hwaccel pixel
1905  * format, then this AVHWFramesContext will be used for
1906  * allocating the frame buffers.
1907  *
1908  * - encoding: For hardware encoders configured to use a hwaccel pixel
1909  * format, this field should be set by the caller to a reference
1910  * to the AVHWFramesContext describing input frames.
1911  * AVHWFramesContext.format must be equal to
1912  * AVCodecContext.pix_fmt.
1913  *
1914  * This field should be set before avcodec_open2() is called.
1915  */
1917 
1918 #if FF_API_SUB_TEXT_FORMAT
1919  /**
1920  * @deprecated unused
1921  */
1924 #define FF_SUB_TEXT_FMT_ASS 0
1925 #endif
1926 
1927  /**
1928  * Audio only. The amount of padding (in samples) appended by the encoder to
1929  * the end of the audio. I.e. this number of decoded samples must be
1930  * discarded by the caller from the end of the stream to get the original
1931  * audio without any trailing padding.
1932  *
1933  * - decoding: unused
1934  * - encoding: unused
1935  */
1937 
1938  /**
1939  * The number of pixels per image to maximally accept.
1940  *
1941  * - decoding: set by user
1942  * - encoding: set by user
1943  */
1944  int64_t max_pixels;
1945 
1946  /**
1947  * A reference to the AVHWDeviceContext describing the device which will
1948  * be used by a hardware encoder/decoder. The reference is set by the
1949  * caller and afterwards owned (and freed) by libavcodec.
1950  *
1951  * This should be used if either the codec device does not require
1952  * hardware frames or any that are used are to be allocated internally by
1953  * libavcodec. If the user wishes to supply any of the frames used as
1954  * encoder input or decoder output then hw_frames_ctx should be used
1955  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
1956  * field will be ignored while decoding the associated stream segment, but
1957  * may again be used on a following one after another get_format() call.
1958  *
1959  * For both encoders and decoders this field should be set before
1960  * avcodec_open2() is called and must not be written to thereafter.
1961  *
1962  * Note that some decoders may require this field to be set initially in
1963  * order to support hw_frames_ctx at all - in that case, all frames
1964  * contexts used must be created on the same device.
1965  */
1967 
1968  /**
1969  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
1970  * decoding (if active).
1971  * - encoding: unused
1972  * - decoding: Set by user (either before avcodec_open2(), or in the
1973  * AVCodecContext.get_format callback)
1974  */
1976 
1977  /**
1978  * Video decoding only. Certain video codecs support cropping, meaning that
1979  * only a sub-rectangle of the decoded frame is intended for display. This
1980  * option controls how cropping is handled by libavcodec.
1981  *
1982  * When set to 1 (the default), libavcodec will apply cropping internally.
1983  * I.e. it will modify the output frame width/height fields and offset the
1984  * data pointers (only by as much as possible while preserving alignment, or
1985  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
1986  * the frames output by the decoder refer only to the cropped area. The
1987  * crop_* fields of the output frames will be zero.
1988  *
1989  * When set to 0, the width/height fields of the output frames will be set
1990  * to the coded dimensions and the crop_* fields will describe the cropping
1991  * rectangle. Applying the cropping is left to the caller.
1992  *
1993  * @warning When hardware acceleration with opaque output frames is used,
1994  * libavcodec is unable to apply cropping from the top/left border.
1995  *
1996  * @note when this option is set to zero, the width/height fields of the
1997  * AVCodecContext and output AVFrames have different meanings. The codec
1998  * context fields store display dimensions (with the coded dimensions in
1999  * coded_width/height), while the frame fields store the coded dimensions
2000  * (with the display dimensions being determined by the crop_* fields).
2001  */
2003 
2004  /*
2005  * Video decoding only. Sets the number of extra hardware frames which
2006  * the decoder will allocate for use by the caller. This must be set
2007  * before avcodec_open2() is called.
2008  *
2009  * Some hardware decoders require all frames that they will use for
2010  * output to be defined in advance before decoding starts. For such
2011  * decoders, the hardware frame pool must therefore be of a fixed size.
2012  * The extra frames set here are on top of any number that the decoder
2013  * needs internally in order to operate normally (for example, frames
2014  * used as reference pictures).
2015  */
2017 
2018  /**
2019  * The percentage of damaged samples to discard a frame.
2020  *
2021  * - decoding: set by user
2022  * - encoding: unused
2023  */
2025 
2026  /**
2027  * The number of samples per frame to maximally accept.
2028  *
2029  * - decoding: set by user
2030  * - encoding: set by user
2031  */
2032  int64_t max_samples;
2033 
2034  /**
2035  * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
2036  * metadata exported in frame, packet, or coded stream side data by
2037  * decoders and encoders.
2038  *
2039  * - decoding: set by user
2040  * - encoding: set by user
2041  */
2043 
2044  /**
2045  * This callback is called at the beginning of each packet to get a data
2046  * buffer for it.
2047  *
2048  * The following field will be set in the packet before this callback is
2049  * called:
2050  * - size
2051  * This callback must use the above value to calculate the required buffer size,
2052  * which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
2053  *
2054  * In some specific cases, the encoder may not use the entire buffer allocated by this
2055  * callback. This will be reflected in the size value in the packet once returned by
2056  * avcodec_receive_packet().
2057  *
2058  * This callback must fill the following fields in the packet:
2059  * - data: alignment requirements for AVPacket apply, if any. Some architectures and
2060  * encoders may benefit from having aligned data.
2061  * - buf: must contain a pointer to an AVBufferRef structure. The packet's
2062  * data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
2063  * and av_buffer_ref().
2064  *
2065  * If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2066  * avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2067  * some other means.
2068  *
2069  * The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2070  * They may be used for example to hint what use the buffer may get after being
2071  * created.
2072  * Implementations of this callback may ignore flags they don't understand.
2073  * If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2074  * (read and/or written to if it is writable) later by libavcodec.
2075  *
2076  * This callback must be thread-safe, as when frame threading is used, it may
2077  * be called from multiple threads simultaneously.
2078  *
2079  * @see avcodec_default_get_encode_buffer()
2080  *
2081  * - encoding: Set by libavcodec, user can override.
2082  * - decoding: unused
2083  */
2085 
2086  /**
2087  * Audio channel layout.
2088  * - encoding: must be set by the caller, to one of AVCodec.ch_layouts.
2089  * - decoding: may be set by the caller if known e.g. from the container.
2090  * The decoder can then override during decoding as needed.
2091  */
2093 } AVCodecContext;
2094 
2095 /**
2096  * @defgroup lavc_hwaccel AVHWAccel
2097  *
2098  * @note Nothing in this structure should be accessed by the user. At some
2099  * point in future it will not be externally visible at all.
2100  *
2101  * @{
2102  */
2103 typedef struct AVHWAccel {
2104  /**
2105  * Name of the hardware accelerated codec.
2106  * The name is globally unique among encoders and among decoders (but an
2107  * encoder and a decoder can share the same name).
2108  */
2109  const char *name;
2110 
2111  /**
2112  * Type of codec implemented by the hardware accelerator.
2113  *
2114  * See AVMEDIA_TYPE_xxx
2115  */
2117 
2118  /**
2119  * Codec implemented by the hardware accelerator.
2120  *
2121  * See AV_CODEC_ID_xxx
2122  */
2124 
2125  /**
2126  * Supported pixel format.
2127  *
2128  * Only hardware accelerated formats are supported here.
2129  */
2131 
2132  /**
2133  * Hardware accelerated codec capabilities.
2134  * see AV_HWACCEL_CODEC_CAP_*
2135  */
2137 
2138  /*****************************************************************
2139  * No fields below this line are part of the public API. They
2140  * may not be used outside of libavcodec and can be changed and
2141  * removed at will.
2142  * New public fields should be added right above.
2143  *****************************************************************
2144  */
2145 
2146  /**
2147  * Allocate a custom buffer
2148  */
2150 
2151  /**
2152  * Called at the beginning of each frame or field picture.
2153  *
2154  * Meaningful frame information (codec specific) is guaranteed to
2155  * be parsed at this point. This function is mandatory.
2156  *
2157  * Note that buf can be NULL along with buf_size set to 0.
2158  * Otherwise, this means the whole frame is available at this point.
2159  *
2160  * @param avctx the codec context
2161  * @param buf the frame data buffer base
2162  * @param buf_size the size of the frame in bytes
2163  * @return zero if successful, a negative value otherwise
2164  */
2165  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2166 
2167  /**
2168  * Callback for parameter data (SPS/PPS/VPS etc).
2169  *
2170  * Useful for hardware decoders which keep persistent state about the
2171  * video parameters, and need to receive any changes to update that state.
2172  *
2173  * @param avctx the codec context
2174  * @param type the nal unit type
2175  * @param buf the nal unit data buffer
2176  * @param buf_size the size of the nal unit in bytes
2177  * @return zero if successful, a negative value otherwise
2178  */
2179  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
2180 
2181  /**
2182  * Callback for each slice.
2183  *
2184  * Meaningful slice information (codec specific) is guaranteed to
2185  * be parsed at this point. This function is mandatory.
2186  *
2187  * @param avctx the codec context
2188  * @param buf the slice data buffer base
2189  * @param buf_size the size of the slice in bytes
2190  * @return zero if successful, a negative value otherwise
2191  */
2192  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2193 
2194  /**
2195  * Called at the end of each frame or field picture.
2196  *
2197  * The whole picture is parsed at this point and can now be sent
2198  * to the hardware accelerator. This function is mandatory.
2199  *
2200  * @param avctx the codec context
2201  * @return zero if successful, a negative value otherwise
2202  */
2204 
2205  /**
2206  * Size of per-frame hardware accelerator private data.
2207  *
2208  * Private data is allocated with av_mallocz() before
2209  * AVCodecContext.get_buffer() and deallocated after
2210  * AVCodecContext.release_buffer().
2211  */
2213 
2214  /**
2215  * Initialize the hwaccel private data.
2216  *
2217  * This will be called from ff_get_format(), after hwaccel and
2218  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
2219  * is allocated.
2220  */
2222 
2223  /**
2224  * Uninitialize the hwaccel private data.
2225  *
2226  * This will be called from get_format() or avcodec_close(), after hwaccel
2227  * and hwaccel_context are already uninitialized.
2228  */
2230 
2231  /**
2232  * Size of the private data to allocate in
2233  * AVCodecInternal.hwaccel_priv_data.
2234  */
2236 
2237  /**
2238  * Internal hwaccel capabilities.
2239  */
2241 
2242  /**
2243  * Fill the given hw_frames context with current codec parameters. Called
2244  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
2245  * details.
2246  *
2247  * This CAN be called before AVHWAccel.init is called, and you must assume
2248  * that avctx->hwaccel_priv_data is invalid.
2249  */
2250  int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
2251 } AVHWAccel;
2252 
2253 /**
2254  * HWAccel is experimental and is thus avoided in favor of non experimental
2255  * codecs
2256  */
2257 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2258 
2259 /**
2260  * Hardware acceleration should be used for decoding even if the codec level
2261  * used is unknown or higher than the maximum supported level reported by the
2262  * hardware driver.
2263  *
2264  * It's generally a good idea to pass this flag unless you have a specific
2265  * reason not to, as hardware tends to under-report supported levels.
2266  */
2267 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2268 
2269 /**
2270  * Hardware acceleration can output YUV pixel formats with a different chroma
2271  * sampling than 4:2:0 and/or other than 8 bits per component.
2272  */
2273 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2274 
2275 /**
2276  * Hardware acceleration should still be attempted for decoding when the
2277  * codec profile does not match the reported capabilities of the hardware.
2278  *
2279  * For example, this can be used to try to decode baseline profile H.264
2280  * streams in hardware - it will often succeed, because many streams marked
2281  * as baseline profile actually conform to constrained baseline profile.
2282  *
2283  * @warning If the stream is actually not supported then the behaviour is
2284  * undefined, and may include returning entirely incorrect output
2285  * while indicating success.
2286  */
2287 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2288 
2289 /**
2290  * Some hardware decoders (namely nvdec) can either output direct decoder
2291  * surfaces, or make an on-device copy and return said copy.
2292  * There is a hard limit on how many decoder surfaces there can be, and it
2293  * cannot be accurately guessed ahead of time.
2294  * For some processing chains, this can be okay, but others will run into the
2295  * limit and in turn produce very confusing errors that require fine tuning of
2296  * more or less obscure options by the user, or in extreme cases cannot be
2297  * resolved at all without inserting an avfilter that forces a copy.
2298  *
2299  * Thus, the hwaccel will by default make a copy for safety and resilience.
2300  * If a users really wants to minimize the amount of copies, they can set this
2301  * flag and ensure their processing chain does not exhaust the surface pool.
2302  */
2303 #define AV_HWACCEL_FLAG_UNSAFE_OUTPUT (1 << 3)
2304 
2305 /**
2306  * @}
2307  */
2308 
2311 
2312  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2313 
2314  /**
2315  * Plain text, the text field must be set by the decoder and is
2316  * authoritative. ass and pict fields may contain approximations.
2317  */
2319 
2320  /**
2321  * Formatted text, the ass field must be set by the decoder and is
2322  * authoritative. pict and text fields may contain approximations.
2323  */
2325 };
2326 
2327 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
2328 
2329 typedef struct AVSubtitleRect {
2330  int x; ///< top left corner of pict, undefined when pict is not set
2331  int y; ///< top left corner of pict, undefined when pict is not set
2332  int w; ///< width of pict, undefined when pict is not set
2333  int h; ///< height of pict, undefined when pict is not set
2334  int nb_colors; ///< number of colors in pict, undefined when pict is not set
2335 
2336  /**
2337  * data+linesize for the bitmap of this subtitle.
2338  * Can be set for text/ass as well once they are rendered.
2339  */
2340  uint8_t *data[4];
2341  int linesize[4];
2342 
2344 
2345  char *text; ///< 0 terminated plain UTF-8 text
2346 
2347  /**
2348  * 0 terminated ASS/SSA compatible event line.
2349  * The presentation of this is unaffected by the other values in this
2350  * struct.
2351  */
2352  char *ass;
2353 
2354  int flags;
2355 } AVSubtitleRect;
2356 
2357 typedef struct AVSubtitle {
2358  uint16_t format; /* 0 = graphics */
2359  uint32_t start_display_time; /* relative to packet pts, in ms */
2360  uint32_t end_display_time; /* relative to packet pts, in ms */
2361  unsigned num_rects;
2363  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2364 } AVSubtitle;
2365 
2366 /**
2367  * Return the LIBAVCODEC_VERSION_INT constant.
2368  */
2369 unsigned avcodec_version(void);
2370 
2371 /**
2372  * Return the libavcodec build-time configuration.
2373  */
2374 const char *avcodec_configuration(void);
2375 
2376 /**
2377  * Return the libavcodec license.
2378  */
2379 const char *avcodec_license(void);
2380 
2381 /**
2382  * Allocate an AVCodecContext and set its fields to default values. The
2383  * resulting struct should be freed with avcodec_free_context().
2384  *
2385  * @param codec if non-NULL, allocate private data and initialize defaults
2386  * for the given codec. It is illegal to then call avcodec_open2()
2387  * with a different codec.
2388  * If NULL, then the codec-specific defaults won't be initialized,
2389  * which may result in suboptimal default settings (this is
2390  * important mainly for encoders, e.g. libx264).
2391  *
2392  * @return An AVCodecContext filled with default values or NULL on failure.
2393  */
2395 
2396 /**
2397  * Free the codec context and everything associated with it and write NULL to
2398  * the provided pointer.
2399  */
2400 void avcodec_free_context(AVCodecContext **avctx);
2401 
2402 /**
2403  * Get the AVClass for AVCodecContext. It can be used in combination with
2404  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2405  *
2406  * @see av_opt_find().
2407  */
2408 const AVClass *avcodec_get_class(void);
2409 
2410 #if FF_API_GET_FRAME_CLASS
2411 /**
2412  * @deprecated This function should not be used.
2413  */
2415 const AVClass *avcodec_get_frame_class(void);
2416 #endif
2417 
2418 /**
2419  * Get the AVClass for AVSubtitleRect. It can be used in combination with
2420  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2421  *
2422  * @see av_opt_find().
2423  */
2425 
2426 /**
2427  * Fill the parameters struct based on the values from the supplied codec
2428  * context. Any allocated fields in par are freed and replaced with duplicates
2429  * of the corresponding fields in codec.
2430  *
2431  * @return >= 0 on success, a negative AVERROR code on failure
2432  */
2434  const AVCodecContext *codec);
2435 
2436 /**
2437  * Fill the codec context based on the values from the supplied codec
2438  * parameters. Any allocated fields in codec that have a corresponding field in
2439  * par are freed and replaced with duplicates of the corresponding field in par.
2440  * Fields in codec that do not have a counterpart in par are not touched.
2441  *
2442  * @return >= 0 on success, a negative AVERROR code on failure.
2443  */
2445  const AVCodecParameters *par);
2446 
2447 /**
2448  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2449  * function the context has to be allocated with avcodec_alloc_context3().
2450  *
2451  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2452  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2453  * retrieving a codec.
2454  *
2455  * @note Always call this function before using decoding routines (such as
2456  * @ref avcodec_receive_frame()).
2457  *
2458  * @code
2459  * av_dict_set(&opts, "b", "2.5M", 0);
2460  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2461  * if (!codec)
2462  * exit(1);
2463  *
2464  * context = avcodec_alloc_context3(codec);
2465  *
2466  * if (avcodec_open2(context, codec, opts) < 0)
2467  * exit(1);
2468  * @endcode
2469  *
2470  * @param avctx The context to initialize.
2471  * @param codec The codec to open this context for. If a non-NULL codec has been
2472  * previously passed to avcodec_alloc_context3() or
2473  * for this context, then this parameter MUST be either NULL or
2474  * equal to the previously passed codec.
2475  * @param options A dictionary filled with AVCodecContext and codec-private options.
2476  * On return this object will be filled with options that were not found.
2477  *
2478  * @return zero on success, a negative value on error
2479  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2480  * av_dict_set(), av_opt_find().
2481  */
2482 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2483 
2484 /**
2485  * Close a given AVCodecContext and free all the data associated with it
2486  * (but not the AVCodecContext itself).
2487  *
2488  * Calling this function on an AVCodecContext that hasn't been opened will free
2489  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2490  * codec. Subsequent calls will do nothing.
2491  *
2492  * @note Do not use this function. Use avcodec_free_context() to destroy a
2493  * codec context (either open or closed). Opening and closing a codec context
2494  * multiple times is not supported anymore -- use multiple codec contexts
2495  * instead.
2496  */
2497 int avcodec_close(AVCodecContext *avctx);
2498 
2499 /**
2500  * Free all allocated data in the given subtitle struct.
2501  *
2502  * @param sub AVSubtitle to free.
2503  */
2505 
2506 /**
2507  * @}
2508  */
2509 
2510 /**
2511  * @addtogroup lavc_decoding
2512  * @{
2513  */
2514 
2515 /**
2516  * The default callback for AVCodecContext.get_buffer2(). It is made public so
2517  * it can be called by custom get_buffer2() implementations for decoders without
2518  * AV_CODEC_CAP_DR1 set.
2519  */
2521 
2522 /**
2523  * The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2524  * it can be called by custom get_encode_buffer() implementations for encoders without
2525  * AV_CODEC_CAP_DR1 set.
2526  */
2528 
2529 /**
2530  * Modify width and height values so that they will result in a memory
2531  * buffer that is acceptable for the codec if you do not use any horizontal
2532  * padding.
2533  *
2534  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2535  */
2537 
2538 /**
2539  * Modify width and height values so that they will result in a memory
2540  * buffer that is acceptable for the codec if you also ensure that all
2541  * line sizes are a multiple of the respective linesize_align[i].
2542  *
2543  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2544  */
2546  int linesize_align[AV_NUM_DATA_POINTERS]);
2547 
2548 #ifdef FF_API_AVCODEC_CHROMA_POS
2549 /**
2550  * Converts AVChromaLocation to swscale x/y chroma position.
2551  *
2552  * The positions represent the chroma (0,0) position in a coordinates system
2553  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2554  *
2555  * @param xpos horizontal chroma sample position
2556  * @param ypos vertical chroma sample position
2557  * @deprecated Use av_chroma_location_enum_to_pos() instead.
2558  */
2560 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
2561 
2562 /**
2563  * Converts swscale x/y chroma position to AVChromaLocation.
2564  *
2565  * The positions represent the chroma (0,0) position in a coordinates system
2566  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2567  *
2568  * @param xpos horizontal chroma sample position
2569  * @param ypos vertical chroma sample position
2570  * @deprecated Use av_chroma_location_pos_to_enum() instead.
2571  */
2573 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
2574 #endif
2575 
2576 /**
2577  * Decode a subtitle message.
2578  * Return a negative value on error, otherwise return the number of bytes used.
2579  * If no subtitle could be decompressed, got_sub_ptr is zero.
2580  * Otherwise, the subtitle is stored in *sub.
2581  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
2582  * simplicity, because the performance difference is expected to be negligible
2583  * and reusing a get_buffer written for video codecs would probably perform badly
2584  * due to a potentially very different allocation pattern.
2585  *
2586  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2587  * and output. This means that for some packets they will not immediately
2588  * produce decoded output and need to be flushed at the end of decoding to get
2589  * all the decoded data. Flushing is done by calling this function with packets
2590  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2591  * returning subtitles. It is safe to flush even those decoders that are not
2592  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
2593  *
2594  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2595  * before packets may be fed to the decoder.
2596  *
2597  * @param avctx the codec context
2598  * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
2599  * must be freed with avsubtitle_free if *got_sub_ptr is set.
2600  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
2601  * @param[in] avpkt The input AVPacket containing the input buffer.
2602  */
2604  int *got_sub_ptr,
2605  AVPacket *avpkt);
2606 
2607 /**
2608  * Supply raw packet data as input to a decoder.
2609  *
2610  * Internally, this call will copy relevant AVCodecContext fields, which can
2611  * influence decoding per-packet, and apply them when the packet is actually
2612  * decoded. (For example AVCodecContext.skip_frame, which might direct the
2613  * decoder to drop the frame contained by the packet sent with this function.)
2614  *
2615  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2616  * larger than the actual read bytes because some optimized bitstream
2617  * readers read 32 or 64 bits at once and could read over the end.
2618  *
2619  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2620  * before packets may be fed to the decoder.
2621  *
2622  * @param avctx codec context
2623  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
2624  * frame, or several complete audio frames.
2625  * Ownership of the packet remains with the caller, and the
2626  * decoder will not write to the packet. The decoder may create
2627  * a reference to the packet data (or copy it if the packet is
2628  * not reference-counted).
2629  * Unlike with older APIs, the packet is always fully consumed,
2630  * and if it contains multiple frames (e.g. some audio codecs),
2631  * will require you to call avcodec_receive_frame() multiple
2632  * times afterwards before you can send a new packet.
2633  * It can be NULL (or an AVPacket with data set to NULL and
2634  * size set to 0); in this case, it is considered a flush
2635  * packet, which signals the end of the stream. Sending the
2636  * first flush packet will return success. Subsequent ones are
2637  * unnecessary and will return AVERROR_EOF. If the decoder
2638  * still has frames buffered, it will return them after sending
2639  * a flush packet.
2640  *
2641  * @retval 0 success
2642  * @retval AVERROR(EAGAIN) input is not accepted in the current state - user
2643  * must read output with avcodec_receive_frame() (once
2644  * all output is read, the packet should be resent,
2645  * and the call will not fail with EAGAIN).
2646  * @retval AVERROR_EOF the decoder has been flushed, and no new packets can be
2647  * sent to it (also returned if more than 1 flush
2648  * packet is sent)
2649  * @retval AVERROR(EINVAL) codec not opened, it is an encoder, or requires flush
2650  * @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
2651  * @retval "another negative error code" legitimate decoding errors
2652  */
2653 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
2654 
2655 /**
2656  * Return decoded output data from a decoder or encoder (when the
2657  * AV_CODEC_FLAG_RECON_FRAME flag is used).
2658  *
2659  * @param avctx codec context
2660  * @param frame This will be set to a reference-counted video or audio
2661  * frame (depending on the decoder type) allocated by the
2662  * codec. Note that the function will always call
2663  * av_frame_unref(frame) before doing anything else.
2664  *
2665  * @retval 0 success, a frame was returned
2666  * @retval AVERROR(EAGAIN) output is not available in this state - user must
2667  * try to send new input
2668  * @retval AVERROR_EOF the codec has been fully flushed, and there will be
2669  * no more output frames
2670  * @retval AVERROR(EINVAL) codec not opened, or it is an encoder without the
2671  * AV_CODEC_FLAG_RECON_FRAME flag enabled
2672  * @retval AVERROR_INPUT_CHANGED current decoded frame has changed parameters with
2673  * respect to first decoded frame. Applicable when flag
2674  * AV_CODEC_FLAG_DROPCHANGED is set.
2675  * @retval "other negative error code" legitimate decoding errors
2676  */
2678 
2679 /**
2680  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
2681  * to retrieve buffered output packets.
2682  *
2683  * @param avctx codec context
2684  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
2685  * Ownership of the frame remains with the caller, and the
2686  * encoder will not write to the frame. The encoder may create
2687  * a reference to the frame data (or copy it if the frame is
2688  * not reference-counted).
2689  * It can be NULL, in which case it is considered a flush
2690  * packet. This signals the end of the stream. If the encoder
2691  * still has packets buffered, it will return them after this
2692  * call. Once flushing mode has been entered, additional flush
2693  * packets are ignored, and sending frames will return
2694  * AVERROR_EOF.
2695  *
2696  * For audio:
2697  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
2698  * can have any number of samples.
2699  * If it is not set, frame->nb_samples must be equal to
2700  * avctx->frame_size for all frames except the last.
2701  * The final frame may be smaller than avctx->frame_size.
2702  * @retval 0 success
2703  * @retval AVERROR(EAGAIN) input is not accepted in the current state - user must
2704  * read output with avcodec_receive_packet() (once all
2705  * output is read, the packet should be resent, and the
2706  * call will not fail with EAGAIN).
2707  * @retval AVERROR_EOF the encoder has been flushed, and no new frames can
2708  * be sent to it
2709  * @retval AVERROR(EINVAL) codec not opened, it is a decoder, or requires flush
2710  * @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
2711  * @retval "another negative error code" legitimate encoding errors
2712  */
2713 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
2714 
2715 /**
2716  * Read encoded data from the encoder.
2717  *
2718  * @param avctx codec context
2719  * @param avpkt This will be set to a reference-counted packet allocated by the
2720  * encoder. Note that the function will always call
2721  * av_packet_unref(avpkt) before doing anything else.
2722  * @retval 0 success
2723  * @retval AVERROR(EAGAIN) output is not available in the current state - user must
2724  * try to send input
2725  * @retval AVERROR_EOF the encoder has been fully flushed, and there will be no
2726  * more output packets
2727  * @retval AVERROR(EINVAL) codec not opened, or it is a decoder
2728  * @retval "another negative error code" legitimate encoding errors
2729  */
2730 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
2731 
2732 /**
2733  * Create and return a AVHWFramesContext with values adequate for hardware
2734  * decoding. This is meant to get called from the get_format callback, and is
2735  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
2736  * This API is for decoding with certain hardware acceleration modes/APIs only.
2737  *
2738  * The returned AVHWFramesContext is not initialized. The caller must do this
2739  * with av_hwframe_ctx_init().
2740  *
2741  * Calling this function is not a requirement, but makes it simpler to avoid
2742  * codec or hardware API specific details when manually allocating frames.
2743  *
2744  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
2745  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
2746  * it unnecessary to call this function or having to care about
2747  * AVHWFramesContext initialization at all.
2748  *
2749  * There are a number of requirements for calling this function:
2750  *
2751  * - It must be called from get_format with the same avctx parameter that was
2752  * passed to get_format. Calling it outside of get_format is not allowed, and
2753  * can trigger undefined behavior.
2754  * - The function is not always supported (see description of return values).
2755  * Even if this function returns successfully, hwaccel initialization could
2756  * fail later. (The degree to which implementations check whether the stream
2757  * is actually supported varies. Some do this check only after the user's
2758  * get_format callback returns.)
2759  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
2760  * user decides to use a AVHWFramesContext prepared with this API function,
2761  * the user must return the same hw_pix_fmt from get_format.
2762  * - The device_ref passed to this function must support the given hw_pix_fmt.
2763  * - After calling this API function, it is the user's responsibility to
2764  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
2765  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
2766  * before returning from get_format (this is implied by the normal
2767  * AVCodecContext.hw_frames_ctx API rules).
2768  * - The AVHWFramesContext parameters may change every time time get_format is
2769  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
2770  * you are inherently required to go through this process again on every
2771  * get_format call.
2772  * - It is perfectly possible to call this function without actually using
2773  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
2774  * previously initialized AVHWFramesContext, and calling this API function
2775  * only to test whether the required frame parameters have changed.
2776  * - Fields that use dynamically allocated values of any kind must not be set
2777  * by the user unless setting them is explicitly allowed by the documentation.
2778  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
2779  * the new free callback must call the potentially set previous free callback.
2780  * This API call may set any dynamically allocated fields, including the free
2781  * callback.
2782  *
2783  * The function will set at least the following fields on AVHWFramesContext
2784  * (potentially more, depending on hwaccel API):
2785  *
2786  * - All fields set by av_hwframe_ctx_alloc().
2787  * - Set the format field to hw_pix_fmt.
2788  * - Set the sw_format field to the most suited and most versatile format. (An
2789  * implication is that this will prefer generic formats over opaque formats
2790  * with arbitrary restrictions, if possible.)
2791  * - Set the width/height fields to the coded frame size, rounded up to the
2792  * API-specific minimum alignment.
2793  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
2794  * field to the number of maximum reference surfaces possible with the codec,
2795  * plus 1 surface for the user to work (meaning the user can safely reference
2796  * at most 1 decoded surface at a time), plus additional buffering introduced
2797  * by frame threading. If the hwaccel does not require pre-allocation, the
2798  * field is left to 0, and the decoder will allocate new surfaces on demand
2799  * during decoding.
2800  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
2801  * hardware API.
2802  *
2803  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
2804  * with basic frame parameters set.
2805  *
2806  * The function is stateless, and does not change the AVCodecContext or the
2807  * device_ref AVHWDeviceContext.
2808  *
2809  * @param avctx The context which is currently calling get_format, and which
2810  * implicitly contains all state needed for filling the returned
2811  * AVHWFramesContext properly.
2812  * @param device_ref A reference to the AVHWDeviceContext describing the device
2813  * which will be used by the hardware decoder.
2814  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
2815  * @param out_frames_ref On success, set to a reference to an _uninitialized_
2816  * AVHWFramesContext, created from the given device_ref.
2817  * Fields will be set to values required for decoding.
2818  * Not changed if an error is returned.
2819  * @return zero on success, a negative value on error. The following error codes
2820  * have special semantics:
2821  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
2822  * is always manual, or it is a decoder which does not
2823  * support setting AVCodecContext.hw_frames_ctx at all,
2824  * or it is a software format.
2825  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
2826  * this configuration, or the device_ref is not supported
2827  * for the hwaccel referenced by hw_pix_fmt.
2828  */
2830  AVBufferRef *device_ref,
2832  AVBufferRef **out_frames_ref);
2833 
2834 
2835 
2836 /**
2837  * @defgroup lavc_parsing Frame parsing
2838  * @{
2839  */
2840 
2843  AV_PICTURE_STRUCTURE_TOP_FIELD, ///< coded as top field
2844  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, ///< coded as bottom field
2845  AV_PICTURE_STRUCTURE_FRAME, ///< coded as frame
2846 };
2847 
2848 typedef struct AVCodecParserContext {
2849  void *priv_data;
2850  const struct AVCodecParser *parser;
2851  int64_t frame_offset; /* offset of the current frame */
2852  int64_t cur_offset; /* current offset
2853  (incremented by each av_parser_parse()) */
2854  int64_t next_frame_offset; /* offset of the next frame */
2855  /* video info */
2856  int pict_type; /* XXX: Put it back in AVCodecContext. */
2857  /**
2858  * This field is used for proper frame duration computation in lavf.
2859  * It signals, how much longer the frame duration of the current frame
2860  * is compared to normal frame duration.
2861  *
2862  * frame_duration = (1 + repeat_pict) * time_base
2863  *
2864  * It is used by codecs like H.264 to display telecined material.
2865  */
2866  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
2867  int64_t pts; /* pts of the current frame */
2868  int64_t dts; /* dts of the current frame */
2869 
2870  /* private data */
2871  int64_t last_pts;
2872  int64_t last_dts;
2874 
2875 #define AV_PARSER_PTS_NB 4
2880 
2881  int flags;
2882 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
2883 #define PARSER_FLAG_ONCE 0x0002
2884 /// Set if the parser has a valid file offset
2885 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
2886 #define PARSER_FLAG_USE_CODEC_TS 0x1000
2887 
2888  int64_t offset; ///< byte offset from starting packet start
2890 
2891  /**
2892  * Set by parser to 1 for key frames and 0 for non-key frames.
2893  * It is initialized to -1, so if the parser doesn't set this flag,
2894  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
2895  * will be used.
2896  */
2898 
2899  // Timestamp generation support:
2900  /**
2901  * Synchronization point for start of timestamp generation.
2902  *
2903  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
2904  * (default).
2905  *
2906  * For example, this corresponds to presence of H.264 buffering period
2907  * SEI message.
2908  */
2910 
2911  /**
2912  * Offset of the current timestamp against last timestamp sync point in
2913  * units of AVCodecContext.time_base.
2914  *
2915  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2916  * contain a valid timestamp offset.
2917  *
2918  * Note that the timestamp of sync point has usually a nonzero
2919  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
2920  * the next frame after timestamp sync point will be usually 1.
2921  *
2922  * For example, this corresponds to H.264 cpb_removal_delay.
2923  */
2925 
2926  /**
2927  * Presentation delay of current frame in units of AVCodecContext.time_base.
2928  *
2929  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2930  * contain valid non-negative timestamp delta (presentation time of a frame
2931  * must not lie in the past).
2932  *
2933  * This delay represents the difference between decoding and presentation
2934  * time of the frame.
2935  *
2936  * For example, this corresponds to H.264 dpb_output_delay.
2937  */
2939 
2940  /**
2941  * Position of the packet in file.
2942  *
2943  * Analogous to cur_frame_pts/dts
2944  */
2946 
2947  /**
2948  * Byte position of currently parsed frame in stream.
2949  */
2950  int64_t pos;
2951 
2952  /**
2953  * Previous frame byte position.
2954  */
2955  int64_t last_pos;
2956 
2957  /**
2958  * Duration of the current frame.
2959  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
2960  * For all other types, this is in units of AVCodecContext.time_base.
2961  */
2963 
2965 
2966  /**
2967  * Indicate whether a picture is coded as a frame, top field or bottom field.
2968  *
2969  * For example, H.264 field_pic_flag equal to 0 corresponds to
2970  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
2971  * equal to 1 and bottom_field_flag equal to 0 corresponds to
2972  * AV_PICTURE_STRUCTURE_TOP_FIELD.
2973  */
2975 
2976  /**
2977  * Picture number incremented in presentation or output order.
2978  * This field may be reinitialized at the first picture of a new sequence.
2979  *
2980  * For example, this corresponds to H.264 PicOrderCnt.
2981  */
2983 
2984  /**
2985  * Dimensions of the decoded video intended for presentation.
2986  */
2987  int width;
2988  int height;
2989 
2990  /**
2991  * Dimensions of the coded video.
2992  */
2995 
2996  /**
2997  * The format of the coded data, corresponds to enum AVPixelFormat for video
2998  * and for enum AVSampleFormat for audio.
2999  *
3000  * Note that a decoder can have considerable freedom in how exactly it
3001  * decodes the data, so the format reported here might be different from the
3002  * one returned by a decoder.
3003  */
3004  int format;
3006 
3007 typedef struct AVCodecParser {
3008  int codec_ids[7]; /* several codec IDs are permitted */
3011  /* This callback never returns an error, a negative value means that
3012  * the frame start was in a previous packet. */
3014  AVCodecContext *avctx,
3015  const uint8_t **poutbuf, int *poutbuf_size,
3016  const uint8_t *buf, int buf_size);
3018  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
3019 } AVCodecParser;
3020 
3021 /**
3022  * Iterate over all registered codec parsers.
3023  *
3024  * @param opaque a pointer where libavcodec will store the iteration state. Must
3025  * point to NULL to start the iteration.
3026  *
3027  * @return the next registered codec parser or NULL when the iteration is
3028  * finished
3029  */
3030 const AVCodecParser *av_parser_iterate(void **opaque);
3031 
3033 
3034 /**
3035  * Parse a packet.
3036  *
3037  * @param s parser context.
3038  * @param avctx codec context.
3039  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
3040  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
3041  * @param buf input buffer.
3042  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
3043  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
3044  To signal EOF, this should be 0 (so that the last frame
3045  can be output).
3046  * @param pts input presentation timestamp.
3047  * @param dts input decoding timestamp.
3048  * @param pos input byte position in stream.
3049  * @return the number of bytes of the input bitstream used.
3050  *
3051  * Example:
3052  * @code
3053  * while(in_len){
3054  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
3055  * in_data, in_len,
3056  * pts, dts, pos);
3057  * in_data += len;
3058  * in_len -= len;
3059  *
3060  * if(size)
3061  * decode_frame(data, size);
3062  * }
3063  * @endcode
3064  */
3066  AVCodecContext *avctx,
3067  uint8_t **poutbuf, int *poutbuf_size,
3068  const uint8_t *buf, int buf_size,
3069  int64_t pts, int64_t dts,
3070  int64_t pos);
3071 
3073 
3074 /**
3075  * @}
3076  * @}
3077  */
3078 
3079 /**
3080  * @addtogroup lavc_encoding
3081  * @{
3082  */
3083 
3084 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3085  const AVSubtitle *sub);
3086 
3087 
3088 /**
3089  * @}
3090  */
3091 
3092 /**
3093  * @defgroup lavc_misc Utility functions
3094  * @ingroup libavc
3095  *
3096  * Miscellaneous utility functions related to both encoding and decoding
3097  * (or neither).
3098  * @{
3099  */
3100 
3101 /**
3102  * @defgroup lavc_misc_pixfmt Pixel formats
3103  *
3104  * Functions for working with pixel formats.
3105  * @{
3106  */
3107 
3108 /**
3109  * Return a value representing the fourCC code associated to the
3110  * pixel format pix_fmt, or 0 if no associated fourCC code can be
3111  * found.
3112  */
3114 
3115 /**
3116  * Find the best pixel format to convert to given a certain source pixel
3117  * format. When converting from one pixel format to another, information loss
3118  * may occur. For example, when converting from RGB24 to GRAY, the color
3119  * information will be lost. Similarly, other losses occur when converting from
3120  * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
3121  * the given pixel formats should be used to suffer the least amount of loss.
3122  * The pixel formats from which it chooses one, are determined by the
3123  * pix_fmt_list parameter.
3124  *
3125  *
3126  * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
3127  * @param[in] src_pix_fmt source pixel format
3128  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
3129  * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
3130  * @return The best pixel format to convert to or -1 if none was found.
3131  */
3132 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
3133  enum AVPixelFormat src_pix_fmt,
3134  int has_alpha, int *loss_ptr);
3135 
3137 
3138 /**
3139  * @}
3140  */
3141 
3142 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
3143 
3144 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
3145 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
3146 //FIXME func typedef
3147 
3148 /**
3149  * Fill AVFrame audio data and linesize pointers.
3150  *
3151  * The buffer buf must be a preallocated buffer with a size big enough
3152  * to contain the specified samples amount. The filled AVFrame data
3153  * pointers will point to this buffer.
3154  *
3155  * AVFrame extended_data channel pointers are allocated if necessary for
3156  * planar audio.
3157  *
3158  * @param frame the AVFrame
3159  * frame->nb_samples must be set prior to calling the
3160  * function. This function fills in frame->data,
3161  * frame->extended_data, frame->linesize[0].
3162  * @param nb_channels channel count
3163  * @param sample_fmt sample format
3164  * @param buf buffer to use for frame data
3165  * @param buf_size size of buffer
3166  * @param align plane size sample alignment (0 = default)
3167  * @return >=0 on success, negative error code on failure
3168  * @todo return the size in bytes required to store the samples in
3169  * case of success, at the next libavutil bump
3170  */
3171 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
3172  enum AVSampleFormat sample_fmt, const uint8_t *buf,
3173  int buf_size, int align);
3174 
3175 /**
3176  * Reset the internal codec state / flush internal buffers. Should be called
3177  * e.g. when seeking or when switching to a different stream.
3178  *
3179  * @note for decoders, this function just releases any references the decoder
3180  * might keep internally, but the caller's references remain valid.
3181  *
3182  * @note for encoders, this function will only do something if the encoder
3183  * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3184  * will drain any remaining packets, and can then be re-used for a different
3185  * stream (as opposed to sending a null frame which will leave the encoder
3186  * in a permanent EOF state after draining). This can be desirable if the
3187  * cost of tearing down and replacing the encoder instance is high.
3188  */
3190 
3191 /**
3192  * Return audio frame duration.
3193  *
3194  * @param avctx codec context
3195  * @param frame_bytes size of the frame, or 0 if unknown
3196  * @return frame duration, in samples, if known. 0 if not able to
3197  * determine.
3198  */
3199 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
3200 
3201 /* memory */
3202 
3203 /**
3204  * Same behaviour av_fast_malloc but the buffer has additional
3205  * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
3206  *
3207  * In addition the whole buffer will initially and after resizes
3208  * be 0-initialized so that no uninitialized data will ever appear.
3209  */
3210 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
3211 
3212 /**
3213  * Same behaviour av_fast_padded_malloc except that buffer will always
3214  * be 0-initialized after call.
3215  */
3216 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
3217 
3218 /**
3219  * @return a positive value if s is open (i.e. avcodec_open2() was called on it
3220  * with no corresponding avcodec_close()), 0 otherwise.
3221  */
3223 
3224 /**
3225  * @}
3226  */
3227 
3228 #endif /* AVCODEC_AVCODEC_H */
AVSubtitle
Definition: avcodec.h:2357
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:431
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:164
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1068
AVCodecContext::hwaccel
const struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:1402
AVCodec
AVCodec.
Definition: codec.h:204
AVCodecContext::hwaccel_context
void * hwaccel_context
Legacy hardware accelerator context.
Definition: avcodec.h:1426
hw_pix_fmt
static enum AVPixelFormat hw_pix_fmt
Definition: hw_decode.c:46
avcodec_enum_to_chroma_pos
attribute_deprecated int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos)
Converts AVChromaLocation to swscale x/y chroma position.
Definition: utils.c:359
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVCodecParserContext::pts
int64_t pts
Definition: avcodec.h:2867
AVCodecContext::log_level_offset
int log_level_offset
Definition: avcodec.h:437
AVCodecContext::keyint_min
int keyint_min
minimum GOP size
Definition: avcodec.h:973
avcodec_receive_packet
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:512
AVCodecContext::workaround_bugs
int workaround_bugs
Work around bugs in encoders which sometimes cannot be detected automatically.
Definition: avcodec.h:1313
AVSubtitle::rects
AVSubtitleRect ** rects
Definition: avcodec.h:2362
AVCodecContext::get_format
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Callback to negotiate the pixel format.
Definition: avcodec.h:695
AVCodecParserContext::dts_sync_point
int dts_sync_point
Synchronization point for start of timestamp generation.
Definition: avcodec.h:2909
AVCodecContext::audio_service_type
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:1119
AVCodecContext::colorspace
enum AVColorSpace colorspace
YUV colorspace type.
Definition: avcodec.h:1008
AVColorTransferCharacteristic
AVColorTransferCharacteristic
Color Transfer Characteristic.
Definition: pixfmt.h:558
AVCodecContext::av_class
const AVClass * av_class
information on struct for av_log
Definition: avcodec.h:436
AVCodecParserContext::pict_type
int pict_type
Definition: avcodec.h:2856
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1040
AVCodecContext::rc_min_rate
int64_t rc_min_rate
minimum bitrate
Definition: avcodec.h:1263
AVCodecParserContext::output_picture_number
int output_picture_number
Picture number incremented in presentation or output order.
Definition: avcodec.h:2982
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:54
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:2116
AV_PICTURE_STRUCTURE_UNKNOWN
@ AV_PICTURE_STRUCTURE_UNKNOWN
unknown
Definition: avcodec.h:2842
AVHWAccel::caps_internal
int caps_internal
Internal hwaccel capabilities.
Definition: avcodec.h:2240
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:99
AVCodecParserContext::duration
int duration
Duration of the current frame.
Definition: avcodec.h:2962
AVCodecContext::err_recognition
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1384
avcodec_string
void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
Definition: avcodec.c:505
rational.h
AVCodecContext::coded_side_data
AVPacketSideData * coded_side_data
Additional data associated with the entire coded stream.
Definition: avcodec.h:1891
AVSubtitleRect
Definition: avcodec.h:2329
AVSubtitle::num_rects
unsigned num_rects
Definition: avcodec.h:2361
av_parser_iterate
const AVCodecParser * av_parser_iterate(void **opaque)
Iterate over all registered codec parsers.
Definition: parsers.c:84
AVCodecContext::intra_matrix
uint16_t * intra_matrix
custom intra quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:916
AVCodecContext::mv0_threshold
int mv0_threshold
Note: Value depends upon the compare function used for fullpel ME.
Definition: avcodec.h:987
AVCodecContext::lumi_masking
float lumi_masking
luminance masking (0-> disabled)
Definition: avcodec.h:750
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:330
AVCodecContext::color_trc
enum AVColorTransferCharacteristic color_trc
Color Transfer Characteristic.
Definition: avcodec.h:1001
AVPacketSideData
Definition: packet.h:315
AVCodecParserContext::pts_dts_delta
int pts_dts_delta
Presentation delay of current frame in units of AVCodecContext.time_base.
Definition: avcodec.h:2938
AVCodecContext::slice_offset
int * slice_offset
slice offsets in the frame in bytes
Definition: avcodec.h:792
avcodec_decode_subtitle2
int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub, int *got_sub_ptr, AVPacket *avpkt)
Decode a subtitle message.
Definition: decode.c:863
AVCodecContext::field_order
enum AVFieldOrder field_order
Field order.
Definition: avcodec.h:1037
AVHWAccel::capabilities
int capabilities
Hardware accelerated codec capabilities.
Definition: avcodec.h:2136
version_major.h
AVCodecContext::b_quant_offset
float b_quant_offset
qscale offset between IP and B-frames
Definition: avcodec.h:719
AVCodecParserContext::height
int height
Definition: avcodec.h:2988
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:344
RcOverride::qscale
int qscale
Definition: avcodec.h:199
AVHWAccel::init
int(* init)(AVCodecContext *avctx)
Initialize the hwaccel private data.
Definition: avcodec.h:2221
AVCodecContext::subtitle_header
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:1741
AVSubtitleRect::linesize
int linesize[4]
Definition: avcodec.h:2341
AVCodecParserContext::cur_frame_start_index
int cur_frame_start_index
Definition: avcodec.h:2876
AVCodecContext::me_pre_cmp
int me_pre_cmp
motion estimation prepass comparison function
Definition: avcodec.h:864
AVDictionary
Definition: dict.c:32
AVColorPrimaries
AVColorPrimaries
Chromaticity coordinates of the source primaries.
Definition: pixfmt.h:533
avcodec_default_get_format
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: decode.c:935
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:904
avcodec_is_open
int avcodec_is_open(AVCodecContext *s)
Definition: avcodec.c:704
AVCodecContext::qmax
int qmax
maximum quantizer
Definition: avcodec.h:1227
AVCodecParserContext::coded_width
int coded_width
Dimensions of the coded video.
Definition: avcodec.h:2993
AVCodecContext::delay
int delay
Codec delay.
Definition: avcodec.h:587
AVCodecContext::me_subpel_quality
int me_subpel_quality
subpel ME quality
Definition: avcodec.h:878
AVCodecContext::mb_cmp
int mb_cmp
macroblock comparison function (not supported yet)
Definition: avcodec.h:820
AVCodecContext::slice_count
int slice_count
slice count
Definition: avcodec.h:785
AVPictureStructure
AVPictureStructure
Definition: avcodec.h:2841
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:306
SUBTITLE_ASS
@ SUBTITLE_ASS
Formatted text, the ass field must be set by the decoder and is authoritative.
Definition: avcodec.h:2324
AVCodecParserContext::parser
const struct AVCodecParser * parser
Definition: avcodec.h:2850
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:1768
AVCodecContext::skip_top
int skip_top
Number of macroblock rows at the top which are skipped.
Definition: avcodec.h:939
AVCodecParserContext::offset
int64_t offset
byte offset from starting packet start
Definition: avcodec.h:2888
AVHWAccel
Definition: avcodec.h:2103
AVCodecParserContext::key_frame
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:2897
avcodec_chroma_pos_to_enum
attribute_deprecated enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos)
Converts swscale x/y chroma position to AVChromaLocation.
Definition: utils.c:364
AVCodecContext::skip_idct
enum AVDiscard skip_idct
Skip IDCT/dequantization for selected frames.
Definition: avcodec.h:1724
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:736
AVCodecContext::nsse_weight
int nsse_weight
noise vs.
Definition: avcodec.h:1576
AVCodecContext::codec
const struct AVCodec * codec
Definition: avcodec.h:440
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:2092
AVCodecContext::skip_frame
enum AVDiscard skip_frame
Skip decoding for selected frames.
Definition: avcodec.h:1731
AVCodecContext::thread_count
int thread_count
thread count is used to decide how many independent tasks should be passed to execute()
Definition: avcodec.h:1499
samplefmt.h
AVSubtitleRect::x
int x
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2330
AVCodecContext::initial_padding
int initial_padding
Audio only.
Definition: avcodec.h:1759
AVCodecContext::refs
int refs
number of reference frames
Definition: avcodec.h:980
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:511
AVCodecContext::bit_rate_tolerance
int bit_rate_tolerance
number of bits the bitstream is allowed to diverge from the reference.
Definition: avcodec.h:489
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:1440
av_parser_init
AVCodecParserContext * av_parser_init(int codec_id)
Definition: parser.c:32
pts
static int64_t pts
Definition: transcode_aac.c:654
AVCodecContext::coded_height
int coded_height
Definition: avcodec.h:619
AVCodecContext::max_samples
int64_t max_samples
The number of samples per frame to maximally accept.
Definition: avcodec.h:2032
codec.h
AVCodecParserContext::dts
int64_t dts
Definition: avcodec.h:2868
AVSubtitleRect::ass
char * ass
0 terminated ASS/SSA compatible event line.
Definition: avcodec.h:2352
AVHWAccel::priv_data_size
int priv_data_size
Size of the private data to allocate in AVCodecInternal.hwaccel_priv_data.
Definition: avcodec.h:2235
avsubtitle_free
void avsubtitle_free(AVSubtitle *sub)
Free all allocated data in the given subtitle struct.
Definition: avcodec.c:409
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:1209
AV_PICTURE_STRUCTURE_FRAME
@ AV_PICTURE_STRUCTURE_FRAME
coded as frame
Definition: avcodec.h:2845
RcOverride::quality_factor
float quality_factor
Definition: avcodec.h:200
AVCodecContext::color_primaries
enum AVColorPrimaries color_primaries
Chromaticity coordinates of the source primaries.
Definition: avcodec.h:994
AVCodecParserContext::cur_frame_end
int64_t cur_frame_end[AV_PARSER_PTS_NB]
Definition: avcodec.h:2889
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:1796
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:1284
codec_id.h
AVHWAccel::alloc_frame
int(* alloc_frame)(AVCodecContext *avctx, AVFrame *frame)
Allocate a custom buffer.
Definition: avcodec.h:2149
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:533
AVCodecContext::has_b_frames
int has_b_frames
Size of the frame reordering buffer in the decoder.
Definition: avcodec.h:727
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:149
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:256
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:1306
AVCodecContext::global_quality
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:497
AVCodecParserContext::fetch_timestamp
int fetch_timestamp
Definition: avcodec.h:2873
AVFieldOrder
AVFieldOrder
Definition: codec_par.h:38
AVHWAccel::uninit
int(* uninit)(AVCodecContext *avctx)
Uninitialize the hwaccel private data.
Definition: avcodec.h:2229
RcOverride
Definition: avcodec.h:196
AVCodecParserContext::last_pts
int64_t last_pts
Definition: avcodec.h:2871
AVSubtitleRect::y
int y
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2331
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:563
AVCodecContext::error_concealment
int error_concealment
error concealment flags
Definition: avcodec.h:1350
avcodec_receive_frame
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder or encoder (when the AV_CODEC_FLAG_RECON_FRAME flag is used...
Definition: avcodec.c:709
AVSubtitleType
AVSubtitleType
Definition: avcodec.h:2309
AVCodecContext::thread_type
int thread_type
Which multithreading methods to use.
Definition: avcodec.h:1509
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1484
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:370
RcOverride::start_frame
int start_frame
Definition: avcodec.h:197
channels
channels
Definition: aptx.h:31
AVCodecParserContext::format
int format
The format of the coded data, corresponds to enum AVPixelFormat for video and for enum AVSampleFormat...
Definition: avcodec.h:3004
AVSubtitle::pts
int64_t pts
Same as packet pts, in AV_TIME_BASE.
Definition: avcodec.h:2363
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:141
AVCodecContext::max_pixels
int64_t max_pixels
The number of pixels per image to maximally accept.
Definition: avcodec.h:1944
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:388
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:2179
AVCodecContext::rc_max_rate
int64_t rc_max_rate
maximum bitrate
Definition: avcodec.h:1256
AVCodecContext::error
uint64_t error[AV_NUM_DATA_POINTERS]
error
Definition: avcodec.h:1433
AVSubtitleRect::text
char * text
0 terminated plain UTF-8 text
Definition: avcodec.h:2345
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:441
AVCodecContext::p_masking
float p_masking
p block masking (0-> disabled)
Definition: avcodec.h:771
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:2924
AVCodecParserContext::repeat_pict
int repeat_pict
This field is used for proper frame duration computation in lavf.
Definition: avcodec.h:2866
AV_PICTURE_STRUCTURE_BOTTOM_FIELD
@ AV_PICTURE_STRUCTURE_BOTTOM_FIELD
coded as bottom field
Definition: avcodec.h:2844
AVCodecContext::rc_buffer_size
int rc_buffer_size
decoder bitstream buffer size
Definition: avcodec.h:1241
AVCodecContext::sub_charenc
char * sub_charenc
DTS of the last frame.
Definition: avcodec.h:1806
AVSubtitleRect::w
int w
width of pict, undefined when pict is not set
Definition: avcodec.h:2332
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:183
AVCodecContext::apply_cropping
int apply_cropping
Video decoding only.
Definition: avcodec.h:2002
AVCodecContext::color_range
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:1015
AVCodecContext::slice_flags
int slice_flags
slice flags
Definition: avcodec.h:894
AVCodecParser::parser_close
void(* parser_close)(AVCodecParserContext *s)
Definition: avcodec.h:3017
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:164
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:1892
AVCodecContext::qblur
float qblur
amount of qscale smoothing over time (0.0-1.0)
Definition: avcodec.h:1213
AV_PICTURE_STRUCTURE_TOP_FIELD
@ AV_PICTURE_STRUCTURE_TOP_FIELD
coded as top field
Definition: avcodec.h:2843
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:481
AVCodecParser::split
int(* split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
Definition: avcodec.h:3018
AVHWAccel::end_frame
int(* end_frame)(AVCodecContext *avctx)
Called at the end of each frame or field picture.
Definition: avcodec.h:2203
AVCodecContext::subtitle_header_size
int subtitle_header_size
Definition: avcodec.h:1742
AVSubtitleRect::data
uint8_t * data[4]
data+linesize for the bitmap of this subtitle.
Definition: avcodec.h:2340
AVCodecContext::trailing_padding
int trailing_padding
Audio only.
Definition: avcodec.h:1936
AVCodecContext::ildct_cmp
int ildct_cmp
interlaced DCT comparison function
Definition: avcodec.h:826
avcodec_license
const char * avcodec_license(void)
Return the libavcodec license.
Definition: version.c:46
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:1538
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:1277
avcodec_open2
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:115
AVCodecParserContext::flags
int flags
Definition: avcodec.h:2881
avcodec_version
unsigned avcodec_version(void)
Return the LIBAVCODEC_VERSION_INT constant.
Definition: version.c:31
AVCodecContext::me_cmp
int me_cmp
motion estimation comparison function
Definition: avcodec.h:808
AVCodecParserContext::picture_structure
enum AVPictureStructure picture_structure
Indicate whether a picture is coded as a frame, top field or bottom field.
Definition: avcodec.h:2974
AVCodecContext::trellis
int trellis
trellis RD quantization
Definition: avcodec.h:1291
AVCodecContext::level
int level
level
Definition: avcodec.h:1709
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:79
avcodec_get_subtitle_rect_class
const AVClass * avcodec_get_subtitle_rect_class(void)
Get the AVClass for AVSubtitleRect.
Definition: options.c:241
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:49
AVCodecContext::temporal_cplx_masking
float temporal_cplx_masking
temporary complexity masking (0-> disabled)
Definition: avcodec.h:757
AVCodecContext::qcompress
float qcompress
amount of qscale change between easy & hard scenes (0.0-1.0)
Definition: avcodec.h:1212
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:554
AVCodecContext::lowres
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:1491
options
const OptionDef options[]
AVCodecContext::stats_out
char * stats_out
pass1 encoding statistics output buffer
Definition: avcodec.h:1298
AVCodecContext::rc_override
RcOverride * rc_override
Definition: avcodec.h:1249
AVCodecContext::flags2
int flags2
AV_CODEC_FLAG2_*.
Definition: avcodec.h:518
AVMediaType
AVMediaType
Definition: avutil.h:199
AVCodecParserContext::frame_offset
int64_t frame_offset
Definition: avcodec.h:2851
AVCodecContext::gop_size
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:626
AVCodecParser::codec_ids
int codec_ids[7]
Definition: avcodec.h:3008
AVCodecContext::extra_hw_frames
int extra_hw_frames
Definition: avcodec.h:2016
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:301
AVCodecParserContext::next_frame_offset
int64_t next_frame_offset
Definition: avcodec.h:2854
AVCodecParserContext::cur_frame_offset
int64_t cur_frame_offset[AV_PARSER_PTS_NB]
Definition: avcodec.h:2877
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1056
AVCodecContext::pkt_timebase
AVRational pkt_timebase
Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
Definition: avcodec.h:1782
size
int size
Definition: twinvq_data.h:10344
AVCodecParserContext::width
int width
Dimensions of the decoded video intended for presentation.
Definition: avcodec.h:2987
AV_NUM_DATA_POINTERS
#define AV_NUM_DATA_POINTERS
Definition: frame.h:331
avcodec_get_frame_class
const attribute_deprecated AVClass * avcodec_get_frame_class(void)
Definition: options.c:214
AVCodecContext::me_range
int me_range
maximum motion estimation search range in subpel units If 0 then no limit.
Definition: avcodec.h:887
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:3013
AVCodecContext::skip_alpha
int skip_alpha
Skip processing alpha if supported by codec.
Definition: avcodec.h:1832
AVCodecContext::chroma_intra_matrix
uint16_t * chroma_intra_matrix
custom intra quantization matrix
Definition: avcodec.h:1857
AVCodecContext::skip_bottom
int skip_bottom
Number of macroblock rows at the bottom which are skipped.
Definition: avcodec.h:946
AVCodecContext::last_predictor_count
int last_predictor_count
amount of previous MV predictors (2a+1 x 2a+1 square)
Definition: avcodec.h:857
AVSubtitle::end_display_time
uint32_t end_display_time
Definition: avcodec.h:2360
frame.h
AVSubtitleRect::type
enum AVSubtitleType type
Definition: avcodec.h:2343
SUBTITLE_TEXT
@ SUBTITLE_TEXT
Plain text, the text field must be set by the decoder and is authoritative.
Definition: avcodec.h:2318
buffer.h
align
static const uint8_t *BS_FUNC() align(BSCTX *bc)
Skip bits to a byte boundary.
Definition: bitstream_template.h:411
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
SUBTITLE_NONE
@ SUBTITLE_NONE
Definition: avcodec.h:2310
encode
static void encode(AVCodecContext *ctx, AVFrame *frame, AVPacket *pkt, FILE *output)
Definition: encode_audio.c:94
AVCodecContext::me_sub_cmp
int me_sub_cmp
subpixel motion estimation comparison function
Definition: avcodec.h:814
AVCodecContext::pts_correction_num_faulty_dts
int64_t pts_correction_num_faulty_dts
Number of incorrect PTS values so far.
Definition: avcodec.h:1797
height
#define height
AVCodecContext::pts_correction_last_pts
int64_t pts_correction_last_pts
Number of incorrect DTS values so far.
Definition: avcodec.h:1798
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:45
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:1127
attributes.h
AVCodecInternal
Definition: internal.h:52
AVCodecContext::skip_loop_filter
enum AVDiscard skip_loop_filter
Skip loop filtering for selected frames.
Definition: avcodec.h:1717
SUBTITLE_BITMAP
@ SUBTITLE_BITMAP
A bitmap, pict will be set.
Definition: avcodec.h:2312
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:712
AVCodecParserContext::cur_frame_pts
int64_t cur_frame_pts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2878
AVChromaLocation
AVChromaLocation
Location of chroma samples.
Definition: pixfmt.h:680
AVCodecParserContext::cur_frame_pos
int64_t cur_frame_pos[AV_PARSER_PTS_NB]
Position of the packet in file.
Definition: avcodec.h:2945
AVHWAccel::name
const char * name
Name of the hardware accelerated codec.
Definition: avcodec.h:2109
AVSubtitleRect::flags
int flags
Definition: avcodec.h:2354
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1477
avcodec_default_get_buffer2
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags)
The default callback for AVCodecContext.get_buffer2().
Definition: get_buffer.c:282
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:607
AVCodecParserContext::pos
int64_t pos
Byte position of currently parsed frame in stream.
Definition: avcodec.h:2950
AVSubtitle::format
uint16_t format
Definition: avcodec.h:2358
log.h
RcOverride::end_frame
int end_frame
Definition: avcodec.h:198
AVCodecContext::properties
unsigned properties
Properties of the stream that gets decoded.
Definition: avcodec.h:1880
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:532
AVSubtitleRect::nb_colors
int nb_colors
number of colors in pict, undefined when pict is not set
Definition: avcodec.h:2334
AVHWAccel::decode_slice
int(* decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size)
Callback for each slice.
Definition: avcodec.h:2192
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:182
AVCodecContext::intra_dc_precision
int intra_dc_precision
precision of the intra DC coefficient - 8
Definition: avcodec.h:932
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:587
AVCodecContext::cutoff
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1092
AVCodecContext::hwaccel_flags
int hwaccel_flags
Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated decoding (if active).
Definition: avcodec.h:1975
AVCodecParserContext::cur_offset
int64_t cur_offset
Definition: avcodec.h:2852
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
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:49
AVCodecParser::parser_init
int(* parser_init)(AVCodecParserContext *s)
Definition: avcodec.h:3010
AVCodecContext::pts_correction_last_dts
int64_t pts_correction_last_dts
PTS of the last frame.
Definition: avcodec.h:1799
AVCodecContext::dia_size
int dia_size
ME diamond size & shape.
Definition: avcodec.h:850
AVCodecContext::dump_separator
uint8_t * dump_separator
dump format separator.
Definition: avcodec.h:1865
AVCodecContext::mb_lmin
int mb_lmin
minimum MB Lagrange multiplier
Definition: avcodec.h:953
av_get_audio_frame_duration
int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
Return audio frame duration.
Definition: utils.c:812
AVCodecContext::idct_algo
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:1453
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:1966
AVCodecContext::chroma_sample_location
enum AVChromaLocation chroma_sample_location
This defines the location of chroma samples.
Definition: avcodec.h:1022
AVCodecContext::height
int height
Definition: avcodec.h:604
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:479
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:641
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:1916
AVCodecParserContext
Definition: avcodec.h:2848
AVCodecContext::sub_charenc_mode
int sub_charenc_mode
Subtitles character encoding mode.
Definition: avcodec.h:1814
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:1049
ret
ret
Definition: filter_design.txt:187
AVSubtitleRect::h
int h
height of pict, undefined when pict is not set
Definition: avcodec.h:2333
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:1085
pixfmt.h
avcodec_flush_buffers
void avcodec_flush_buffers(AVCodecContext *avctx)
Reset the internal codec state / flush internal buffers.
Definition: avcodec.c:369
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:1923
AVCodecParserContext::coded_height
int coded_height
Definition: avcodec.h:2994
AVCodecContext::strict_std_compliance
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1343
AVCodecContext::opaque
void * opaque
Private data of the user, can be used to carry app specific stuff.
Definition: avcodec.h:473
pos
unsigned int pos
Definition: spdifenc.c:412
AVCodecParser::priv_data_size
int priv_data_size
Definition: avcodec.h:3009
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:666
AVCodecContext::max_qdiff
int max_qdiff
maximum quantizer difference between frames
Definition: avcodec.h:1234
AVCodecContext::dark_masking
float dark_masking
darkness masking (0-> disabled)
Definition: avcodec.h:778
AVCodecContext
main external API structure.
Definition: avcodec.h:431
AVCodecContext::active_thread_type
int active_thread_type
Which multithreading methods are in use by the codec.
Definition: avcodec.h:1518
AVCodecContext::codec_descriptor
const AVCodecDescriptor * codec_descriptor
AVCodecDescriptor.
Definition: avcodec.h:1789
c2
static const uint64_t c2
Definition: murmur3.c:52
AVCodecParserContext::field_order
enum AVFieldOrder field_order
Definition: avcodec.h:2964
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:1550
AVCodecContext::qmin
int qmin
minimum quantizer
Definition: avcodec.h:1220
AVHWAccel::frame_priv_data_size
int frame_priv_data_size
Size of per-frame hardware accelerator private data.
Definition: avcodec.h:2212
AVCodecContext::bidir_refine
int bidir_refine
Definition: avcodec.h:966
AVCodecContext::profile
int profile
profile
Definition: avcodec.h:1583
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:62
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:2084
AVCodecContext::spatial_cplx_masking
float spatial_cplx_masking
spatial complexity masking (0-> disabled)
Definition: avcodec.h:764
AVCodecContext::i_quant_offset
float i_quant_offset
qscale offset between P and I-frames
Definition: avcodec.h:743
AVCodecContext::discard_damaged_percentage
int discard_damaged_percentage
The percentage of damaged samples to discard a frame.
Definition: avcodec.h:2024
AVCodecContext::mb_lmax
int mb_lmax
maximum MB Lagrange multiplier
Definition: avcodec.h:960
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:2042
AVCodecContext::pre_dia_size
int pre_dia_size
ME prepass diamond size & shape.
Definition: avcodec.h:871
AVCodecContext::debug
int debug
debug
Definition: avcodec.h:1360
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:2165
AVCodecContext::coded_width
int coded_width
Bitstream width / height, may be different from width/height e.g.
Definition: avcodec.h:619
AVCodecContext::codec_type
enum AVMediaType codec_type
Definition: avcodec.h:439
AVCodecContext::seek_preroll
int seek_preroll
Number of samples to skip after a discontinuity.
Definition: avcodec.h:1839
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:115
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:703
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:1079
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:1270
AVCodecContext::codec_tag
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:456
codec_par.h
AV_PARSER_PTS_NB
#define AV_PARSER_PTS_NB
Definition: avcodec.h:2875
AVCodecContext::slices
int slices
Number of slices.
Definition: avcodec.h:1031
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:458
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:57
AVCodecParserContext::last_pos
int64_t last_pos
Previous frame byte position.
Definition: avcodec.h:2955
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
AVCodecContext::inter_matrix
uint16_t * inter_matrix
custom inter quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:925
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:2250
AVCodecParser
Definition: avcodec.h:3007
AVCodecContext::rc_override_count
int rc_override_count
ratecontrol override, see RcOverride
Definition: avcodec.h:1248
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:1395
avcodec_configuration
const char * avcodec_configuration(void)
Return the libavcodec build-time configuration.
Definition: version.c:41
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:604
AVCodecContext::debug_mv
attribute_deprecated int debug_mv
Definition: avcodec.h:1846
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParserContext::priv_data
void * priv_data
Definition: avcodec.h:2849
AVCodecContext::sw_pix_fmt
enum AVPixelFormat sw_pix_fmt
Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
AVCodecParserContext::cur_frame_dts
int64_t cur_frame_dts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2879
AVCodecContext::codec_whitelist
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avcodec.h:1873
AVDiscard
AVDiscard
Definition: defs.h:67
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:626
AVCodecParserContext::last_dts
int64_t last_dts
Definition: avcodec.h:2872
codec_desc.h
int
int
Definition: ffmpeg_filter.c:156
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:1569
AVHWAccel::pix_fmt
enum AVPixelFormat pix_fmt
Supported pixel format.
Definition: avcodec.h:2130
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:801
AVSubtitle::start_display_time
uint32_t start_display_time
Definition: avcodec.h:2359
AVCodecContext::compression_level
int compression_level
Definition: avcodec.h:503
av_parser_close
void av_parser_close(AVCodecParserContext *s)
Definition: parser.c:189
AVHWAccel::id
enum AVCodecID id
Codec implemented by the hardware accelerator.
Definition: avcodec.h:2123