FFmpeg
avcodec.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
23 
24 /**
25  * @file
26  * @ingroup libavc
27  * Libavcodec external API header
28  */
29 
30 #include "libavutil/samplefmt.h"
31 #include "libavutil/attributes.h"
32 #include "libavutil/avutil.h"
33 #include "libavutil/buffer.h"
34 #include "libavutil/dict.h"
35 #include "libavutil/frame.h"
36 #include "libavutil/log.h"
37 #include "libavutil/pixfmt.h"
38 #include "libavutil/rational.h"
39 
40 #include "codec.h"
41 #include "codec_desc.h"
42 #include "codec_par.h"
43 #include "codec_id.h"
44 #include "defs.h"
45 #include "packet.h"
46 #include "version_major.h"
47 #ifndef HAVE_AV_CONFIG_H
48 /* When included as part of the ffmpeg build, only include the major version
49  * to avoid unnecessary rebuilds. When included externally, keep including
50  * the full version information. */
51 #include "version.h"
52 #endif
53 
54 /**
55  * @defgroup libavc libavcodec
56  * Encoding/Decoding Library
57  *
58  * @{
59  *
60  * @defgroup lavc_decoding Decoding
61  * @{
62  * @}
63  *
64  * @defgroup lavc_encoding Encoding
65  * @{
66  * @}
67  *
68  * @defgroup lavc_codec Codecs
69  * @{
70  * @defgroup lavc_codec_native Native Codecs
71  * @{
72  * @}
73  * @defgroup lavc_codec_wrappers External library wrappers
74  * @{
75  * @}
76  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
77  * @{
78  * @}
79  * @}
80  * @defgroup lavc_internal Internal
81  * @{
82  * @}
83  * @}
84  */
85 
86 /**
87  * @ingroup libavc
88  * @defgroup lavc_encdec send/receive encoding and decoding API overview
89  * @{
90  *
91  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
92  * avcodec_receive_packet() functions provide an encode/decode API, which
93  * decouples input and output.
94  *
95  * The API is very similar for encoding/decoding and audio/video, and works as
96  * follows:
97  * - Set up and open the AVCodecContext as usual.
98  * - Send valid input:
99  * - For decoding, call avcodec_send_packet() to give the decoder raw
100  * compressed data in an AVPacket.
101  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
102  * containing uncompressed audio or video.
103  *
104  * In both cases, it is recommended that AVPackets and AVFrames are
105  * refcounted, or libavcodec might have to copy the input data. (libavformat
106  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
107  * refcounted AVFrames.)
108  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
109  * functions and process their output:
110  * - For decoding, call avcodec_receive_frame(). On success, it will return
111  * an AVFrame containing uncompressed audio or video data.
112  * - For encoding, call avcodec_receive_packet(). On success, it will return
113  * an AVPacket with a compressed frame.
114  *
115  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
116  * AVERROR(EAGAIN) return value means that new input data is required to
117  * return new output. In this case, continue with sending input. For each
118  * input frame/packet, the codec will typically return 1 output frame/packet,
119  * but it can also be 0 or more than 1.
120  *
121  * At the beginning of decoding or encoding, the codec might accept multiple
122  * input frames/packets without returning a frame, until its internal buffers
123  * are filled. This situation is handled transparently if you follow the steps
124  * outlined above.
125  *
126  * In theory, sending input can result in EAGAIN - this should happen only if
127  * not all output was received. You can use this to structure alternative decode
128  * or encode loops other than the one suggested above. For example, you could
129  * try sending new input on each iteration, and try to receive output if that
130  * returns EAGAIN.
131  *
132  * End of stream situations. These require "flushing" (aka draining) the codec,
133  * as the codec might buffer multiple frames or packets internally for
134  * performance or out of necessity (consider B-frames).
135  * This is handled as follows:
136  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
137  * or avcodec_send_frame() (encoding) functions. This will enter draining
138  * mode.
139  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
140  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
141  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
142  * - Before decoding can be resumed again, the codec has to be reset with
143  * avcodec_flush_buffers().
144  *
145  * Using the API as outlined above is highly recommended. But it is also
146  * possible to call functions outside of this rigid schema. For example, you can
147  * call avcodec_send_packet() repeatedly without calling
148  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
149  * until the codec's internal buffer has been filled up (which is typically of
150  * size 1 per output frame, after initial input), and then reject input with
151  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
152  * read at least some output.
153  *
154  * Not all codecs will follow a rigid and predictable dataflow; the only
155  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
156  * one end implies that a receive/send call on the other end will succeed, or
157  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
158  * permit unlimited buffering of input or output.
159  *
160  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
161  * would be an invalid state, which could put the codec user into an endless
162  * loop. The API has no concept of time either: it cannot happen that trying to
163  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
164  * later accepts the packet (with no other receive/flush API calls involved).
165  * The API is a strict state machine, and the passage of time is not supposed
166  * to influence it. Some timing-dependent behavior might still be deemed
167  * acceptable in certain cases. But it must never result in both send/receive
168  * returning EAGAIN at the same time at any point. It must also absolutely be
169  * avoided that the current state is "unstable" and can "flip-flop" between
170  * the send/receive APIs allowing progress. For example, it's not allowed that
171  * the codec randomly decides that it actually wants to consume a packet now
172  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
173  * avcodec_send_packet() call.
174  * @}
175  */
176 
177 /**
178  * @defgroup lavc_core Core functions/structures.
179  * @ingroup libavc
180  *
181  * Basic definitions, functions for querying libavcodec capabilities,
182  * allocating core structures, etc.
183  * @{
184  */
185 
186 /**
187  * @ingroup lavc_encoding
188  * minimum encoding buffer size
189  * Used to avoid some checks during header writing.
190  */
191 #define AV_INPUT_BUFFER_MIN_SIZE 16384
192 
193 /**
194  * @ingroup lavc_encoding
195  */
196 typedef struct RcOverride{
199  int qscale; // If this is 0 then quality_factor will be used instead.
201 } RcOverride;
202 
203 /* encoding support
204  These flags can be passed in AVCodecContext.flags before initialization.
205  Note: Not everything is supported yet.
206 */
207 
208 /**
209  * Allow decoders to produce frames with data planes that are not aligned
210  * to CPU requirements (e.g. due to cropping).
211  */
212 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
213 /**
214  * Use fixed qscale.
215  */
216 #define AV_CODEC_FLAG_QSCALE (1 << 1)
217 /**
218  * 4 MV per MB allowed / advanced prediction for H.263.
219  */
220 #define AV_CODEC_FLAG_4MV (1 << 2)
221 /**
222  * Output even those frames that might be corrupted.
223  */
224 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
225 /**
226  * Use qpel MC.
227  */
228 #define AV_CODEC_FLAG_QPEL (1 << 4)
229 /**
230  * Don't output frames whose parameters differ from first
231  * decoded frame in stream.
232  */
233 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
234 /**
235  * Request the encoder to output reconstructed frames, i.e. frames that would be
236  * produced by decoding the encoded bistream. These frames may be retrieved by
237  * calling avcodec_receive_frame() immediately after a successful call to
238  * avcodec_receive_packet().
239  *
240  * Should only be used with encoders flagged with the
241  * AV_CODEC_CAP_ENCODER_RECON_FRAME capability.
242  */
243 #define AV_CODEC_FLAG_RECON_FRAME (1 << 6)
244 /**
245  * Use internal 2pass ratecontrol in first pass mode.
246  */
247 #define AV_CODEC_FLAG_PASS1 (1 << 9)
248 /**
249  * Use internal 2pass ratecontrol in second pass mode.
250  */
251 #define AV_CODEC_FLAG_PASS2 (1 << 10)
252 /**
253  * loop filter.
254  */
255 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
256 /**
257  * Only decode/encode grayscale.
258  */
259 #define AV_CODEC_FLAG_GRAY (1 << 13)
260 /**
261  * error[?] variables will be set during encoding.
262  */
263 #define AV_CODEC_FLAG_PSNR (1 << 15)
264 #if FF_API_FLAG_TRUNCATED
265 /**
266  * Input bitstream might be truncated at a random location
267  * instead of only at frame boundaries.
268  *
269  * @deprecated use codec parsers for packetizing input
270  */
271 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
272 #endif
273 /**
274  * Use interlaced DCT.
275  */
276 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
277 /**
278  * Force low delay.
279  */
280 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
281 /**
282  * Place global headers in extradata instead of every keyframe.
283  */
284 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
285 /**
286  * Use only bitexact stuff (except (I)DCT).
287  */
288 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
289 /* Fx : Flag for H.263+ extra options */
290 /**
291  * H.263 advanced intra coding / MPEG-4 AC prediction
292  */
293 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
294 /**
295  * interlaced motion estimation
296  */
297 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
298 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
299 
300 /**
301  * Allow non spec compliant speedup tricks.
302  */
303 #define AV_CODEC_FLAG2_FAST (1 << 0)
304 /**
305  * Skip bitstream encoding.
306  */
307 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
308 /**
309  * Place global headers at every keyframe instead of in extradata.
310  */
311 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
312 
313 /**
314  * timecode is in drop frame format. DEPRECATED!!!!
315  */
316 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
317 
318 /**
319  * Input bitstream might be truncated at a packet boundaries
320  * instead of only at frame boundaries.
321  */
322 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
323 /**
324  * Discard cropping information from SPS.
325  */
326 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
327 
328 /**
329  * Show all frames before the first keyframe
330  */
331 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
332 /**
333  * Export motion vectors through frame side data
334  */
335 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
336 /**
337  * Do not skip samples and export skip information as frame side data
338  */
339 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
340 /**
341  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
342  */
343 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
344 /**
345  * Generate/parse ICC profiles on encode/decode, as appropriate for the type of
346  * file. No effect on codecs which cannot contain embedded ICC profiles, or
347  * when compiled without support for lcms2.
348  */
349 #define AV_CODEC_FLAG2_ICC_PROFILES (1U << 31)
350 
351 /* Exported side data.
352  These flags can be passed in AVCodecContext.export_side_data before initialization.
353 */
354 /**
355  * Export motion vectors through frame side data
356  */
357 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
358 /**
359  * Export encoder Producer Reference Time through packet side data
360  */
361 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
362 /**
363  * Decoding only.
364  * Export the AVVideoEncParams structure through frame side data.
365  */
366 #define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
367 /**
368  * Decoding only.
369  * Do not apply film grain, export it instead.
370  */
371 #define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
372 
373 /**
374  * The decoder will keep a reference to the frame and may reuse it later.
375  */
376 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
377 
378 /**
379  * The encoder will keep a reference to the packet and may reuse it later.
380  */
381 #define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
382 
383 struct AVCodecInternal;
384 
385 /**
386  * main external API structure.
387  * New fields can be added to the end with minor version bumps.
388  * Removal, reordering and changes to existing fields require a major
389  * version bump.
390  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
391  * applications.
392  * The name string for AVOptions options matches the associated command line
393  * parameter name and can be found in libavcodec/options_table.h
394  * The AVOption/command line parameter names differ in some cases from the C
395  * structure field names for historic reasons or brevity.
396  * sizeof(AVCodecContext) must not be used outside libav*.
397  */
398 typedef struct AVCodecContext {
399  /**
400  * information on struct for av_log
401  * - set by avcodec_alloc_context3
402  */
405 
406  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
407  const struct AVCodec *codec;
408  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
409 
410  /**
411  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
412  * This is used to work around some encoder bugs.
413  * A demuxer should set this to what is stored in the field used to identify the codec.
414  * If there are multiple such fields in a container then the demuxer should choose the one
415  * which maximizes the information about the used codec.
416  * If the codec tag field in a container is larger than 32 bits then the demuxer should
417  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
418  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
419  * first.
420  * - encoding: Set by user, if not then the default based on codec_id will be used.
421  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
422  */
423  unsigned int codec_tag;
424 
425  void *priv_data;
426 
427  /**
428  * Private context used for internal data.
429  *
430  * Unlike priv_data, this is not codec-specific. It is used in general
431  * libavcodec functions.
432  */
433  struct AVCodecInternal *internal;
434 
435  /**
436  * Private data of the user, can be used to carry app specific stuff.
437  * - encoding: Set by user.
438  * - decoding: Set by user.
439  */
440  void *opaque;
441 
442  /**
443  * the average bitrate
444  * - encoding: Set by user; unused for constant quantizer encoding.
445  * - decoding: Set by user, may be overwritten by libavcodec
446  * if this info is available in the stream
447  */
448  int64_t bit_rate;
449 
450  /**
451  * number of bits the bitstream is allowed to diverge from the reference.
452  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
453  * - encoding: Set by user; unused for constant quantizer encoding.
454  * - decoding: unused
455  */
457 
458  /**
459  * Global quality for codecs which cannot change it per frame.
460  * This should be proportional to MPEG-1/2/4 qscale.
461  * - encoding: Set by user.
462  * - decoding: unused
463  */
465 
466  /**
467  * - encoding: Set by user.
468  * - decoding: unused
469  */
471 #define FF_COMPRESSION_DEFAULT -1
472 
473  /**
474  * AV_CODEC_FLAG_*.
475  * - encoding: Set by user.
476  * - decoding: Set by user.
477  */
478  int flags;
479 
480  /**
481  * AV_CODEC_FLAG2_*
482  * - encoding: Set by user.
483  * - decoding: Set by user.
484  */
485  int flags2;
486 
487  /**
488  * some codecs need / can use extradata like Huffman tables.
489  * MJPEG: Huffman tables
490  * rv10: additional flags
491  * MPEG-4: global headers (they can be in the bitstream or here)
492  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
493  * than extradata_size to avoid problems if it is read with the bitstream reader.
494  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
495  * Must be allocated with the av_malloc() family of functions.
496  * - encoding: Set/allocated/freed by libavcodec.
497  * - decoding: Set/allocated/freed by user.
498  */
499  uint8_t *extradata;
501 
502  /**
503  * This is the fundamental unit of time (in seconds) in terms
504  * of which frame timestamps are represented. For fixed-fps content,
505  * timebase should be 1/framerate and timestamp increments should be
506  * identically 1.
507  * This often, but not always is the inverse of the frame rate or field rate
508  * for video. 1/time_base is not the average frame rate if the frame rate is not
509  * constant.
510  *
511  * Like containers, elementary streams also can store timestamps, 1/time_base
512  * is the unit in which these timestamps are specified.
513  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
514  * vop_time_increment_resolution and fixed_vop_rate
515  * (fixed_vop_rate == 0 implies that it is different from the framerate)
516  *
517  * - encoding: MUST be set by user.
518  * - decoding: the use of this field for decoding is deprecated.
519  * Use framerate instead.
520  */
522 
523  /**
524  * For some codecs, the time base is closer to the field rate than the frame rate.
525  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
526  * if no telecine is used ...
527  *
528  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
529  */
531 
532  /**
533  * Codec delay.
534  *
535  * Encoding: Number of frames delay there will be from the encoder input to
536  * the decoder output. (we assume the decoder matches the spec)
537  * Decoding: Number of frames delay in addition to what a standard decoder
538  * as specified in the spec would produce.
539  *
540  * Video:
541  * Number of frames the decoded output will be delayed relative to the
542  * encoded input.
543  *
544  * Audio:
545  * For encoding, this field is unused (see initial_padding).
546  *
547  * For decoding, this is the number of samples the decoder needs to
548  * output before the decoder's output is valid. When seeking, you should
549  * start decoding this many samples prior to your desired seek point.
550  *
551  * - encoding: Set by libavcodec.
552  * - decoding: Set by libavcodec.
553  */
554  int delay;
555 
556 
557  /* video only */
558  /**
559  * picture width / height.
560  *
561  * @note Those fields may not match the values of the last
562  * AVFrame output by avcodec_receive_frame() due frame
563  * reordering.
564  *
565  * - encoding: MUST be set by user.
566  * - decoding: May be set by the user before opening the decoder if known e.g.
567  * from the container. Some decoders will require the dimensions
568  * to be set by the caller. During decoding, the decoder may
569  * overwrite those values as required while parsing the data.
570  */
571  int width, height;
572 
573  /**
574  * Bitstream width / height, may be different from width/height e.g. when
575  * the decoded frame is cropped before being output or lowres is enabled.
576  *
577  * @note Those field may not match the value of the last
578  * AVFrame output by avcodec_receive_frame() due frame
579  * reordering.
580  *
581  * - encoding: unused
582  * - decoding: May be set by the user before opening the decoder if known
583  * e.g. from the container. During decoding, the decoder may
584  * overwrite those values as required while parsing the data.
585  */
587 
588  /**
589  * the number of pictures in a group of pictures, or 0 for intra_only
590  * - encoding: Set by user.
591  * - decoding: unused
592  */
593  int gop_size;
594 
595  /**
596  * Pixel format, see AV_PIX_FMT_xxx.
597  * May be set by the demuxer if known from headers.
598  * May be overridden by the decoder if it knows better.
599  *
600  * @note This field may not match the value of the last
601  * AVFrame output by avcodec_receive_frame() due frame
602  * reordering.
603  *
604  * - encoding: Set by user.
605  * - decoding: Set by user if known, overridden by libavcodec while
606  * parsing the data.
607  */
609 
610  /**
611  * If non NULL, 'draw_horiz_band' is called by the libavcodec
612  * decoder to draw a horizontal band. It improves cache usage. Not
613  * all codecs can do that. You must check the codec capabilities
614  * beforehand.
615  * When multithreading is used, it may be called from multiple threads
616  * at the same time; threads might draw different parts of the same AVFrame,
617  * or multiple AVFrames, and there is no guarantee that slices will be drawn
618  * in order.
619  * The function is also used by hardware acceleration APIs.
620  * It is called at least once during frame decoding to pass
621  * the data needed for hardware render.
622  * In that mode instead of pixel data, AVFrame points to
623  * a structure specific to the acceleration API. The application
624  * reads the structure and can change some fields to indicate progress
625  * or mark state.
626  * - encoding: unused
627  * - decoding: Set by user.
628  * @param height the height of the slice
629  * @param y the y position of the slice
630  * @param type 1->top field, 2->bottom field, 3->frame
631  * @param offset offset into the AVFrame.data from which the slice should be read
632  */
634  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
635  int y, int type, int height);
636 
637  /**
638  * Callback to negotiate the pixel format. Decoding only, may be set by the
639  * caller before avcodec_open2().
640  *
641  * Called by some decoders to select the pixel format that will be used for
642  * the output frames. This is mainly used to set up hardware acceleration,
643  * then the provided format list contains the corresponding hwaccel pixel
644  * formats alongside the "software" one. The software pixel format may also
645  * be retrieved from \ref sw_pix_fmt.
646  *
647  * This callback will be called when the coded frame properties (such as
648  * resolution, pixel format, etc.) change and more than one output format is
649  * supported for those new properties. If a hardware pixel format is chosen
650  * and initialization for it fails, the callback may be called again
651  * immediately.
652  *
653  * This callback may be called from different threads if the decoder is
654  * multi-threaded, but not from more than one thread simultaneously.
655  *
656  * @param fmt list of formats which may be used in the current
657  * configuration, terminated by AV_PIX_FMT_NONE.
658  * @warning Behavior is undefined if the callback returns a value other
659  * than one of the formats in fmt or AV_PIX_FMT_NONE.
660  * @return the chosen format or AV_PIX_FMT_NONE
661  */
662  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
663 
664  /**
665  * maximum number of B-frames between non-B-frames
666  * Note: The output will be delayed by max_b_frames+1 relative to the input.
667  * - encoding: Set by user.
668  * - decoding: unused
669  */
671 
672  /**
673  * qscale factor between IP and B-frames
674  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
675  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
676  * - encoding: Set by user.
677  * - decoding: unused
678  */
680 
681  /**
682  * qscale offset between IP and B-frames
683  * - encoding: Set by user.
684  * - decoding: unused
685  */
687 
688  /**
689  * Size of the frame reordering buffer in the decoder.
690  * For MPEG-2 it is 1 IPB or 0 low delay IP.
691  * - encoding: Set by libavcodec.
692  * - decoding: Set by libavcodec.
693  */
695 
696  /**
697  * qscale factor between P- and I-frames
698  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
699  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
700  * - encoding: Set by user.
701  * - decoding: unused
702  */
704 
705  /**
706  * qscale offset between P and I-frames
707  * - encoding: Set by user.
708  * - decoding: unused
709  */
711 
712  /**
713  * luminance masking (0-> disabled)
714  * - encoding: Set by user.
715  * - decoding: unused
716  */
718 
719  /**
720  * temporary complexity masking (0-> disabled)
721  * - encoding: Set by user.
722  * - decoding: unused
723  */
725 
726  /**
727  * spatial complexity masking (0-> disabled)
728  * - encoding: Set by user.
729  * - decoding: unused
730  */
732 
733  /**
734  * p block masking (0-> disabled)
735  * - encoding: Set by user.
736  * - decoding: unused
737  */
738  float p_masking;
739 
740  /**
741  * darkness masking (0-> disabled)
742  * - encoding: Set by user.
743  * - decoding: unused
744  */
746 
747  /**
748  * slice count
749  * - encoding: Set by libavcodec.
750  * - decoding: Set by user (or 0).
751  */
753 
754  /**
755  * slice offsets in the frame in bytes
756  * - encoding: Set/allocated by libavcodec.
757  * - decoding: Set/allocated by user (or NULL).
758  */
760 
761  /**
762  * sample aspect ratio (0 if unknown)
763  * That is the width of a pixel divided by the height of the pixel.
764  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
765  * - encoding: Set by user.
766  * - decoding: Set by libavcodec.
767  */
769 
770  /**
771  * motion estimation comparison function
772  * - encoding: Set by user.
773  * - decoding: unused
774  */
775  int me_cmp;
776  /**
777  * subpixel motion estimation comparison function
778  * - encoding: Set by user.
779  * - decoding: unused
780  */
782  /**
783  * macroblock comparison function (not supported yet)
784  * - encoding: Set by user.
785  * - decoding: unused
786  */
787  int mb_cmp;
788  /**
789  * interlaced DCT comparison function
790  * - encoding: Set by user.
791  * - decoding: unused
792  */
794 #define FF_CMP_SAD 0
795 #define FF_CMP_SSE 1
796 #define FF_CMP_SATD 2
797 #define FF_CMP_DCT 3
798 #define FF_CMP_PSNR 4
799 #define FF_CMP_BIT 5
800 #define FF_CMP_RD 6
801 #define FF_CMP_ZERO 7
802 #define FF_CMP_VSAD 8
803 #define FF_CMP_VSSE 9
804 #define FF_CMP_NSSE 10
805 #define FF_CMP_W53 11
806 #define FF_CMP_W97 12
807 #define FF_CMP_DCTMAX 13
808 #define FF_CMP_DCT264 14
809 #define FF_CMP_MEDIAN_SAD 15
810 #define FF_CMP_CHROMA 256
811 
812  /**
813  * ME diamond size & shape
814  * - encoding: Set by user.
815  * - decoding: unused
816  */
817  int dia_size;
818 
819  /**
820  * amount of previous MV predictors (2a+1 x 2a+1 square)
821  * - encoding: Set by user.
822  * - decoding: unused
823  */
825 
826  /**
827  * motion estimation prepass comparison function
828  * - encoding: Set by user.
829  * - decoding: unused
830  */
832 
833  /**
834  * ME prepass diamond size & shape
835  * - encoding: Set by user.
836  * - decoding: unused
837  */
839 
840  /**
841  * subpel ME quality
842  * - encoding: Set by user.
843  * - decoding: unused
844  */
846 
847  /**
848  * maximum motion estimation search range in subpel units
849  * If 0 then no limit.
850  *
851  * - encoding: Set by user.
852  * - decoding: unused
853  */
854  int me_range;
855 
856  /**
857  * slice flags
858  * - encoding: unused
859  * - decoding: Set by user.
860  */
862 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
863 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
864 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
865 
866  /**
867  * macroblock decision mode
868  * - encoding: Set by user.
869  * - decoding: unused
870  */
872 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
873 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
874 #define FF_MB_DECISION_RD 2 ///< rate distortion
875 
876  /**
877  * custom intra quantization matrix
878  * Must be allocated with the av_malloc() family of functions, and will be freed in
879  * avcodec_free_context().
880  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
881  * - decoding: Set/allocated/freed by libavcodec.
882  */
883  uint16_t *intra_matrix;
884 
885  /**
886  * custom inter quantization matrix
887  * Must be allocated with the av_malloc() family of functions, and will be freed in
888  * avcodec_free_context().
889  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
890  * - decoding: Set/allocated/freed by libavcodec.
891  */
892  uint16_t *inter_matrix;
893 
894  /**
895  * precision of the intra DC coefficient - 8
896  * - encoding: Set by user.
897  * - decoding: Set by libavcodec
898  */
900 
901  /**
902  * Number of macroblock rows at the top which are skipped.
903  * - encoding: unused
904  * - decoding: Set by user.
905  */
906  int skip_top;
907 
908  /**
909  * Number of macroblock rows at the bottom which are skipped.
910  * - encoding: unused
911  * - decoding: Set by user.
912  */
914 
915  /**
916  * minimum MB Lagrange multiplier
917  * - encoding: Set by user.
918  * - decoding: unused
919  */
920  int mb_lmin;
921 
922  /**
923  * maximum MB Lagrange multiplier
924  * - encoding: Set by user.
925  * - decoding: unused
926  */
927  int mb_lmax;
928 
929  /**
930  * - encoding: Set by user.
931  * - decoding: unused
932  */
934 
935  /**
936  * minimum GOP size
937  * - encoding: Set by user.
938  * - decoding: unused
939  */
941 
942  /**
943  * number of reference frames
944  * - encoding: Set by user.
945  * - decoding: Set by lavc.
946  */
947  int refs;
948 
949  /**
950  * Note: Value depends upon the compare function used for fullpel ME.
951  * - encoding: Set by user.
952  * - decoding: unused
953  */
955 
956  /**
957  * Chromaticity coordinates of the source primaries.
958  * - encoding: Set by user
959  * - decoding: Set by libavcodec
960  */
962 
963  /**
964  * Color Transfer Characteristic.
965  * - encoding: Set by user
966  * - decoding: Set by libavcodec
967  */
969 
970  /**
971  * YUV colorspace type.
972  * - encoding: Set by user
973  * - decoding: Set by libavcodec
974  */
976 
977  /**
978  * MPEG vs JPEG YUV range.
979  * - encoding: Set by user
980  * - decoding: Set by libavcodec
981  */
983 
984  /**
985  * This defines the location of chroma samples.
986  * - encoding: Set by user
987  * - decoding: Set by libavcodec
988  */
990 
991  /**
992  * Number of slices.
993  * Indicates number of picture subdivisions. Used for parallelized
994  * decoding.
995  * - encoding: Set by user
996  * - decoding: unused
997  */
998  int slices;
999 
1000  /** Field order
1001  * - encoding: set by libavcodec
1002  * - decoding: Set by user.
1003  */
1005 
1006  /* audio only */
1007  int sample_rate; ///< samples per second
1008 
1009 #if FF_API_OLD_CHANNEL_LAYOUT
1010  /**
1011  * number of audio channels
1012  * @deprecated use ch_layout.nb_channels
1013  */
1015  int channels;
1016 #endif
1017 
1018  /**
1019  * audio sample format
1020  * - encoding: Set by user.
1021  * - decoding: Set by libavcodec.
1022  */
1023  enum AVSampleFormat sample_fmt; ///< sample format
1024 
1025  /* The following data should not be initialized. */
1026  /**
1027  * Number of samples per channel in an audio frame.
1028  *
1029  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1030  * except the last must contain exactly frame_size samples per channel.
1031  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1032  * frame size is not restricted.
1033  * - decoding: may be set by some decoders to indicate constant frame size
1034  */
1036 
1037  /**
1038  * Frame counter, set by libavcodec.
1039  *
1040  * - decoding: total number of frames returned from the decoder so far.
1041  * - encoding: total number of frames passed to the encoder so far.
1042  *
1043  * @note the counter is not incremented if encoding/decoding resulted in
1044  * an error.
1045  */
1047 
1048  /**
1049  * number of bytes per packet if constant and known or 0
1050  * Used by some WAV based audio codecs.
1051  */
1053 
1054  /**
1055  * Audio cutoff bandwidth (0 means "automatic")
1056  * - encoding: Set by user.
1057  * - decoding: unused
1058  */
1059  int cutoff;
1060 
1061 #if FF_API_OLD_CHANNEL_LAYOUT
1062  /**
1063  * Audio channel layout.
1064  * - encoding: set by user.
1065  * - decoding: set by user, may be overwritten by libavcodec.
1066  * @deprecated use ch_layout
1067  */
1069  uint64_t channel_layout;
1070 
1071  /**
1072  * Request decoder to use this channel layout if it can (0 for default)
1073  * - encoding: unused
1074  * - decoding: Set by user.
1075  * @deprecated use "downmix" codec private option
1076  */
1078  uint64_t request_channel_layout;
1079 #endif
1080 
1081  /**
1082  * Type of service that the audio stream conveys.
1083  * - encoding: Set by user.
1084  * - decoding: Set by libavcodec.
1085  */
1087 
1088  /**
1089  * desired sample format
1090  * - encoding: Not used.
1091  * - decoding: Set by user.
1092  * Decoder will decode to this format if it can.
1093  */
1095 
1096  /**
1097  * This callback is called at the beginning of each frame to get data
1098  * buffer(s) for it. There may be one contiguous buffer for all the data or
1099  * there may be a buffer per each data plane or anything in between. What
1100  * this means is, you may set however many entries in buf[] you feel necessary.
1101  * Each buffer must be reference-counted using the AVBuffer API (see description
1102  * of buf[] below).
1103  *
1104  * The following fields will be set in the frame before this callback is
1105  * called:
1106  * - format
1107  * - width, height (video only)
1108  * - sample_rate, channel_layout, nb_samples (audio only)
1109  * Their values may differ from the corresponding values in
1110  * AVCodecContext. This callback must use the frame values, not the codec
1111  * context values, to calculate the required buffer size.
1112  *
1113  * This callback must fill the following fields in the frame:
1114  * - data[]
1115  * - linesize[]
1116  * - extended_data:
1117  * * if the data is planar audio with more than 8 channels, then this
1118  * callback must allocate and fill extended_data to contain all pointers
1119  * to all data planes. data[] must hold as many pointers as it can.
1120  * extended_data must be allocated with av_malloc() and will be freed in
1121  * av_frame_unref().
1122  * * otherwise extended_data must point to data
1123  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1124  * the frame's data and extended_data pointers must be contained in these. That
1125  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1126  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1127  * and av_buffer_ref().
1128  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1129  * this callback and filled with the extra buffers if there are more
1130  * buffers than buf[] can hold. extended_buf will be freed in
1131  * av_frame_unref().
1132  *
1133  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1134  * avcodec_default_get_buffer2() instead of providing buffers allocated by
1135  * some other means.
1136  *
1137  * Each data plane must be aligned to the maximum required by the target
1138  * CPU.
1139  *
1140  * @see avcodec_default_get_buffer2()
1141  *
1142  * Video:
1143  *
1144  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1145  * (read and/or written to if it is writable) later by libavcodec.
1146  *
1147  * avcodec_align_dimensions2() should be used to find the required width and
1148  * height, as they normally need to be rounded up to the next multiple of 16.
1149  *
1150  * Some decoders do not support linesizes changing between frames.
1151  *
1152  * If frame multithreading is used, this callback may be called from a
1153  * different thread, but not from more than one at once. Does not need to be
1154  * reentrant.
1155  *
1156  * @see avcodec_align_dimensions2()
1157  *
1158  * Audio:
1159  *
1160  * Decoders request a buffer of a particular size by setting
1161  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1162  * however, utilize only part of the buffer by setting AVFrame.nb_samples
1163  * to a smaller value in the output frame.
1164  *
1165  * As a convenience, av_samples_get_buffer_size() and
1166  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1167  * functions to find the required data size and to fill data pointers and
1168  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1169  * since all planes must be the same size.
1170  *
1171  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1172  *
1173  * - encoding: unused
1174  * - decoding: Set by libavcodec, user can override.
1175  */
1177 
1178  /* - encoding parameters */
1179  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1180  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1181 
1182  /**
1183  * minimum quantizer
1184  * - encoding: Set by user.
1185  * - decoding: unused
1186  */
1187  int qmin;
1188 
1189  /**
1190  * maximum quantizer
1191  * - encoding: Set by user.
1192  * - decoding: unused
1193  */
1194  int qmax;
1195 
1196  /**
1197  * maximum quantizer difference between frames
1198  * - encoding: Set by user.
1199  * - decoding: unused
1200  */
1202 
1203  /**
1204  * decoder bitstream buffer size
1205  * - encoding: Set by user.
1206  * - decoding: unused
1207  */
1209 
1210  /**
1211  * ratecontrol override, see RcOverride
1212  * - encoding: Allocated/set/freed by user.
1213  * - decoding: unused
1214  */
1217 
1218  /**
1219  * maximum bitrate
1220  * - encoding: Set by user.
1221  * - decoding: Set by user, may be overwritten by libavcodec.
1222  */
1223  int64_t rc_max_rate;
1224 
1225  /**
1226  * minimum bitrate
1227  * - encoding: Set by user.
1228  * - decoding: unused
1229  */
1230  int64_t rc_min_rate;
1231 
1232  /**
1233  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1234  * - encoding: Set by user.
1235  * - decoding: unused.
1236  */
1238 
1239  /**
1240  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1241  * - encoding: Set by user.
1242  * - decoding: unused.
1243  */
1245 
1246  /**
1247  * Number of bits which should be loaded into the rc buffer before decoding starts.
1248  * - encoding: Set by user.
1249  * - decoding: unused
1250  */
1252 
1253  /**
1254  * trellis RD quantization
1255  * - encoding: Set by user.
1256  * - decoding: unused
1257  */
1258  int trellis;
1259 
1260  /**
1261  * pass1 encoding statistics output buffer
1262  * - encoding: Set by libavcodec.
1263  * - decoding: unused
1264  */
1265  char *stats_out;
1266 
1267  /**
1268  * pass2 encoding statistics input buffer
1269  * Concatenated stuff from stats_out of pass1 should be placed here.
1270  * - encoding: Allocated/set/freed by user.
1271  * - decoding: unused
1272  */
1273  char *stats_in;
1274 
1275  /**
1276  * Work around bugs in encoders which sometimes cannot be detected automatically.
1277  * - encoding: Set by user
1278  * - decoding: Set by user
1279  */
1281 #define FF_BUG_AUTODETECT 1 ///< autodetection
1282 #define FF_BUG_XVID_ILACE 4
1283 #define FF_BUG_UMP4 8
1284 #define FF_BUG_NO_PADDING 16
1285 #define FF_BUG_AMV 32
1286 #define FF_BUG_QPEL_CHROMA 64
1287 #define FF_BUG_STD_QPEL 128
1288 #define FF_BUG_QPEL_CHROMA2 256
1289 #define FF_BUG_DIRECT_BLOCKSIZE 512
1290 #define FF_BUG_EDGE 1024
1291 #define FF_BUG_HPEL_CHROMA 2048
1292 #define FF_BUG_DC_CLIP 4096
1293 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1294 #define FF_BUG_TRUNCATED 16384
1295 #define FF_BUG_IEDGE 32768
1296 
1297  /**
1298  * strictly follow the standard (MPEG-4, ...).
1299  * - encoding: Set by user.
1300  * - decoding: Set by user.
1301  * Setting this to STRICT or higher means the encoder and decoder will
1302  * generally do stupid things, whereas setting it to unofficial or lower
1303  * will mean the encoder might produce output that is not supported by all
1304  * spec-compliant decoders. Decoders don't differentiate between normal,
1305  * unofficial and experimental (that is, they always try to decode things
1306  * when they can) unless they are explicitly asked to behave stupidly
1307  * (=strictly conform to the specs)
1308  * This may only be set to one of the FF_COMPLIANCE_* values in defs.h.
1309  */
1311 
1312  /**
1313  * error concealment flags
1314  * - encoding: unused
1315  * - decoding: Set by user.
1316  */
1318 #define FF_EC_GUESS_MVS 1
1319 #define FF_EC_DEBLOCK 2
1320 #define FF_EC_FAVOR_INTER 256
1321 
1322  /**
1323  * debug
1324  * - encoding: Set by user.
1325  * - decoding: Set by user.
1326  */
1327  int debug;
1328 #define FF_DEBUG_PICT_INFO 1
1329 #define FF_DEBUG_RC 2
1330 #define FF_DEBUG_BITSTREAM 4
1331 #define FF_DEBUG_MB_TYPE 8
1332 #define FF_DEBUG_QP 16
1333 #define FF_DEBUG_DCT_COEFF 0x00000040
1334 #define FF_DEBUG_SKIP 0x00000080
1335 #define FF_DEBUG_STARTCODE 0x00000100
1336 #define FF_DEBUG_ER 0x00000400
1337 #define FF_DEBUG_MMCO 0x00000800
1338 #define FF_DEBUG_BUGS 0x00001000
1339 #define FF_DEBUG_BUFFERS 0x00008000
1340 #define FF_DEBUG_THREADS 0x00010000
1341 #define FF_DEBUG_GREEN_MD 0x00800000
1342 #define FF_DEBUG_NOMC 0x01000000
1343 
1344  /**
1345  * Error recognition; may misdetect some more or less valid parts as errors.
1346  * This is a bitfield of the AV_EF_* values defined in defs.h.
1347  *
1348  * - encoding: Set by user.
1349  * - decoding: Set by user.
1350  */
1352 
1353  /**
1354  * opaque 64-bit number (generally a PTS) that will be reordered and
1355  * output in AVFrame.reordered_opaque
1356  * - encoding: Set by libavcodec to the reordered_opaque of the input
1357  * frame corresponding to the last returned packet. Only
1358  * supported by encoders with the
1359  * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1360  * - decoding: Set by user.
1361  */
1363 
1364  /**
1365  * Hardware accelerator in use
1366  * - encoding: unused.
1367  * - decoding: Set by libavcodec
1368  */
1369  const struct AVHWAccel *hwaccel;
1370 
1371  /**
1372  * Legacy hardware accelerator context.
1373  *
1374  * For some hardware acceleration methods, the caller may use this field to
1375  * signal hwaccel-specific data to the codec. The struct pointed to by this
1376  * pointer is hwaccel-dependent and defined in the respective header. Please
1377  * refer to the FFmpeg HW accelerator documentation to know how to fill
1378  * this.
1379  *
1380  * In most cases this field is optional - the necessary information may also
1381  * be provided to libavcodec through @ref hw_frames_ctx or @ref
1382  * hw_device_ctx (see avcodec_get_hw_config()). However, in some cases it
1383  * may be the only method of signalling some (optional) information.
1384  *
1385  * The struct and its contents are owned by the caller.
1386  *
1387  * - encoding: May be set by the caller before avcodec_open2(). Must remain
1388  * valid until avcodec_free_context().
1389  * - decoding: May be set by the caller in the get_format() callback.
1390  * Must remain valid until the next get_format() call,
1391  * or avcodec_free_context() (whichever comes first).
1392  */
1394 
1395  /**
1396  * error
1397  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1398  * - decoding: unused
1399  */
1401 
1402  /**
1403  * DCT algorithm, see FF_DCT_* below
1404  * - encoding: Set by user.
1405  * - decoding: unused
1406  */
1408 #define FF_DCT_AUTO 0
1409 #define FF_DCT_FASTINT 1
1410 #define FF_DCT_INT 2
1411 #define FF_DCT_MMX 3
1412 #define FF_DCT_ALTIVEC 5
1413 #define FF_DCT_FAAN 6
1414 
1415  /**
1416  * IDCT algorithm, see FF_IDCT_* below.
1417  * - encoding: Set by user.
1418  * - decoding: Set by user.
1419  */
1421 #define FF_IDCT_AUTO 0
1422 #define FF_IDCT_INT 1
1423 #define FF_IDCT_SIMPLE 2
1424 #define FF_IDCT_SIMPLEMMX 3
1425 #define FF_IDCT_ARM 7
1426 #define FF_IDCT_ALTIVEC 8
1427 #define FF_IDCT_SIMPLEARM 10
1428 #define FF_IDCT_XVID 14
1429 #define FF_IDCT_SIMPLEARMV5TE 16
1430 #define FF_IDCT_SIMPLEARMV6 17
1431 #define FF_IDCT_FAAN 20
1432 #define FF_IDCT_SIMPLENEON 22
1433 #if FF_API_IDCT_NONE
1434 // formerly used by xvmc
1435 #define FF_IDCT_NONE 24
1436 #endif
1437 #define FF_IDCT_SIMPLEAUTO 128
1438 
1439  /**
1440  * bits per sample/pixel from the demuxer (needed for huffyuv).
1441  * - encoding: Set by libavcodec.
1442  * - decoding: Set by user.
1443  */
1445 
1446  /**
1447  * Bits per sample/pixel of internal libavcodec pixel/sample format.
1448  * - encoding: set by user.
1449  * - decoding: set by libavcodec.
1450  */
1452 
1453  /**
1454  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1455  * - encoding: unused
1456  * - decoding: Set by user.
1457  */
1458  int lowres;
1459 
1460  /**
1461  * thread count
1462  * is used to decide how many independent tasks should be passed to execute()
1463  * - encoding: Set by user.
1464  * - decoding: Set by user.
1465  */
1467 
1468  /**
1469  * Which multithreading methods to use.
1470  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1471  * so clients which cannot provide future frames should not use it.
1472  *
1473  * - encoding: Set by user, otherwise the default is used.
1474  * - decoding: Set by user, otherwise the default is used.
1475  */
1477 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1478 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1479 
1480  /**
1481  * Which multithreading methods are in use by the codec.
1482  * - encoding: Set by libavcodec.
1483  * - decoding: Set by libavcodec.
1484  */
1486 
1487 #if FF_API_THREAD_SAFE_CALLBACKS
1488  /**
1489  * Set by the client if its custom get_buffer() callback can be called
1490  * synchronously from another thread, which allows faster multithreaded decoding.
1491  * draw_horiz_band() will be called from other threads regardless of this setting.
1492  * Ignored if the default get_buffer() is used.
1493  * - encoding: Set by user.
1494  * - decoding: Set by user.
1495  *
1496  * @deprecated the custom get_buffer2() callback should always be
1497  * thread-safe. Thread-unsafe get_buffer2() implementations will be
1498  * invalid starting with LIBAVCODEC_VERSION_MAJOR=60; in other words,
1499  * libavcodec will behave as if this field was always set to 1.
1500  * Callers that want to be forward compatible with future libavcodec
1501  * versions should wrap access to this field in
1502  * #if LIBAVCODEC_VERSION_MAJOR < 60
1503  */
1506 #endif
1507 
1508  /**
1509  * The codec may call this to execute several independent things.
1510  * It will return only after finishing all tasks.
1511  * The user may replace this with some multithreaded implementation,
1512  * the default implementation will execute the parts serially.
1513  * @param count the number of things to execute
1514  * - encoding: Set by libavcodec, user can override.
1515  * - decoding: Set by libavcodec, user can override.
1516  */
1517  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1518 
1519  /**
1520  * The codec may call this to execute several independent things.
1521  * It will return only after finishing all tasks.
1522  * The user may replace this with some multithreaded implementation,
1523  * the default implementation will execute the parts serially.
1524  * @param c context passed also to func
1525  * @param count the number of things to execute
1526  * @param arg2 argument passed unchanged to func
1527  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1528  * @param func function that will be called count times, with jobnr from 0 to count-1.
1529  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1530  * two instances of func executing at the same time will have the same threadnr.
1531  * @return always 0 currently, but code should handle a future improvement where when any call to func
1532  * returns < 0 no further calls to func may be done and < 0 is returned.
1533  * - encoding: Set by libavcodec, user can override.
1534  * - decoding: Set by libavcodec, user can override.
1535  */
1536  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1537 
1538  /**
1539  * noise vs. sse weight for the nsse comparison function
1540  * - encoding: Set by user.
1541  * - decoding: unused
1542  */
1544 
1545  /**
1546  * profile
1547  * - encoding: Set by user.
1548  * - decoding: Set by libavcodec.
1549  */
1550  int profile;
1551 #define FF_PROFILE_UNKNOWN -99
1552 #define FF_PROFILE_RESERVED -100
1553 
1554 #define FF_PROFILE_AAC_MAIN 0
1555 #define FF_PROFILE_AAC_LOW 1
1556 #define FF_PROFILE_AAC_SSR 2
1557 #define FF_PROFILE_AAC_LTP 3
1558 #define FF_PROFILE_AAC_HE 4
1559 #define FF_PROFILE_AAC_HE_V2 28
1560 #define FF_PROFILE_AAC_LD 22
1561 #define FF_PROFILE_AAC_ELD 38
1562 #define FF_PROFILE_MPEG2_AAC_LOW 128
1563 #define FF_PROFILE_MPEG2_AAC_HE 131
1564 
1565 #define FF_PROFILE_DNXHD 0
1566 #define FF_PROFILE_DNXHR_LB 1
1567 #define FF_PROFILE_DNXHR_SQ 2
1568 #define FF_PROFILE_DNXHR_HQ 3
1569 #define FF_PROFILE_DNXHR_HQX 4
1570 #define FF_PROFILE_DNXHR_444 5
1571 
1572 #define FF_PROFILE_DTS 20
1573 #define FF_PROFILE_DTS_ES 30
1574 #define FF_PROFILE_DTS_96_24 40
1575 #define FF_PROFILE_DTS_HD_HRA 50
1576 #define FF_PROFILE_DTS_HD_MA 60
1577 #define FF_PROFILE_DTS_EXPRESS 70
1578 
1579 #define FF_PROFILE_MPEG2_422 0
1580 #define FF_PROFILE_MPEG2_HIGH 1
1581 #define FF_PROFILE_MPEG2_SS 2
1582 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1583 #define FF_PROFILE_MPEG2_MAIN 4
1584 #define FF_PROFILE_MPEG2_SIMPLE 5
1585 
1586 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1587 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1588 
1589 #define FF_PROFILE_H264_BASELINE 66
1590 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1591 #define FF_PROFILE_H264_MAIN 77
1592 #define FF_PROFILE_H264_EXTENDED 88
1593 #define FF_PROFILE_H264_HIGH 100
1594 #define FF_PROFILE_H264_HIGH_10 110
1595 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1596 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1597 #define FF_PROFILE_H264_HIGH_422 122
1598 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1599 #define FF_PROFILE_H264_STEREO_HIGH 128
1600 #define FF_PROFILE_H264_HIGH_444 144
1601 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1602 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1603 #define FF_PROFILE_H264_CAVLC_444 44
1604 
1605 #define FF_PROFILE_VC1_SIMPLE 0
1606 #define FF_PROFILE_VC1_MAIN 1
1607 #define FF_PROFILE_VC1_COMPLEX 2
1608 #define FF_PROFILE_VC1_ADVANCED 3
1609 
1610 #define FF_PROFILE_MPEG4_SIMPLE 0
1611 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1612 #define FF_PROFILE_MPEG4_CORE 2
1613 #define FF_PROFILE_MPEG4_MAIN 3
1614 #define FF_PROFILE_MPEG4_N_BIT 4
1615 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1616 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1617 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1618 #define FF_PROFILE_MPEG4_HYBRID 8
1619 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1620 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1621 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1622 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1623 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1624 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1625 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1626 
1627 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1628 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1629 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1630 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1631 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1632 
1633 #define FF_PROFILE_VP9_0 0
1634 #define FF_PROFILE_VP9_1 1
1635 #define FF_PROFILE_VP9_2 2
1636 #define FF_PROFILE_VP9_3 3
1637 
1638 #define FF_PROFILE_HEVC_MAIN 1
1639 #define FF_PROFILE_HEVC_MAIN_10 2
1640 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1641 #define FF_PROFILE_HEVC_REXT 4
1642 
1643 #define FF_PROFILE_VVC_MAIN_10 1
1644 #define FF_PROFILE_VVC_MAIN_10_444 33
1645 
1646 #define FF_PROFILE_AV1_MAIN 0
1647 #define FF_PROFILE_AV1_HIGH 1
1648 #define FF_PROFILE_AV1_PROFESSIONAL 2
1649 
1650 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1651 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1652 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1653 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1654 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1655 
1656 #define FF_PROFILE_SBC_MSBC 1
1657 
1658 #define FF_PROFILE_PRORES_PROXY 0
1659 #define FF_PROFILE_PRORES_LT 1
1660 #define FF_PROFILE_PRORES_STANDARD 2
1661 #define FF_PROFILE_PRORES_HQ 3
1662 #define FF_PROFILE_PRORES_4444 4
1663 #define FF_PROFILE_PRORES_XQ 5
1664 
1665 #define FF_PROFILE_ARIB_PROFILE_A 0
1666 #define FF_PROFILE_ARIB_PROFILE_C 1
1667 
1668 #define FF_PROFILE_KLVA_SYNC 0
1669 #define FF_PROFILE_KLVA_ASYNC 1
1670 
1671  /**
1672  * level
1673  * - encoding: Set by user.
1674  * - decoding: Set by libavcodec.
1675  */
1676  int level;
1677 #define FF_LEVEL_UNKNOWN -99
1678 
1679  /**
1680  * Skip loop filtering for selected frames.
1681  * - encoding: unused
1682  * - decoding: Set by user.
1683  */
1685 
1686  /**
1687  * Skip IDCT/dequantization for selected frames.
1688  * - encoding: unused
1689  * - decoding: Set by user.
1690  */
1692 
1693  /**
1694  * Skip decoding for selected frames.
1695  * - encoding: unused
1696  * - decoding: Set by user.
1697  */
1699 
1700  /**
1701  * Header containing style information for text subtitles.
1702  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
1703  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
1704  * the Format line following. It shouldn't include any Dialogue line.
1705  * - encoding: Set/allocated/freed by user (before avcodec_open2())
1706  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
1707  */
1710 
1711  /**
1712  * Audio only. The number of "priming" samples (padding) inserted by the
1713  * encoder at the beginning of the audio. I.e. this number of leading
1714  * decoded samples must be discarded by the caller to get the original audio
1715  * without leading padding.
1716  *
1717  * - decoding: unused
1718  * - encoding: Set by libavcodec. The timestamps on the output packets are
1719  * adjusted by the encoder so that they always refer to the
1720  * first sample of the data actually contained in the packet,
1721  * including any added padding. E.g. if the timebase is
1722  * 1/samplerate and the timestamp of the first input sample is
1723  * 0, the timestamp of the first output packet will be
1724  * -initial_padding.
1725  */
1727 
1728  /**
1729  * - decoding: For codecs that store a framerate value in the compressed
1730  * bitstream, the decoder may export it here. { 0, 1} when
1731  * unknown.
1732  * - encoding: May be used to signal the framerate of CFR content to an
1733  * encoder.
1734  */
1736 
1737  /**
1738  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
1739  * - encoding: unused.
1740  * - decoding: Set by libavcodec before calling get_format()
1741  */
1743 
1744  /**
1745  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
1746  * - encoding unused.
1747  * - decoding set by user.
1748  */
1750 
1751  /**
1752  * AVCodecDescriptor
1753  * - encoding: unused.
1754  * - decoding: set by libavcodec.
1755  */
1757 
1758  /**
1759  * Current statistics for PTS correction.
1760  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
1761  * - encoding: unused
1762  */
1763  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
1764  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
1765  int64_t pts_correction_last_pts; /// PTS of the last frame
1766  int64_t pts_correction_last_dts; /// DTS of the last frame
1767 
1768  /**
1769  * Character encoding of the input subtitles file.
1770  * - decoding: set by user
1771  * - encoding: unused
1772  */
1774 
1775  /**
1776  * Subtitles character encoding mode. Formats or codecs might be adjusting
1777  * this setting (if they are doing the conversion themselves for instance).
1778  * - decoding: set by libavcodec
1779  * - encoding: unused
1780  */
1782 #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)
1783 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
1784 #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
1785 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
1786 
1787  /**
1788  * Skip processing alpha if supported by codec.
1789  * Note that if the format uses pre-multiplied alpha (common with VP6,
1790  * and recommended due to better video quality/compression)
1791  * the image will look as if alpha-blended onto a black background.
1792  * However for formats that do not use pre-multiplied alpha
1793  * there might be serious artefacts (though e.g. libswscale currently
1794  * assumes pre-multiplied alpha anyway).
1795  *
1796  * - decoding: set by user
1797  * - encoding: unused
1798  */
1800 
1801  /**
1802  * Number of samples to skip after a discontinuity
1803  * - decoding: unused
1804  * - encoding: set by libavcodec
1805  */
1807 
1808 #if FF_API_DEBUG_MV
1809  /**
1810  * @deprecated unused
1811  */
1814 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
1815 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
1816 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
1817 #endif
1818 
1819  /**
1820  * custom intra quantization matrix
1821  * - encoding: Set by user, can be NULL.
1822  * - decoding: unused.
1823  */
1825 
1826  /**
1827  * dump format separator.
1828  * can be ", " or "\n " or anything else
1829  * - encoding: Set by user.
1830  * - decoding: Set by user.
1831  */
1832  uint8_t *dump_separator;
1833 
1834  /**
1835  * ',' separated list of allowed decoders.
1836  * If NULL then all are allowed
1837  * - encoding: unused
1838  * - decoding: set by user
1839  */
1841 
1842  /**
1843  * Properties of the stream that gets decoded
1844  * - encoding: unused
1845  * - decoding: set by libavcodec
1846  */
1847  unsigned properties;
1848 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
1849 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
1850 #define FF_CODEC_PROPERTY_FILM_GRAIN 0x00000004
1851 
1852  /**
1853  * Additional data associated with the entire coded stream.
1854  *
1855  * - decoding: unused
1856  * - encoding: may be set by libavcodec after avcodec_open2().
1857  */
1860 
1861  /**
1862  * A reference to the AVHWFramesContext describing the input (for encoding)
1863  * or output (decoding) frames. The reference is set by the caller and
1864  * afterwards owned (and freed) by libavcodec - it should never be read by
1865  * the caller after being set.
1866  *
1867  * - decoding: This field should be set by the caller from the get_format()
1868  * callback. The previous reference (if any) will always be
1869  * unreffed by libavcodec before the get_format() call.
1870  *
1871  * If the default get_buffer2() is used with a hwaccel pixel
1872  * format, then this AVHWFramesContext will be used for
1873  * allocating the frame buffers.
1874  *
1875  * - encoding: For hardware encoders configured to use a hwaccel pixel
1876  * format, this field should be set by the caller to a reference
1877  * to the AVHWFramesContext describing input frames.
1878  * AVHWFramesContext.format must be equal to
1879  * AVCodecContext.pix_fmt.
1880  *
1881  * This field should be set before avcodec_open2() is called.
1882  */
1884 
1885 #if FF_API_SUB_TEXT_FORMAT
1886  /**
1887  * @deprecated unused
1888  */
1891 #define FF_SUB_TEXT_FMT_ASS 0
1892 #endif
1893 
1894  /**
1895  * Audio only. The amount of padding (in samples) appended by the encoder to
1896  * the end of the audio. I.e. this number of decoded samples must be
1897  * discarded by the caller from the end of the stream to get the original
1898  * audio without any trailing padding.
1899  *
1900  * - decoding: unused
1901  * - encoding: unused
1902  */
1904 
1905  /**
1906  * The number of pixels per image to maximally accept.
1907  *
1908  * - decoding: set by user
1909  * - encoding: set by user
1910  */
1911  int64_t max_pixels;
1912 
1913  /**
1914  * A reference to the AVHWDeviceContext describing the device which will
1915  * be used by a hardware encoder/decoder. The reference is set by the
1916  * caller and afterwards owned (and freed) by libavcodec.
1917  *
1918  * This should be used if either the codec device does not require
1919  * hardware frames or any that are used are to be allocated internally by
1920  * libavcodec. If the user wishes to supply any of the frames used as
1921  * encoder input or decoder output then hw_frames_ctx should be used
1922  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
1923  * field will be ignored while decoding the associated stream segment, but
1924  * may again be used on a following one after another get_format() call.
1925  *
1926  * For both encoders and decoders this field should be set before
1927  * avcodec_open2() is called and must not be written to thereafter.
1928  *
1929  * Note that some decoders may require this field to be set initially in
1930  * order to support hw_frames_ctx at all - in that case, all frames
1931  * contexts used must be created on the same device.
1932  */
1934 
1935  /**
1936  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
1937  * decoding (if active).
1938  * - encoding: unused
1939  * - decoding: Set by user (either before avcodec_open2(), or in the
1940  * AVCodecContext.get_format callback)
1941  */
1943 
1944  /**
1945  * Video decoding only. Certain video codecs support cropping, meaning that
1946  * only a sub-rectangle of the decoded frame is intended for display. This
1947  * option controls how cropping is handled by libavcodec.
1948  *
1949  * When set to 1 (the default), libavcodec will apply cropping internally.
1950  * I.e. it will modify the output frame width/height fields and offset the
1951  * data pointers (only by as much as possible while preserving alignment, or
1952  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
1953  * the frames output by the decoder refer only to the cropped area. The
1954  * crop_* fields of the output frames will be zero.
1955  *
1956  * When set to 0, the width/height fields of the output frames will be set
1957  * to the coded dimensions and the crop_* fields will describe the cropping
1958  * rectangle. Applying the cropping is left to the caller.
1959  *
1960  * @warning When hardware acceleration with opaque output frames is used,
1961  * libavcodec is unable to apply cropping from the top/left border.
1962  *
1963  * @note when this option is set to zero, the width/height fields of the
1964  * AVCodecContext and output AVFrames have different meanings. The codec
1965  * context fields store display dimensions (with the coded dimensions in
1966  * coded_width/height), while the frame fields store the coded dimensions
1967  * (with the display dimensions being determined by the crop_* fields).
1968  */
1970 
1971  /*
1972  * Video decoding only. Sets the number of extra hardware frames which
1973  * the decoder will allocate for use by the caller. This must be set
1974  * before avcodec_open2() is called.
1975  *
1976  * Some hardware decoders require all frames that they will use for
1977  * output to be defined in advance before decoding starts. For such
1978  * decoders, the hardware frame pool must therefore be of a fixed size.
1979  * The extra frames set here are on top of any number that the decoder
1980  * needs internally in order to operate normally (for example, frames
1981  * used as reference pictures).
1982  */
1984 
1985  /**
1986  * The percentage of damaged samples to discard a frame.
1987  *
1988  * - decoding: set by user
1989  * - encoding: unused
1990  */
1992 
1993  /**
1994  * The number of samples per frame to maximally accept.
1995  *
1996  * - decoding: set by user
1997  * - encoding: set by user
1998  */
1999  int64_t max_samples;
2000 
2001  /**
2002  * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
2003  * metadata exported in frame, packet, or coded stream side data by
2004  * decoders and encoders.
2005  *
2006  * - decoding: set by user
2007  * - encoding: set by user
2008  */
2010 
2011  /**
2012  * This callback is called at the beginning of each packet to get a data
2013  * buffer for it.
2014  *
2015  * The following field will be set in the packet before this callback is
2016  * called:
2017  * - size
2018  * This callback must use the above value to calculate the required buffer size,
2019  * which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
2020  *
2021  * In some specific cases, the encoder may not use the entire buffer allocated by this
2022  * callback. This will be reflected in the size value in the packet once returned by
2023  * avcodec_receive_packet().
2024  *
2025  * This callback must fill the following fields in the packet:
2026  * - data: alignment requirements for AVPacket apply, if any. Some architectures and
2027  * encoders may benefit from having aligned data.
2028  * - buf: must contain a pointer to an AVBufferRef structure. The packet's
2029  * data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
2030  * and av_buffer_ref().
2031  *
2032  * If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2033  * avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2034  * some other means.
2035  *
2036  * The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2037  * They may be used for example to hint what use the buffer may get after being
2038  * created.
2039  * Implementations of this callback may ignore flags they don't understand.
2040  * If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2041  * (read and/or written to if it is writable) later by libavcodec.
2042  *
2043  * This callback must be thread-safe, as when frame threading is used, it may
2044  * be called from multiple threads simultaneously.
2045  *
2046  * @see avcodec_default_get_encode_buffer()
2047  *
2048  * - encoding: Set by libavcodec, user can override.
2049  * - decoding: unused
2050  */
2052 
2053  /**
2054  * Audio channel layout.
2055  * - encoding: must be set by the caller, to one of AVCodec.ch_layouts.
2056  * - decoding: may be set by the caller if known e.g. from the container.
2057  * The decoder can then override during decoding as needed.
2058  */
2060 } AVCodecContext;
2061 
2062 /**
2063  * @defgroup lavc_hwaccel AVHWAccel
2064  *
2065  * @note Nothing in this structure should be accessed by the user. At some
2066  * point in future it will not be externally visible at all.
2067  *
2068  * @{
2069  */
2070 typedef struct AVHWAccel {
2071  /**
2072  * Name of the hardware accelerated codec.
2073  * The name is globally unique among encoders and among decoders (but an
2074  * encoder and a decoder can share the same name).
2075  */
2076  const char *name;
2077 
2078  /**
2079  * Type of codec implemented by the hardware accelerator.
2080  *
2081  * See AVMEDIA_TYPE_xxx
2082  */
2084 
2085  /**
2086  * Codec implemented by the hardware accelerator.
2087  *
2088  * See AV_CODEC_ID_xxx
2089  */
2091 
2092  /**
2093  * Supported pixel format.
2094  *
2095  * Only hardware accelerated formats are supported here.
2096  */
2098 
2099  /**
2100  * Hardware accelerated codec capabilities.
2101  * see AV_HWACCEL_CODEC_CAP_*
2102  */
2104 
2105  /*****************************************************************
2106  * No fields below this line are part of the public API. They
2107  * may not be used outside of libavcodec and can be changed and
2108  * removed at will.
2109  * New public fields should be added right above.
2110  *****************************************************************
2111  */
2112 
2113  /**
2114  * Allocate a custom buffer
2115  */
2117 
2118  /**
2119  * Called at the beginning of each frame or field picture.
2120  *
2121  * Meaningful frame information (codec specific) is guaranteed to
2122  * be parsed at this point. This function is mandatory.
2123  *
2124  * Note that buf can be NULL along with buf_size set to 0.
2125  * Otherwise, this means the whole frame is available at this point.
2126  *
2127  * @param avctx the codec context
2128  * @param buf the frame data buffer base
2129  * @param buf_size the size of the frame in bytes
2130  * @return zero if successful, a negative value otherwise
2131  */
2132  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2133 
2134  /**
2135  * Callback for parameter data (SPS/PPS/VPS etc).
2136  *
2137  * Useful for hardware decoders which keep persistent state about the
2138  * video parameters, and need to receive any changes to update that state.
2139  *
2140  * @param avctx the codec context
2141  * @param type the nal unit type
2142  * @param buf the nal unit data buffer
2143  * @param buf_size the size of the nal unit in bytes
2144  * @return zero if successful, a negative value otherwise
2145  */
2146  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
2147 
2148  /**
2149  * Callback for each slice.
2150  *
2151  * Meaningful slice information (codec specific) is guaranteed to
2152  * be parsed at this point. This function is mandatory.
2153  *
2154  * @param avctx the codec context
2155  * @param buf the slice data buffer base
2156  * @param buf_size the size of the slice in bytes
2157  * @return zero if successful, a negative value otherwise
2158  */
2159  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2160 
2161  /**
2162  * Called at the end of each frame or field picture.
2163  *
2164  * The whole picture is parsed at this point and can now be sent
2165  * to the hardware accelerator. This function is mandatory.
2166  *
2167  * @param avctx the codec context
2168  * @return zero if successful, a negative value otherwise
2169  */
2171 
2172  /**
2173  * Size of per-frame hardware accelerator private data.
2174  *
2175  * Private data is allocated with av_mallocz() before
2176  * AVCodecContext.get_buffer() and deallocated after
2177  * AVCodecContext.release_buffer().
2178  */
2180 
2181  /**
2182  * Initialize the hwaccel private data.
2183  *
2184  * This will be called from ff_get_format(), after hwaccel and
2185  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
2186  * is allocated.
2187  */
2189 
2190  /**
2191  * Uninitialize the hwaccel private data.
2192  *
2193  * This will be called from get_format() or avcodec_close(), after hwaccel
2194  * and hwaccel_context are already uninitialized.
2195  */
2197 
2198  /**
2199  * Size of the private data to allocate in
2200  * AVCodecInternal.hwaccel_priv_data.
2201  */
2203 
2204  /**
2205  * Internal hwaccel capabilities.
2206  */
2208 
2209  /**
2210  * Fill the given hw_frames context with current codec parameters. Called
2211  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
2212  * details.
2213  *
2214  * This CAN be called before AVHWAccel.init is called, and you must assume
2215  * that avctx->hwaccel_priv_data is invalid.
2216  */
2217  int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
2218 } AVHWAccel;
2219 
2220 /**
2221  * HWAccel is experimental and is thus avoided in favor of non experimental
2222  * codecs
2223  */
2224 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2225 
2226 /**
2227  * Hardware acceleration should be used for decoding even if the codec level
2228  * used is unknown or higher than the maximum supported level reported by the
2229  * hardware driver.
2230  *
2231  * It's generally a good idea to pass this flag unless you have a specific
2232  * reason not to, as hardware tends to under-report supported levels.
2233  */
2234 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2235 
2236 /**
2237  * Hardware acceleration can output YUV pixel formats with a different chroma
2238  * sampling than 4:2:0 and/or other than 8 bits per component.
2239  */
2240 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2241 
2242 /**
2243  * Hardware acceleration should still be attempted for decoding when the
2244  * codec profile does not match the reported capabilities of the hardware.
2245  *
2246  * For example, this can be used to try to decode baseline profile H.264
2247  * streams in hardware - it will often succeed, because many streams marked
2248  * as baseline profile actually conform to constrained baseline profile.
2249  *
2250  * @warning If the stream is actually not supported then the behaviour is
2251  * undefined, and may include returning entirely incorrect output
2252  * while indicating success.
2253  */
2254 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2255 
2256 /**
2257  * @}
2258  */
2259 
2262 
2263  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2264 
2265  /**
2266  * Plain text, the text field must be set by the decoder and is
2267  * authoritative. ass and pict fields may contain approximations.
2268  */
2270 
2271  /**
2272  * Formatted text, the ass field must be set by the decoder and is
2273  * authoritative. pict and text fields may contain approximations.
2274  */
2276 };
2277 
2278 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
2279 
2280 typedef struct AVSubtitleRect {
2281  int x; ///< top left corner of pict, undefined when pict is not set
2282  int y; ///< top left corner of pict, undefined when pict is not set
2283  int w; ///< width of pict, undefined when pict is not set
2284  int h; ///< height of pict, undefined when pict is not set
2285  int nb_colors; ///< number of colors in pict, undefined when pict is not set
2286 
2287  /**
2288  * data+linesize for the bitmap of this subtitle.
2289  * Can be set for text/ass as well once they are rendered.
2290  */
2291  uint8_t *data[4];
2292  int linesize[4];
2293 
2295 
2296  char *text; ///< 0 terminated plain UTF-8 text
2297 
2298  /**
2299  * 0 terminated ASS/SSA compatible event line.
2300  * The presentation of this is unaffected by the other values in this
2301  * struct.
2302  */
2303  char *ass;
2304 
2305  int flags;
2306 } AVSubtitleRect;
2307 
2308 typedef struct AVSubtitle {
2309  uint16_t format; /* 0 = graphics */
2310  uint32_t start_display_time; /* relative to packet pts, in ms */
2311  uint32_t end_display_time; /* relative to packet pts, in ms */
2312  unsigned num_rects;
2314  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2315 } AVSubtitle;
2316 
2317 /**
2318  * Return the LIBAVCODEC_VERSION_INT constant.
2319  */
2320 unsigned avcodec_version(void);
2321 
2322 /**
2323  * Return the libavcodec build-time configuration.
2324  */
2325 const char *avcodec_configuration(void);
2326 
2327 /**
2328  * Return the libavcodec license.
2329  */
2330 const char *avcodec_license(void);
2331 
2332 /**
2333  * Allocate an AVCodecContext and set its fields to default values. The
2334  * resulting struct should be freed with avcodec_free_context().
2335  *
2336  * @param codec if non-NULL, allocate private data and initialize defaults
2337  * for the given codec. It is illegal to then call avcodec_open2()
2338  * with a different codec.
2339  * If NULL, then the codec-specific defaults won't be initialized,
2340  * which may result in suboptimal default settings (this is
2341  * important mainly for encoders, e.g. libx264).
2342  *
2343  * @return An AVCodecContext filled with default values or NULL on failure.
2344  */
2346 
2347 /**
2348  * Free the codec context and everything associated with it and write NULL to
2349  * the provided pointer.
2350  */
2351 void avcodec_free_context(AVCodecContext **avctx);
2352 
2353 /**
2354  * Get the AVClass for AVCodecContext. It can be used in combination with
2355  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2356  *
2357  * @see av_opt_find().
2358  */
2359 const AVClass *avcodec_get_class(void);
2360 
2361 #if FF_API_GET_FRAME_CLASS
2362 /**
2363  * @deprecated This function should not be used.
2364  */
2366 const AVClass *avcodec_get_frame_class(void);
2367 #endif
2368 
2369 /**
2370  * Get the AVClass for AVSubtitleRect. It can be used in combination with
2371  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2372  *
2373  * @see av_opt_find().
2374  */
2376 
2377 /**
2378  * Fill the parameters struct based on the values from the supplied codec
2379  * context. Any allocated fields in par are freed and replaced with duplicates
2380  * of the corresponding fields in codec.
2381  *
2382  * @return >= 0 on success, a negative AVERROR code on failure
2383  */
2385  const AVCodecContext *codec);
2386 
2387 /**
2388  * Fill the codec context based on the values from the supplied codec
2389  * parameters. Any allocated fields in codec that have a corresponding field in
2390  * par are freed and replaced with duplicates of the corresponding field in par.
2391  * Fields in codec that do not have a counterpart in par are not touched.
2392  *
2393  * @return >= 0 on success, a negative AVERROR code on failure.
2394  */
2396  const AVCodecParameters *par);
2397 
2398 /**
2399  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2400  * function the context has to be allocated with avcodec_alloc_context3().
2401  *
2402  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2403  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2404  * retrieving a codec.
2405  *
2406  * @note Always call this function before using decoding routines (such as
2407  * @ref avcodec_receive_frame()).
2408  *
2409  * @code
2410  * av_dict_set(&opts, "b", "2.5M", 0);
2411  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2412  * if (!codec)
2413  * exit(1);
2414  *
2415  * context = avcodec_alloc_context3(codec);
2416  *
2417  * if (avcodec_open2(context, codec, opts) < 0)
2418  * exit(1);
2419  * @endcode
2420  *
2421  * @param avctx The context to initialize.
2422  * @param codec The codec to open this context for. If a non-NULL codec has been
2423  * previously passed to avcodec_alloc_context3() or
2424  * for this context, then this parameter MUST be either NULL or
2425  * equal to the previously passed codec.
2426  * @param options A dictionary filled with AVCodecContext and codec-private options.
2427  * On return this object will be filled with options that were not found.
2428  *
2429  * @return zero on success, a negative value on error
2430  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2431  * av_dict_set(), av_opt_find().
2432  */
2433 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2434 
2435 /**
2436  * Close a given AVCodecContext and free all the data associated with it
2437  * (but not the AVCodecContext itself).
2438  *
2439  * Calling this function on an AVCodecContext that hasn't been opened will free
2440  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2441  * codec. Subsequent calls will do nothing.
2442  *
2443  * @note Do not use this function. Use avcodec_free_context() to destroy a
2444  * codec context (either open or closed). Opening and closing a codec context
2445  * multiple times is not supported anymore -- use multiple codec contexts
2446  * instead.
2447  */
2448 int avcodec_close(AVCodecContext *avctx);
2449 
2450 /**
2451  * Free all allocated data in the given subtitle struct.
2452  *
2453  * @param sub AVSubtitle to free.
2454  */
2456 
2457 /**
2458  * @}
2459  */
2460 
2461 /**
2462  * @addtogroup lavc_decoding
2463  * @{
2464  */
2465 
2466 /**
2467  * The default callback for AVCodecContext.get_buffer2(). It is made public so
2468  * it can be called by custom get_buffer2() implementations for decoders without
2469  * AV_CODEC_CAP_DR1 set.
2470  */
2472 
2473 /**
2474  * The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2475  * it can be called by custom get_encode_buffer() implementations for encoders without
2476  * AV_CODEC_CAP_DR1 set.
2477  */
2479 
2480 /**
2481  * Modify width and height values so that they will result in a memory
2482  * buffer that is acceptable for the codec if you do not use any horizontal
2483  * padding.
2484  *
2485  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2486  */
2488 
2489 /**
2490  * Modify width and height values so that they will result in a memory
2491  * buffer that is acceptable for the codec if you also ensure that all
2492  * line sizes are a multiple of the respective linesize_align[i].
2493  *
2494  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2495  */
2497  int linesize_align[AV_NUM_DATA_POINTERS]);
2498 
2499 #ifdef FF_API_AVCODEC_CHROMA_POS
2500 /**
2501  * Converts AVChromaLocation to swscale x/y chroma position.
2502  *
2503  * The positions represent the chroma (0,0) position in a coordinates system
2504  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2505  *
2506  * @param xpos horizontal chroma sample position
2507  * @param ypos vertical chroma sample position
2508  * @deprecated Use av_chroma_location_enum_to_pos() instead.
2509  */
2511 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
2512 
2513 /**
2514  * Converts swscale x/y chroma position to AVChromaLocation.
2515  *
2516  * The positions represent the chroma (0,0) position in a coordinates system
2517  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2518  *
2519  * @param xpos horizontal chroma sample position
2520  * @param ypos vertical chroma sample position
2521  * @deprecated Use av_chroma_location_pos_to_enum() instead.
2522  */
2524 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
2525 #endif
2526 
2527 /**
2528  * Decode a subtitle message.
2529  * Return a negative value on error, otherwise return the number of bytes used.
2530  * If no subtitle could be decompressed, got_sub_ptr is zero.
2531  * Otherwise, the subtitle is stored in *sub.
2532  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
2533  * simplicity, because the performance difference is expected to be negligible
2534  * and reusing a get_buffer written for video codecs would probably perform badly
2535  * due to a potentially very different allocation pattern.
2536  *
2537  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2538  * and output. This means that for some packets they will not immediately
2539  * produce decoded output and need to be flushed at the end of decoding to get
2540  * all the decoded data. Flushing is done by calling this function with packets
2541  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2542  * returning subtitles. It is safe to flush even those decoders that are not
2543  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
2544  *
2545  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2546  * before packets may be fed to the decoder.
2547  *
2548  * @param avctx the codec context
2549  * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
2550  * must be freed with avsubtitle_free if *got_sub_ptr is set.
2551  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
2552  * @param[in] avpkt The input AVPacket containing the input buffer.
2553  */
2555  int *got_sub_ptr,
2556  AVPacket *avpkt);
2557 
2558 /**
2559  * Supply raw packet data as input to a decoder.
2560  *
2561  * Internally, this call will copy relevant AVCodecContext fields, which can
2562  * influence decoding per-packet, and apply them when the packet is actually
2563  * decoded. (For example AVCodecContext.skip_frame, which might direct the
2564  * decoder to drop the frame contained by the packet sent with this function.)
2565  *
2566  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2567  * larger than the actual read bytes because some optimized bitstream
2568  * readers read 32 or 64 bits at once and could read over the end.
2569  *
2570  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2571  * before packets may be fed to the decoder.
2572  *
2573  * @param avctx codec context
2574  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
2575  * frame, or several complete audio frames.
2576  * Ownership of the packet remains with the caller, and the
2577  * decoder will not write to the packet. The decoder may create
2578  * a reference to the packet data (or copy it if the packet is
2579  * not reference-counted).
2580  * Unlike with older APIs, the packet is always fully consumed,
2581  * and if it contains multiple frames (e.g. some audio codecs),
2582  * will require you to call avcodec_receive_frame() multiple
2583  * times afterwards before you can send a new packet.
2584  * It can be NULL (or an AVPacket with data set to NULL and
2585  * size set to 0); in this case, it is considered a flush
2586  * packet, which signals the end of the stream. Sending the
2587  * first flush packet will return success. Subsequent ones are
2588  * unnecessary and will return AVERROR_EOF. If the decoder
2589  * still has frames buffered, it will return them after sending
2590  * a flush packet.
2591  *
2592  * @return 0 on success, otherwise negative error code:
2593  * AVERROR(EAGAIN): input is not accepted in the current state - user
2594  * must read output with avcodec_receive_frame() (once
2595  * all output is read, the packet should be resent, and
2596  * the call will not fail with EAGAIN).
2597  * AVERROR_EOF: the decoder has been flushed, and no new packets can
2598  * be sent to it (also returned if more than 1 flush
2599  * packet is sent)
2600  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
2601  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
2602  * other errors: legitimate decoding errors
2603  */
2604 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
2605 
2606 /**
2607  * Return decoded output data from a decoder or encoder (when the
2608  * AV_CODEC_FLAG_RECON_FRAME flag is used).
2609  *
2610  * @param avctx codec context
2611  * @param frame This will be set to a reference-counted video or audio
2612  * frame (depending on the decoder type) allocated by the
2613  * codec. Note that the function will always call
2614  * av_frame_unref(frame) before doing anything else.
2615  *
2616  * @return
2617  * 0: success, a frame was returned
2618  * AVERROR(EAGAIN): output is not available in this state - user must try
2619  * to send new input
2620  * AVERROR_EOF: the codec has been fully flushed, and there will be
2621  * no more output frames
2622  * AVERROR(EINVAL): codec not opened, or it is an encoder without
2623  * the AV_CODEC_FLAG_RECON_FRAME flag enabled
2624  * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
2625  * with respect to first decoded frame. Applicable
2626  * when flag AV_CODEC_FLAG_DROPCHANGED is set.
2627  * other negative values: legitimate decoding errors
2628  */
2630 
2631 /**
2632  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
2633  * to retrieve buffered output packets.
2634  *
2635  * @param avctx codec context
2636  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
2637  * Ownership of the frame remains with the caller, and the
2638  * encoder will not write to the frame. The encoder may create
2639  * a reference to the frame data (or copy it if the frame is
2640  * not reference-counted).
2641  * It can be NULL, in which case it is considered a flush
2642  * packet. This signals the end of the stream. If the encoder
2643  * still has packets buffered, it will return them after this
2644  * call. Once flushing mode has been entered, additional flush
2645  * packets are ignored, and sending frames will return
2646  * AVERROR_EOF.
2647  *
2648  * For audio:
2649  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
2650  * can have any number of samples.
2651  * If it is not set, frame->nb_samples must be equal to
2652  * avctx->frame_size for all frames except the last.
2653  * The final frame may be smaller than avctx->frame_size.
2654  * @return 0 on success, otherwise negative error code:
2655  * AVERROR(EAGAIN): input is not accepted in the current state - user
2656  * must read output with avcodec_receive_packet() (once
2657  * all output is read, the packet should be resent, and
2658  * the call will not fail with EAGAIN).
2659  * AVERROR_EOF: the encoder has been flushed, and no new frames can
2660  * be sent to it
2661  * AVERROR(EINVAL): codec not opened, it is a decoder, or requires flush
2662  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
2663  * other errors: legitimate encoding errors
2664  */
2665 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
2666 
2667 /**
2668  * Read encoded data from the encoder.
2669  *
2670  * @param avctx codec context
2671  * @param avpkt This will be set to a reference-counted packet allocated by the
2672  * encoder. Note that the function will always call
2673  * av_packet_unref(avpkt) before doing anything else.
2674  * @return 0 on success, otherwise negative error code:
2675  * AVERROR(EAGAIN): output is not available in the current state - user
2676  * must try to send input
2677  * AVERROR_EOF: the encoder has been fully flushed, and there will be
2678  * no more output packets
2679  * AVERROR(EINVAL): codec not opened, or it is a decoder
2680  * other errors: legitimate encoding errors
2681  */
2682 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
2683 
2684 /**
2685  * Create and return a AVHWFramesContext with values adequate for hardware
2686  * decoding. This is meant to get called from the get_format callback, and is
2687  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
2688  * This API is for decoding with certain hardware acceleration modes/APIs only.
2689  *
2690  * The returned AVHWFramesContext is not initialized. The caller must do this
2691  * with av_hwframe_ctx_init().
2692  *
2693  * Calling this function is not a requirement, but makes it simpler to avoid
2694  * codec or hardware API specific details when manually allocating frames.
2695  *
2696  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
2697  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
2698  * it unnecessary to call this function or having to care about
2699  * AVHWFramesContext initialization at all.
2700  *
2701  * There are a number of requirements for calling this function:
2702  *
2703  * - It must be called from get_format with the same avctx parameter that was
2704  * passed to get_format. Calling it outside of get_format is not allowed, and
2705  * can trigger undefined behavior.
2706  * - The function is not always supported (see description of return values).
2707  * Even if this function returns successfully, hwaccel initialization could
2708  * fail later. (The degree to which implementations check whether the stream
2709  * is actually supported varies. Some do this check only after the user's
2710  * get_format callback returns.)
2711  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
2712  * user decides to use a AVHWFramesContext prepared with this API function,
2713  * the user must return the same hw_pix_fmt from get_format.
2714  * - The device_ref passed to this function must support the given hw_pix_fmt.
2715  * - After calling this API function, it is the user's responsibility to
2716  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
2717  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
2718  * before returning from get_format (this is implied by the normal
2719  * AVCodecContext.hw_frames_ctx API rules).
2720  * - The AVHWFramesContext parameters may change every time time get_format is
2721  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
2722  * you are inherently required to go through this process again on every
2723  * get_format call.
2724  * - It is perfectly possible to call this function without actually using
2725  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
2726  * previously initialized AVHWFramesContext, and calling this API function
2727  * only to test whether the required frame parameters have changed.
2728  * - Fields that use dynamically allocated values of any kind must not be set
2729  * by the user unless setting them is explicitly allowed by the documentation.
2730  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
2731  * the new free callback must call the potentially set previous free callback.
2732  * This API call may set any dynamically allocated fields, including the free
2733  * callback.
2734  *
2735  * The function will set at least the following fields on AVHWFramesContext
2736  * (potentially more, depending on hwaccel API):
2737  *
2738  * - All fields set by av_hwframe_ctx_alloc().
2739  * - Set the format field to hw_pix_fmt.
2740  * - Set the sw_format field to the most suited and most versatile format. (An
2741  * implication is that this will prefer generic formats over opaque formats
2742  * with arbitrary restrictions, if possible.)
2743  * - Set the width/height fields to the coded frame size, rounded up to the
2744  * API-specific minimum alignment.
2745  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
2746  * field to the number of maximum reference surfaces possible with the codec,
2747  * plus 1 surface for the user to work (meaning the user can safely reference
2748  * at most 1 decoded surface at a time), plus additional buffering introduced
2749  * by frame threading. If the hwaccel does not require pre-allocation, the
2750  * field is left to 0, and the decoder will allocate new surfaces on demand
2751  * during decoding.
2752  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
2753  * hardware API.
2754  *
2755  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
2756  * with basic frame parameters set.
2757  *
2758  * The function is stateless, and does not change the AVCodecContext or the
2759  * device_ref AVHWDeviceContext.
2760  *
2761  * @param avctx The context which is currently calling get_format, and which
2762  * implicitly contains all state needed for filling the returned
2763  * AVHWFramesContext properly.
2764  * @param device_ref A reference to the AVHWDeviceContext describing the device
2765  * which will be used by the hardware decoder.
2766  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
2767  * @param out_frames_ref On success, set to a reference to an _uninitialized_
2768  * AVHWFramesContext, created from the given device_ref.
2769  * Fields will be set to values required for decoding.
2770  * Not changed if an error is returned.
2771  * @return zero on success, a negative value on error. The following error codes
2772  * have special semantics:
2773  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
2774  * is always manual, or it is a decoder which does not
2775  * support setting AVCodecContext.hw_frames_ctx at all,
2776  * or it is a software format.
2777  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
2778  * this configuration, or the device_ref is not supported
2779  * for the hwaccel referenced by hw_pix_fmt.
2780  */
2782  AVBufferRef *device_ref,
2784  AVBufferRef **out_frames_ref);
2785 
2786 
2787 
2788 /**
2789  * @defgroup lavc_parsing Frame parsing
2790  * @{
2791  */
2792 
2795  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
2796  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
2797  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
2798 };
2799 
2800 typedef struct AVCodecParserContext {
2801  void *priv_data;
2802  const struct AVCodecParser *parser;
2803  int64_t frame_offset; /* offset of the current frame */
2804  int64_t cur_offset; /* current offset
2805  (incremented by each av_parser_parse()) */
2806  int64_t next_frame_offset; /* offset of the next frame */
2807  /* video info */
2808  int pict_type; /* XXX: Put it back in AVCodecContext. */
2809  /**
2810  * This field is used for proper frame duration computation in lavf.
2811  * It signals, how much longer the frame duration of the current frame
2812  * is compared to normal frame duration.
2813  *
2814  * frame_duration = (1 + repeat_pict) * time_base
2815  *
2816  * It is used by codecs like H.264 to display telecined material.
2817  */
2818  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
2819  int64_t pts; /* pts of the current frame */
2820  int64_t dts; /* dts of the current frame */
2821 
2822  /* private data */
2823  int64_t last_pts;
2824  int64_t last_dts;
2826 
2827 #define AV_PARSER_PTS_NB 4
2832 
2833  int flags;
2834 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
2835 #define PARSER_FLAG_ONCE 0x0002
2836 /// Set if the parser has a valid file offset
2837 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
2838 #define PARSER_FLAG_USE_CODEC_TS 0x1000
2839 
2840  int64_t offset; ///< byte offset from starting packet start
2842 
2843  /**
2844  * Set by parser to 1 for key frames and 0 for non-key frames.
2845  * It is initialized to -1, so if the parser doesn't set this flag,
2846  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
2847  * will be used.
2848  */
2850 
2851  // Timestamp generation support:
2852  /**
2853  * Synchronization point for start of timestamp generation.
2854  *
2855  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
2856  * (default).
2857  *
2858  * For example, this corresponds to presence of H.264 buffering period
2859  * SEI message.
2860  */
2862 
2863  /**
2864  * Offset of the current timestamp against last timestamp sync point in
2865  * units of AVCodecContext.time_base.
2866  *
2867  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2868  * contain a valid timestamp offset.
2869  *
2870  * Note that the timestamp of sync point has usually a nonzero
2871  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
2872  * the next frame after timestamp sync point will be usually 1.
2873  *
2874  * For example, this corresponds to H.264 cpb_removal_delay.
2875  */
2877 
2878  /**
2879  * Presentation delay of current frame in units of AVCodecContext.time_base.
2880  *
2881  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2882  * contain valid non-negative timestamp delta (presentation time of a frame
2883  * must not lie in the past).
2884  *
2885  * This delay represents the difference between decoding and presentation
2886  * time of the frame.
2887  *
2888  * For example, this corresponds to H.264 dpb_output_delay.
2889  */
2891 
2892  /**
2893  * Position of the packet in file.
2894  *
2895  * Analogous to cur_frame_pts/dts
2896  */
2898 
2899  /**
2900  * Byte position of currently parsed frame in stream.
2901  */
2902  int64_t pos;
2903 
2904  /**
2905  * Previous frame byte position.
2906  */
2907  int64_t last_pos;
2908 
2909  /**
2910  * Duration of the current frame.
2911  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
2912  * For all other types, this is in units of AVCodecContext.time_base.
2913  */
2915 
2917 
2918  /**
2919  * Indicate whether a picture is coded as a frame, top field or bottom field.
2920  *
2921  * For example, H.264 field_pic_flag equal to 0 corresponds to
2922  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
2923  * equal to 1 and bottom_field_flag equal to 0 corresponds to
2924  * AV_PICTURE_STRUCTURE_TOP_FIELD.
2925  */
2927 
2928  /**
2929  * Picture number incremented in presentation or output order.
2930  * This field may be reinitialized at the first picture of a new sequence.
2931  *
2932  * For example, this corresponds to H.264 PicOrderCnt.
2933  */
2935 
2936  /**
2937  * Dimensions of the decoded video intended for presentation.
2938  */
2939  int width;
2940  int height;
2941 
2942  /**
2943  * Dimensions of the coded video.
2944  */
2947 
2948  /**
2949  * The format of the coded data, corresponds to enum AVPixelFormat for video
2950  * and for enum AVSampleFormat for audio.
2951  *
2952  * Note that a decoder can have considerable freedom in how exactly it
2953  * decodes the data, so the format reported here might be different from the
2954  * one returned by a decoder.
2955  */
2956  int format;
2958 
2959 typedef struct AVCodecParser {
2960  int codec_ids[7]; /* several codec IDs are permitted */
2963  /* This callback never returns an error, a negative value means that
2964  * the frame start was in a previous packet. */
2966  AVCodecContext *avctx,
2967  const uint8_t **poutbuf, int *poutbuf_size,
2968  const uint8_t *buf, int buf_size);
2970  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
2971 } AVCodecParser;
2972 
2973 /**
2974  * Iterate over all registered codec parsers.
2975  *
2976  * @param opaque a pointer where libavcodec will store the iteration state. Must
2977  * point to NULL to start the iteration.
2978  *
2979  * @return the next registered codec parser or NULL when the iteration is
2980  * finished
2981  */
2982 const AVCodecParser *av_parser_iterate(void **opaque);
2983 
2985 
2986 /**
2987  * Parse a packet.
2988  *
2989  * @param s parser context.
2990  * @param avctx codec context.
2991  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
2992  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
2993  * @param buf input buffer.
2994  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
2995  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
2996  To signal EOF, this should be 0 (so that the last frame
2997  can be output).
2998  * @param pts input presentation timestamp.
2999  * @param dts input decoding timestamp.
3000  * @param pos input byte position in stream.
3001  * @return the number of bytes of the input bitstream used.
3002  *
3003  * Example:
3004  * @code
3005  * while(in_len){
3006  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
3007  * in_data, in_len,
3008  * pts, dts, pos);
3009  * in_data += len;
3010  * in_len -= len;
3011  *
3012  * if(size)
3013  * decode_frame(data, size);
3014  * }
3015  * @endcode
3016  */
3018  AVCodecContext *avctx,
3019  uint8_t **poutbuf, int *poutbuf_size,
3020  const uint8_t *buf, int buf_size,
3021  int64_t pts, int64_t dts,
3022  int64_t pos);
3023 
3025 
3026 /**
3027  * @}
3028  * @}
3029  */
3030 
3031 /**
3032  * @addtogroup lavc_encoding
3033  * @{
3034  */
3035 
3036 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3037  const AVSubtitle *sub);
3038 
3039 
3040 /**
3041  * @}
3042  */
3043 
3044 /**
3045  * @defgroup lavc_misc Utility functions
3046  * @ingroup libavc
3047  *
3048  * Miscellaneous utility functions related to both encoding and decoding
3049  * (or neither).
3050  * @{
3051  */
3052 
3053 /**
3054  * @defgroup lavc_misc_pixfmt Pixel formats
3055  *
3056  * Functions for working with pixel formats.
3057  * @{
3058  */
3059 
3060 /**
3061  * Return a value representing the fourCC code associated to the
3062  * pixel format pix_fmt, or 0 if no associated fourCC code can be
3063  * found.
3064  */
3066 
3067 /**
3068  * Find the best pixel format to convert to given a certain source pixel
3069  * format. When converting from one pixel format to another, information loss
3070  * may occur. For example, when converting from RGB24 to GRAY, the color
3071  * information will be lost. Similarly, other losses occur when converting from
3072  * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
3073  * the given pixel formats should be used to suffer the least amount of loss.
3074  * The pixel formats from which it chooses one, are determined by the
3075  * pix_fmt_list parameter.
3076  *
3077  *
3078  * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
3079  * @param[in] src_pix_fmt source pixel format
3080  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
3081  * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
3082  * @return The best pixel format to convert to or -1 if none was found.
3083  */
3084 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
3085  enum AVPixelFormat src_pix_fmt,
3086  int has_alpha, int *loss_ptr);
3087 
3089 
3090 /**
3091  * @}
3092  */
3093 
3094 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
3095 
3096 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
3097 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
3098 //FIXME func typedef
3099 
3100 /**
3101  * Fill AVFrame audio data and linesize pointers.
3102  *
3103  * The buffer buf must be a preallocated buffer with a size big enough
3104  * to contain the specified samples amount. The filled AVFrame data
3105  * pointers will point to this buffer.
3106  *
3107  * AVFrame extended_data channel pointers are allocated if necessary for
3108  * planar audio.
3109  *
3110  * @param frame the AVFrame
3111  * frame->nb_samples must be set prior to calling the
3112  * function. This function fills in frame->data,
3113  * frame->extended_data, frame->linesize[0].
3114  * @param nb_channels channel count
3115  * @param sample_fmt sample format
3116  * @param buf buffer to use for frame data
3117  * @param buf_size size of buffer
3118  * @param align plane size sample alignment (0 = default)
3119  * @return >=0 on success, negative error code on failure
3120  * @todo return the size in bytes required to store the samples in
3121  * case of success, at the next libavutil bump
3122  */
3123 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
3124  enum AVSampleFormat sample_fmt, const uint8_t *buf,
3125  int buf_size, int align);
3126 
3127 /**
3128  * Reset the internal codec state / flush internal buffers. Should be called
3129  * e.g. when seeking or when switching to a different stream.
3130  *
3131  * @note for decoders, this function just releases any references the decoder
3132  * might keep internally, but the caller's references remain valid.
3133  *
3134  * @note for encoders, this function will only do something if the encoder
3135  * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3136  * will drain any remaining packets, and can then be re-used for a different
3137  * stream (as opposed to sending a null frame which will leave the encoder
3138  * in a permanent EOF state after draining). This can be desirable if the
3139  * cost of tearing down and replacing the encoder instance is high.
3140  */
3142 
3143 /**
3144  * Return audio frame duration.
3145  *
3146  * @param avctx codec context
3147  * @param frame_bytes size of the frame, or 0 if unknown
3148  * @return frame duration, in samples, if known. 0 if not able to
3149  * determine.
3150  */
3151 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
3152 
3153 /* memory */
3154 
3155 /**
3156  * Same behaviour av_fast_malloc but the buffer has additional
3157  * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
3158  *
3159  * In addition the whole buffer will initially and after resizes
3160  * be 0-initialized so that no uninitialized data will ever appear.
3161  */
3162 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
3163 
3164 /**
3165  * Same behaviour av_fast_padded_malloc except that buffer will always
3166  * be 0-initialized after call.
3167  */
3168 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
3169 
3170 /**
3171  * @return a positive value if s is open (i.e. avcodec_open2() was called on it
3172  * with no corresponding avcodec_close()), 0 otherwise.
3173  */
3175 
3176 /**
3177  * @}
3178  */
3179 
3180 #endif /* AVCODEC_AVCODEC_H */
AVSubtitle
Definition: avcodec.h:2308
avcodec_close
int avcodec_close(AVCodecContext *avctx)
Close a given AVCodecContext and free all the data associated with it (but not the AVCodecContext its...
Definition: avcodec.c:434
func
int(* func)(AVBPrint *dst, const char *in, const char *arg)
Definition: jacosubdec.c:68
avcodec_encode_subtitle
int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size, const AVSubtitle *sub)
Definition: encode.c:164
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1035
AVCodecContext::hwaccel
const struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:1369
AVCodec
AVCodec.
Definition: codec.h:204
AVCodecContext::hwaccel_context
void * hwaccel_context
Legacy hardware accelerator context.
Definition: avcodec.h:1393
hw_pix_fmt
static enum AVPixelFormat hw_pix_fmt
Definition: hw_decode.c:46
avcodec_enum_to_chroma_pos
attribute_deprecated int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos)
Converts AVChromaLocation to swscale x/y chroma position.
Definition: utils.c:357
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVCodecParserContext::pts
int64_t pts
Definition: avcodec.h:2819
AVCodecContext::log_level_offset
int log_level_offset
Definition: avcodec.h:404
AVCodecContext::keyint_min
int keyint_min
minimum GOP size
Definition: avcodec.h:940
avcodec_receive_packet
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:478
AVCodecContext::workaround_bugs
int workaround_bugs
Work around bugs in encoders which sometimes cannot be detected automatically.
Definition: avcodec.h:1280
AVSubtitle::rects
AVSubtitleRect ** rects
Definition: avcodec.h:2313
AVCodecContext::get_format
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Callback to negotiate the pixel format.
Definition: avcodec.h:662
AVCodecParserContext::dts_sync_point
int dts_sync_point
Synchronization point for start of timestamp generation.
Definition: avcodec.h:2861
AVCodecContext::audio_service_type
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:1086
AVCodecContext::colorspace
enum AVColorSpace colorspace
YUV colorspace type.
Definition: avcodec.h:975
AVColorTransferCharacteristic
AVColorTransferCharacteristic
Color Transfer Characteristic.
Definition: pixfmt.h:527
AVCodecContext::av_class
const AVClass * av_class
information on struct for av_log
Definition: avcodec.h:403
AVCodecParserContext::pict_type
int pict_type
Definition: avcodec.h:2808
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1007
AVCodecContext::rc_min_rate
int64_t rc_min_rate
minimum bitrate
Definition: avcodec.h:1230
AVCodecParserContext::output_picture_number
int output_picture_number
Picture number incremented in presentation or output order.
Definition: avcodec.h:2934
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:53
sub
static float sub(float src0, float src1)
Definition: dnn_backend_native_layer_mathbinary.c:31
AVHWAccel::type
enum AVMediaType type
Type of codec implemented by the hardware accelerator.
Definition: avcodec.h:2083
AV_PICTURE_STRUCTURE_UNKNOWN
@ AV_PICTURE_STRUCTURE_UNKNOWN
Definition: avcodec.h:2794
AVHWAccel::caps_internal
int caps_internal
Internal hwaccel capabilities.
Definition: avcodec.h:2207
avcodec_parameters_from_context
int avcodec_parameters_from_context(AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: codec_par.c:99
AVCodecParserContext::duration
int duration
Duration of the current frame.
Definition: avcodec.h:2914
AVCodecContext::err_recognition
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1351
avcodec_string
void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
Definition: avcodec.c:515
rational.h
AVCodecContext::coded_side_data
AVPacketSideData * coded_side_data
Additional data associated with the entire coded stream.
Definition: avcodec.h:1858
AVSubtitleRect
Definition: avcodec.h:2280
AVSubtitle::num_rects
unsigned num_rects
Definition: avcodec.h:2312
av_parser_iterate
const AVCodecParser * av_parser_iterate(void **opaque)
Iterate over all registered codec parsers.
Definition: parsers.c:84
AVCodecContext::intra_matrix
uint16_t * intra_matrix
custom intra quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:883
AVCodecContext::mv0_threshold
int mv0_threshold
Note: Value depends upon the compare function used for fullpel ME.
Definition: avcodec.h:954
AVCodecContext::lumi_masking
float lumi_masking
luminance masking (0-> disabled)
Definition: avcodec.h:717
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
AVCodecContext::color_trc
enum AVColorTransferCharacteristic color_trc
Color Transfer Characteristic.
Definition: avcodec.h:968
AVPacketSideData
Definition: packet.h:315
AVCodecParserContext::pts_dts_delta
int pts_dts_delta
Presentation delay of current frame in units of AVCodecContext.time_base.
Definition: avcodec.h:2890
AVCodecContext::slice_offset
int * slice_offset
slice offsets in the frame in bytes
Definition: avcodec.h:759
avcodec_decode_subtitle2
int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub, int *got_sub_ptr, AVPacket *avpkt)
Decode a subtitle message.
Definition: decode.c:863
AVCodecContext::field_order
enum AVFieldOrder field_order
Field order.
Definition: avcodec.h:1004
AVHWAccel::capabilities
int capabilities
Hardware accelerated codec capabilities.
Definition: avcodec.h:2103
version_major.h
AVCodecContext::b_quant_offset
float b_quant_offset
qscale offset between IP and B-frames
Definition: avcodec.h:686
AVCodecParserContext::height
int height
Definition: avcodec.h:2940
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:342
RcOverride::qscale
int qscale
Definition: avcodec.h:199
AVHWAccel::init
int(* init)(AVCodecContext *avctx)
Initialize the hwaccel private data.
Definition: avcodec.h:2188
AVCodecContext::subtitle_header
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:1708
AVSubtitleRect::linesize
int linesize[4]
Definition: avcodec.h:2292
AVCodecParserContext::cur_frame_start_index
int cur_frame_start_index
Definition: avcodec.h:2828
AVCodecContext::me_pre_cmp
int me_pre_cmp
motion estimation prepass comparison function
Definition: avcodec.h:831
AVDictionary
Definition: dict.c:31
AVColorPrimaries
AVColorPrimaries
Chromaticity coordinates of the source primaries.
Definition: pixfmt.h:502
avcodec_default_get_format
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: decode.c:935
avcodec_find_best_pix_fmt_of_list
enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list, enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr)
Find the best pixel format to convert to given a certain source pixel format.
Definition: imgconvert.c:31
AVCodecContext::mb_decision
int mb_decision
macroblock decision mode
Definition: avcodec.h:871
avcodec_is_open
int avcodec_is_open(AVCodecContext *s)
Definition: avcodec.c:714
AVCodecContext::qmax
int qmax
maximum quantizer
Definition: avcodec.h:1194
AVCodecParserContext::coded_width
int coded_width
Dimensions of the coded video.
Definition: avcodec.h:2945
AVCodecContext::delay
int delay
Codec delay.
Definition: avcodec.h:554
AVCodecContext::me_subpel_quality
int me_subpel_quality
subpel ME quality
Definition: avcodec.h:845
AVCodecContext::mb_cmp
int mb_cmp
macroblock comparison function (not supported yet)
Definition: avcodec.h:787
AVCodecContext::slice_count
int slice_count
slice count
Definition: avcodec.h:752
AVPictureStructure
AVPictureStructure
Definition: avcodec.h:2793
avcodec_pix_fmt_to_codec_tag
unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt)
Return a value representing the fourCC code associated to the pixel format pix_fmt,...
Definition: raw.c:306
SUBTITLE_ASS
@ SUBTITLE_ASS
Formatted text, the ass field must be set by the decoder and is authoritative.
Definition: avcodec.h:2275
AVCodecParserContext::parser
const struct AVCodecParser * parser
Definition: avcodec.h:2802
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:1735
AVCodecContext::skip_top
int skip_top
Number of macroblock rows at the top which are skipped.
Definition: avcodec.h:906
AVCodecParserContext::offset
int64_t offset
byte offset from starting packet start
Definition: avcodec.h:2840
AVHWAccel
Definition: avcodec.h:2070
AVCodecParserContext::key_frame
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:2849
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:362
AVCodecContext::skip_idct
enum AVDiscard skip_idct
Skip IDCT/dequantization for selected frames.
Definition: avcodec.h:1691
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:703
AVCodecContext::nsse_weight
int nsse_weight
noise vs.
Definition: avcodec.h:1543
AVCodecContext::codec
const struct AVCodec * codec
Definition: avcodec.h:407
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:2059
AVCodecContext::skip_frame
enum AVDiscard skip_frame
Skip decoding for selected frames.
Definition: avcodec.h:1698
AVCodecContext::thread_count
int thread_count
thread count is used to decide how many independent tasks should be passed to execute()
Definition: avcodec.h:1466
samplefmt.h
AVSubtitleRect::x
int x
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2281
AVCodecContext::initial_padding
int initial_padding
Audio only.
Definition: avcodec.h:1726
AVCodecContext::refs
int refs
number of reference frames
Definition: avcodec.h:947
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:478
AVCodecContext::bit_rate_tolerance
int bit_rate_tolerance
number of bits the bitstream is allowed to diverge from the reference.
Definition: avcodec.h:456
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:1407
av_parser_init
AVCodecParserContext * av_parser_init(int codec_id)
Definition: parser.c:32
pts
static int64_t pts
Definition: transcode_aac.c:654
AVCodecContext::coded_height
int coded_height
Definition: avcodec.h:586
AVCodecContext::max_samples
int64_t max_samples
The number of samples per frame to maximally accept.
Definition: avcodec.h:1999
codec.h
AVCodecParserContext::dts
int64_t dts
Definition: avcodec.h:2820
AVSubtitleRect::ass
char * ass
0 terminated ASS/SSA compatible event line.
Definition: avcodec.h:2303
AVHWAccel::priv_data_size
int priv_data_size
Size of the private data to allocate in AVCodecInternal.hwaccel_priv_data.
Definition: avcodec.h:2202
avsubtitle_free
void avsubtitle_free(AVSubtitle *sub)
Free all allocated data in the given subtitle struct.
Definition: avcodec.c:412
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:1176
AV_PICTURE_STRUCTURE_FRAME
@ AV_PICTURE_STRUCTURE_FRAME
Definition: avcodec.h:2797
RcOverride::quality_factor
float quality_factor
Definition: avcodec.h:200
AVCodecContext::color_primaries
enum AVColorPrimaries color_primaries
Chromaticity coordinates of the source primaries.
Definition: avcodec.h:961
AVCodecParserContext::cur_frame_end
int64_t cur_frame_end[AV_PARSER_PTS_NB]
Definition: avcodec.h:2841
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:1763
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:1251
codec_id.h
AVHWAccel::alloc_frame
int(* alloc_frame)(AVCodecContext *avctx, AVFrame *frame)
Allocate a custom buffer.
Definition: avcodec.h:2116
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:500
AVCodecContext::has_b_frames
int has_b_frames
Size of the frame reordering buffer in the decoder.
Definition: avcodec.h:694
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:149
width
#define width
AVCodecDescriptor
This struct describes the properties of a single codec described by an AVCodecID.
Definition: codec_desc.h:38
s
#define s(width, name)
Definition: cbs_vp9.c:256
AVCodecContext::stats_in
char * stats_in
pass2 encoding statistics input buffer Concatenated stuff from stats_out of pass1 should be placed he...
Definition: avcodec.h:1273
AVCodecContext::global_quality
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:464
AVCodecParserContext::fetch_timestamp
int fetch_timestamp
Definition: avcodec.h:2825
AVHWAccel::uninit
int(* uninit)(AVCodecContext *avctx)
Uninitialize the hwaccel private data.
Definition: avcodec.h:2196
RcOverride
Definition: avcodec.h:196
AVCodecParserContext::last_pts
int64_t last_pts
Definition: avcodec.h:2823
AVSubtitleRect::y
int y
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2282
AVCodecContext::ticks_per_frame
int ticks_per_frame
For some codecs, the time base is closer to the field rate than the frame rate.
Definition: avcodec.h:530
AVCodecContext::error_concealment
int error_concealment
error concealment flags
Definition: avcodec.h:1317
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:719
AVSubtitleType
AVSubtitleType
Definition: avcodec.h:2260
AVCodecContext::thread_type
int thread_type
Which multithreading methods to use.
Definition: avcodec.h:1476
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1451
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:368
RcOverride::start_frame
int start_frame
Definition: avcodec.h:197
channels
channels
Definition: aptx.h:31
AVCodecParserContext::format
int format
The format of the coded data, corresponds to enum AVPixelFormat for video and for enum AVSampleFormat...
Definition: avcodec.h:2956
AVSubtitle::pts
int64_t pts
Same as packet pts, in AV_TIME_BASE.
Definition: avcodec.h:2314
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demuxing_decoding.c:41
avcodec_align_dimensions2
void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height, int linesize_align[AV_NUM_DATA_POINTERS])
Modify width and height values so that they will result in a memory buffer that is acceptable for the...
Definition: utils.c:141
AVCodecContext::max_pixels
int64_t max_pixels
The number of pixels per image to maximally accept.
Definition: avcodec.h:1911
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:388
AVHWAccel::decode_params
int(* decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size)
Callback for parameter data (SPS/PPS/VPS etc).
Definition: avcodec.h:2146
AVCodecContext::rc_max_rate
int64_t rc_max_rate
maximum bitrate
Definition: avcodec.h:1223
AVCodecContext::error
uint64_t error[AV_NUM_DATA_POINTERS]
error
Definition: avcodec.h:1400
AVSubtitleRect::text
char * text
0 terminated plain UTF-8 text
Definition: avcodec.h:2296
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:408
AVCodecContext::p_masking
float p_masking
p block masking (0-> disabled)
Definition: avcodec.h:738
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:2876
AVCodecParserContext::repeat_pict
int repeat_pict
This field is used for proper frame duration computation in lavf.
Definition: avcodec.h:2818
AV_PICTURE_STRUCTURE_BOTTOM_FIELD
@ AV_PICTURE_STRUCTURE_BOTTOM_FIELD
Definition: avcodec.h:2796
AVCodecContext::rc_buffer_size
int rc_buffer_size
decoder bitstream buffer size
Definition: avcodec.h:1208
AVCodecContext::sub_charenc
char * sub_charenc
DTS of the last frame.
Definition: avcodec.h:1773
AVSubtitleRect::w
int w
width of pict, undefined when pict is not set
Definition: avcodec.h:2283
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
avcodec_get_class
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:183
AVCodecContext::apply_cropping
int apply_cropping
Video decoding only.
Definition: avcodec.h:1969
AVCodecContext::color_range
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:982
AVCodecContext::slice_flags
int slice_flags
slice flags
Definition: avcodec.h:861
AVCodecParser::parser_close
void(* parser_close)(AVCodecParserContext *s)
Definition: avcodec.h:2969
avcodec_free_context
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
Definition: options.c:164
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVCodecContext::nb_coded_side_data
int nb_coded_side_data
Definition: avcodec.h:1859
AVCodecContext::qblur
float qblur
amount of qscale smoothing over time (0.0-1.0)
Definition: avcodec.h:1180
AV_PICTURE_STRUCTURE_TOP_FIELD
@ AV_PICTURE_STRUCTURE_TOP_FIELD
Definition: avcodec.h:2795
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:448
AVCodecParser::split
int(* split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
Definition: avcodec.h:2970
AVHWAccel::end_frame
int(* end_frame)(AVCodecContext *avctx)
Called at the end of each frame or field picture.
Definition: avcodec.h:2170
AVCodecContext::subtitle_header_size
int subtitle_header_size
Definition: avcodec.h:1709
AVSubtitleRect::data
uint8_t * data[4]
data+linesize for the bitmap of this subtitle.
Definition: avcodec.h:2291
AVCodecContext::trailing_padding
int trailing_padding
Audio only.
Definition: avcodec.h:1903
AVCodecContext::ildct_cmp
int ildct_cmp
interlaced DCT comparison function
Definition: avcodec.h:793
avcodec_license
const char * avcodec_license(void)
Return the libavcodec license.
Definition: version.c:46
AVCodecContext::thread_safe_callbacks
attribute_deprecated int thread_safe_callbacks
Set by the client if its custom get_buffer() callback can be called synchronously from another thread...
Definition: avcodec.h:1505
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:1244
avcodec_open2
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:115
AVCodecParserContext::flags
int flags
Definition: avcodec.h:2833
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:775
AVCodecParserContext::picture_structure
enum AVPictureStructure picture_structure
Indicate whether a picture is coded as a frame, top field or bottom field.
Definition: avcodec.h:2926
AVCodecContext::trellis
int trellis
trellis RD quantization
Definition: avcodec.h:1258
AVCodecContext::level
int level
level
Definition: avcodec.h:1676
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVAudioServiceType
AVAudioServiceType
Definition: defs.h:79
avcodec_get_subtitle_rect_class
const AVClass * avcodec_get_subtitle_rect_class(void)
Get the AVClass for AVSubtitleRect.
Definition: options.c:241
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:49
AVCodecContext::temporal_cplx_masking
float temporal_cplx_masking
temporary complexity masking (0-> disabled)
Definition: avcodec.h:724
AVCodecContext::qcompress
float qcompress
amount of qscale change between easy & hard scenes (0.0-1.0)
Definition: avcodec.h:1179
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:521
AVCodecContext::lowres
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:1458
options
const OptionDef options[]
AVCodecContext::stats_out
char * stats_out
pass1 encoding statistics output buffer
Definition: avcodec.h:1265
AVCodecContext::rc_override
RcOverride * rc_override
Definition: avcodec.h:1216
AVCodecContext::flags2
int flags2
AV_CODEC_FLAG2_*.
Definition: avcodec.h:485
AVMediaType
AVMediaType
Definition: avutil.h:199
AVCodecParserContext::frame_offset
int64_t frame_offset
Definition: avcodec.h:2803
AVCodecContext::gop_size
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:593
AVCodecParser::codec_ids
int codec_ids[7]
Definition: avcodec.h:2960
AVCodecContext::extra_hw_frames
int extra_hw_frames
Definition: avcodec.h:1983
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:293
AVCodecParserContext::next_frame_offset
int64_t next_frame_offset
Definition: avcodec.h:2806
AVCodecParserContext::cur_frame_offset
int64_t cur_frame_offset[AV_PARSER_PTS_NB]
Definition: avcodec.h:2829
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1023
AVCodecContext::pkt_timebase
AVRational pkt_timebase
Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
Definition: avcodec.h:1749
size
int size
Definition: twinvq_data.h:10344
AVCodecParserContext::width
int width
Dimensions of the decoded video intended for presentation.
Definition: avcodec.h:2939
AV_NUM_DATA_POINTERS
#define AV_NUM_DATA_POINTERS
Definition: frame.h:326
avcodec_get_frame_class
const attribute_deprecated AVClass * avcodec_get_frame_class(void)
Definition: options.c:214
AVCodecContext::me_range
int me_range
maximum motion estimation search range in subpel units If 0 then no limit.
Definition: avcodec.h:854
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:2965
AVCodecContext::skip_alpha
int skip_alpha
Skip processing alpha if supported by codec.
Definition: avcodec.h:1799
AVCodecContext::chroma_intra_matrix
uint16_t * chroma_intra_matrix
custom intra quantization matrix
Definition: avcodec.h:1824
AVCodecContext::skip_bottom
int skip_bottom
Number of macroblock rows at the bottom which are skipped.
Definition: avcodec.h:913
AVCodecContext::last_predictor_count
int last_predictor_count
amount of previous MV predictors (2a+1 x 2a+1 square)
Definition: avcodec.h:824
AVSubtitle::end_display_time
uint32_t end_display_time
Definition: avcodec.h:2311
frame.h
AVSubtitleRect::type
enum AVSubtitleType type
Definition: avcodec.h:2294
SUBTITLE_TEXT
@ SUBTITLE_TEXT
Plain text, the text field must be set by the decoder and is authoritative.
Definition: avcodec.h:2269
buffer.h
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
SUBTITLE_NONE
@ SUBTITLE_NONE
Definition: avcodec.h:2261
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:781
AVCodecContext::pts_correction_num_faulty_dts
int64_t pts_correction_num_faulty_dts
Number of incorrect PTS values so far.
Definition: avcodec.h:1764
height
#define height
AVCodecContext::pts_correction_last_pts
int64_t pts_correction_last_pts
Number of incorrect DTS values so far.
Definition: avcodec.h:1765
avcodec_default_execute
int avcodec_default_execute(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
Definition: avcodec.c:45
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
AVCodecContext::request_sample_fmt
enum AVSampleFormat request_sample_fmt
desired sample format
Definition: avcodec.h:1094
attributes.h
AVCodecInternal
Definition: internal.h:52
AVCodecContext::skip_loop_filter
enum AVDiscard skip_loop_filter
Skip loop filtering for selected frames.
Definition: avcodec.h:1684
SUBTITLE_BITMAP
@ SUBTITLE_BITMAP
A bitmap, pict will be set.
Definition: avcodec.h:2263
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:679
AVCodecParserContext::cur_frame_pts
int64_t cur_frame_pts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2830
AVChromaLocation
AVChromaLocation
Location of chroma samples.
Definition: pixfmt.h:649
AVCodecParserContext::cur_frame_pos
int64_t cur_frame_pos[AV_PARSER_PTS_NB]
Position of the packet in file.
Definition: avcodec.h:2897
AVHWAccel::name
const char * name
Name of the hardware accelerated codec.
Definition: avcodec.h:2076
AVSubtitleRect::flags
int flags
Definition: avcodec.h:2305
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1444
avcodec_default_get_buffer2
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags)
The default callback for AVCodecContext.get_buffer2().
Definition: get_buffer.c:282
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:637
AVCodecParserContext::pos
int64_t pos
Byte position of currently parsed frame in stream.
Definition: avcodec.h:2902
AVSubtitle::format
uint16_t format
Definition: avcodec.h:2309
log.h
RcOverride::end_frame
int end_frame
Definition: avcodec.h:198
AVCodecContext::properties
unsigned properties
Properties of the stream that gets decoded.
Definition: avcodec.h:1847
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:499
AVSubtitleRect::nb_colors
int nb_colors
number of colors in pict, undefined when pict is not set
Definition: avcodec.h:2285
AVHWAccel::decode_slice
int(* decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size)
Callback for each slice.
Definition: avcodec.h:2159
packet.h
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: codec_par.c:182
AVCodecContext::intra_dc_precision
int intra_dc_precision
precision of the intra DC coefficient - 8
Definition: avcodec.h:899
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:556
AVCodecContext::cutoff
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1059
AVCodecContext::hwaccel_flags
int hwaccel_flags
Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated decoding (if active).
Definition: avcodec.h:1942
AVCodecParserContext::cur_offset
int64_t cur_offset
Definition: avcodec.h:2804
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
av_fast_padded_malloc
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_malloc but the buffer has additional AV_INPUT_BUFFER_PADDING_SIZE at the end w...
Definition: utils.c:49
AVCodecParser::parser_init
int(* parser_init)(AVCodecParserContext *s)
Definition: avcodec.h:2962
AVCodecContext::pts_correction_last_dts
int64_t pts_correction_last_dts
PTS of the last frame.
Definition: avcodec.h:1766
AVCodecContext::dia_size
int dia_size
ME diamond size & shape.
Definition: avcodec.h:817
AVCodecContext::dump_separator
uint8_t * dump_separator
dump format separator.
Definition: avcodec.h:1832
AVCodecContext::mb_lmin
int mb_lmin
minimum MB Lagrange multiplier
Definition: avcodec.h:920
av_get_audio_frame_duration
int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
Return audio frame duration.
Definition: utils.c:808
AVCodecContext::idct_algo
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:1420
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:1933
AVCodecContext::chroma_sample_location
enum AVChromaLocation chroma_sample_location
This defines the location of chroma samples.
Definition: avcodec.h:989
AVCodecContext::height
int height
Definition: avcodec.h:571
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:445
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:608
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:1883
AVCodecParserContext
Definition: avcodec.h:2800
AVCodecContext::sub_charenc_mode
int sub_charenc_mode
Subtitles character encoding mode.
Definition: avcodec.h:1781
avcodec_get_hw_frames_parameters
int avcodec_get_hw_frames_parameters(AVCodecContext *avctx, AVBufferRef *device_ref, enum AVPixelFormat hw_pix_fmt, AVBufferRef **out_frames_ref)
Create and return a AVHWFramesContext with values adequate for hardware decoding.
Definition: decode.c:1049
ret
ret
Definition: filter_design.txt:187
AVSubtitleRect::h
int h
height of pict, undefined when pict is not set
Definition: avcodec.h:2284
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:1052
pixfmt.h
avcodec_flush_buffers
void avcodec_flush_buffers(AVCodecContext *avctx)
Reset the internal codec state / flush internal buffers.
Definition: avcodec.c:369
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AVCodecContext::sub_text_format
attribute_deprecated int sub_text_format
Definition: avcodec.h:1890
AVCodecParserContext::coded_height
int coded_height
Definition: avcodec.h:2946
AVCodecContext::strict_std_compliance
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1310
AVCodecContext::opaque
void * opaque
Private data of the user, can be used to carry app specific stuff.
Definition: avcodec.h:440
pos
unsigned int pos
Definition: spdifenc.c:412
AVCodecParser::priv_data_size
int priv_data_size
Definition: avcodec.h:2961
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:633
AVCodecContext::max_qdiff
int max_qdiff
maximum quantizer difference between frames
Definition: avcodec.h:1201
AVCodecContext::dark_masking
float dark_masking
darkness masking (0-> disabled)
Definition: avcodec.h:745
AVCodecContext
main external API structure.
Definition: avcodec.h:398
AVCodecContext::active_thread_type
int active_thread_type
Which multithreading methods are in use by the codec.
Definition: avcodec.h:1485
AVCodecContext::codec_descriptor
const AVCodecDescriptor * codec_descriptor
AVCodecDescriptor.
Definition: avcodec.h:1756
c2
static const uint64_t c2
Definition: murmur3.c:52
AVCodecParserContext::field_order
enum AVFieldOrder field_order
Definition: avcodec.h:2916
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:1517
AVCodecContext::qmin
int qmin
minimum quantizer
Definition: avcodec.h:1187
AVHWAccel::frame_priv_data_size
int frame_priv_data_size
Size of per-frame hardware accelerator private data.
Definition: avcodec.h:2179
AVCodecContext::bidir_refine
int bidir_refine
Definition: avcodec.h:933
AVCodecContext::profile
int profile
profile
Definition: avcodec.h:1550
defs.h
av_fast_padded_mallocz
void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_padded_malloc except that buffer will always be 0-initialized after call.
Definition: utils.c:62
AVCodecContext::get_encode_buffer
int(* get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags)
This callback is called at the beginning of each packet to get a data buffer for it.
Definition: avcodec.h:2051
AVCodecContext::spatial_cplx_masking
float spatial_cplx_masking
spatial complexity masking (0-> disabled)
Definition: avcodec.h:731
AVCodecContext::i_quant_offset
float i_quant_offset
qscale offset between P and I-frames
Definition: avcodec.h:710
AVCodecContext::discard_damaged_percentage
int discard_damaged_percentage
The percentage of damaged samples to discard a frame.
Definition: avcodec.h:1991
AVCodecContext::mb_lmax
int mb_lmax
maximum MB Lagrange multiplier
Definition: avcodec.h:927
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:2009
AVCodecContext::pre_dia_size
int pre_dia_size
ME prepass diamond size & shape.
Definition: avcodec.h:838
AVCodecContext::debug
int debug
debug
Definition: avcodec.h:1327
AVHWAccel::start_frame
int(* start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size)
Called at the beginning of each frame or field picture.
Definition: avcodec.h:2132
AVCodecContext::coded_width
int coded_width
Bitstream width / height, may be different from width/height e.g.
Definition: avcodec.h:586
AVCodecContext::codec_type
enum AVMediaType codec_type
Definition: avcodec.h:406
AVCodecContext::seek_preroll
int seek_preroll
Number of samples to skip after a discontinuity.
Definition: avcodec.h:1806
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:670
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
AVCodecContext::frame_number
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:1046
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:1237
AVCodecContext::codec_tag
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:423
codec_par.h
AVFieldOrder
AVFieldOrder
Definition: codec_par.h:37
AV_PARSER_PTS_NB
#define AV_PARSER_PTS_NB
Definition: avcodec.h:2827
AVCodecContext::slices
int slices
Number of slices.
Definition: avcodec.h:998
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:425
avcodec_default_get_encode_buffer
int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags)
The default callback for AVCodecContext.get_encode_buffer().
Definition: encode.c:57
AVCodecParserContext::last_pos
int64_t last_pos
Previous frame byte position.
Definition: avcodec.h:2907
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:892
AVHWAccel::frame_params
int(* frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx)
Fill the given hw_frames context with current codec parameters.
Definition: avcodec.h:2217
AVCodecParser
Definition: avcodec.h:2959
AVCodecContext::rc_override_count
int rc_override_count
ratecontrol override, see RcOverride
Definition: avcodec.h:1215
AVCodecContext::reordered_opaque
int64_t reordered_opaque
opaque 64-bit number (generally a PTS) that will be reordered and output in AVFrame....
Definition: avcodec.h:1362
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:571
AVCodecContext::debug_mv
attribute_deprecated int debug_mv
Definition: avcodec.h:1813
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParserContext::priv_data
void * priv_data
Definition: avcodec.h:2801
AVCodecContext::sw_pix_fmt
enum AVPixelFormat sw_pix_fmt
Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1742
AVCodecParserContext::cur_frame_dts
int64_t cur_frame_dts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2831
AVCodecContext::codec_whitelist
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avcodec.h:1840
AVDiscard
AVDiscard
Definition: defs.h:67
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:595
AVCodecParserContext::last_dts
int64_t last_dts
Definition: avcodec.h:2824
codec_desc.h
int
int
Definition: ffmpeg_filter.c:156
AVCodecContext::execute2
int(* execute2)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count)
The codec may call this to execute several independent things.
Definition: avcodec.h:1536
AVHWAccel::pix_fmt
enum AVPixelFormat pix_fmt
Supported pixel format.
Definition: avcodec.h:2097
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:768
AVSubtitle::start_display_time
uint32_t start_display_time
Definition: avcodec.h:2310
AVCodecContext::compression_level
int compression_level
Definition: avcodec.h:470
av_parser_close
void av_parser_close(AVCodecParserContext *s)
Definition: parser.c:189
AVHWAccel::id
enum AVCodecID id
Codec implemented by the hardware accelerator.
Definition: avcodec.h:2090