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"
35 #include "libavutil/dict.h"
36 #include "libavutil/frame.h"
37 #include "libavutil/log.h"
38 #include "libavutil/pixfmt.h"
39 #include "libavutil/rational.h"
40 
41 #include "codec.h"
42 #include "codec_id.h"
43 #include "defs.h"
44 #include "packet.h"
45 #include "version_major.h"
46 #ifndef HAVE_AV_CONFIG_H
47 /* When included as part of the ffmpeg build, only include the major version
48  * to avoid unnecessary rebuilds. When included externally, keep including
49  * the full version information. */
50 #include "version.h"
51 
52 #include "codec_desc.h"
53 #include "codec_par.h"
54 #endif
55 
56 struct AVCodecParameters;
57 
58 /**
59  * @defgroup libavc libavcodec
60  * Encoding/Decoding Library
61  *
62  * @{
63  *
64  * @defgroup lavc_decoding Decoding
65  * @{
66  * @}
67  *
68  * @defgroup lavc_encoding Encoding
69  * @{
70  * @}
71  *
72  * @defgroup lavc_codec Codecs
73  * @{
74  * @defgroup lavc_codec_native Native Codecs
75  * @{
76  * @}
77  * @defgroup lavc_codec_wrappers External library wrappers
78  * @{
79  * @}
80  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
81  * @{
82  * @}
83  * @}
84  * @defgroup lavc_internal Internal
85  * @{
86  * @}
87  * @}
88  */
89 
90 /**
91  * @ingroup libavc
92  * @defgroup lavc_encdec send/receive encoding and decoding API overview
93  * @{
94  *
95  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
96  * avcodec_receive_packet() functions provide an encode/decode API, which
97  * decouples input and output.
98  *
99  * The API is very similar for encoding/decoding and audio/video, and works as
100  * follows:
101  * - Set up and open the AVCodecContext as usual.
102  * - Send valid input:
103  * - For decoding, call avcodec_send_packet() to give the decoder raw
104  * compressed data in an AVPacket.
105  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
106  * containing uncompressed audio or video.
107  *
108  * In both cases, it is recommended that AVPackets and AVFrames are
109  * refcounted, or libavcodec might have to copy the input data. (libavformat
110  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
111  * refcounted AVFrames.)
112  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
113  * functions and process their output:
114  * - For decoding, call avcodec_receive_frame(). On success, it will return
115  * an AVFrame containing uncompressed audio or video data.
116  * - For encoding, call avcodec_receive_packet(). On success, it will return
117  * an AVPacket with a compressed frame.
118  *
119  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
120  * AVERROR(EAGAIN) return value means that new input data is required to
121  * return new output. In this case, continue with sending input. For each
122  * input frame/packet, the codec will typically return 1 output frame/packet,
123  * but it can also be 0 or more than 1.
124  *
125  * At the beginning of decoding or encoding, the codec might accept multiple
126  * input frames/packets without returning a frame, until its internal buffers
127  * are filled. This situation is handled transparently if you follow the steps
128  * outlined above.
129  *
130  * In theory, sending input can result in EAGAIN - this should happen only if
131  * not all output was received. You can use this to structure alternative decode
132  * or encode loops other than the one suggested above. For example, you could
133  * try sending new input on each iteration, and try to receive output if that
134  * returns EAGAIN.
135  *
136  * End of stream situations. These require "flushing" (aka draining) the codec,
137  * as the codec might buffer multiple frames or packets internally for
138  * performance or out of necessity (consider B-frames).
139  * This is handled as follows:
140  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
141  * or avcodec_send_frame() (encoding) functions. This will enter draining
142  * mode.
143  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
144  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
145  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
146  * - Before decoding can be resumed again, the codec has to be reset with
147  * avcodec_flush_buffers().
148  *
149  * Using the API as outlined above is highly recommended. But it is also
150  * possible to call functions outside of this rigid schema. For example, you can
151  * call avcodec_send_packet() repeatedly without calling
152  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
153  * until the codec's internal buffer has been filled up (which is typically of
154  * size 1 per output frame, after initial input), and then reject input with
155  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
156  * read at least some output.
157  *
158  * Not all codecs will follow a rigid and predictable dataflow; the only
159  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
160  * one end implies that a receive/send call on the other end will succeed, or
161  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
162  * permit unlimited buffering of input or output.
163  *
164  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
165  * would be an invalid state, which could put the codec user into an endless
166  * loop. The API has no concept of time either: it cannot happen that trying to
167  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
168  * later accepts the packet (with no other receive/flush API calls involved).
169  * The API is a strict state machine, and the passage of time is not supposed
170  * to influence it. Some timing-dependent behavior might still be deemed
171  * acceptable in certain cases. But it must never result in both send/receive
172  * returning EAGAIN at the same time at any point. It must also absolutely be
173  * avoided that the current state is "unstable" and can "flip-flop" between
174  * the send/receive APIs allowing progress. For example, it's not allowed that
175  * the codec randomly decides that it actually wants to consume a packet now
176  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
177  * avcodec_send_packet() call.
178  * @}
179  */
180 
181 /**
182  * @defgroup lavc_core Core functions/structures.
183  * @ingroup libavc
184  *
185  * Basic definitions, functions for querying libavcodec capabilities,
186  * allocating core structures, etc.
187  * @{
188  */
189 
190 #if FF_API_BUFFER_MIN_SIZE
191 /**
192  * @ingroup lavc_encoding
193  * minimum encoding buffer size
194  * Used to avoid some checks during header writing.
195  * @deprecated Unused: avcodec_receive_packet() does not work
196  * with preallocated packet buffers.
197  */
198 #define AV_INPUT_BUFFER_MIN_SIZE 16384
199 #endif
200 
201 /**
202  * @ingroup lavc_encoding
203  */
204 typedef struct RcOverride{
207  int qscale; // If this is 0 then quality_factor will be used instead.
209 } RcOverride;
210 
211 /* encoding support
212  These flags can be passed in AVCodecContext.flags before initialization.
213  Note: Not everything is supported yet.
214 */
215 
216 /**
217  * Allow decoders to produce frames with data planes that are not aligned
218  * to CPU requirements (e.g. due to cropping).
219  */
220 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
221 /**
222  * Use fixed qscale.
223  */
224 #define AV_CODEC_FLAG_QSCALE (1 << 1)
225 /**
226  * 4 MV per MB allowed / advanced prediction for H.263.
227  */
228 #define AV_CODEC_FLAG_4MV (1 << 2)
229 /**
230  * Output even those frames that might be corrupted.
231  */
232 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
233 /**
234  * Use qpel MC.
235  */
236 #define AV_CODEC_FLAG_QPEL (1 << 4)
237 #if FF_API_DROPCHANGED
238 /**
239  * Don't output frames whose parameters differ from first
240  * decoded frame in stream.
241  *
242  * @deprecated callers should implement this functionality in their own code
243  */
244 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
245 #endif
246 /**
247  * Request the encoder to output reconstructed frames, i.e.\ frames that would
248  * be produced by decoding the encoded bistream. These frames may be retrieved
249  * by calling avcodec_receive_frame() immediately after a successful call to
250  * avcodec_receive_packet().
251  *
252  * Should only be used with encoders flagged with the
253  * @ref AV_CODEC_CAP_ENCODER_RECON_FRAME capability.
254  *
255  * @note
256  * Each reconstructed frame returned by the encoder corresponds to the last
257  * encoded packet, i.e. the frames are returned in coded order rather than
258  * presentation order.
259  *
260  * @note
261  * Frame parameters (like pixel format or dimensions) do not have to match the
262  * AVCodecContext values. Make sure to use the values from the returned frame.
263  */
264 #define AV_CODEC_FLAG_RECON_FRAME (1 << 6)
265 /**
266  * @par decoding
267  * Request the decoder to propagate each packet's AVPacket.opaque and
268  * AVPacket.opaque_ref to its corresponding output AVFrame.
269  *
270  * @par encoding:
271  * Request the encoder to propagate each frame's AVFrame.opaque and
272  * AVFrame.opaque_ref values to its corresponding output AVPacket.
273  *
274  * @par
275  * May only be set on encoders that have the
276  * @ref AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability flag.
277  *
278  * @note
279  * While in typical cases one input frame produces exactly one output packet
280  * (perhaps after a delay), in general the mapping of frames to packets is
281  * M-to-N, so
282  * - Any number of input frames may be associated with any given output packet.
283  * This includes zero - e.g. some encoders may output packets that carry only
284  * metadata about the whole stream.
285  * - A given input frame may be associated with any number of output packets.
286  * Again this includes zero - e.g. some encoders may drop frames under certain
287  * conditions.
288  * .
289  * This implies that when using this flag, the caller must NOT assume that
290  * - a given input frame's opaques will necessarily appear on some output packet;
291  * - every output packet will have some non-NULL opaque value.
292  * .
293  * When an output packet contains multiple frames, the opaque values will be
294  * taken from the first of those.
295  *
296  * @note
297  * The converse holds for decoders, with frames and packets switched.
298  */
299 #define AV_CODEC_FLAG_COPY_OPAQUE (1 << 7)
300 /**
301  * Signal to the encoder that the values of AVFrame.duration are valid and
302  * should be used (typically for transferring them to output packets).
303  *
304  * If this flag is not set, frame durations are ignored.
305  */
306 #define AV_CODEC_FLAG_FRAME_DURATION (1 << 8)
307 /**
308  * Use internal 2pass ratecontrol in first pass mode.
309  */
310 #define AV_CODEC_FLAG_PASS1 (1 << 9)
311 /**
312  * Use internal 2pass ratecontrol in second pass mode.
313  */
314 #define AV_CODEC_FLAG_PASS2 (1 << 10)
315 /**
316  * loop filter.
317  */
318 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
319 /**
320  * Only decode/encode grayscale.
321  */
322 #define AV_CODEC_FLAG_GRAY (1 << 13)
323 /**
324  * error[?] variables will be set during encoding.
325  */
326 #define AV_CODEC_FLAG_PSNR (1 << 15)
327 /**
328  * Use interlaced DCT.
329  */
330 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
331 /**
332  * Force low delay.
333  */
334 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
335 /**
336  * Place global headers in extradata instead of every keyframe.
337  */
338 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
339 /**
340  * Use only bitexact stuff (except (I)DCT).
341  */
342 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
343 /* Fx : Flag for H.263+ extra options */
344 /**
345  * H.263 advanced intra coding / MPEG-4 AC prediction
346  */
347 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
348 /**
349  * interlaced motion estimation
350  */
351 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
352 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
353 
354 /**
355  * Allow non spec compliant speedup tricks.
356  */
357 #define AV_CODEC_FLAG2_FAST (1 << 0)
358 /**
359  * Skip bitstream encoding.
360  */
361 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
362 /**
363  * Place global headers at every keyframe instead of in extradata.
364  */
365 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
366 
367 /**
368  * Input bitstream might be truncated at a packet boundaries
369  * instead of only at frame boundaries.
370  */
371 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
372 /**
373  * Discard cropping information from SPS.
374  */
375 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
376 
377 /**
378  * Show all frames before the first keyframe
379  */
380 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
381 /**
382  * Export motion vectors through frame side data
383  */
384 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
385 /**
386  * Do not skip samples and export skip information as frame side data
387  */
388 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
389 /**
390  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
391  */
392 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
393 /**
394  * Generate/parse ICC profiles on encode/decode, as appropriate for the type of
395  * file. No effect on codecs which cannot contain embedded ICC profiles, or
396  * when compiled without support for lcms2.
397  */
398 #define AV_CODEC_FLAG2_ICC_PROFILES (1U << 31)
399 
400 /* Exported side data.
401  These flags can be passed in AVCodecContext.export_side_data before initialization.
402 */
403 /**
404  * Export motion vectors through frame side data
405  */
406 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
407 /**
408  * Export encoder Producer Reference Time through packet side data
409  */
410 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
411 /**
412  * Decoding only.
413  * Export the AVVideoEncParams structure through frame side data.
414  */
415 #define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
416 /**
417  * Decoding only.
418  * Do not apply film grain, export it instead.
419  */
420 #define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
421 
422 /**
423  * The decoder will keep a reference to the frame and may reuse it later.
424  */
425 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
426 
427 /**
428  * The encoder will keep a reference to the packet and may reuse it later.
429  */
430 #define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
431 
432 /**
433  * main external API structure.
434  * New fields can be added to the end with minor version bumps.
435  * Removal, reordering and changes to existing fields require a major
436  * version bump.
437  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
438  * applications.
439  * The name string for AVOptions options matches the associated command line
440  * parameter name and can be found in libavcodec/options_table.h
441  * The AVOption/command line parameter names differ in some cases from the C
442  * structure field names for historic reasons or brevity.
443  * sizeof(AVCodecContext) must not be used outside libav*.
444  */
445 typedef struct AVCodecContext {
446  /**
447  * information on struct for av_log
448  * - set by avcodec_alloc_context3
449  */
452 
453  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
454  const struct AVCodec *codec;
455  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
456 
457  /**
458  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
459  * This is used to work around some encoder bugs.
460  * A demuxer should set this to what is stored in the field used to identify the codec.
461  * If there are multiple such fields in a container then the demuxer should choose the one
462  * which maximizes the information about the used codec.
463  * If the codec tag field in a container is larger than 32 bits then the demuxer should
464  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
465  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
466  * first.
467  * - encoding: Set by user, if not then the default based on codec_id will be used.
468  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
469  */
470  unsigned int codec_tag;
471 
472  void *priv_data;
473 
474  /**
475  * Private context used for internal data.
476  *
477  * Unlike priv_data, this is not codec-specific. It is used in general
478  * libavcodec functions.
479  */
480  struct AVCodecInternal *internal;
481 
482  /**
483  * Private data of the user, can be used to carry app specific stuff.
484  * - encoding: Set by user.
485  * - decoding: Set by user.
486  */
487  void *opaque;
488 
489  /**
490  * the average bitrate
491  * - encoding: Set by user; unused for constant quantizer encoding.
492  * - decoding: Set by user, may be overwritten by libavcodec
493  * if this info is available in the stream
494  */
495  int64_t bit_rate;
496 
497  /**
498  * number of bits the bitstream is allowed to diverge from the reference.
499  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
500  * - encoding: Set by user; unused for constant quantizer encoding.
501  * - decoding: unused
502  */
504 
505  /**
506  * Global quality for codecs which cannot change it per frame.
507  * This should be proportional to MPEG-1/2/4 qscale.
508  * - encoding: Set by user.
509  * - decoding: unused
510  */
512 
513  /**
514  * - encoding: Set by user.
515  * - decoding: unused
516  */
518 #define FF_COMPRESSION_DEFAULT -1
519 
520  /**
521  * AV_CODEC_FLAG_*.
522  * - encoding: Set by user.
523  * - decoding: Set by user.
524  */
525  int flags;
526 
527  /**
528  * AV_CODEC_FLAG2_*
529  * - encoding: Set by user.
530  * - decoding: Set by user.
531  */
532  int flags2;
533 
534  /**
535  * some codecs need / can use extradata like Huffman tables.
536  * MJPEG: Huffman tables
537  * rv10: additional flags
538  * MPEG-4: global headers (they can be in the bitstream or here)
539  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
540  * than extradata_size to avoid problems if it is read with the bitstream reader.
541  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
542  * Must be allocated with the av_malloc() family of functions.
543  * - encoding: Set/allocated/freed by libavcodec.
544  * - decoding: Set/allocated/freed by user.
545  */
546  uint8_t *extradata;
548 
549  /**
550  * This is the fundamental unit of time (in seconds) in terms
551  * of which frame timestamps are represented. For fixed-fps content,
552  * timebase should be 1/framerate and timestamp increments should be
553  * identically 1.
554  * This often, but not always is the inverse of the frame rate or field rate
555  * for video. 1/time_base is not the average frame rate if the frame rate is not
556  * constant.
557  *
558  * Like containers, elementary streams also can store timestamps, 1/time_base
559  * is the unit in which these timestamps are specified.
560  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
561  * vop_time_increment_resolution and fixed_vop_rate
562  * (fixed_vop_rate == 0 implies that it is different from the framerate)
563  *
564  * - encoding: MUST be set by user.
565  * - decoding: unused.
566  */
568 
569 #if FF_API_TICKS_PER_FRAME
570  /**
571  * For some codecs, the time base is closer to the field rate than the frame rate.
572  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
573  * if no telecine is used ...
574  *
575  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
576  *
577  * @deprecated
578  * - decoding: Use AVCodecDescriptor.props & AV_CODEC_PROP_FIELDS
579  * - encoding: Set AVCodecContext.framerate instead
580  *
581  */
584 #endif
585 
586  /**
587  * Codec delay.
588  *
589  * Encoding: Number of frames delay there will be from the encoder input to
590  * the decoder output. (we assume the decoder matches the spec)
591  * Decoding: Number of frames delay in addition to what a standard decoder
592  * as specified in the spec would produce.
593  *
594  * Video:
595  * Number of frames the decoded output will be delayed relative to the
596  * encoded input.
597  *
598  * Audio:
599  * For encoding, this field is unused (see initial_padding).
600  *
601  * For decoding, this is the number of samples the decoder needs to
602  * output before the decoder's output is valid. When seeking, you should
603  * start decoding this many samples prior to your desired seek point.
604  *
605  * - encoding: Set by libavcodec.
606  * - decoding: Set by libavcodec.
607  */
608  int delay;
609 
610 
611  /* video only */
612  /**
613  * picture width / height.
614  *
615  * @note Those fields may not match the values of the last
616  * AVFrame output by avcodec_receive_frame() due frame
617  * reordering.
618  *
619  * - encoding: MUST be set by user.
620  * - decoding: May be set by the user before opening the decoder if known e.g.
621  * from the container. Some decoders will require the dimensions
622  * to be set by the caller. During decoding, the decoder may
623  * overwrite those values as required while parsing the data.
624  */
625  int width, height;
626 
627  /**
628  * Bitstream width / height, may be different from width/height e.g. when
629  * the decoded frame is cropped before being output or lowres is enabled.
630  *
631  * @note Those field may not match the value of the last
632  * AVFrame output by avcodec_receive_frame() due frame
633  * reordering.
634  *
635  * - encoding: unused
636  * - decoding: May be set by the user before opening the decoder if known
637  * e.g. from the container. During decoding, the decoder may
638  * overwrite those values as required while parsing the data.
639  */
641 
642  /**
643  * the number of pictures in a group of pictures, or 0 for intra_only
644  * - encoding: Set by user.
645  * - decoding: unused
646  */
647  int gop_size;
648 
649  /**
650  * Pixel format, see AV_PIX_FMT_xxx.
651  * May be set by the demuxer if known from headers.
652  * May be overridden by the decoder if it knows better.
653  *
654  * @note This field may not match the value of the last
655  * AVFrame output by avcodec_receive_frame() due frame
656  * reordering.
657  *
658  * - encoding: Set by user.
659  * - decoding: Set by user if known, overridden by libavcodec while
660  * parsing the data.
661  */
663 
664  /**
665  * If non NULL, 'draw_horiz_band' is called by the libavcodec
666  * decoder to draw a horizontal band. It improves cache usage. Not
667  * all codecs can do that. You must check the codec capabilities
668  * beforehand.
669  * When multithreading is used, it may be called from multiple threads
670  * at the same time; threads might draw different parts of the same AVFrame,
671  * or multiple AVFrames, and there is no guarantee that slices will be drawn
672  * in order.
673  * The function is also used by hardware acceleration APIs.
674  * It is called at least once during frame decoding to pass
675  * the data needed for hardware render.
676  * In that mode instead of pixel data, AVFrame points to
677  * a structure specific to the acceleration API. The application
678  * reads the structure and can change some fields to indicate progress
679  * or mark state.
680  * - encoding: unused
681  * - decoding: Set by user.
682  * @param height the height of the slice
683  * @param y the y position of the slice
684  * @param type 1->top field, 2->bottom field, 3->frame
685  * @param offset offset into the AVFrame.data from which the slice should be read
686  */
688  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
689  int y, int type, int height);
690 
691  /**
692  * Callback to negotiate the pixel format. Decoding only, may be set by the
693  * caller before avcodec_open2().
694  *
695  * Called by some decoders to select the pixel format that will be used for
696  * the output frames. This is mainly used to set up hardware acceleration,
697  * then the provided format list contains the corresponding hwaccel pixel
698  * formats alongside the "software" one. The software pixel format may also
699  * be retrieved from \ref sw_pix_fmt.
700  *
701  * This callback will be called when the coded frame properties (such as
702  * resolution, pixel format, etc.) change and more than one output format is
703  * supported for those new properties. If a hardware pixel format is chosen
704  * and initialization for it fails, the callback may be called again
705  * immediately.
706  *
707  * This callback may be called from different threads if the decoder is
708  * multi-threaded, but not from more than one thread simultaneously.
709  *
710  * @param fmt list of formats which may be used in the current
711  * configuration, terminated by AV_PIX_FMT_NONE.
712  * @warning Behavior is undefined if the callback returns a value other
713  * than one of the formats in fmt or AV_PIX_FMT_NONE.
714  * @return the chosen format or AV_PIX_FMT_NONE
715  */
716  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
717 
718  /**
719  * maximum number of B-frames between non-B-frames
720  * Note: The output will be delayed by max_b_frames+1 relative to the input.
721  * - encoding: Set by user.
722  * - decoding: unused
723  */
725 
726  /**
727  * qscale factor between IP and B-frames
728  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
729  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
730  * - encoding: Set by user.
731  * - decoding: unused
732  */
734 
735  /**
736  * qscale offset between IP and B-frames
737  * - encoding: Set by user.
738  * - decoding: unused
739  */
741 
742  /**
743  * Size of the frame reordering buffer in the decoder.
744  * For MPEG-2 it is 1 IPB or 0 low delay IP.
745  * - encoding: Set by libavcodec.
746  * - decoding: Set by libavcodec.
747  */
749 
750  /**
751  * qscale factor between P- and I-frames
752  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
753  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
754  * - encoding: Set by user.
755  * - decoding: unused
756  */
758 
759  /**
760  * qscale offset between P and I-frames
761  * - encoding: Set by user.
762  * - decoding: unused
763  */
765 
766  /**
767  * luminance masking (0-> disabled)
768  * - encoding: Set by user.
769  * - decoding: unused
770  */
772 
773  /**
774  * temporary complexity masking (0-> disabled)
775  * - encoding: Set by user.
776  * - decoding: unused
777  */
779 
780  /**
781  * spatial complexity masking (0-> disabled)
782  * - encoding: Set by user.
783  * - decoding: unused
784  */
786 
787  /**
788  * p block masking (0-> disabled)
789  * - encoding: Set by user.
790  * - decoding: unused
791  */
792  float p_masking;
793 
794  /**
795  * darkness masking (0-> disabled)
796  * - encoding: Set by user.
797  * - decoding: unused
798  */
800 
801 #if FF_API_SLICE_OFFSET
802  /**
803  * slice count
804  * - encoding: Set by libavcodec.
805  * - decoding: Set by user (or 0).
806  */
809 
810  /**
811  * slice offsets in the frame in bytes
812  * - encoding: Set/allocated by libavcodec.
813  * - decoding: Set/allocated by user (or NULL).
814  */
817 #endif
818 
819  /**
820  * sample aspect ratio (0 if unknown)
821  * That is the width of a pixel divided by the height of the pixel.
822  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
823  * - encoding: Set by user.
824  * - decoding: Set by libavcodec.
825  */
827 
828  /**
829  * motion estimation comparison function
830  * - encoding: Set by user.
831  * - decoding: unused
832  */
833  int me_cmp;
834  /**
835  * subpixel motion estimation comparison function
836  * - encoding: Set by user.
837  * - decoding: unused
838  */
840  /**
841  * macroblock comparison function (not supported yet)
842  * - encoding: Set by user.
843  * - decoding: unused
844  */
845  int mb_cmp;
846  /**
847  * interlaced DCT comparison function
848  * - encoding: Set by user.
849  * - decoding: unused
850  */
852 #define FF_CMP_SAD 0
853 #define FF_CMP_SSE 1
854 #define FF_CMP_SATD 2
855 #define FF_CMP_DCT 3
856 #define FF_CMP_PSNR 4
857 #define FF_CMP_BIT 5
858 #define FF_CMP_RD 6
859 #define FF_CMP_ZERO 7
860 #define FF_CMP_VSAD 8
861 #define FF_CMP_VSSE 9
862 #define FF_CMP_NSSE 10
863 #define FF_CMP_W53 11
864 #define FF_CMP_W97 12
865 #define FF_CMP_DCTMAX 13
866 #define FF_CMP_DCT264 14
867 #define FF_CMP_MEDIAN_SAD 15
868 #define FF_CMP_CHROMA 256
869 
870  /**
871  * ME diamond size & shape
872  * - encoding: Set by user.
873  * - decoding: unused
874  */
875  int dia_size;
876 
877  /**
878  * amount of previous MV predictors (2a+1 x 2a+1 square)
879  * - encoding: Set by user.
880  * - decoding: unused
881  */
883 
884  /**
885  * motion estimation prepass comparison function
886  * - encoding: Set by user.
887  * - decoding: unused
888  */
890 
891  /**
892  * ME prepass diamond size & shape
893  * - encoding: Set by user.
894  * - decoding: unused
895  */
897 
898  /**
899  * subpel ME quality
900  * - encoding: Set by user.
901  * - decoding: unused
902  */
904 
905  /**
906  * maximum motion estimation search range in subpel units
907  * If 0 then no limit.
908  *
909  * - encoding: Set by user.
910  * - decoding: unused
911  */
912  int me_range;
913 
914  /**
915  * slice flags
916  * - encoding: unused
917  * - decoding: Set by user.
918  */
920 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
921 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
922 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
923 
924  /**
925  * macroblock decision mode
926  * - encoding: Set by user.
927  * - decoding: unused
928  */
930 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
931 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
932 #define FF_MB_DECISION_RD 2 ///< rate distortion
933 
934  /**
935  * custom intra quantization matrix
936  * Must be allocated with the av_malloc() family of functions, and will be freed in
937  * avcodec_free_context().
938  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
939  * - decoding: Set/allocated/freed by libavcodec.
940  */
941  uint16_t *intra_matrix;
942 
943  /**
944  * custom inter quantization matrix
945  * Must be allocated with the av_malloc() family of functions, and will be freed in
946  * avcodec_free_context().
947  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
948  * - decoding: Set/allocated/freed by libavcodec.
949  */
950  uint16_t *inter_matrix;
951 
952  /**
953  * precision of the intra DC coefficient - 8
954  * - encoding: Set by user.
955  * - decoding: Set by libavcodec
956  */
958 
959  /**
960  * Number of macroblock rows at the top which are skipped.
961  * - encoding: unused
962  * - decoding: Set by user.
963  */
964  int skip_top;
965 
966  /**
967  * Number of macroblock rows at the bottom which are skipped.
968  * - encoding: unused
969  * - decoding: Set by user.
970  */
972 
973  /**
974  * minimum MB Lagrange multiplier
975  * - encoding: Set by user.
976  * - decoding: unused
977  */
978  int mb_lmin;
979 
980  /**
981  * maximum MB Lagrange multiplier
982  * - encoding: Set by user.
983  * - decoding: unused
984  */
985  int mb_lmax;
986 
987  /**
988  * - encoding: Set by user.
989  * - decoding: unused
990  */
992 
993  /**
994  * minimum GOP size
995  * - encoding: Set by user.
996  * - decoding: unused
997  */
999 
1000  /**
1001  * number of reference frames
1002  * - encoding: Set by user.
1003  * - decoding: Set by lavc.
1004  */
1005  int refs;
1006 
1007  /**
1008  * Note: Value depends upon the compare function used for fullpel ME.
1009  * - encoding: Set by user.
1010  * - decoding: unused
1011  */
1013 
1014  /**
1015  * Chromaticity coordinates of the source primaries.
1016  * - encoding: Set by user
1017  * - decoding: Set by libavcodec
1018  */
1020 
1021  /**
1022  * Color Transfer Characteristic.
1023  * - encoding: Set by user
1024  * - decoding: Set by libavcodec
1025  */
1027 
1028  /**
1029  * YUV colorspace type.
1030  * - encoding: Set by user
1031  * - decoding: Set by libavcodec
1032  */
1034 
1035  /**
1036  * MPEG vs JPEG YUV range.
1037  * - encoding: Set by user to override the default output color range value,
1038  * If not specified, libavcodec sets the color range depending on the
1039  * output format.
1040  * - decoding: Set by libavcodec, can be set by the user to propagate the
1041  * color range to components reading from the decoder context.
1042  */
1044 
1045  /**
1046  * This defines the location of chroma samples.
1047  * - encoding: Set by user
1048  * - decoding: Set by libavcodec
1049  */
1051 
1052  /**
1053  * Number of slices.
1054  * Indicates number of picture subdivisions. Used for parallelized
1055  * decoding.
1056  * - encoding: Set by user
1057  * - decoding: unused
1058  */
1059  int slices;
1060 
1061  /** Field order
1062  * - encoding: set by libavcodec
1063  * - decoding: Set by user.
1064  */
1066 
1067  /* audio only */
1068  int sample_rate; ///< samples per second
1069 
1070 #if FF_API_OLD_CHANNEL_LAYOUT
1071  /**
1072  * number of audio channels
1073  * @deprecated use ch_layout.nb_channels
1074  */
1076  int channels;
1077 #endif
1078 
1079  /**
1080  * audio sample format
1081  * - encoding: Set by user.
1082  * - decoding: Set by libavcodec.
1083  */
1084  enum AVSampleFormat sample_fmt; ///< sample format
1085 
1086  /* The following data should not be initialized. */
1087  /**
1088  * Number of samples per channel in an audio frame.
1089  *
1090  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1091  * except the last must contain exactly frame_size samples per channel.
1092  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1093  * frame size is not restricted.
1094  * - decoding: may be set by some decoders to indicate constant frame size
1095  */
1097 
1098 #if FF_API_AVCTX_FRAME_NUMBER
1099  /**
1100  * Frame counter, set by libavcodec.
1101  *
1102  * - decoding: total number of frames returned from the decoder so far.
1103  * - encoding: total number of frames passed to the encoder so far.
1104  *
1105  * @note the counter is not incremented if encoding/decoding resulted in
1106  * an error.
1107  * @deprecated use frame_num instead
1108  */
1111 #endif
1112 
1113  /**
1114  * number of bytes per packet if constant and known or 0
1115  * Used by some WAV based audio codecs.
1116  */
1118 
1119  /**
1120  * Audio cutoff bandwidth (0 means "automatic")
1121  * - encoding: Set by user.
1122  * - decoding: unused
1123  */
1124  int cutoff;
1125 
1126 #if FF_API_OLD_CHANNEL_LAYOUT
1127  /**
1128  * Audio channel layout.
1129  * - encoding: set by user.
1130  * - decoding: set by user, may be overwritten by libavcodec.
1131  * @deprecated use ch_layout
1132  */
1134  uint64_t channel_layout;
1135 
1136  /**
1137  * Request decoder to use this channel layout if it can (0 for default)
1138  * - encoding: unused
1139  * - decoding: Set by user.
1140  * @deprecated use "downmix" codec private option
1141  */
1143  uint64_t request_channel_layout;
1144 #endif
1145 
1146  /**
1147  * Type of service that the audio stream conveys.
1148  * - encoding: Set by user.
1149  * - decoding: Set by libavcodec.
1150  */
1152 
1153  /**
1154  * desired sample format
1155  * - encoding: Not used.
1156  * - decoding: Set by user.
1157  * Decoder will decode to this format if it can.
1158  */
1160 
1161  /**
1162  * This callback is called at the beginning of each frame to get data
1163  * buffer(s) for it. There may be one contiguous buffer for all the data or
1164  * there may be a buffer per each data plane or anything in between. What
1165  * this means is, you may set however many entries in buf[] you feel necessary.
1166  * Each buffer must be reference-counted using the AVBuffer API (see description
1167  * of buf[] below).
1168  *
1169  * The following fields will be set in the frame before this callback is
1170  * called:
1171  * - format
1172  * - width, height (video only)
1173  * - sample_rate, channel_layout, nb_samples (audio only)
1174  * Their values may differ from the corresponding values in
1175  * AVCodecContext. This callback must use the frame values, not the codec
1176  * context values, to calculate the required buffer size.
1177  *
1178  * This callback must fill the following fields in the frame:
1179  * - data[]
1180  * - linesize[]
1181  * - extended_data:
1182  * * if the data is planar audio with more than 8 channels, then this
1183  * callback must allocate and fill extended_data to contain all pointers
1184  * to all data planes. data[] must hold as many pointers as it can.
1185  * extended_data must be allocated with av_malloc() and will be freed in
1186  * av_frame_unref().
1187  * * otherwise extended_data must point to data
1188  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1189  * the frame's data and extended_data pointers must be contained in these. That
1190  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1191  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1192  * and av_buffer_ref().
1193  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1194  * this callback and filled with the extra buffers if there are more
1195  * buffers than buf[] can hold. extended_buf will be freed in
1196  * av_frame_unref().
1197  *
1198  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1199  * avcodec_default_get_buffer2() instead of providing buffers allocated by
1200  * some other means.
1201  *
1202  * Each data plane must be aligned to the maximum required by the target
1203  * CPU.
1204  *
1205  * @see avcodec_default_get_buffer2()
1206  *
1207  * Video:
1208  *
1209  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1210  * (read and/or written to if it is writable) later by libavcodec.
1211  *
1212  * avcodec_align_dimensions2() should be used to find the required width and
1213  * height, as they normally need to be rounded up to the next multiple of 16.
1214  *
1215  * Some decoders do not support linesizes changing between frames.
1216  *
1217  * If frame multithreading is used, this callback may be called from a
1218  * different thread, but not from more than one at once. Does not need to be
1219  * reentrant.
1220  *
1221  * @see avcodec_align_dimensions2()
1222  *
1223  * Audio:
1224  *
1225  * Decoders request a buffer of a particular size by setting
1226  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1227  * however, utilize only part of the buffer by setting AVFrame.nb_samples
1228  * to a smaller value in the output frame.
1229  *
1230  * As a convenience, av_samples_get_buffer_size() and
1231  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1232  * functions to find the required data size and to fill data pointers and
1233  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1234  * since all planes must be the same size.
1235  *
1236  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1237  *
1238  * - encoding: unused
1239  * - decoding: Set by libavcodec, user can override.
1240  */
1242 
1243  /* - encoding parameters */
1244  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1245  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1246 
1247  /**
1248  * minimum quantizer
1249  * - encoding: Set by user.
1250  * - decoding: unused
1251  */
1252  int qmin;
1253 
1254  /**
1255  * maximum quantizer
1256  * - encoding: Set by user.
1257  * - decoding: unused
1258  */
1259  int qmax;
1260 
1261  /**
1262  * maximum quantizer difference between frames
1263  * - encoding: Set by user.
1264  * - decoding: unused
1265  */
1267 
1268  /**
1269  * decoder bitstream buffer size
1270  * - encoding: Set by user.
1271  * - decoding: May be set by libavcodec.
1272  */
1274 
1275  /**
1276  * ratecontrol override, see RcOverride
1277  * - encoding: Allocated/set/freed by user.
1278  * - decoding: unused
1279  */
1282 
1283  /**
1284  * maximum bitrate
1285  * - encoding: Set by user.
1286  * - decoding: Set by user, may be overwritten by libavcodec.
1287  */
1288  int64_t rc_max_rate;
1289 
1290  /**
1291  * minimum bitrate
1292  * - encoding: Set by user.
1293  * - decoding: unused
1294  */
1295  int64_t rc_min_rate;
1296 
1297  /**
1298  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1299  * - encoding: Set by user.
1300  * - decoding: unused.
1301  */
1303 
1304  /**
1305  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1306  * - encoding: Set by user.
1307  * - decoding: unused.
1308  */
1310 
1311  /**
1312  * Number of bits which should be loaded into the rc buffer before decoding starts.
1313  * - encoding: Set by user.
1314  * - decoding: unused
1315  */
1317 
1318  /**
1319  * trellis RD quantization
1320  * - encoding: Set by user.
1321  * - decoding: unused
1322  */
1323  int trellis;
1324 
1325  /**
1326  * pass1 encoding statistics output buffer
1327  * - encoding: Set by libavcodec.
1328  * - decoding: unused
1329  */
1330  char *stats_out;
1331 
1332  /**
1333  * pass2 encoding statistics input buffer
1334  * Concatenated stuff from stats_out of pass1 should be placed here.
1335  * - encoding: Allocated/set/freed by user.
1336  * - decoding: unused
1337  */
1338  char *stats_in;
1339 
1340  /**
1341  * Work around bugs in encoders which sometimes cannot be detected automatically.
1342  * - encoding: Set by user
1343  * - decoding: Set by user
1344  */
1346 #define FF_BUG_AUTODETECT 1 ///< autodetection
1347 #define FF_BUG_XVID_ILACE 4
1348 #define FF_BUG_UMP4 8
1349 #define FF_BUG_NO_PADDING 16
1350 #define FF_BUG_AMV 32
1351 #define FF_BUG_QPEL_CHROMA 64
1352 #define FF_BUG_STD_QPEL 128
1353 #define FF_BUG_QPEL_CHROMA2 256
1354 #define FF_BUG_DIRECT_BLOCKSIZE 512
1355 #define FF_BUG_EDGE 1024
1356 #define FF_BUG_HPEL_CHROMA 2048
1357 #define FF_BUG_DC_CLIP 4096
1358 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1359 #define FF_BUG_TRUNCATED 16384
1360 #define FF_BUG_IEDGE 32768
1361 
1362  /**
1363  * strictly follow the standard (MPEG-4, ...).
1364  * - encoding: Set by user.
1365  * - decoding: Set by user.
1366  * Setting this to STRICT or higher means the encoder and decoder will
1367  * generally do stupid things, whereas setting it to unofficial or lower
1368  * will mean the encoder might produce output that is not supported by all
1369  * spec-compliant decoders. Decoders don't differentiate between normal,
1370  * unofficial and experimental (that is, they always try to decode things
1371  * when they can) unless they are explicitly asked to behave stupidly
1372  * (=strictly conform to the specs)
1373  * This may only be set to one of the FF_COMPLIANCE_* values in defs.h.
1374  */
1376 
1377  /**
1378  * error concealment flags
1379  * - encoding: unused
1380  * - decoding: Set by user.
1381  */
1383 #define FF_EC_GUESS_MVS 1
1384 #define FF_EC_DEBLOCK 2
1385 #define FF_EC_FAVOR_INTER 256
1386 
1387  /**
1388  * debug
1389  * - encoding: Set by user.
1390  * - decoding: Set by user.
1391  */
1392  int debug;
1393 #define FF_DEBUG_PICT_INFO 1
1394 #define FF_DEBUG_RC 2
1395 #define FF_DEBUG_BITSTREAM 4
1396 #define FF_DEBUG_MB_TYPE 8
1397 #define FF_DEBUG_QP 16
1398 #define FF_DEBUG_DCT_COEFF 0x00000040
1399 #define FF_DEBUG_SKIP 0x00000080
1400 #define FF_DEBUG_STARTCODE 0x00000100
1401 #define FF_DEBUG_ER 0x00000400
1402 #define FF_DEBUG_MMCO 0x00000800
1403 #define FF_DEBUG_BUGS 0x00001000
1404 #define FF_DEBUG_BUFFERS 0x00008000
1405 #define FF_DEBUG_THREADS 0x00010000
1406 #define FF_DEBUG_GREEN_MD 0x00800000
1407 #define FF_DEBUG_NOMC 0x01000000
1408 
1409  /**
1410  * Error recognition; may misdetect some more or less valid parts as errors.
1411  * This is a bitfield of the AV_EF_* values defined in defs.h.
1412  *
1413  * - encoding: Set by user.
1414  * - decoding: Set by user.
1415  */
1417 
1418 #if FF_API_REORDERED_OPAQUE
1419  /**
1420  * opaque 64-bit number (generally a PTS) that will be reordered and
1421  * output in AVFrame.reordered_opaque
1422  * - encoding: Set by libavcodec to the reordered_opaque of the input
1423  * frame corresponding to the last returned packet. Only
1424  * supported by encoders with the
1425  * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1426  * - decoding: Set by user.
1427  *
1428  * @deprecated Use AV_CODEC_FLAG_COPY_OPAQUE instead
1429  */
1431  int64_t reordered_opaque;
1432 #endif
1433 
1434  /**
1435  * Hardware accelerator in use
1436  * - encoding: unused.
1437  * - decoding: Set by libavcodec
1438  */
1439  const struct AVHWAccel *hwaccel;
1440 
1441  /**
1442  * Legacy hardware accelerator context.
1443  *
1444  * For some hardware acceleration methods, the caller may use this field to
1445  * signal hwaccel-specific data to the codec. The struct pointed to by this
1446  * pointer is hwaccel-dependent and defined in the respective header. Please
1447  * refer to the FFmpeg HW accelerator documentation to know how to fill
1448  * this.
1449  *
1450  * In most cases this field is optional - the necessary information may also
1451  * be provided to libavcodec through @ref hw_frames_ctx or @ref
1452  * hw_device_ctx (see avcodec_get_hw_config()). However, in some cases it
1453  * may be the only method of signalling some (optional) information.
1454  *
1455  * The struct and its contents are owned by the caller.
1456  *
1457  * - encoding: May be set by the caller before avcodec_open2(). Must remain
1458  * valid until avcodec_free_context().
1459  * - decoding: May be set by the caller in the get_format() callback.
1460  * Must remain valid until the next get_format() call,
1461  * or avcodec_free_context() (whichever comes first).
1462  */
1464 
1465  /**
1466  * error
1467  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1468  * - decoding: unused
1469  */
1471 
1472  /**
1473  * DCT algorithm, see FF_DCT_* below
1474  * - encoding: Set by user.
1475  * - decoding: unused
1476  */
1478 #define FF_DCT_AUTO 0
1479 #define FF_DCT_FASTINT 1
1480 #define FF_DCT_INT 2
1481 #define FF_DCT_MMX 3
1482 #define FF_DCT_ALTIVEC 5
1483 #define FF_DCT_FAAN 6
1484 
1485  /**
1486  * IDCT algorithm, see FF_IDCT_* below.
1487  * - encoding: Set by user.
1488  * - decoding: Set by user.
1489  */
1491 #define FF_IDCT_AUTO 0
1492 #define FF_IDCT_INT 1
1493 #define FF_IDCT_SIMPLE 2
1494 #define FF_IDCT_SIMPLEMMX 3
1495 #define FF_IDCT_ARM 7
1496 #define FF_IDCT_ALTIVEC 8
1497 #define FF_IDCT_SIMPLEARM 10
1498 #define FF_IDCT_XVID 14
1499 #define FF_IDCT_SIMPLEARMV5TE 16
1500 #define FF_IDCT_SIMPLEARMV6 17
1501 #define FF_IDCT_FAAN 20
1502 #define FF_IDCT_SIMPLENEON 22
1503 #if FF_API_IDCT_NONE
1504 // formerly used by xvmc
1505 #define FF_IDCT_NONE 24
1506 #endif
1507 #define FF_IDCT_SIMPLEAUTO 128
1508 
1509  /**
1510  * bits per sample/pixel from the demuxer (needed for huffyuv).
1511  * - encoding: Set by libavcodec.
1512  * - decoding: Set by user.
1513  */
1515 
1516  /**
1517  * Bits per sample/pixel of internal libavcodec pixel/sample format.
1518  * - encoding: set by user.
1519  * - decoding: set by libavcodec.
1520  */
1522 
1523  /**
1524  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1525  * - encoding: unused
1526  * - decoding: Set by user.
1527  */
1528  int lowres;
1529 
1530  /**
1531  * thread count
1532  * is used to decide how many independent tasks should be passed to execute()
1533  * - encoding: Set by user.
1534  * - decoding: Set by user.
1535  */
1537 
1538  /**
1539  * Which multithreading methods to use.
1540  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1541  * so clients which cannot provide future frames should not use it.
1542  *
1543  * - encoding: Set by user, otherwise the default is used.
1544  * - decoding: Set by user, otherwise the default is used.
1545  */
1547 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1548 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1549 
1550  /**
1551  * Which multithreading methods are in use by the codec.
1552  * - encoding: Set by libavcodec.
1553  * - decoding: Set by libavcodec.
1554  */
1556 
1557  /**
1558  * The codec may call this to execute several independent things.
1559  * It will return only after finishing all tasks.
1560  * The user may replace this with some multithreaded implementation,
1561  * the default implementation will execute the parts serially.
1562  * @param count the number of things to execute
1563  * - encoding: Set by libavcodec, user can override.
1564  * - decoding: Set by libavcodec, user can override.
1565  */
1566  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1567 
1568  /**
1569  * The codec may call this to execute several independent things.
1570  * It will return only after finishing all tasks.
1571  * The user may replace this with some multithreaded implementation,
1572  * the default implementation will execute the parts serially.
1573  * @param c context passed also to func
1574  * @param count the number of things to execute
1575  * @param arg2 argument passed unchanged to func
1576  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1577  * @param func function that will be called count times, with jobnr from 0 to count-1.
1578  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1579  * two instances of func executing at the same time will have the same threadnr.
1580  * @return always 0 currently, but code should handle a future improvement where when any call to func
1581  * returns < 0 no further calls to func may be done and < 0 is returned.
1582  * - encoding: Set by libavcodec, user can override.
1583  * - decoding: Set by libavcodec, user can override.
1584  */
1585  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1586 
1587  /**
1588  * noise vs. sse weight for the nsse comparison function
1589  * - encoding: Set by user.
1590  * - decoding: unused
1591  */
1593 
1594  /**
1595  * profile
1596  * - encoding: Set by user.
1597  * - decoding: Set by libavcodec.
1598  * See the AV_PROFILE_* defines in defs.h.
1599  */
1600  int profile;
1601 #if FF_API_FF_PROFILE_LEVEL
1602  /** @deprecated The following defines are deprecated; use AV_PROFILE_*
1603  * in defs.h instead. */
1604 #define FF_PROFILE_UNKNOWN -99
1605 #define FF_PROFILE_RESERVED -100
1606 
1607 #define FF_PROFILE_AAC_MAIN 0
1608 #define FF_PROFILE_AAC_LOW 1
1609 #define FF_PROFILE_AAC_SSR 2
1610 #define FF_PROFILE_AAC_LTP 3
1611 #define FF_PROFILE_AAC_HE 4
1612 #define FF_PROFILE_AAC_HE_V2 28
1613 #define FF_PROFILE_AAC_LD 22
1614 #define FF_PROFILE_AAC_ELD 38
1615 #define FF_PROFILE_MPEG2_AAC_LOW 128
1616 #define FF_PROFILE_MPEG2_AAC_HE 131
1617 
1618 #define FF_PROFILE_DNXHD 0
1619 #define FF_PROFILE_DNXHR_LB 1
1620 #define FF_PROFILE_DNXHR_SQ 2
1621 #define FF_PROFILE_DNXHR_HQ 3
1622 #define FF_PROFILE_DNXHR_HQX 4
1623 #define FF_PROFILE_DNXHR_444 5
1624 
1625 #define FF_PROFILE_DTS 20
1626 #define FF_PROFILE_DTS_ES 30
1627 #define FF_PROFILE_DTS_96_24 40
1628 #define FF_PROFILE_DTS_HD_HRA 50
1629 #define FF_PROFILE_DTS_HD_MA 60
1630 #define FF_PROFILE_DTS_EXPRESS 70
1631 #define FF_PROFILE_DTS_HD_MA_X 61
1632 #define FF_PROFILE_DTS_HD_MA_X_IMAX 62
1633 
1634 
1635 #define FF_PROFILE_EAC3_DDP_ATMOS 30
1636 
1637 #define FF_PROFILE_TRUEHD_ATMOS 30
1638 
1639 #define FF_PROFILE_MPEG2_422 0
1640 #define FF_PROFILE_MPEG2_HIGH 1
1641 #define FF_PROFILE_MPEG2_SS 2
1642 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1643 #define FF_PROFILE_MPEG2_MAIN 4
1644 #define FF_PROFILE_MPEG2_SIMPLE 5
1645 
1646 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1647 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1648 
1649 #define FF_PROFILE_H264_BASELINE 66
1650 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1651 #define FF_PROFILE_H264_MAIN 77
1652 #define FF_PROFILE_H264_EXTENDED 88
1653 #define FF_PROFILE_H264_HIGH 100
1654 #define FF_PROFILE_H264_HIGH_10 110
1655 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1656 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1657 #define FF_PROFILE_H264_HIGH_422 122
1658 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1659 #define FF_PROFILE_H264_STEREO_HIGH 128
1660 #define FF_PROFILE_H264_HIGH_444 144
1661 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1662 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1663 #define FF_PROFILE_H264_CAVLC_444 44
1664 
1665 #define FF_PROFILE_VC1_SIMPLE 0
1666 #define FF_PROFILE_VC1_MAIN 1
1667 #define FF_PROFILE_VC1_COMPLEX 2
1668 #define FF_PROFILE_VC1_ADVANCED 3
1669 
1670 #define FF_PROFILE_MPEG4_SIMPLE 0
1671 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1672 #define FF_PROFILE_MPEG4_CORE 2
1673 #define FF_PROFILE_MPEG4_MAIN 3
1674 #define FF_PROFILE_MPEG4_N_BIT 4
1675 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1676 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1677 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1678 #define FF_PROFILE_MPEG4_HYBRID 8
1679 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1680 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1681 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1682 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1683 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1684 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1685 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1686 
1687 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1688 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1689 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1690 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1691 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1692 
1693 #define FF_PROFILE_VP9_0 0
1694 #define FF_PROFILE_VP9_1 1
1695 #define FF_PROFILE_VP9_2 2
1696 #define FF_PROFILE_VP9_3 3
1697 
1698 #define FF_PROFILE_HEVC_MAIN 1
1699 #define FF_PROFILE_HEVC_MAIN_10 2
1700 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1701 #define FF_PROFILE_HEVC_REXT 4
1702 #define FF_PROFILE_HEVC_SCC 9
1703 
1704 #define FF_PROFILE_VVC_MAIN_10 1
1705 #define FF_PROFILE_VVC_MAIN_10_444 33
1706 
1707 #define FF_PROFILE_AV1_MAIN 0
1708 #define FF_PROFILE_AV1_HIGH 1
1709 #define FF_PROFILE_AV1_PROFESSIONAL 2
1710 
1711 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1712 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1713 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1714 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1715 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1716 
1717 #define FF_PROFILE_SBC_MSBC 1
1718 
1719 #define FF_PROFILE_PRORES_PROXY 0
1720 #define FF_PROFILE_PRORES_LT 1
1721 #define FF_PROFILE_PRORES_STANDARD 2
1722 #define FF_PROFILE_PRORES_HQ 3
1723 #define FF_PROFILE_PRORES_4444 4
1724 #define FF_PROFILE_PRORES_XQ 5
1725 
1726 #define FF_PROFILE_ARIB_PROFILE_A 0
1727 #define FF_PROFILE_ARIB_PROFILE_C 1
1728 
1729 #define FF_PROFILE_KLVA_SYNC 0
1730 #define FF_PROFILE_KLVA_ASYNC 1
1731 
1732 #define FF_PROFILE_EVC_BASELINE 0
1733 #define FF_PROFILE_EVC_MAIN 1
1734 #endif
1735 
1736  /**
1737  * Encoding level descriptor.
1738  * - encoding: Set by user, corresponds to a specific level defined by the
1739  * codec, usually corresponding to the profile level, if not specified it
1740  * is set to FF_LEVEL_UNKNOWN.
1741  * - decoding: Set by libavcodec.
1742  * See AV_LEVEL_* in defs.h.
1743  */
1744  int level;
1745 #if FF_API_FF_PROFILE_LEVEL
1746  /** @deprecated The following define is deprecated; use AV_LEVEL_UNKOWN
1747  * in defs.h instead. */
1748 #define FF_LEVEL_UNKNOWN -99
1749 #endif
1750 
1751  /**
1752  * Skip loop filtering for selected frames.
1753  * - encoding: unused
1754  * - decoding: Set by user.
1755  */
1757 
1758  /**
1759  * Skip IDCT/dequantization for selected frames.
1760  * - encoding: unused
1761  * - decoding: Set by user.
1762  */
1764 
1765  /**
1766  * Skip decoding for selected frames.
1767  * - encoding: unused
1768  * - decoding: Set by user.
1769  */
1771 
1772  /**
1773  * Header containing style information for text subtitles.
1774  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
1775  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
1776  * the Format line following. It shouldn't include any Dialogue line.
1777  * - encoding: Set/allocated/freed by user (before avcodec_open2())
1778  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
1779  */
1782 
1783  /**
1784  * Audio only. The number of "priming" samples (padding) inserted by the
1785  * encoder at the beginning of the audio. I.e. this number of leading
1786  * decoded samples must be discarded by the caller to get the original audio
1787  * without leading padding.
1788  *
1789  * - decoding: unused
1790  * - encoding: Set by libavcodec. The timestamps on the output packets are
1791  * adjusted by the encoder so that they always refer to the
1792  * first sample of the data actually contained in the packet,
1793  * including any added padding. E.g. if the timebase is
1794  * 1/samplerate and the timestamp of the first input sample is
1795  * 0, the timestamp of the first output packet will be
1796  * -initial_padding.
1797  */
1799 
1800  /**
1801  * - decoding: For codecs that store a framerate value in the compressed
1802  * bitstream, the decoder may export it here. { 0, 1} when
1803  * unknown.
1804  * - encoding: May be used to signal the framerate of CFR content to an
1805  * encoder.
1806  */
1808 
1809  /**
1810  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
1811  * - encoding: unused.
1812  * - decoding: Set by libavcodec before calling get_format()
1813  */
1815 
1816  /**
1817  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are expressed.
1818  * - encoding: unused.
1819  * - decoding: set by user.
1820  */
1822 
1823  /**
1824  * AVCodecDescriptor
1825  * - encoding: unused.
1826  * - decoding: set by libavcodec.
1827  */
1829 
1830  /**
1831  * Current statistics for PTS correction.
1832  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
1833  * - encoding: unused
1834  */
1835  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
1836  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
1837  int64_t pts_correction_last_pts; /// PTS of the last frame
1838  int64_t pts_correction_last_dts; /// DTS of the last frame
1839 
1840  /**
1841  * Character encoding of the input subtitles file.
1842  * - decoding: set by user
1843  * - encoding: unused
1844  */
1846 
1847  /**
1848  * Subtitles character encoding mode. Formats or codecs might be adjusting
1849  * this setting (if they are doing the conversion themselves for instance).
1850  * - decoding: set by libavcodec
1851  * - encoding: unused
1852  */
1854 #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)
1855 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
1856 #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
1857 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
1858 
1859  /**
1860  * Skip processing alpha if supported by codec.
1861  * Note that if the format uses pre-multiplied alpha (common with VP6,
1862  * and recommended due to better video quality/compression)
1863  * the image will look as if alpha-blended onto a black background.
1864  * However for formats that do not use pre-multiplied alpha
1865  * there might be serious artefacts (though e.g. libswscale currently
1866  * assumes pre-multiplied alpha anyway).
1867  *
1868  * - decoding: set by user
1869  * - encoding: unused
1870  */
1872 
1873  /**
1874  * Number of samples to skip after a discontinuity
1875  * - decoding: unused
1876  * - encoding: set by libavcodec
1877  */
1879 
1880  /**
1881  * custom intra quantization matrix
1882  * - encoding: Set by user, can be NULL.
1883  * - decoding: unused.
1884  */
1886 
1887  /**
1888  * dump format separator.
1889  * can be ", " or "\n " or anything else
1890  * - encoding: Set by user.
1891  * - decoding: Set by user.
1892  */
1893  uint8_t *dump_separator;
1894 
1895  /**
1896  * ',' separated list of allowed decoders.
1897  * If NULL then all are allowed
1898  * - encoding: unused
1899  * - decoding: set by user
1900  */
1902 
1903  /**
1904  * Properties of the stream that gets decoded
1905  * - encoding: unused
1906  * - decoding: set by libavcodec
1907  */
1908  unsigned properties;
1909 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
1910 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
1911 #define FF_CODEC_PROPERTY_FILM_GRAIN 0x00000004
1912 
1913  /**
1914  * Additional data associated with the entire coded stream.
1915  *
1916  * - decoding: may be set by user before calling avcodec_open2().
1917  * - encoding: may be set by libavcodec after avcodec_open2().
1918  */
1921 
1922  /**
1923  * A reference to the AVHWFramesContext describing the input (for encoding)
1924  * or output (decoding) frames. The reference is set by the caller and
1925  * afterwards owned (and freed) by libavcodec - it should never be read by
1926  * the caller after being set.
1927  *
1928  * - decoding: This field should be set by the caller from the get_format()
1929  * callback. The previous reference (if any) will always be
1930  * unreffed by libavcodec before the get_format() call.
1931  *
1932  * If the default get_buffer2() is used with a hwaccel pixel
1933  * format, then this AVHWFramesContext will be used for
1934  * allocating the frame buffers.
1935  *
1936  * - encoding: For hardware encoders configured to use a hwaccel pixel
1937  * format, this field should be set by the caller to a reference
1938  * to the AVHWFramesContext describing input frames.
1939  * AVHWFramesContext.format must be equal to
1940  * AVCodecContext.pix_fmt.
1941  *
1942  * This field should be set before avcodec_open2() is called.
1943  */
1945 
1946  /**
1947  * Audio only. The amount of padding (in samples) appended by the encoder to
1948  * the end of the audio. I.e. this number of decoded samples must be
1949  * discarded by the caller from the end of the stream to get the original
1950  * audio without any trailing padding.
1951  *
1952  * - decoding: unused
1953  * - encoding: unused
1954  */
1956 
1957  /**
1958  * The number of pixels per image to maximally accept.
1959  *
1960  * - decoding: set by user
1961  * - encoding: set by user
1962  */
1963  int64_t max_pixels;
1964 
1965  /**
1966  * A reference to the AVHWDeviceContext describing the device which will
1967  * be used by a hardware encoder/decoder. The reference is set by the
1968  * caller and afterwards owned (and freed) by libavcodec.
1969  *
1970  * This should be used if either the codec device does not require
1971  * hardware frames or any that are used are to be allocated internally by
1972  * libavcodec. If the user wishes to supply any of the frames used as
1973  * encoder input or decoder output then hw_frames_ctx should be used
1974  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
1975  * field will be ignored while decoding the associated stream segment, but
1976  * may again be used on a following one after another get_format() call.
1977  *
1978  * For both encoders and decoders this field should be set before
1979  * avcodec_open2() is called and must not be written to thereafter.
1980  *
1981  * Note that some decoders may require this field to be set initially in
1982  * order to support hw_frames_ctx at all - in that case, all frames
1983  * contexts used must be created on the same device.
1984  */
1986 
1987  /**
1988  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
1989  * decoding (if active).
1990  * - encoding: unused
1991  * - decoding: Set by user (either before avcodec_open2(), or in the
1992  * AVCodecContext.get_format callback)
1993  */
1995 
1996  /**
1997  * Video decoding only. Certain video codecs support cropping, meaning that
1998  * only a sub-rectangle of the decoded frame is intended for display. This
1999  * option controls how cropping is handled by libavcodec.
2000  *
2001  * When set to 1 (the default), libavcodec will apply cropping internally.
2002  * I.e. it will modify the output frame width/height fields and offset the
2003  * data pointers (only by as much as possible while preserving alignment, or
2004  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
2005  * the frames output by the decoder refer only to the cropped area. The
2006  * crop_* fields of the output frames will be zero.
2007  *
2008  * When set to 0, the width/height fields of the output frames will be set
2009  * to the coded dimensions and the crop_* fields will describe the cropping
2010  * rectangle. Applying the cropping is left to the caller.
2011  *
2012  * @warning When hardware acceleration with opaque output frames is used,
2013  * libavcodec is unable to apply cropping from the top/left border.
2014  *
2015  * @note when this option is set to zero, the width/height fields of the
2016  * AVCodecContext and output AVFrames have different meanings. The codec
2017  * context fields store display dimensions (with the coded dimensions in
2018  * coded_width/height), while the frame fields store the coded dimensions
2019  * (with the display dimensions being determined by the crop_* fields).
2020  */
2022 
2023  /*
2024  * Video decoding only. Sets the number of extra hardware frames which
2025  * the decoder will allocate for use by the caller. This must be set
2026  * before avcodec_open2() is called.
2027  *
2028  * Some hardware decoders require all frames that they will use for
2029  * output to be defined in advance before decoding starts. For such
2030  * decoders, the hardware frame pool must therefore be of a fixed size.
2031  * The extra frames set here are on top of any number that the decoder
2032  * needs internally in order to operate normally (for example, frames
2033  * used as reference pictures).
2034  */
2036 
2037  /**
2038  * The percentage of damaged samples to discard a frame.
2039  *
2040  * - decoding: set by user
2041  * - encoding: unused
2042  */
2044 
2045  /**
2046  * The number of samples per frame to maximally accept.
2047  *
2048  * - decoding: set by user
2049  * - encoding: set by user
2050  */
2051  int64_t max_samples;
2052 
2053  /**
2054  * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
2055  * metadata exported in frame, packet, or coded stream side data by
2056  * decoders and encoders.
2057  *
2058  * - decoding: set by user
2059  * - encoding: set by user
2060  */
2062 
2063  /**
2064  * This callback is called at the beginning of each packet to get a data
2065  * buffer for it.
2066  *
2067  * The following field will be set in the packet before this callback is
2068  * called:
2069  * - size
2070  * This callback must use the above value to calculate the required buffer size,
2071  * which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
2072  *
2073  * In some specific cases, the encoder may not use the entire buffer allocated by this
2074  * callback. This will be reflected in the size value in the packet once returned by
2075  * avcodec_receive_packet().
2076  *
2077  * This callback must fill the following fields in the packet:
2078  * - data: alignment requirements for AVPacket apply, if any. Some architectures and
2079  * encoders may benefit from having aligned data.
2080  * - buf: must contain a pointer to an AVBufferRef structure. The packet's
2081  * data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
2082  * and av_buffer_ref().
2083  *
2084  * If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2085  * avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2086  * some other means.
2087  *
2088  * The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2089  * They may be used for example to hint what use the buffer may get after being
2090  * created.
2091  * Implementations of this callback may ignore flags they don't understand.
2092  * If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2093  * (read and/or written to if it is writable) later by libavcodec.
2094  *
2095  * This callback must be thread-safe, as when frame threading is used, it may
2096  * be called from multiple threads simultaneously.
2097  *
2098  * @see avcodec_default_get_encode_buffer()
2099  *
2100  * - encoding: Set by libavcodec, user can override.
2101  * - decoding: unused
2102  */
2104 
2105  /**
2106  * Audio channel layout.
2107  * - encoding: must be set by the caller, to one of AVCodec.ch_layouts.
2108  * - decoding: may be set by the caller if known e.g. from the container.
2109  * The decoder can then override during decoding as needed.
2110  */
2112 
2113  /**
2114  * Frame counter, set by libavcodec.
2115  *
2116  * - decoding: total number of frames returned from the decoder so far.
2117  * - encoding: total number of frames passed to the encoder so far.
2118  *
2119  * @note the counter is not incremented if encoding/decoding resulted in
2120  * an error.
2121  */
2122  int64_t frame_num;
2123 } AVCodecContext;
2124 
2125 /**
2126  * @defgroup lavc_hwaccel AVHWAccel
2127  *
2128  * @note Nothing in this structure should be accessed by the user. At some
2129  * point in future it will not be externally visible at all.
2130  *
2131  * @{
2132  */
2133 typedef struct AVHWAccel {
2134  /**
2135  * Name of the hardware accelerated codec.
2136  * The name is globally unique among encoders and among decoders (but an
2137  * encoder and a decoder can share the same name).
2138  */
2139  const char *name;
2140 
2141  /**
2142  * Type of codec implemented by the hardware accelerator.
2143  *
2144  * See AVMEDIA_TYPE_xxx
2145  */
2147 
2148  /**
2149  * Codec implemented by the hardware accelerator.
2150  *
2151  * See AV_CODEC_ID_xxx
2152  */
2154 
2155  /**
2156  * Supported pixel format.
2157  *
2158  * Only hardware accelerated formats are supported here.
2159  */
2161 
2162  /**
2163  * Hardware accelerated codec capabilities.
2164  * see AV_HWACCEL_CODEC_CAP_*
2165  */
2167 } AVHWAccel;
2168 
2169 /**
2170  * HWAccel is experimental and is thus avoided in favor of non experimental
2171  * codecs
2172  */
2173 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2174 
2175 /**
2176  * Hardware acceleration should be used for decoding even if the codec level
2177  * used is unknown or higher than the maximum supported level reported by the
2178  * hardware driver.
2179  *
2180  * It's generally a good idea to pass this flag unless you have a specific
2181  * reason not to, as hardware tends to under-report supported levels.
2182  */
2183 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2184 
2185 /**
2186  * Hardware acceleration can output YUV pixel formats with a different chroma
2187  * sampling than 4:2:0 and/or other than 8 bits per component.
2188  */
2189 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2190 
2191 /**
2192  * Hardware acceleration should still be attempted for decoding when the
2193  * codec profile does not match the reported capabilities of the hardware.
2194  *
2195  * For example, this can be used to try to decode baseline profile H.264
2196  * streams in hardware - it will often succeed, because many streams marked
2197  * as baseline profile actually conform to constrained baseline profile.
2198  *
2199  * @warning If the stream is actually not supported then the behaviour is
2200  * undefined, and may include returning entirely incorrect output
2201  * while indicating success.
2202  */
2203 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2204 
2205 /**
2206  * Some hardware decoders (namely nvdec) can either output direct decoder
2207  * surfaces, or make an on-device copy and return said copy.
2208  * There is a hard limit on how many decoder surfaces there can be, and it
2209  * cannot be accurately guessed ahead of time.
2210  * For some processing chains, this can be okay, but others will run into the
2211  * limit and in turn produce very confusing errors that require fine tuning of
2212  * more or less obscure options by the user, or in extreme cases cannot be
2213  * resolved at all without inserting an avfilter that forces a copy.
2214  *
2215  * Thus, the hwaccel will by default make a copy for safety and resilience.
2216  * If a users really wants to minimize the amount of copies, they can set this
2217  * flag and ensure their processing chain does not exhaust the surface pool.
2218  */
2219 #define AV_HWACCEL_FLAG_UNSAFE_OUTPUT (1 << 3)
2220 
2221 /**
2222  * @}
2223  */
2224 
2227 
2228  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2229 
2230  /**
2231  * Plain text, the text field must be set by the decoder and is
2232  * authoritative. ass and pict fields may contain approximations.
2233  */
2235 
2236  /**
2237  * Formatted text, the ass field must be set by the decoder and is
2238  * authoritative. pict and text fields may contain approximations.
2239  */
2241 };
2242 
2243 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
2244 
2245 typedef struct AVSubtitleRect {
2246  int x; ///< top left corner of pict, undefined when pict is not set
2247  int y; ///< top left corner of pict, undefined when pict is not set
2248  int w; ///< width of pict, undefined when pict is not set
2249  int h; ///< height of pict, undefined when pict is not set
2250  int nb_colors; ///< number of colors in pict, undefined when pict is not set
2251 
2252  /**
2253  * data+linesize for the bitmap of this subtitle.
2254  * Can be set for text/ass as well once they are rendered.
2255  */
2256  uint8_t *data[4];
2257  int linesize[4];
2258 
2260 
2261  char *text; ///< 0 terminated plain UTF-8 text
2262 
2263  /**
2264  * 0 terminated ASS/SSA compatible event line.
2265  * The presentation of this is unaffected by the other values in this
2266  * struct.
2267  */
2268  char *ass;
2269 
2270  int flags;
2271 } AVSubtitleRect;
2272 
2273 typedef struct AVSubtitle {
2274  uint16_t format; /* 0 = graphics */
2275  uint32_t start_display_time; /* relative to packet pts, in ms */
2276  uint32_t end_display_time; /* relative to packet pts, in ms */
2277  unsigned num_rects;
2279  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2280 } AVSubtitle;
2281 
2282 /**
2283  * Return the LIBAVCODEC_VERSION_INT constant.
2284  */
2285 unsigned avcodec_version(void);
2286 
2287 /**
2288  * Return the libavcodec build-time configuration.
2289  */
2290 const char *avcodec_configuration(void);
2291 
2292 /**
2293  * Return the libavcodec license.
2294  */
2295 const char *avcodec_license(void);
2296 
2297 /**
2298  * Allocate an AVCodecContext and set its fields to default values. The
2299  * resulting struct should be freed with avcodec_free_context().
2300  *
2301  * @param codec if non-NULL, allocate private data and initialize defaults
2302  * for the given codec. It is illegal to then call avcodec_open2()
2303  * with a different codec.
2304  * If NULL, then the codec-specific defaults won't be initialized,
2305  * which may result in suboptimal default settings (this is
2306  * important mainly for encoders, e.g. libx264).
2307  *
2308  * @return An AVCodecContext filled with default values or NULL on failure.
2309  */
2311 
2312 /**
2313  * Free the codec context and everything associated with it and write NULL to
2314  * the provided pointer.
2315  */
2316 void avcodec_free_context(AVCodecContext **avctx);
2317 
2318 /**
2319  * Get the AVClass for AVCodecContext. It can be used in combination with
2320  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2321  *
2322  * @see av_opt_find().
2323  */
2324 const AVClass *avcodec_get_class(void);
2325 
2326 /**
2327  * Get the AVClass for AVSubtitleRect. It can be used in combination with
2328  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2329  *
2330  * @see av_opt_find().
2331  */
2333 
2334 /**
2335  * Fill the parameters struct based on the values from the supplied codec
2336  * context. Any allocated fields in par are freed and replaced with duplicates
2337  * of the corresponding fields in codec.
2338  *
2339  * @return >= 0 on success, a negative AVERROR code on failure
2340  */
2342  const AVCodecContext *codec);
2343 
2344 /**
2345  * Fill the codec context based on the values from the supplied codec
2346  * parameters. Any allocated fields in codec that have a corresponding field in
2347  * par are freed and replaced with duplicates of the corresponding field in par.
2348  * Fields in codec that do not have a counterpart in par are not touched.
2349  *
2350  * @return >= 0 on success, a negative AVERROR code on failure.
2351  */
2353  const struct AVCodecParameters *par);
2354 
2355 /**
2356  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2357  * function the context has to be allocated with avcodec_alloc_context3().
2358  *
2359  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2360  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2361  * retrieving a codec.
2362  *
2363  * Depending on the codec, you might need to set options in the codec context
2364  * also for decoding (e.g. width, height, or the pixel or audio sample format in
2365  * the case the information is not available in the bitstream, as when decoding
2366  * raw audio or video).
2367  *
2368  * Options in the codec context can be set either by setting them in the options
2369  * AVDictionary, or by setting the values in the context itself, directly or by
2370  * using the av_opt_set() API before calling this function.
2371  *
2372  * Example:
2373  * @code
2374  * av_dict_set(&opts, "b", "2.5M", 0);
2375  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2376  * if (!codec)
2377  * exit(1);
2378  *
2379  * context = avcodec_alloc_context3(codec);
2380  *
2381  * if (avcodec_open2(context, codec, opts) < 0)
2382  * exit(1);
2383  * @endcode
2384  *
2385  * In the case AVCodecParameters are available (e.g. when demuxing a stream
2386  * using libavformat, and accessing the AVStream contained in the demuxer), the
2387  * codec parameters can be copied to the codec context using
2388  * avcodec_parameters_to_context(), as in the following example:
2389  *
2390  * @code
2391  * AVStream *stream = ...;
2392  * context = avcodec_alloc_context3(codec);
2393  * if (avcodec_parameters_to_context(context, stream->codecpar) < 0)
2394  * exit(1);
2395  * if (avcodec_open2(context, codec, NULL) < 0)
2396  * exit(1);
2397  * @endcode
2398  *
2399  * @note Always call this function before using decoding routines (such as
2400  * @ref avcodec_receive_frame()).
2401  *
2402  * @param avctx The context to initialize.
2403  * @param codec The codec to open this context for. If a non-NULL codec has been
2404  * previously passed to avcodec_alloc_context3() or
2405  * for this context, then this parameter MUST be either NULL or
2406  * equal to the previously passed codec.
2407  * @param options A dictionary filled with AVCodecContext and codec-private
2408  * options, which are set on top of the options already set in
2409  * avctx, can be NULL. On return this object will be filled with
2410  * options that were not found in the avctx codec context.
2411  *
2412  * @return zero on success, a negative value on error
2413  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2414  * av_dict_set(), av_opt_set(), av_opt_find(), avcodec_parameters_to_context()
2415  */
2416 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2417 
2418 #if FF_API_AVCODEC_CLOSE
2419 /**
2420  * Close a given AVCodecContext and free all the data associated with it
2421  * (but not the AVCodecContext itself).
2422  *
2423  * Calling this function on an AVCodecContext that hasn't been opened will free
2424  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2425  * codec. Subsequent calls will do nothing.
2426  *
2427  * @deprecated Do not use this function. Use avcodec_free_context() to destroy a
2428  * codec context (either open or closed). Opening and closing a codec context
2429  * multiple times is not supported anymore -- use multiple codec contexts
2430  * instead.
2431  */
2433 int avcodec_close(AVCodecContext *avctx);
2434 #endif
2435 
2436 /**
2437  * Free all allocated data in the given subtitle struct.
2438  *
2439  * @param sub AVSubtitle to free.
2440  */
2441 void avsubtitle_free(AVSubtitle *sub);
2442 
2443 /**
2444  * @}
2445  */
2446 
2447 /**
2448  * @addtogroup lavc_decoding
2449  * @{
2450  */
2451 
2452 /**
2453  * The default callback for AVCodecContext.get_buffer2(). It is made public so
2454  * it can be called by custom get_buffer2() implementations for decoders without
2455  * AV_CODEC_CAP_DR1 set.
2456  */
2458 
2459 /**
2460  * The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2461  * it can be called by custom get_encode_buffer() implementations for encoders without
2462  * AV_CODEC_CAP_DR1 set.
2463  */
2465 
2466 /**
2467  * Modify width and height values so that they will result in a memory
2468  * buffer that is acceptable for the codec if you do not use any horizontal
2469  * padding.
2470  *
2471  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2472  */
2474 
2475 /**
2476  * Modify width and height values so that they will result in a memory
2477  * buffer that is acceptable for the codec if you also ensure that all
2478  * line sizes are a multiple of the respective linesize_align[i].
2479  *
2480  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2481  */
2483  int linesize_align[AV_NUM_DATA_POINTERS]);
2484 
2485 #ifdef FF_API_AVCODEC_CHROMA_POS
2486 /**
2487  * Converts AVChromaLocation to swscale x/y chroma position.
2488  *
2489  * The positions represent the chroma (0,0) position in a coordinates system
2490  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2491  *
2492  * @param xpos horizontal chroma sample position
2493  * @param ypos vertical chroma sample position
2494  * @deprecated Use av_chroma_location_enum_to_pos() instead.
2495  */
2497 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
2498 
2499 /**
2500  * Converts swscale x/y chroma position to AVChromaLocation.
2501  *
2502  * The positions represent the chroma (0,0) position in a coordinates system
2503  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2504  *
2505  * @param xpos horizontal chroma sample position
2506  * @param ypos vertical chroma sample position
2507  * @deprecated Use av_chroma_location_pos_to_enum() instead.
2508  */
2510 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
2511 #endif
2512 
2513 /**
2514  * Decode a subtitle message.
2515  * Return a negative value on error, otherwise return the number of bytes used.
2516  * If no subtitle could be decompressed, got_sub_ptr is zero.
2517  * Otherwise, the subtitle is stored in *sub.
2518  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
2519  * simplicity, because the performance difference is expected to be negligible
2520  * and reusing a get_buffer written for video codecs would probably perform badly
2521  * due to a potentially very different allocation pattern.
2522  *
2523  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2524  * and output. This means that for some packets they will not immediately
2525  * produce decoded output and need to be flushed at the end of decoding to get
2526  * all the decoded data. Flushing is done by calling this function with packets
2527  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2528  * returning subtitles. It is safe to flush even those decoders that are not
2529  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
2530  *
2531  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2532  * before packets may be fed to the decoder.
2533  *
2534  * @param avctx the codec context
2535  * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
2536  * must be freed with avsubtitle_free if *got_sub_ptr is set.
2537  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
2538  * @param[in] avpkt The input AVPacket containing the input buffer.
2539  */
2541  int *got_sub_ptr, const AVPacket *avpkt);
2542 
2543 /**
2544  * Supply raw packet data as input to a decoder.
2545  *
2546  * Internally, this call will copy relevant AVCodecContext fields, which can
2547  * influence decoding per-packet, and apply them when the packet is actually
2548  * decoded. (For example AVCodecContext.skip_frame, which might direct the
2549  * decoder to drop the frame contained by the packet sent with this function.)
2550  *
2551  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2552  * larger than the actual read bytes because some optimized bitstream
2553  * readers read 32 or 64 bits at once and could read over the end.
2554  *
2555  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2556  * before packets may be fed to the decoder.
2557  *
2558  * @param avctx codec context
2559  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
2560  * frame, or several complete audio frames.
2561  * Ownership of the packet remains with the caller, and the
2562  * decoder will not write to the packet. The decoder may create
2563  * a reference to the packet data (or copy it if the packet is
2564  * not reference-counted).
2565  * Unlike with older APIs, the packet is always fully consumed,
2566  * and if it contains multiple frames (e.g. some audio codecs),
2567  * will require you to call avcodec_receive_frame() multiple
2568  * times afterwards before you can send a new packet.
2569  * It can be NULL (or an AVPacket with data set to NULL and
2570  * size set to 0); in this case, it is considered a flush
2571  * packet, which signals the end of the stream. Sending the
2572  * first flush packet will return success. Subsequent ones are
2573  * unnecessary and will return AVERROR_EOF. If the decoder
2574  * still has frames buffered, it will return them after sending
2575  * a flush packet.
2576  *
2577  * @retval 0 success
2578  * @retval AVERROR(EAGAIN) input is not accepted in the current state - user
2579  * must read output with avcodec_receive_frame() (once
2580  * all output is read, the packet should be resent,
2581  * and the call will not fail with EAGAIN).
2582  * @retval AVERROR_EOF the decoder has been flushed, and no new packets can be
2583  * sent to it (also returned if more than 1 flush
2584  * packet is sent)
2585  * @retval AVERROR(EINVAL) codec not opened, it is an encoder, or requires flush
2586  * @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
2587  * @retval "another negative error code" legitimate decoding errors
2588  */
2589 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
2590 
2591 /**
2592  * Return decoded output data from a decoder or encoder (when the
2593  * @ref AV_CODEC_FLAG_RECON_FRAME flag is used).
2594  *
2595  * @param avctx codec context
2596  * @param frame This will be set to a reference-counted video or audio
2597  * frame (depending on the decoder type) allocated by the
2598  * codec. Note that the function will always call
2599  * av_frame_unref(frame) before doing anything else.
2600  *
2601  * @retval 0 success, a frame was returned
2602  * @retval AVERROR(EAGAIN) output is not available in this state - user must
2603  * try to send new input
2604  * @retval AVERROR_EOF the codec has been fully flushed, and there will be
2605  * no more output frames
2606  * @retval AVERROR(EINVAL) codec not opened, or it is an encoder without the
2607  * @ref AV_CODEC_FLAG_RECON_FRAME flag enabled
2608  * @retval "other negative error code" legitimate decoding errors
2609  */
2611 
2612 /**
2613  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
2614  * to retrieve buffered output packets.
2615  *
2616  * @param avctx codec context
2617  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
2618  * Ownership of the frame remains with the caller, and the
2619  * encoder will not write to the frame. The encoder may create
2620  * a reference to the frame data (or copy it if the frame is
2621  * not reference-counted).
2622  * It can be NULL, in which case it is considered a flush
2623  * packet. This signals the end of the stream. If the encoder
2624  * still has packets buffered, it will return them after this
2625  * call. Once flushing mode has been entered, additional flush
2626  * packets are ignored, and sending frames will return
2627  * AVERROR_EOF.
2628  *
2629  * For audio:
2630  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
2631  * can have any number of samples.
2632  * If it is not set, frame->nb_samples must be equal to
2633  * avctx->frame_size for all frames except the last.
2634  * The final frame may be smaller than avctx->frame_size.
2635  * @retval 0 success
2636  * @retval AVERROR(EAGAIN) input is not accepted in the current state - user must
2637  * read output with avcodec_receive_packet() (once all
2638  * output is read, the packet should be resent, and the
2639  * call will not fail with EAGAIN).
2640  * @retval AVERROR_EOF the encoder has been flushed, and no new frames can
2641  * be sent to it
2642  * @retval AVERROR(EINVAL) codec not opened, it is a decoder, or requires flush
2643  * @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
2644  * @retval "another negative error code" legitimate encoding errors
2645  */
2646 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
2647 
2648 /**
2649  * Read encoded data from the encoder.
2650  *
2651  * @param avctx codec context
2652  * @param avpkt This will be set to a reference-counted packet allocated by the
2653  * encoder. Note that the function will always call
2654  * av_packet_unref(avpkt) before doing anything else.
2655  * @retval 0 success
2656  * @retval AVERROR(EAGAIN) output is not available in the current state - user must
2657  * try to send input
2658  * @retval AVERROR_EOF the encoder has been fully flushed, and there will be no
2659  * more output packets
2660  * @retval AVERROR(EINVAL) codec not opened, or it is a decoder
2661  * @retval "another negative error code" legitimate encoding errors
2662  */
2663 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
2664 
2665 /**
2666  * Create and return a AVHWFramesContext with values adequate for hardware
2667  * decoding. This is meant to get called from the get_format callback, and is
2668  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
2669  * This API is for decoding with certain hardware acceleration modes/APIs only.
2670  *
2671  * The returned AVHWFramesContext is not initialized. The caller must do this
2672  * with av_hwframe_ctx_init().
2673  *
2674  * Calling this function is not a requirement, but makes it simpler to avoid
2675  * codec or hardware API specific details when manually allocating frames.
2676  *
2677  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
2678  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
2679  * it unnecessary to call this function or having to care about
2680  * AVHWFramesContext initialization at all.
2681  *
2682  * There are a number of requirements for calling this function:
2683  *
2684  * - It must be called from get_format with the same avctx parameter that was
2685  * passed to get_format. Calling it outside of get_format is not allowed, and
2686  * can trigger undefined behavior.
2687  * - The function is not always supported (see description of return values).
2688  * Even if this function returns successfully, hwaccel initialization could
2689  * fail later. (The degree to which implementations check whether the stream
2690  * is actually supported varies. Some do this check only after the user's
2691  * get_format callback returns.)
2692  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
2693  * user decides to use a AVHWFramesContext prepared with this API function,
2694  * the user must return the same hw_pix_fmt from get_format.
2695  * - The device_ref passed to this function must support the given hw_pix_fmt.
2696  * - After calling this API function, it is the user's responsibility to
2697  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
2698  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
2699  * before returning from get_format (this is implied by the normal
2700  * AVCodecContext.hw_frames_ctx API rules).
2701  * - The AVHWFramesContext parameters may change every time time get_format is
2702  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
2703  * you are inherently required to go through this process again on every
2704  * get_format call.
2705  * - It is perfectly possible to call this function without actually using
2706  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
2707  * previously initialized AVHWFramesContext, and calling this API function
2708  * only to test whether the required frame parameters have changed.
2709  * - Fields that use dynamically allocated values of any kind must not be set
2710  * by the user unless setting them is explicitly allowed by the documentation.
2711  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
2712  * the new free callback must call the potentially set previous free callback.
2713  * This API call may set any dynamically allocated fields, including the free
2714  * callback.
2715  *
2716  * The function will set at least the following fields on AVHWFramesContext
2717  * (potentially more, depending on hwaccel API):
2718  *
2719  * - All fields set by av_hwframe_ctx_alloc().
2720  * - Set the format field to hw_pix_fmt.
2721  * - Set the sw_format field to the most suited and most versatile format. (An
2722  * implication is that this will prefer generic formats over opaque formats
2723  * with arbitrary restrictions, if possible.)
2724  * - Set the width/height fields to the coded frame size, rounded up to the
2725  * API-specific minimum alignment.
2726  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
2727  * field to the number of maximum reference surfaces possible with the codec,
2728  * plus 1 surface for the user to work (meaning the user can safely reference
2729  * at most 1 decoded surface at a time), plus additional buffering introduced
2730  * by frame threading. If the hwaccel does not require pre-allocation, the
2731  * field is left to 0, and the decoder will allocate new surfaces on demand
2732  * during decoding.
2733  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
2734  * hardware API.
2735  *
2736  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
2737  * with basic frame parameters set.
2738  *
2739  * The function is stateless, and does not change the AVCodecContext or the
2740  * device_ref AVHWDeviceContext.
2741  *
2742  * @param avctx The context which is currently calling get_format, and which
2743  * implicitly contains all state needed for filling the returned
2744  * AVHWFramesContext properly.
2745  * @param device_ref A reference to the AVHWDeviceContext describing the device
2746  * which will be used by the hardware decoder.
2747  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
2748  * @param out_frames_ref On success, set to a reference to an _uninitialized_
2749  * AVHWFramesContext, created from the given device_ref.
2750  * Fields will be set to values required for decoding.
2751  * Not changed if an error is returned.
2752  * @return zero on success, a negative value on error. The following error codes
2753  * have special semantics:
2754  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
2755  * is always manual, or it is a decoder which does not
2756  * support setting AVCodecContext.hw_frames_ctx at all,
2757  * or it is a software format.
2758  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
2759  * this configuration, or the device_ref is not supported
2760  * for the hwaccel referenced by hw_pix_fmt.
2761  */
2763  AVBufferRef *device_ref,
2765  AVBufferRef **out_frames_ref);
2766 
2767 
2768 
2769 /**
2770  * @defgroup lavc_parsing Frame parsing
2771  * @{
2772  */
2773 
2776  AV_PICTURE_STRUCTURE_TOP_FIELD, ///< coded as top field
2777  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, ///< coded as bottom field
2778  AV_PICTURE_STRUCTURE_FRAME, ///< coded as frame
2779 };
2780 
2781 typedef struct AVCodecParserContext {
2782  void *priv_data;
2783  const struct AVCodecParser *parser;
2784  int64_t frame_offset; /* offset of the current frame */
2785  int64_t cur_offset; /* current offset
2786  (incremented by each av_parser_parse()) */
2787  int64_t next_frame_offset; /* offset of the next frame */
2788  /* video info */
2789  int pict_type; /* XXX: Put it back in AVCodecContext. */
2790  /**
2791  * This field is used for proper frame duration computation in lavf.
2792  * It signals, how much longer the frame duration of the current frame
2793  * is compared to normal frame duration.
2794  *
2795  * frame_duration = (1 + repeat_pict) * time_base
2796  *
2797  * It is used by codecs like H.264 to display telecined material.
2798  */
2799  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
2800  int64_t pts; /* pts of the current frame */
2801  int64_t dts; /* dts of the current frame */
2802 
2803  /* private data */
2804  int64_t last_pts;
2805  int64_t last_dts;
2807 
2808 #define AV_PARSER_PTS_NB 4
2813 
2814  int flags;
2815 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
2816 #define PARSER_FLAG_ONCE 0x0002
2817 /// Set if the parser has a valid file offset
2818 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
2819 #define PARSER_FLAG_USE_CODEC_TS 0x1000
2820 
2821  int64_t offset; ///< byte offset from starting packet start
2823 
2824  /**
2825  * Set by parser to 1 for key frames and 0 for non-key frames.
2826  * It is initialized to -1, so if the parser doesn't set this flag,
2827  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
2828  * will be used.
2829  */
2831 
2832  // Timestamp generation support:
2833  /**
2834  * Synchronization point for start of timestamp generation.
2835  *
2836  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
2837  * (default).
2838  *
2839  * For example, this corresponds to presence of H.264 buffering period
2840  * SEI message.
2841  */
2843 
2844  /**
2845  * Offset of the current timestamp against last timestamp sync point in
2846  * units of AVCodecContext.time_base.
2847  *
2848  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2849  * contain a valid timestamp offset.
2850  *
2851  * Note that the timestamp of sync point has usually a nonzero
2852  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
2853  * the next frame after timestamp sync point will be usually 1.
2854  *
2855  * For example, this corresponds to H.264 cpb_removal_delay.
2856  */
2858 
2859  /**
2860  * Presentation delay of current frame in units of AVCodecContext.time_base.
2861  *
2862  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2863  * contain valid non-negative timestamp delta (presentation time of a frame
2864  * must not lie in the past).
2865  *
2866  * This delay represents the difference between decoding and presentation
2867  * time of the frame.
2868  *
2869  * For example, this corresponds to H.264 dpb_output_delay.
2870  */
2872 
2873  /**
2874  * Position of the packet in file.
2875  *
2876  * Analogous to cur_frame_pts/dts
2877  */
2879 
2880  /**
2881  * Byte position of currently parsed frame in stream.
2882  */
2883  int64_t pos;
2884 
2885  /**
2886  * Previous frame byte position.
2887  */
2888  int64_t last_pos;
2889 
2890  /**
2891  * Duration of the current frame.
2892  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
2893  * For all other types, this is in units of AVCodecContext.time_base.
2894  */
2896 
2898 
2899  /**
2900  * Indicate whether a picture is coded as a frame, top field or bottom field.
2901  *
2902  * For example, H.264 field_pic_flag equal to 0 corresponds to
2903  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
2904  * equal to 1 and bottom_field_flag equal to 0 corresponds to
2905  * AV_PICTURE_STRUCTURE_TOP_FIELD.
2906  */
2908 
2909  /**
2910  * Picture number incremented in presentation or output order.
2911  * This field may be reinitialized at the first picture of a new sequence.
2912  *
2913  * For example, this corresponds to H.264 PicOrderCnt.
2914  */
2916 
2917  /**
2918  * Dimensions of the decoded video intended for presentation.
2919  */
2920  int width;
2921  int height;
2922 
2923  /**
2924  * Dimensions of the coded video.
2925  */
2928 
2929  /**
2930  * The format of the coded data, corresponds to enum AVPixelFormat for video
2931  * and for enum AVSampleFormat for audio.
2932  *
2933  * Note that a decoder can have considerable freedom in how exactly it
2934  * decodes the data, so the format reported here might be different from the
2935  * one returned by a decoder.
2936  */
2937  int format;
2939 
2940 typedef struct AVCodecParser {
2941  int codec_ids[7]; /* several codec IDs are permitted */
2944  /* This callback never returns an error, a negative value means that
2945  * the frame start was in a previous packet. */
2947  AVCodecContext *avctx,
2948  const uint8_t **poutbuf, int *poutbuf_size,
2949  const uint8_t *buf, int buf_size);
2951  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
2952 } AVCodecParser;
2953 
2954 /**
2955  * Iterate over all registered codec parsers.
2956  *
2957  * @param opaque a pointer where libavcodec will store the iteration state. Must
2958  * point to NULL to start the iteration.
2959  *
2960  * @return the next registered codec parser or NULL when the iteration is
2961  * finished
2962  */
2963 const AVCodecParser *av_parser_iterate(void **opaque);
2964 
2966 
2967 /**
2968  * Parse a packet.
2969  *
2970  * @param s parser context.
2971  * @param avctx codec context.
2972  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
2973  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
2974  * @param buf input buffer.
2975  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
2976  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
2977  To signal EOF, this should be 0 (so that the last frame
2978  can be output).
2979  * @param pts input presentation timestamp.
2980  * @param dts input decoding timestamp.
2981  * @param pos input byte position in stream.
2982  * @return the number of bytes of the input bitstream used.
2983  *
2984  * Example:
2985  * @code
2986  * while(in_len){
2987  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
2988  * in_data, in_len,
2989  * pts, dts, pos);
2990  * in_data += len;
2991  * in_len -= len;
2992  *
2993  * if(size)
2994  * decode_frame(data, size);
2995  * }
2996  * @endcode
2997  */
2999  AVCodecContext *avctx,
3000  uint8_t **poutbuf, int *poutbuf_size,
3001  const uint8_t *buf, int buf_size,
3002  int64_t pts, int64_t dts,
3003  int64_t pos);
3004 
3006 
3007 /**
3008  * @}
3009  * @}
3010  */
3011 
3012 /**
3013  * @addtogroup lavc_encoding
3014  * @{
3015  */
3016 
3017 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3018  const AVSubtitle *sub);
3019 
3020 
3021 /**
3022  * @}
3023  */
3024 
3025 /**
3026  * @defgroup lavc_misc Utility functions
3027  * @ingroup libavc
3028  *
3029  * Miscellaneous utility functions related to both encoding and decoding
3030  * (or neither).
3031  * @{
3032  */
3033 
3034 /**
3035  * @defgroup lavc_misc_pixfmt Pixel formats
3036  *
3037  * Functions for working with pixel formats.
3038  * @{
3039  */
3040 
3041 /**
3042  * Return a value representing the fourCC code associated to the
3043  * pixel format pix_fmt, or 0 if no associated fourCC code can be
3044  * found.
3045  */
3047 
3048 /**
3049  * Find the best pixel format to convert to given a certain source pixel
3050  * format. When converting from one pixel format to another, information loss
3051  * may occur. For example, when converting from RGB24 to GRAY, the color
3052  * information will be lost. Similarly, other losses occur when converting from
3053  * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
3054  * the given pixel formats should be used to suffer the least amount of loss.
3055  * The pixel formats from which it chooses one, are determined by the
3056  * pix_fmt_list parameter.
3057  *
3058  *
3059  * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
3060  * @param[in] src_pix_fmt source pixel format
3061  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
3062  * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
3063  * @return The best pixel format to convert to or -1 if none was found.
3064  */
3065 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
3066  enum AVPixelFormat src_pix_fmt,
3067  int has_alpha, int *loss_ptr);
3068 
3070 
3071 /**
3072  * @}
3073  */
3074 
3075 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
3076 
3077 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
3078 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
3079 //FIXME func typedef
3080 
3081 /**
3082  * Fill AVFrame audio data and linesize pointers.
3083  *
3084  * The buffer buf must be a preallocated buffer with a size big enough
3085  * to contain the specified samples amount. The filled AVFrame data
3086  * pointers will point to this buffer.
3087  *
3088  * AVFrame extended_data channel pointers are allocated if necessary for
3089  * planar audio.
3090  *
3091  * @param frame the AVFrame
3092  * frame->nb_samples must be set prior to calling the
3093  * function. This function fills in frame->data,
3094  * frame->extended_data, frame->linesize[0].
3095  * @param nb_channels channel count
3096  * @param sample_fmt sample format
3097  * @param buf buffer to use for frame data
3098  * @param buf_size size of buffer
3099  * @param align plane size sample alignment (0 = default)
3100  * @return >=0 on success, negative error code on failure
3101  * @todo return the size in bytes required to store the samples in
3102  * case of success, at the next libavutil bump
3103  */
3104 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
3105  enum AVSampleFormat sample_fmt, const uint8_t *buf,
3106  int buf_size, int align);
3107 
3108 /**
3109  * Reset the internal codec state / flush internal buffers. Should be called
3110  * e.g. when seeking or when switching to a different stream.
3111  *
3112  * @note for decoders, this function just releases any references the decoder
3113  * might keep internally, but the caller's references remain valid.
3114  *
3115  * @note for encoders, this function will only do something if the encoder
3116  * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3117  * will drain any remaining packets, and can then be re-used for a different
3118  * stream (as opposed to sending a null frame which will leave the encoder
3119  * in a permanent EOF state after draining). This can be desirable if the
3120  * cost of tearing down and replacing the encoder instance is high.
3121  */
3123 
3124 /**
3125  * Return audio frame duration.
3126  *
3127  * @param avctx codec context
3128  * @param frame_bytes size of the frame, or 0 if unknown
3129  * @return frame duration, in samples, if known. 0 if not able to
3130  * determine.
3131  */
3132 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
3133 
3134 /* memory */
3135 
3136 /**
3137  * Same behaviour av_fast_malloc but the buffer has additional
3138  * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
3139  *
3140  * In addition the whole buffer will initially and after resizes
3141  * be 0-initialized so that no uninitialized data will ever appear.
3142  */
3143 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
3144 
3145 /**
3146  * Same behaviour av_fast_padded_malloc except that buffer will always
3147  * be 0-initialized after call.
3148  */
3149 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
3150 
3151 /**
3152  * @return a positive value if s is open (i.e. avcodec_open2() was called on it
3153  * with no corresponding avcodec_close()), 0 otherwise.
3154  */
3156 
3157 /**
3158  * @}
3159  */
3160 
3161 #endif /* AVCODEC_AVCODEC_H */
AVSubtitle
Definition: avcodec.h:2273
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:190
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1096
AVCodecContext::hwaccel
const struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:1439
AVCodec
AVCodec.
Definition: codec.h:187
AVCodecContext::hwaccel_context
void * hwaccel_context
Legacy hardware accelerator context.
Definition: avcodec.h:1463
hw_pix_fmt
static enum AVPixelFormat hw_pix_fmt
Definition: hw_decode.c:45
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:366
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
AVCodecParserContext::pts
int64_t pts
Definition: avcodec.h:2800
AVCodecContext::log_level_offset
int log_level_offset
Definition: avcodec.h:451
AVCodecContext::keyint_min
int keyint_min
minimum GOP size
Definition: avcodec.h:998
avcodec_receive_packet
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:556
AVCodecContext::workaround_bugs
int workaround_bugs
Work around bugs in encoders which sometimes cannot be detected automatically.
Definition: avcodec.h:1345
AVSubtitle::rects
AVSubtitleRect ** rects
Definition: avcodec.h:2278
AVCodecContext::get_format
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Callback to negotiate the pixel format.
Definition: avcodec.h:716
AVCodecParserContext::dts_sync_point
int dts_sync_point
Synchronization point for start of timestamp generation.
Definition: avcodec.h:2842
AVCodecContext::audio_service_type
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:1151
AVCodecContext::colorspace
enum AVColorSpace colorspace
YUV colorspace type.
Definition: avcodec.h:1033
AVColorTransferCharacteristic
AVColorTransferCharacteristic
Color Transfer Characteristic.
Definition: pixfmt.h:584
AVCodecContext::av_class
const AVClass * av_class
information on struct for av_log
Definition: avcodec.h:450
AVCodecParserContext::pict_type
int pict_type
Definition: avcodec.h:2789
AVFieldOrder
AVFieldOrder
Definition: defs.h:198
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1068
AVCodecContext::rc_min_rate
int64_t rc_min_rate
minimum bitrate
Definition: avcodec.h:1295
AVCodecParserContext::output_picture_number
int output_picture_number
Picture number incremented in presentation or output order.
Definition: avcodec.h:2915
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
AVHWAccel::type
enum AVMediaType type
Type of codec implemented by the hardware accelerator.
Definition: avcodec.h:2146
AV_PICTURE_STRUCTURE_UNKNOWN
@ AV_PICTURE_STRUCTURE_UNKNOWN
unknown
Definition: avcodec.h:2775
AVCodecParserContext::duration
int duration
Duration of the current frame.
Definition: avcodec.h:2895
AVCodecContext::err_recognition
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1416
avcodec_string
void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
Definition: avcodec.c:515
AVCodecContext::codec_descriptor
const struct AVCodecDescriptor * codec_descriptor
AVCodecDescriptor.
Definition: avcodec.h:1828
rational.h
AVCodecContext::coded_side_data
AVPacketSideData * coded_side_data
Additional data associated with the entire coded stream.
Definition: avcodec.h:1919
AVSubtitleRect
Definition: avcodec.h:2245
AVSubtitle::num_rects
unsigned num_rects
Definition: avcodec.h:2277
av_parser_iterate
const AVCodecParser * av_parser_iterate(void **opaque)
Iterate over all registered codec parsers.
Definition: parsers.c:86
AVCodecContext::intra_matrix
uint16_t * intra_matrix
custom intra quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:941
AVCodecContext::mv0_threshold
int mv0_threshold
Note: Value depends upon the compare function used for fullpel ME.
Definition: avcodec.h:1012
AVCodecContext::lumi_masking
float lumi_masking
luminance masking (0-> disabled)
Definition: avcodec.h:771
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVCodecContext::color_trc
enum AVColorTransferCharacteristic color_trc
Color Transfer Characteristic.
Definition: avcodec.h:1026
AVPacketSideData
This structure stores auxiliary information for decoding, presenting, or otherwise processing the cod...
Definition: packet.h:373
AVCodecParserContext::pts_dts_delta
int pts_dts_delta
Presentation delay of current frame in units of AVCodecContext.time_base.
Definition: avcodec.h:2871
AVCodecContext::field_order
enum AVFieldOrder field_order
Field order.
Definition: avcodec.h:1065
AVHWAccel::capabilities
int capabilities
Hardware accelerated codec capabilities.
Definition: avcodec.h:2166
version_major.h
AVCodecContext::b_quant_offset
float b_quant_offset
qscale offset between IP and B-frames
Definition: avcodec.h:740
AVCodecParserContext::height
int height
Definition: avcodec.h:2921
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:351
RcOverride::qscale
int qscale
Definition: avcodec.h:207
AVCodecContext::subtitle_header
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:1780
AVSubtitleRect::linesize
int linesize[4]
Definition: avcodec.h:2257
AVCodecParserContext::cur_frame_start_index
int cur_frame_start_index
Definition: avcodec.h:2809
AVCodecContext::me_pre_cmp
int me_pre_cmp
motion estimation prepass comparison function
Definition: avcodec.h:889
AVDictionary
Definition: dict.c:34
AVColorPrimaries
AVColorPrimaries
Chromaticity coordinates of the source primaries.
Definition: pixfmt.h:559
avcodec_default_get_format
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: decode.c:1045
AVCodecContext::slice_offset
attribute_deprecated int * slice_offset
slice offsets in the frame in bytes
Definition: avcodec.h:816
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:929
avcodec_is_open
int avcodec_is_open(AVCodecContext *s)
Definition: avcodec.c:710
AVCodecContext::qmax
int qmax
maximum quantizer
Definition: avcodec.h:1259
AVCodecParserContext::coded_width
int coded_width
Dimensions of the coded video.
Definition: avcodec.h:2926
AVCodecContext::delay
int delay
Codec delay.
Definition: avcodec.h:608
AVCodecContext::me_subpel_quality
int me_subpel_quality
subpel ME quality
Definition: avcodec.h:903
AVCodecContext::mb_cmp
int mb_cmp
macroblock comparison function (not supported yet)
Definition: avcodec.h:845
AVPictureStructure
AVPictureStructure
Definition: avcodec.h:2774
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:308
SUBTITLE_ASS
@ SUBTITLE_ASS
Formatted text, the ass field must be set by the decoder and is authoritative.
Definition: avcodec.h:2240
AVCodecContext::slice_count
attribute_deprecated int slice_count
slice count
Definition: avcodec.h:808
AVCodecParserContext::parser
const struct AVCodecParser * parser
Definition: avcodec.h:2783
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:1807
AVCodecContext::skip_top
int skip_top
Number of macroblock rows at the top which are skipped.
Definition: avcodec.h:964
AVCodecParserContext::offset
int64_t offset
byte offset from starting packet start
Definition: avcodec.h:2821
AVHWAccel
Definition: avcodec.h:2133
AVCodecParserContext::key_frame
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:2830
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:371
AVCodecContext::skip_idct
enum AVDiscard skip_idct
Skip IDCT/dequantization for selected frames.
Definition: avcodec.h:1763
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:757
AVCodecContext::nsse_weight
int nsse_weight
noise vs.
Definition: avcodec.h:1592
AVCodecContext::codec
const struct AVCodec * codec
Definition: avcodec.h:454
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:2111
AVCodecContext::skip_frame
enum AVDiscard skip_frame
Skip decoding for selected frames.
Definition: avcodec.h:1770
AVCodecContext::thread_count
int thread_count
thread count is used to decide how many independent tasks should be passed to execute()
Definition: avcodec.h:1536
samplefmt.h
AVSubtitleRect::x
int x
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2246
AVCodecContext::initial_padding
int initial_padding
Audio only.
Definition: avcodec.h:1798
AVCodecContext::refs
int refs
number of reference frames
Definition: avcodec.h:1005
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:525
AVCodecContext::bit_rate_tolerance
int bit_rate_tolerance
number of bits the bitstream is allowed to diverge from the reference.
Definition: avcodec.h:503
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:1477
av_parser_init
AVCodecParserContext * av_parser_init(int codec_id)
Definition: parser.c:32
pts
static int64_t pts
Definition: transcode_aac.c:643
AVCodecContext::coded_height
int coded_height
Definition: avcodec.h:640
AVCodecContext::max_samples
int64_t max_samples
The number of samples per frame to maximally accept.
Definition: avcodec.h:2051
codec.h
AVCodecParserContext::dts
int64_t dts
Definition: avcodec.h:2801
AVSubtitleRect::ass
char * ass
0 terminated ASS/SSA compatible event line.
Definition: avcodec.h:2268
avsubtitle_free
void avsubtitle_free(AVSubtitle *sub)
Free all allocated data in the given subtitle struct.
Definition: avcodec.c:413
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:1241
avcodec_decode_subtitle2
int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub, int *got_sub_ptr, const AVPacket *avpkt)
Decode a subtitle message.
Definition: decode.c:969
AV_PICTURE_STRUCTURE_FRAME
@ AV_PICTURE_STRUCTURE_FRAME
coded as frame
Definition: avcodec.h:2778
RcOverride::quality_factor
float quality_factor
Definition: avcodec.h:208
AVCodecContext::color_primaries
enum AVColorPrimaries color_primaries
Chromaticity coordinates of the source primaries.
Definition: avcodec.h:1019
AVCodecParserContext::cur_frame_end
int64_t cur_frame_end[AV_PARSER_PTS_NB]
Definition: avcodec.h:2822
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:1835
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:1316
codec_id.h
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:547
AVCodecContext::has_b_frames
int has_b_frames
Size of the frame reordering buffer in the decoder.
Definition: avcodec.h:748
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:154
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:198
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:1338
AVCodecContext::global_quality
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:511
AVCodecParserContext::fetch_timestamp
int fetch_timestamp
Definition: avcodec.h:2806
RcOverride
Definition: avcodec.h:204
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demux_decode.c:41
AVCodecParserContext::last_pts
int64_t last_pts
Definition: avcodec.h:2804
AVSubtitleRect::y
int y
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2247
AVCodecContext::error_concealment
int error_concealment
error concealment flags
Definition: avcodec.h:1382
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:715
AVSubtitleType
AVSubtitleType
Definition: avcodec.h:2225
avcodec_close
attribute_deprecated 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:503
AVCodecContext::thread_type
int thread_type
Which multithreading methods to use.
Definition: avcodec.h:1546
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1521
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:377
RcOverride::start_frame
int start_frame
Definition: avcodec.h:205
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:2937
AVSubtitle::pts
int64_t pts
Same as packet pts, in AV_TIME_BASE.
Definition: avcodec.h:2279
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:144
AVCodecContext::max_pixels
int64_t max_pixels
The number of pixels per image to maximally accept.
Definition: avcodec.h:1963
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:389
AVCodecContext::rc_max_rate
int64_t rc_max_rate
maximum bitrate
Definition: avcodec.h:1288
AVCodecContext::error
uint64_t error[AV_NUM_DATA_POINTERS]
error
Definition: avcodec.h:1470
AVSubtitleRect::text
char * text
0 terminated plain UTF-8 text
Definition: avcodec.h:2261
frame
static AVFrame * frame
Definition: demux_decode.c:54
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:455
AVCodecContext::p_masking
float p_masking
p block masking (0-> disabled)
Definition: avcodec.h:792
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:2857
AVCodecParserContext::repeat_pict
int repeat_pict
This field is used for proper frame duration computation in lavf.
Definition: avcodec.h:2799
AV_PICTURE_STRUCTURE_BOTTOM_FIELD
@ AV_PICTURE_STRUCTURE_BOTTOM_FIELD
coded as bottom field
Definition: avcodec.h:2777
AVCodecContext::rc_buffer_size
int rc_buffer_size
decoder bitstream buffer size
Definition: avcodec.h:1273
AVCodecContext::sub_charenc
char * sub_charenc
DTS of the last frame.
Definition: avcodec.h:1845
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const struct AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
AVSubtitleRect::w
int w
width of pict, undefined when pict is not set
Definition: avcodec.h:2248
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:188
AVCodecContext::apply_cropping
int apply_cropping
Video decoding only.
Definition: avcodec.h:2021
AVCodecContext::color_range
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:1043
AVCodecContext::slice_flags
int slice_flags
slice flags
Definition: avcodec.h:919
AVCodecParser::parser_close
void(* parser_close)(AVCodecParserContext *s)
Definition: avcodec.h:2950
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:169
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:1920
AVCodecContext::qblur
float qblur
amount of qscale smoothing over time (0.0-1.0)
Definition: avcodec.h:1245
AV_PICTURE_STRUCTURE_TOP_FIELD
@ AV_PICTURE_STRUCTURE_TOP_FIELD
coded as top field
Definition: avcodec.h:2776
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:495
AVCodecParser::split
int(* split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
Definition: avcodec.h:2951
AVCodecContext::subtitle_header_size
int subtitle_header_size
Definition: avcodec.h:1781
AVSubtitleRect::data
uint8_t * data[4]
data+linesize for the bitmap of this subtitle.
Definition: avcodec.h:2256
AVCodecContext::trailing_padding
int trailing_padding
Audio only.
Definition: avcodec.h:1955
AVCodecContext::ildct_cmp
int ildct_cmp
interlaced DCT comparison function
Definition: avcodec.h:851
avcodec_license
const char * avcodec_license(void)
Return the libavcodec license.
Definition: version.c:46
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:1309
avcodec_open2
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:128
AVCodecParserContext::flags
int flags
Definition: avcodec.h:2814
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:833
AVCodecParserContext::picture_structure
enum AVPictureStructure picture_structure
Indicate whether a picture is coded as a frame, top field or bottom field.
Definition: avcodec.h:2907
AVCodecContext::trellis
int trellis
trellis RD quantization
Definition: avcodec.h:1323
AVCodecContext::level
int level
Encoding level descriptor.
Definition: avcodec.h:1744
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:222
avcodec_get_subtitle_rect_class
const AVClass * avcodec_get_subtitle_rect_class(void)
Get the AVClass for AVSubtitleRect.
Definition: options.c:213
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:778
AVCodecContext::qcompress
float qcompress
amount of qscale change between easy & hard scenes (0.0-1.0)
Definition: avcodec.h:1244
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:567
AVCodecContext::lowres
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:1528
options
const OptionDef options[]
AVCodecContext::stats_out
char * stats_out
pass1 encoding statistics output buffer
Definition: avcodec.h:1330
AVCodecContext::rc_override
RcOverride * rc_override
Definition: avcodec.h:1281
AVCodecContext::flags2
int flags2
AV_CODEC_FLAG2_*.
Definition: avcodec.h:532
AVMediaType
AVMediaType
Definition: avutil.h:199
AVCodecParserContext::frame_offset
int64_t frame_offset
Definition: avcodec.h:2784
AVCodecContext::gop_size
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:647
AVCodecParser::codec_ids
int codec_ids[7]
Definition: avcodec.h:2941
AVCodecContext::extra_hw_frames
int extra_hw_frames
Definition: avcodec.h:2035
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:313
AVCodecParserContext::next_frame_offset
int64_t next_frame_offset
Definition: avcodec.h:2787
AVCodecParserContext::cur_frame_offset
int64_t cur_frame_offset[AV_PARSER_PTS_NB]
Definition: avcodec.h:2810
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1084
AVCodecContext::pkt_timebase
AVRational pkt_timebase
Timebase in which pkt_dts/pts and AVPacket.dts/pts are expressed.
Definition: avcodec.h:1821
size
int size
Definition: twinvq_data.h:10344
AVCodecParserContext::width
int width
Dimensions of the decoded video intended for presentation.
Definition: avcodec.h:2920
AV_NUM_DATA_POINTERS
#define AV_NUM_DATA_POINTERS
Definition: frame.h:341
AVCodecContext::me_range
int me_range
maximum motion estimation search range in subpel units If 0 then no limit.
Definition: avcodec.h:912
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:2946
AVCodecContext::skip_alpha
int skip_alpha
Skip processing alpha if supported by codec.
Definition: avcodec.h:1871
AVCodecContext::chroma_intra_matrix
uint16_t * chroma_intra_matrix
custom intra quantization matrix
Definition: avcodec.h:1885
AVCodecContext::skip_bottom
int skip_bottom
Number of macroblock rows at the bottom which are skipped.
Definition: avcodec.h:971
AVCodecContext::last_predictor_count
int last_predictor_count
amount of previous MV predictors (2a+1 x 2a+1 square)
Definition: avcodec.h:882
AVSubtitle::end_display_time
uint32_t end_display_time
Definition: avcodec.h:2276
frame.h
AVSubtitleRect::type
enum AVSubtitleType type
Definition: avcodec.h:2259
SUBTITLE_TEXT
@ SUBTITLE_TEXT
Plain text, the text field must be set by the decoder and is authoritative.
Definition: avcodec.h:2234
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:2226
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:839
AVCodecContext::pts_correction_num_faulty_dts
int64_t pts_correction_num_faulty_dts
Number of incorrect PTS values so far.
Definition: avcodec.h:1836
height
#define height
AVCodecContext::pts_correction_last_pts
int64_t pts_correction_last_pts
Number of incorrect DTS values so far.
Definition: avcodec.h:1837
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:57
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:1159
attributes.h
AVCodecInternal
Definition: internal.h:49
AVCodecContext::skip_loop_filter
enum AVDiscard skip_loop_filter
Skip loop filtering for selected frames.
Definition: avcodec.h:1756
SUBTITLE_BITMAP
@ SUBTITLE_BITMAP
A bitmap, pict will be set.
Definition: avcodec.h:2228
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:733
AVCodecParserContext::cur_frame_pts
int64_t cur_frame_pts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2811
AVChromaLocation
AVChromaLocation
Location of chroma samples.
Definition: pixfmt.h:706
AVCodecParserContext::cur_frame_pos
int64_t cur_frame_pos[AV_PARSER_PTS_NB]
Position of the packet in file.
Definition: avcodec.h:2878
AVHWAccel::name
const char * name
Name of the hardware accelerated codec.
Definition: avcodec.h:2139
AVSubtitleRect::flags
int flags
Definition: avcodec.h:2270
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1514
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:260
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:709
AVCodecParserContext::pos
int64_t pos
Byte position of currently parsed frame in stream.
Definition: avcodec.h:2883
AVSubtitle::format
uint16_t format
Definition: avcodec.h:2274
log.h
RcOverride::end_frame
int end_frame
Definition: avcodec.h:206
AVCodecContext::properties
unsigned properties
Properties of the stream that gets decoded.
Definition: avcodec.h:1908
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:546
AVSubtitleRect::nb_colors
int nb_colors
number of colors in pict, undefined when pict is not set
Definition: avcodec.h:2250
packet.h
AVCodecContext::intra_dc_precision
int intra_dc_precision
precision of the intra DC coefficient - 8
Definition: avcodec.h:957
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:613
AVCodecContext::cutoff
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1124
AVCodecContext::hwaccel_flags
int hwaccel_flags
Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated decoding (if active).
Definition: avcodec.h:1994
AVCodecParserContext::cur_offset
int64_t cur_offset
Definition: avcodec.h:2785
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:52
AVCodecParser::parser_init
int(* parser_init)(AVCodecParserContext *s)
Definition: avcodec.h:2943
AVCodecContext::pts_correction_last_dts
int64_t pts_correction_last_dts
PTS of the last frame.
Definition: avcodec.h:1838
AVCodecContext::dia_size
int dia_size
ME diamond size & shape.
Definition: avcodec.h:875
AVCodecContext::dump_separator
uint8_t * dump_separator
dump format separator.
Definition: avcodec.h:1893
AVCodecContext::mb_lmin
int mb_lmin
minimum MB Lagrange multiplier
Definition: avcodec.h:978
av_get_audio_frame_duration
int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
Return audio frame duration.
Definition: utils.c:794
AVCodecContext::idct_algo
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:1490
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:1985
AVCodecContext::chroma_sample_location
enum AVChromaLocation chroma_sample_location
This defines the location of chroma samples.
Definition: avcodec.h:1050
AVCodecContext::height
int height
Definition: avcodec.h:625
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:518
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:662
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:1944
AVCodecParserContext
Definition: avcodec.h:2781
AVCodecContext::sub_charenc_mode
int sub_charenc_mode
Subtitles character encoding mode.
Definition: avcodec.h:1853
AVCodecContext::frame_num
int64_t frame_num
Frame counter, set by libavcodec.
Definition: avcodec.h:2122
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:1159
ret
ret
Definition: filter_design.txt:187
AVSubtitleRect::h
int h
height of pict, undefined when pict is not set
Definition: avcodec.h:2249
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:1117
pixfmt.h
avcodec_flush_buffers
void avcodec_flush_buffers(AVCodecContext *avctx)
Reset the internal codec state / flush internal buffers.
Definition: avcodec.c:384
AVCodecParserContext::coded_height
int coded_height
Definition: avcodec.h:2927
AVCodecContext::strict_std_compliance
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1375
AVCodecContext::opaque
void * opaque
Private data of the user, can be used to carry app specific stuff.
Definition: avcodec.h:487
pos
unsigned int pos
Definition: spdifenc.c:413
AVCodecParser::priv_data_size
int priv_data_size
Definition: avcodec.h:2942
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:687
AVCodecContext::max_qdiff
int max_qdiff
maximum quantizer difference between frames
Definition: avcodec.h:1266
AVCodecContext::dark_masking
float dark_masking
darkness masking (0-> disabled)
Definition: avcodec.h:799
AVCodecContext
main external API structure.
Definition: avcodec.h:445
AVCodecContext::active_thread_type
int active_thread_type
Which multithreading methods are in use by the codec.
Definition: avcodec.h:1555
c2
static const uint64_t c2
Definition: murmur3.c:53
AVCodecParserContext::field_order
enum AVFieldOrder field_order
Definition: avcodec.h:2897
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:1566
channel_layout.h
AVCodecContext::qmin
int qmin
minimum quantizer
Definition: avcodec.h:1252
AVCodecContext::bidir_refine
int bidir_refine
Definition: avcodec.h:991
AVCodecContext::profile
int profile
profile
Definition: avcodec.h:1600
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:65
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:2103
AVCodecContext::spatial_cplx_masking
float spatial_cplx_masking
spatial complexity masking (0-> disabled)
Definition: avcodec.h:785
AVCodecContext::i_quant_offset
float i_quant_offset
qscale offset between P and I-frames
Definition: avcodec.h:764
AVCodecContext::discard_damaged_percentage
int discard_damaged_percentage
The percentage of damaged samples to discard a frame.
Definition: avcodec.h:2043
AVCodecContext::ticks_per_frame
attribute_deprecated int ticks_per_frame
For some codecs, the time base is closer to the field rate than the frame rate.
Definition: avcodec.h:583
AVCodecContext::mb_lmax
int mb_lmax
maximum MB Lagrange multiplier
Definition: avcodec.h:985
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:2061
AVCodecContext::pre_dia_size
int pre_dia_size
ME prepass diamond size & shape.
Definition: avcodec.h:896
AVCodecContext::debug
int debug
debug
Definition: avcodec.h:1392
AVCodecContext::coded_width
int coded_width
Bitstream width / height, may be different from width/height e.g.
Definition: avcodec.h:640
AVCodecContext::codec_type
enum AVMediaType codec_type
Definition: avcodec.h:453
AVCodecContext::seek_preroll
int seek_preroll
Number of samples to skip after a discontinuity.
Definition: avcodec.h:1878
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:724
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
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:1302
avcodec_parameters_from_context
int avcodec_parameters_from_context(struct AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: codec_par.c:137
AVCodecContext::codec_tag
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:470
codec_par.h
AV_PARSER_PTS_NB
#define AV_PARSER_PTS_NB
Definition: avcodec.h:2808
AVCodecContext::slices
int slices
Number of slices.
Definition: avcodec.h:1059
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
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:83
AVCodecParserContext::last_pos
int64_t last_pos
Previous frame byte position.
Definition: avcodec.h:2888
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:950
AVCodecParser
Definition: avcodec.h:2940
AVCodecContext::rc_override_count
int rc_override_count
ratecontrol override, see RcOverride
Definition: avcodec.h:1280
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:625
AVCodecContext::frame_number
attribute_deprecated int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:1110
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
AVCodecParserContext::priv_data
void * priv_data
Definition: avcodec.h:2782
AVCodecContext::sw_pix_fmt
enum AVPixelFormat sw_pix_fmt
Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1814
AVCodecParserContext::cur_frame_dts
int64_t cur_frame_dts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2812
AVCodecContext::codec_whitelist
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avcodec.h:1901
AVDiscard
AVDiscard
Definition: defs.h:210
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:652
AVCodecParserContext::last_dts
int64_t last_dts
Definition: avcodec.h:2805
codec_desc.h
int
int
Definition: ffmpeg_filter.c:424
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:1585
AVHWAccel::pix_fmt
enum AVPixelFormat pix_fmt
Supported pixel format.
Definition: avcodec.h:2160
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:826
AVSubtitle::start_display_time
uint32_t start_display_time
Definition: avcodec.h:2275
AVCodecContext::compression_level
int compression_level
Definition: avcodec.h:517
av_parser_close
void av_parser_close(AVCodecParserContext *s)
Definition: parser.c:193
AVHWAccel::id
enum AVCodecID id
Codec implemented by the hardware accelerator.
Definition: avcodec.h:2153