FFmpeg
avcodec.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
23 
24 /**
25  * @file
26  * @ingroup libavc
27  * Libavcodec external API header
28  */
29 
30 #include "libavutil/samplefmt.h"
31 #include "libavutil/attributes.h"
32 #include "libavutil/avutil.h"
33 #include "libavutil/buffer.h"
34 #include "libavutil/dict.h"
35 #include "libavutil/frame.h"
36 #include "libavutil/log.h"
37 #include "libavutil/pixfmt.h"
38 #include "libavutil/rational.h"
39 
40 #include "codec.h"
41 #include "codec_desc.h"
42 #include "codec_par.h"
43 #include "codec_id.h"
44 #include "defs.h"
45 #include "packet.h"
46 #include "version.h"
47 
48 /**
49  * @defgroup libavc libavcodec
50  * Encoding/Decoding Library
51  *
52  * @{
53  *
54  * @defgroup lavc_decoding Decoding
55  * @{
56  * @}
57  *
58  * @defgroup lavc_encoding Encoding
59  * @{
60  * @}
61  *
62  * @defgroup lavc_codec Codecs
63  * @{
64  * @defgroup lavc_codec_native Native Codecs
65  * @{
66  * @}
67  * @defgroup lavc_codec_wrappers External library wrappers
68  * @{
69  * @}
70  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
71  * @{
72  * @}
73  * @}
74  * @defgroup lavc_internal Internal
75  * @{
76  * @}
77  * @}
78  */
79 
80 /**
81  * @ingroup libavc
82  * @defgroup lavc_encdec send/receive encoding and decoding API overview
83  * @{
84  *
85  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
86  * avcodec_receive_packet() functions provide an encode/decode API, which
87  * decouples input and output.
88  *
89  * The API is very similar for encoding/decoding and audio/video, and works as
90  * follows:
91  * - Set up and open the AVCodecContext as usual.
92  * - Send valid input:
93  * - For decoding, call avcodec_send_packet() to give the decoder raw
94  * compressed data in an AVPacket.
95  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
96  * containing uncompressed audio or video.
97  *
98  * In both cases, it is recommended that AVPackets and AVFrames are
99  * refcounted, or libavcodec might have to copy the input data. (libavformat
100  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
101  * refcounted AVFrames.)
102  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
103  * functions and process their output:
104  * - For decoding, call avcodec_receive_frame(). On success, it will return
105  * an AVFrame containing uncompressed audio or video data.
106  * - For encoding, call avcodec_receive_packet(). On success, it will return
107  * an AVPacket with a compressed frame.
108  *
109  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
110  * AVERROR(EAGAIN) return value means that new input data is required to
111  * return new output. In this case, continue with sending input. For each
112  * input frame/packet, the codec will typically return 1 output frame/packet,
113  * but it can also be 0 or more than 1.
114  *
115  * At the beginning of decoding or encoding, the codec might accept multiple
116  * input frames/packets without returning a frame, until its internal buffers
117  * are filled. This situation is handled transparently if you follow the steps
118  * outlined above.
119  *
120  * In theory, sending input can result in EAGAIN - this should happen only if
121  * not all output was received. You can use this to structure alternative decode
122  * or encode loops other than the one suggested above. For example, you could
123  * try sending new input on each iteration, and try to receive output if that
124  * returns EAGAIN.
125  *
126  * End of stream situations. These require "flushing" (aka draining) the codec,
127  * as the codec might buffer multiple frames or packets internally for
128  * performance or out of necessity (consider B-frames).
129  * This is handled as follows:
130  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
131  * or avcodec_send_frame() (encoding) functions. This will enter draining
132  * mode.
133  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
134  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
135  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
136  * - Before decoding can be resumed again, the codec has to be reset with
137  * avcodec_flush_buffers().
138  *
139  * Using the API as outlined above is highly recommended. But it is also
140  * possible to call functions outside of this rigid schema. For example, you can
141  * call avcodec_send_packet() repeatedly without calling
142  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
143  * until the codec's internal buffer has been filled up (which is typically of
144  * size 1 per output frame, after initial input), and then reject input with
145  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
146  * read at least some output.
147  *
148  * Not all codecs will follow a rigid and predictable dataflow; the only
149  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
150  * one end implies that a receive/send call on the other end will succeed, or
151  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
152  * permit unlimited buffering of input or output.
153  *
154  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
155  * would be an invalid state, which could put the codec user into an endless
156  * loop. The API has no concept of time either: it cannot happen that trying to
157  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
158  * later accepts the packet (with no other receive/flush API calls involved).
159  * The API is a strict state machine, and the passage of time is not supposed
160  * to influence it. Some timing-dependent behavior might still be deemed
161  * acceptable in certain cases. But it must never result in both send/receive
162  * returning EAGAIN at the same time at any point. It must also absolutely be
163  * avoided that the current state is "unstable" and can "flip-flop" between
164  * the send/receive APIs allowing progress. For example, it's not allowed that
165  * the codec randomly decides that it actually wants to consume a packet now
166  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
167  * avcodec_send_packet() call.
168  * @}
169  */
170 
171 /**
172  * @defgroup lavc_core Core functions/structures.
173  * @ingroup libavc
174  *
175  * Basic definitions, functions for querying libavcodec capabilities,
176  * allocating core structures, etc.
177  * @{
178  */
179 
180 /**
181  * @ingroup lavc_encoding
182  * minimum encoding buffer size
183  * Used to avoid some checks during header writing.
184  */
185 #define AV_INPUT_BUFFER_MIN_SIZE 16384
186 
187 /**
188  * @ingroup lavc_encoding
189  */
190 typedef struct RcOverride{
193  int qscale; // If this is 0 then quality_factor will be used instead.
195 } RcOverride;
196 
197 /* encoding support
198  These flags can be passed in AVCodecContext.flags before initialization.
199  Note: Not everything is supported yet.
200 */
201 
202 /**
203  * Allow decoders to produce frames with data planes that are not aligned
204  * to CPU requirements (e.g. due to cropping).
205  */
206 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
207 /**
208  * Use fixed qscale.
209  */
210 #define AV_CODEC_FLAG_QSCALE (1 << 1)
211 /**
212  * 4 MV per MB allowed / advanced prediction for H.263.
213  */
214 #define AV_CODEC_FLAG_4MV (1 << 2)
215 /**
216  * Output even those frames that might be corrupted.
217  */
218 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
219 /**
220  * Use qpel MC.
221  */
222 #define AV_CODEC_FLAG_QPEL (1 << 4)
223 /**
224  * Don't output frames whose parameters differ from first
225  * decoded frame in stream.
226  */
227 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
228 /**
229  * Use internal 2pass ratecontrol in first pass mode.
230  */
231 #define AV_CODEC_FLAG_PASS1 (1 << 9)
232 /**
233  * Use internal 2pass ratecontrol in second pass mode.
234  */
235 #define AV_CODEC_FLAG_PASS2 (1 << 10)
236 /**
237  * loop filter.
238  */
239 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
240 /**
241  * Only decode/encode grayscale.
242  */
243 #define AV_CODEC_FLAG_GRAY (1 << 13)
244 /**
245  * error[?] variables will be set during encoding.
246  */
247 #define AV_CODEC_FLAG_PSNR (1 << 15)
248 /**
249  * Input bitstream might be truncated at a random location
250  * instead of only at frame boundaries.
251  */
252 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
253 /**
254  * Use interlaced DCT.
255  */
256 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
257 /**
258  * Force low delay.
259  */
260 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
261 /**
262  * Place global headers in extradata instead of every keyframe.
263  */
264 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
265 /**
266  * Use only bitexact stuff (except (I)DCT).
267  */
268 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
269 /* Fx : Flag for H.263+ extra options */
270 /**
271  * H.263 advanced intra coding / MPEG-4 AC prediction
272  */
273 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
274 /**
275  * interlaced motion estimation
276  */
277 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
278 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
279 
280 /**
281  * Allow non spec compliant speedup tricks.
282  */
283 #define AV_CODEC_FLAG2_FAST (1 << 0)
284 /**
285  * Skip bitstream encoding.
286  */
287 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
288 /**
289  * Place global headers at every keyframe instead of in extradata.
290  */
291 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
292 
293 /**
294  * timecode is in drop frame format. DEPRECATED!!!!
295  */
296 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
297 
298 /**
299  * Input bitstream might be truncated at a packet boundaries
300  * instead of only at frame boundaries.
301  */
302 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
303 /**
304  * Discard cropping information from SPS.
305  */
306 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
307 
308 /**
309  * Show all frames before the first keyframe
310  */
311 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
312 /**
313  * Export motion vectors through frame side data
314  */
315 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
316 /**
317  * Do not skip samples and export skip information as frame side data
318  */
319 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
320 /**
321  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
322  */
323 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
324 
325 /* Unsupported options :
326  * Syntax Arithmetic coding (SAC)
327  * Reference Picture Selection
328  * Independent Segment Decoding */
329 /* /Fx */
330 /* codec capabilities */
331 
332 /* Exported side data.
333  These flags can be passed in AVCodecContext.export_side_data before initialization.
334 */
335 /**
336  * Export motion vectors through frame side data
337  */
338 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
339 /**
340  * Export encoder Producer Reference Time through packet side data
341  */
342 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
343 /**
344  * Decoding only.
345  * Export the AVVideoEncParams structure through frame side data.
346  */
347 #define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
348 /**
349  * Decoding only.
350  * Do not apply film grain, export it instead.
351  */
352 #define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
353 
354 /**
355  * The decoder will keep a reference to the frame and may reuse it later.
356  */
357 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
358 
359 /**
360  * The encoder will keep a reference to the packet and may reuse it later.
361  */
362 #define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
363 
364 struct AVCodecInternal;
365 
366 /**
367  * main external API structure.
368  * New fields can be added to the end with minor version bumps.
369  * Removal, reordering and changes to existing fields require a major
370  * version bump.
371  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
372  * applications.
373  * The name string for AVOptions options matches the associated command line
374  * parameter name and can be found in libavcodec/options_table.h
375  * The AVOption/command line parameter names differ in some cases from the C
376  * structure field names for historic reasons or brevity.
377  * sizeof(AVCodecContext) must not be used outside libav*.
378  */
379 typedef struct AVCodecContext {
380  /**
381  * information on struct for av_log
382  * - set by avcodec_alloc_context3
383  */
386 
387  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
388  const struct AVCodec *codec;
389  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
390 
391  /**
392  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
393  * This is used to work around some encoder bugs.
394  * A demuxer should set this to what is stored in the field used to identify the codec.
395  * If there are multiple such fields in a container then the demuxer should choose the one
396  * which maximizes the information about the used codec.
397  * If the codec tag field in a container is larger than 32 bits then the demuxer should
398  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
399  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
400  * first.
401  * - encoding: Set by user, if not then the default based on codec_id will be used.
402  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
403  */
404  unsigned int codec_tag;
405 
406  void *priv_data;
407 
408  /**
409  * Private context used for internal data.
410  *
411  * Unlike priv_data, this is not codec-specific. It is used in general
412  * libavcodec functions.
413  */
414  struct AVCodecInternal *internal;
415 
416  /**
417  * Private data of the user, can be used to carry app specific stuff.
418  * - encoding: Set by user.
419  * - decoding: Set by user.
420  */
421  void *opaque;
422 
423  /**
424  * the average bitrate
425  * - encoding: Set by user; unused for constant quantizer encoding.
426  * - decoding: Set by user, may be overwritten by libavcodec
427  * if this info is available in the stream
428  */
429  int64_t bit_rate;
430 
431  /**
432  * number of bits the bitstream is allowed to diverge from the reference.
433  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
434  * - encoding: Set by user; unused for constant quantizer encoding.
435  * - decoding: unused
436  */
438 
439  /**
440  * Global quality for codecs which cannot change it per frame.
441  * This should be proportional to MPEG-1/2/4 qscale.
442  * - encoding: Set by user.
443  * - decoding: unused
444  */
446 
447  /**
448  * - encoding: Set by user.
449  * - decoding: unused
450  */
452 #define FF_COMPRESSION_DEFAULT -1
453 
454  /**
455  * AV_CODEC_FLAG_*.
456  * - encoding: Set by user.
457  * - decoding: Set by user.
458  */
459  int flags;
460 
461  /**
462  * AV_CODEC_FLAG2_*
463  * - encoding: Set by user.
464  * - decoding: Set by user.
465  */
466  int flags2;
467 
468  /**
469  * some codecs need / can use extradata like Huffman tables.
470  * MJPEG: Huffman tables
471  * rv10: additional flags
472  * MPEG-4: global headers (they can be in the bitstream or here)
473  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
474  * than extradata_size to avoid problems if it is read with the bitstream reader.
475  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
476  * Must be allocated with the av_malloc() family of functions.
477  * - encoding: Set/allocated/freed by libavcodec.
478  * - decoding: Set/allocated/freed by user.
479  */
480  uint8_t *extradata;
482 
483  /**
484  * This is the fundamental unit of time (in seconds) in terms
485  * of which frame timestamps are represented. For fixed-fps content,
486  * timebase should be 1/framerate and timestamp increments should be
487  * identically 1.
488  * This often, but not always is the inverse of the frame rate or field rate
489  * for video. 1/time_base is not the average frame rate if the frame rate is not
490  * constant.
491  *
492  * Like containers, elementary streams also can store timestamps, 1/time_base
493  * is the unit in which these timestamps are specified.
494  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
495  * vop_time_increment_resolution and fixed_vop_rate
496  * (fixed_vop_rate == 0 implies that it is different from the framerate)
497  *
498  * - encoding: MUST be set by user.
499  * - decoding: the use of this field for decoding is deprecated.
500  * Use framerate instead.
501  */
503 
504  /**
505  * For some codecs, the time base is closer to the field rate than the frame rate.
506  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
507  * if no telecine is used ...
508  *
509  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
510  */
512 
513  /**
514  * Codec delay.
515  *
516  * Encoding: Number of frames delay there will be from the encoder input to
517  * the decoder output. (we assume the decoder matches the spec)
518  * Decoding: Number of frames delay in addition to what a standard decoder
519  * as specified in the spec would produce.
520  *
521  * Video:
522  * Number of frames the decoded output will be delayed relative to the
523  * encoded input.
524  *
525  * Audio:
526  * For encoding, this field is unused (see initial_padding).
527  *
528  * For decoding, this is the number of samples the decoder needs to
529  * output before the decoder's output is valid. When seeking, you should
530  * start decoding this many samples prior to your desired seek point.
531  *
532  * - encoding: Set by libavcodec.
533  * - decoding: Set by libavcodec.
534  */
535  int delay;
536 
537 
538  /* video only */
539  /**
540  * picture width / height.
541  *
542  * @note Those fields may not match the values of the last
543  * AVFrame output by avcodec_receive_frame() due frame
544  * reordering.
545  *
546  * - encoding: MUST be set by user.
547  * - decoding: May be set by the user before opening the decoder if known e.g.
548  * from the container. Some decoders will require the dimensions
549  * to be set by the caller. During decoding, the decoder may
550  * overwrite those values as required while parsing the data.
551  */
552  int width, height;
553 
554  /**
555  * Bitstream width / height, may be different from width/height e.g. when
556  * the decoded frame is cropped before being output or lowres is enabled.
557  *
558  * @note Those field may not match the value of the last
559  * AVFrame output by avcodec_receive_frame() due frame
560  * reordering.
561  *
562  * - encoding: unused
563  * - decoding: May be set by the user before opening the decoder if known
564  * e.g. from the container. During decoding, the decoder may
565  * overwrite those values as required while parsing the data.
566  */
568 
569  /**
570  * the number of pictures in a group of pictures, or 0 for intra_only
571  * - encoding: Set by user.
572  * - decoding: unused
573  */
574  int gop_size;
575 
576  /**
577  * Pixel format, see AV_PIX_FMT_xxx.
578  * May be set by the demuxer if known from headers.
579  * May be overridden by the decoder if it knows better.
580  *
581  * @note This field may not match the value of the last
582  * AVFrame output by avcodec_receive_frame() due frame
583  * reordering.
584  *
585  * - encoding: Set by user.
586  * - decoding: Set by user if known, overridden by libavcodec while
587  * parsing the data.
588  */
590 
591  /**
592  * If non NULL, 'draw_horiz_band' is called by the libavcodec
593  * decoder to draw a horizontal band. It improves cache usage. Not
594  * all codecs can do that. You must check the codec capabilities
595  * beforehand.
596  * When multithreading is used, it may be called from multiple threads
597  * at the same time; threads might draw different parts of the same AVFrame,
598  * or multiple AVFrames, and there is no guarantee that slices will be drawn
599  * in order.
600  * The function is also used by hardware acceleration APIs.
601  * It is called at least once during frame decoding to pass
602  * the data needed for hardware render.
603  * In that mode instead of pixel data, AVFrame points to
604  * a structure specific to the acceleration API. The application
605  * reads the structure and can change some fields to indicate progress
606  * or mark state.
607  * - encoding: unused
608  * - decoding: Set by user.
609  * @param height the height of the slice
610  * @param y the y position of the slice
611  * @param type 1->top field, 2->bottom field, 3->frame
612  * @param offset offset into the AVFrame.data from which the slice should be read
613  */
615  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
616  int y, int type, int height);
617 
618  /**
619  * Callback to negotiate the pixel format. Decoding only, may be set by the
620  * caller before avcodec_open2().
621  *
622  * Called by some decoders to select the pixel format that will be used for
623  * the output frames. This is mainly used to set up hardware acceleration,
624  * then the provided format list contains the corresponding hwaccel pixel
625  * formats alongside the "software" one. The software pixel format may also
626  * be retrieved from \ref sw_pix_fmt.
627  *
628  * This callback will be called when the coded frame properties (such as
629  * resolution, pixel format, etc.) change and more than one output format is
630  * supported for those new properties. If a hardware pixel format is chosen
631  * and initialization for it fails, the callback may be called again
632  * immediately.
633  *
634  * This callback may be called from different threads if the decoder is
635  * multi-threaded, but not from more than one thread simultaneously.
636  *
637  * @param fmt list of formats which may be used in the current
638  * configuration, terminated by AV_PIX_FMT_NONE.
639  * @warning Behavior is undefined if the callback returns a value other
640  * than one of the formats in fmt or AV_PIX_FMT_NONE.
641  * @return the chosen format or AV_PIX_FMT_NONE
642  */
643  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
644 
645  /**
646  * maximum number of B-frames between non-B-frames
647  * Note: The output will be delayed by max_b_frames+1 relative to the input.
648  * - encoding: Set by user.
649  * - decoding: unused
650  */
652 
653  /**
654  * qscale factor between IP and B-frames
655  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
656  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
657  * - encoding: Set by user.
658  * - decoding: unused
659  */
661 
662  /**
663  * qscale offset between IP and B-frames
664  * - encoding: Set by user.
665  * - decoding: unused
666  */
668 
669  /**
670  * Size of the frame reordering buffer in the decoder.
671  * For MPEG-2 it is 1 IPB or 0 low delay IP.
672  * - encoding: Set by libavcodec.
673  * - decoding: Set by libavcodec.
674  */
676 
677  /**
678  * qscale factor between P- and I-frames
679  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
680  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
681  * - encoding: Set by user.
682  * - decoding: unused
683  */
685 
686  /**
687  * qscale offset between P and I-frames
688  * - encoding: Set by user.
689  * - decoding: unused
690  */
692 
693  /**
694  * luminance masking (0-> disabled)
695  * - encoding: Set by user.
696  * - decoding: unused
697  */
699 
700  /**
701  * temporary complexity masking (0-> disabled)
702  * - encoding: Set by user.
703  * - decoding: unused
704  */
706 
707  /**
708  * spatial complexity masking (0-> disabled)
709  * - encoding: Set by user.
710  * - decoding: unused
711  */
713 
714  /**
715  * p block masking (0-> disabled)
716  * - encoding: Set by user.
717  * - decoding: unused
718  */
719  float p_masking;
720 
721  /**
722  * darkness masking (0-> disabled)
723  * - encoding: Set by user.
724  * - decoding: unused
725  */
727 
728  /**
729  * slice count
730  * - encoding: Set by libavcodec.
731  * - decoding: Set by user (or 0).
732  */
734 
735  /**
736  * slice offsets in the frame in bytes
737  * - encoding: Set/allocated by libavcodec.
738  * - decoding: Set/allocated by user (or NULL).
739  */
741 
742  /**
743  * sample aspect ratio (0 if unknown)
744  * That is the width of a pixel divided by the height of the pixel.
745  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
746  * - encoding: Set by user.
747  * - decoding: Set by libavcodec.
748  */
750 
751  /**
752  * motion estimation comparison function
753  * - encoding: Set by user.
754  * - decoding: unused
755  */
756  int me_cmp;
757  /**
758  * subpixel motion estimation comparison function
759  * - encoding: Set by user.
760  * - decoding: unused
761  */
763  /**
764  * macroblock comparison function (not supported yet)
765  * - encoding: Set by user.
766  * - decoding: unused
767  */
768  int mb_cmp;
769  /**
770  * interlaced DCT comparison function
771  * - encoding: Set by user.
772  * - decoding: unused
773  */
775 #define FF_CMP_SAD 0
776 #define FF_CMP_SSE 1
777 #define FF_CMP_SATD 2
778 #define FF_CMP_DCT 3
779 #define FF_CMP_PSNR 4
780 #define FF_CMP_BIT 5
781 #define FF_CMP_RD 6
782 #define FF_CMP_ZERO 7
783 #define FF_CMP_VSAD 8
784 #define FF_CMP_VSSE 9
785 #define FF_CMP_NSSE 10
786 #define FF_CMP_W53 11
787 #define FF_CMP_W97 12
788 #define FF_CMP_DCTMAX 13
789 #define FF_CMP_DCT264 14
790 #define FF_CMP_MEDIAN_SAD 15
791 #define FF_CMP_CHROMA 256
792 
793  /**
794  * ME diamond size & shape
795  * - encoding: Set by user.
796  * - decoding: unused
797  */
798  int dia_size;
799 
800  /**
801  * amount of previous MV predictors (2a+1 x 2a+1 square)
802  * - encoding: Set by user.
803  * - decoding: unused
804  */
806 
807  /**
808  * motion estimation prepass comparison function
809  * - encoding: Set by user.
810  * - decoding: unused
811  */
813 
814  /**
815  * ME prepass diamond size & shape
816  * - encoding: Set by user.
817  * - decoding: unused
818  */
820 
821  /**
822  * subpel ME quality
823  * - encoding: Set by user.
824  * - decoding: unused
825  */
827 
828  /**
829  * maximum motion estimation search range in subpel units
830  * If 0 then no limit.
831  *
832  * - encoding: Set by user.
833  * - decoding: unused
834  */
835  int me_range;
836 
837  /**
838  * slice flags
839  * - encoding: unused
840  * - decoding: Set by user.
841  */
843 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
844 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
845 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
846 
847  /**
848  * macroblock decision mode
849  * - encoding: Set by user.
850  * - decoding: unused
851  */
853 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
854 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
855 #define FF_MB_DECISION_RD 2 ///< rate distortion
856 
857  /**
858  * custom intra quantization matrix
859  * Must be allocated with the av_malloc() family of functions, and will be freed in
860  * avcodec_free_context().
861  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
862  * - decoding: Set/allocated/freed by libavcodec.
863  */
864  uint16_t *intra_matrix;
865 
866  /**
867  * custom inter quantization matrix
868  * Must be allocated with the av_malloc() family of functions, and will be freed in
869  * avcodec_free_context().
870  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
871  * - decoding: Set/allocated/freed by libavcodec.
872  */
873  uint16_t *inter_matrix;
874 
875  /**
876  * precision of the intra DC coefficient - 8
877  * - encoding: Set by user.
878  * - decoding: Set by libavcodec
879  */
881 
882  /**
883  * Number of macroblock rows at the top which are skipped.
884  * - encoding: unused
885  * - decoding: Set by user.
886  */
887  int skip_top;
888 
889  /**
890  * Number of macroblock rows at the bottom which are skipped.
891  * - encoding: unused
892  * - decoding: Set by user.
893  */
895 
896  /**
897  * minimum MB Lagrange multiplier
898  * - encoding: Set by user.
899  * - decoding: unused
900  */
901  int mb_lmin;
902 
903  /**
904  * maximum MB Lagrange multiplier
905  * - encoding: Set by user.
906  * - decoding: unused
907  */
908  int mb_lmax;
909 
910  /**
911  * - encoding: Set by user.
912  * - decoding: unused
913  */
915 
916  /**
917  * minimum GOP size
918  * - encoding: Set by user.
919  * - decoding: unused
920  */
922 
923  /**
924  * number of reference frames
925  * - encoding: Set by user.
926  * - decoding: Set by lavc.
927  */
928  int refs;
929 
930  /**
931  * Note: Value depends upon the compare function used for fullpel ME.
932  * - encoding: Set by user.
933  * - decoding: unused
934  */
936 
937  /**
938  * Chromaticity coordinates of the source primaries.
939  * - encoding: Set by user
940  * - decoding: Set by libavcodec
941  */
943 
944  /**
945  * Color Transfer Characteristic.
946  * - encoding: Set by user
947  * - decoding: Set by libavcodec
948  */
950 
951  /**
952  * YUV colorspace type.
953  * - encoding: Set by user
954  * - decoding: Set by libavcodec
955  */
957 
958  /**
959  * MPEG vs JPEG YUV range.
960  * - encoding: Set by user
961  * - decoding: Set by libavcodec
962  */
964 
965  /**
966  * This defines the location of chroma samples.
967  * - encoding: Set by user
968  * - decoding: Set by libavcodec
969  */
971 
972  /**
973  * Number of slices.
974  * Indicates number of picture subdivisions. Used for parallelized
975  * decoding.
976  * - encoding: Set by user
977  * - decoding: unused
978  */
979  int slices;
980 
981  /** Field order
982  * - encoding: set by libavcodec
983  * - decoding: Set by user.
984  */
986 
987  /* audio only */
988  int sample_rate; ///< samples per second
989  int channels; ///< number of audio channels
990 
991  /**
992  * audio sample format
993  * - encoding: Set by user.
994  * - decoding: Set by libavcodec.
995  */
996  enum AVSampleFormat sample_fmt; ///< sample format
997 
998  /* The following data should not be initialized. */
999  /**
1000  * Number of samples per channel in an audio frame.
1001  *
1002  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1003  * except the last must contain exactly frame_size samples per channel.
1004  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1005  * frame size is not restricted.
1006  * - decoding: may be set by some decoders to indicate constant frame size
1007  */
1009 
1010  /**
1011  * Frame counter, set by libavcodec.
1012  *
1013  * - decoding: total number of frames returned from the decoder so far.
1014  * - encoding: total number of frames passed to the encoder so far.
1015  *
1016  * @note the counter is not incremented if encoding/decoding resulted in
1017  * an error.
1018  */
1020 
1021  /**
1022  * number of bytes per packet if constant and known or 0
1023  * Used by some WAV based audio codecs.
1024  */
1026 
1027  /**
1028  * Audio cutoff bandwidth (0 means "automatic")
1029  * - encoding: Set by user.
1030  * - decoding: unused
1031  */
1032  int cutoff;
1033 
1034  /**
1035  * Audio channel layout.
1036  * - encoding: set by user.
1037  * - decoding: set by user, may be overwritten by libavcodec.
1038  */
1039  uint64_t channel_layout;
1040 
1041  /**
1042  * Request decoder to use this channel layout if it can (0 for default)
1043  * - encoding: unused
1044  * - decoding: Set by user.
1045  */
1047 
1048  /**
1049  * Type of service that the audio stream conveys.
1050  * - encoding: Set by user.
1051  * - decoding: Set by libavcodec.
1052  */
1054 
1055  /**
1056  * desired sample format
1057  * - encoding: Not used.
1058  * - decoding: Set by user.
1059  * Decoder will decode to this format if it can.
1060  */
1062 
1063  /**
1064  * This callback is called at the beginning of each frame to get data
1065  * buffer(s) for it. There may be one contiguous buffer for all the data or
1066  * there may be a buffer per each data plane or anything in between. What
1067  * this means is, you may set however many entries in buf[] you feel necessary.
1068  * Each buffer must be reference-counted using the AVBuffer API (see description
1069  * of buf[] below).
1070  *
1071  * The following fields will be set in the frame before this callback is
1072  * called:
1073  * - format
1074  * - width, height (video only)
1075  * - sample_rate, channel_layout, nb_samples (audio only)
1076  * Their values may differ from the corresponding values in
1077  * AVCodecContext. This callback must use the frame values, not the codec
1078  * context values, to calculate the required buffer size.
1079  *
1080  * This callback must fill the following fields in the frame:
1081  * - data[]
1082  * - linesize[]
1083  * - extended_data:
1084  * * if the data is planar audio with more than 8 channels, then this
1085  * callback must allocate and fill extended_data to contain all pointers
1086  * to all data planes. data[] must hold as many pointers as it can.
1087  * extended_data must be allocated with av_malloc() and will be freed in
1088  * av_frame_unref().
1089  * * otherwise extended_data must point to data
1090  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1091  * the frame's data and extended_data pointers must be contained in these. That
1092  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1093  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1094  * and av_buffer_ref().
1095  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1096  * this callback and filled with the extra buffers if there are more
1097  * buffers than buf[] can hold. extended_buf will be freed in
1098  * av_frame_unref().
1099  *
1100  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1101  * avcodec_default_get_buffer2() instead of providing buffers allocated by
1102  * some other means.
1103  *
1104  * Each data plane must be aligned to the maximum required by the target
1105  * CPU.
1106  *
1107  * @see avcodec_default_get_buffer2()
1108  *
1109  * Video:
1110  *
1111  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1112  * (read and/or written to if it is writable) later by libavcodec.
1113  *
1114  * avcodec_align_dimensions2() should be used to find the required width and
1115  * height, as they normally need to be rounded up to the next multiple of 16.
1116  *
1117  * Some decoders do not support linesizes changing between frames.
1118  *
1119  * If frame multithreading is used, this callback may be called from a
1120  * different thread, but not from more than one at once. Does not need to be
1121  * reentrant.
1122  *
1123  * @see avcodec_align_dimensions2()
1124  *
1125  * Audio:
1126  *
1127  * Decoders request a buffer of a particular size by setting
1128  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1129  * however, utilize only part of the buffer by setting AVFrame.nb_samples
1130  * to a smaller value in the output frame.
1131  *
1132  * As a convenience, av_samples_get_buffer_size() and
1133  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1134  * functions to find the required data size and to fill data pointers and
1135  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1136  * since all planes must be the same size.
1137  *
1138  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1139  *
1140  * - encoding: unused
1141  * - decoding: Set by libavcodec, user can override.
1142  */
1144 
1145  /* - encoding parameters */
1146  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1147  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1148 
1149  /**
1150  * minimum quantizer
1151  * - encoding: Set by user.
1152  * - decoding: unused
1153  */
1154  int qmin;
1155 
1156  /**
1157  * maximum quantizer
1158  * - encoding: Set by user.
1159  * - decoding: unused
1160  */
1161  int qmax;
1162 
1163  /**
1164  * maximum quantizer difference between frames
1165  * - encoding: Set by user.
1166  * - decoding: unused
1167  */
1169 
1170  /**
1171  * decoder bitstream buffer size
1172  * - encoding: Set by user.
1173  * - decoding: unused
1174  */
1176 
1177  /**
1178  * ratecontrol override, see RcOverride
1179  * - encoding: Allocated/set/freed by user.
1180  * - decoding: unused
1181  */
1184 
1185  /**
1186  * maximum bitrate
1187  * - encoding: Set by user.
1188  * - decoding: Set by user, may be overwritten by libavcodec.
1189  */
1190  int64_t rc_max_rate;
1191 
1192  /**
1193  * minimum bitrate
1194  * - encoding: Set by user.
1195  * - decoding: unused
1196  */
1197  int64_t rc_min_rate;
1198 
1199  /**
1200  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1201  * - encoding: Set by user.
1202  * - decoding: unused.
1203  */
1205 
1206  /**
1207  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1208  * - encoding: Set by user.
1209  * - decoding: unused.
1210  */
1212 
1213  /**
1214  * Number of bits which should be loaded into the rc buffer before decoding starts.
1215  * - encoding: Set by user.
1216  * - decoding: unused
1217  */
1219 
1220  /**
1221  * trellis RD quantization
1222  * - encoding: Set by user.
1223  * - decoding: unused
1224  */
1225  int trellis;
1226 
1227  /**
1228  * pass1 encoding statistics output buffer
1229  * - encoding: Set by libavcodec.
1230  * - decoding: unused
1231  */
1232  char *stats_out;
1233 
1234  /**
1235  * pass2 encoding statistics input buffer
1236  * Concatenated stuff from stats_out of pass1 should be placed here.
1237  * - encoding: Allocated/set/freed by user.
1238  * - decoding: unused
1239  */
1240  char *stats_in;
1241 
1242  /**
1243  * Work around bugs in encoders which sometimes cannot be detected automatically.
1244  * - encoding: Set by user
1245  * - decoding: Set by user
1246  */
1248 #define FF_BUG_AUTODETECT 1 ///< autodetection
1249 #define FF_BUG_XVID_ILACE 4
1250 #define FF_BUG_UMP4 8
1251 #define FF_BUG_NO_PADDING 16
1252 #define FF_BUG_AMV 32
1253 #define FF_BUG_QPEL_CHROMA 64
1254 #define FF_BUG_STD_QPEL 128
1255 #define FF_BUG_QPEL_CHROMA2 256
1256 #define FF_BUG_DIRECT_BLOCKSIZE 512
1257 #define FF_BUG_EDGE 1024
1258 #define FF_BUG_HPEL_CHROMA 2048
1259 #define FF_BUG_DC_CLIP 4096
1260 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1261 #define FF_BUG_TRUNCATED 16384
1262 #define FF_BUG_IEDGE 32768
1263 
1264  /**
1265  * strictly follow the standard (MPEG-4, ...).
1266  * - encoding: Set by user.
1267  * - decoding: Set by user.
1268  * Setting this to STRICT or higher means the encoder and decoder will
1269  * generally do stupid things, whereas setting it to unofficial or lower
1270  * will mean the encoder might produce output that is not supported by all
1271  * spec-compliant decoders. Decoders don't differentiate between normal,
1272  * unofficial and experimental (that is, they always try to decode things
1273  * when they can) unless they are explicitly asked to behave stupidly
1274  * (=strictly conform to the specs)
1275  */
1277 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
1278 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
1279 #define FF_COMPLIANCE_NORMAL 0
1280 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
1281 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
1282 
1283  /**
1284  * error concealment flags
1285  * - encoding: unused
1286  * - decoding: Set by user.
1287  */
1289 #define FF_EC_GUESS_MVS 1
1290 #define FF_EC_DEBLOCK 2
1291 #define FF_EC_FAVOR_INTER 256
1292 
1293  /**
1294  * debug
1295  * - encoding: Set by user.
1296  * - decoding: Set by user.
1297  */
1298  int debug;
1299 #define FF_DEBUG_PICT_INFO 1
1300 #define FF_DEBUG_RC 2
1301 #define FF_DEBUG_BITSTREAM 4
1302 #define FF_DEBUG_MB_TYPE 8
1303 #define FF_DEBUG_QP 16
1304 #define FF_DEBUG_DCT_COEFF 0x00000040
1305 #define FF_DEBUG_SKIP 0x00000080
1306 #define FF_DEBUG_STARTCODE 0x00000100
1307 #define FF_DEBUG_ER 0x00000400
1308 #define FF_DEBUG_MMCO 0x00000800
1309 #define FF_DEBUG_BUGS 0x00001000
1310 #define FF_DEBUG_BUFFERS 0x00008000
1311 #define FF_DEBUG_THREADS 0x00010000
1312 #define FF_DEBUG_GREEN_MD 0x00800000
1313 #define FF_DEBUG_NOMC 0x01000000
1314 
1315  /**
1316  * Error recognition; may misdetect some more or less valid parts as errors.
1317  * - encoding: Set by user.
1318  * - decoding: Set by user.
1319  */
1321 
1322 /**
1323  * Verify checksums embedded in the bitstream (could be of either encoded or
1324  * decoded data, depending on the codec) and print an error message on mismatch.
1325  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
1326  * decoder returning an error.
1327  */
1328 #define AV_EF_CRCCHECK (1<<0)
1329 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
1330 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
1331 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
1332 
1333 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
1334 #define AV_EF_CAREFUL (1<<16) ///< consider things that violate the spec, are fast to calculate and have not been seen in the wild as errors
1335 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
1336 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
1337 
1338 
1339  /**
1340  * opaque 64-bit number (generally a PTS) that will be reordered and
1341  * output in AVFrame.reordered_opaque
1342  * - encoding: Set by libavcodec to the reordered_opaque of the input
1343  * frame corresponding to the last returned packet. Only
1344  * supported by encoders with the
1345  * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1346  * - decoding: Set by user.
1347  */
1349 
1350  /**
1351  * Hardware accelerator in use
1352  * - encoding: unused.
1353  * - decoding: Set by libavcodec
1354  */
1355  const struct AVHWAccel *hwaccel;
1356 
1357  /**
1358  * Hardware accelerator context.
1359  * For some hardware accelerators, a global context needs to be
1360  * provided by the user. In that case, this holds display-dependent
1361  * data FFmpeg cannot instantiate itself. Please refer to the
1362  * FFmpeg HW accelerator documentation to know how to fill this.
1363  * - encoding: unused
1364  * - decoding: Set by user
1365  */
1367 
1368  /**
1369  * error
1370  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1371  * - decoding: unused
1372  */
1374 
1375  /**
1376  * DCT algorithm, see FF_DCT_* below
1377  * - encoding: Set by user.
1378  * - decoding: unused
1379  */
1381 #define FF_DCT_AUTO 0
1382 #define FF_DCT_FASTINT 1
1383 #define FF_DCT_INT 2
1384 #define FF_DCT_MMX 3
1385 #define FF_DCT_ALTIVEC 5
1386 #define FF_DCT_FAAN 6
1387 
1388  /**
1389  * IDCT algorithm, see FF_IDCT_* below.
1390  * - encoding: Set by user.
1391  * - decoding: Set by user.
1392  */
1394 #define FF_IDCT_AUTO 0
1395 #define FF_IDCT_INT 1
1396 #define FF_IDCT_SIMPLE 2
1397 #define FF_IDCT_SIMPLEMMX 3
1398 #define FF_IDCT_ARM 7
1399 #define FF_IDCT_ALTIVEC 8
1400 #define FF_IDCT_SIMPLEARM 10
1401 #define FF_IDCT_XVID 14
1402 #define FF_IDCT_SIMPLEARMV5TE 16
1403 #define FF_IDCT_SIMPLEARMV6 17
1404 #define FF_IDCT_FAAN 20
1405 #define FF_IDCT_SIMPLENEON 22
1406 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
1407 #define FF_IDCT_SIMPLEAUTO 128
1408 
1409  /**
1410  * bits per sample/pixel from the demuxer (needed for huffyuv).
1411  * - encoding: Set by libavcodec.
1412  * - decoding: Set by user.
1413  */
1415 
1416  /**
1417  * Bits per sample/pixel of internal libavcodec pixel/sample format.
1418  * - encoding: set by user.
1419  * - decoding: set by libavcodec.
1420  */
1422 
1423  /**
1424  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1425  * - encoding: unused
1426  * - decoding: Set by user.
1427  */
1428  int lowres;
1429 
1430  /**
1431  * thread count
1432  * is used to decide how many independent tasks should be passed to execute()
1433  * - encoding: Set by user.
1434  * - decoding: Set by user.
1435  */
1437 
1438  /**
1439  * Which multithreading methods to use.
1440  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1441  * so clients which cannot provide future frames should not use it.
1442  *
1443  * - encoding: Set by user, otherwise the default is used.
1444  * - decoding: Set by user, otherwise the default is used.
1445  */
1447 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1448 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1449 
1450  /**
1451  * Which multithreading methods are in use by the codec.
1452  * - encoding: Set by libavcodec.
1453  * - decoding: Set by libavcodec.
1454  */
1456 
1457 #if FF_API_THREAD_SAFE_CALLBACKS
1458  /**
1459  * Set by the client if its custom get_buffer() callback can be called
1460  * synchronously from another thread, which allows faster multithreaded decoding.
1461  * draw_horiz_band() will be called from other threads regardless of this setting.
1462  * Ignored if the default get_buffer() is used.
1463  * - encoding: Set by user.
1464  * - decoding: Set by user.
1465  *
1466  * @deprecated the custom get_buffer2() callback should always be
1467  * thread-safe. Thread-unsafe get_buffer2() implementations will be
1468  * invalid starting with LIBAVCODEC_VERSION_MAJOR=60; in other words,
1469  * libavcodec will behave as if this field was always set to 1.
1470  * Callers that want to be forward compatible with future libavcodec
1471  * versions should wrap access to this field in
1472  * #if LIBAVCODEC_VERSION_MAJOR < 60
1473  */
1476 #endif
1477 
1478  /**
1479  * The codec may call this to execute several independent things.
1480  * It will return only after finishing all tasks.
1481  * The user may replace this with some multithreaded implementation,
1482  * the default implementation will execute the parts serially.
1483  * @param count the number of things to execute
1484  * - encoding: Set by libavcodec, user can override.
1485  * - decoding: Set by libavcodec, user can override.
1486  */
1487  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1488 
1489  /**
1490  * The codec may call this to execute several independent things.
1491  * It will return only after finishing all tasks.
1492  * The user may replace this with some multithreaded implementation,
1493  * the default implementation will execute the parts serially.
1494  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
1495  * @param c context passed also to func
1496  * @param count the number of things to execute
1497  * @param arg2 argument passed unchanged to func
1498  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1499  * @param func function that will be called count times, with jobnr from 0 to count-1.
1500  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1501  * two instances of func executing at the same time will have the same threadnr.
1502  * @return always 0 currently, but code should handle a future improvement where when any call to func
1503  * returns < 0 no further calls to func may be done and < 0 is returned.
1504  * - encoding: Set by libavcodec, user can override.
1505  * - decoding: Set by libavcodec, user can override.
1506  */
1507  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1508 
1509  /**
1510  * noise vs. sse weight for the nsse comparison function
1511  * - encoding: Set by user.
1512  * - decoding: unused
1513  */
1515 
1516  /**
1517  * profile
1518  * - encoding: Set by user.
1519  * - decoding: Set by libavcodec.
1520  */
1521  int profile;
1522 #define FF_PROFILE_UNKNOWN -99
1523 #define FF_PROFILE_RESERVED -100
1524 
1525 #define FF_PROFILE_AAC_MAIN 0
1526 #define FF_PROFILE_AAC_LOW 1
1527 #define FF_PROFILE_AAC_SSR 2
1528 #define FF_PROFILE_AAC_LTP 3
1529 #define FF_PROFILE_AAC_HE 4
1530 #define FF_PROFILE_AAC_HE_V2 28
1531 #define FF_PROFILE_AAC_LD 22
1532 #define FF_PROFILE_AAC_ELD 38
1533 #define FF_PROFILE_MPEG2_AAC_LOW 128
1534 #define FF_PROFILE_MPEG2_AAC_HE 131
1535 
1536 #define FF_PROFILE_DNXHD 0
1537 #define FF_PROFILE_DNXHR_LB 1
1538 #define FF_PROFILE_DNXHR_SQ 2
1539 #define FF_PROFILE_DNXHR_HQ 3
1540 #define FF_PROFILE_DNXHR_HQX 4
1541 #define FF_PROFILE_DNXHR_444 5
1542 
1543 #define FF_PROFILE_DTS 20
1544 #define FF_PROFILE_DTS_ES 30
1545 #define FF_PROFILE_DTS_96_24 40
1546 #define FF_PROFILE_DTS_HD_HRA 50
1547 #define FF_PROFILE_DTS_HD_MA 60
1548 #define FF_PROFILE_DTS_EXPRESS 70
1549 
1550 #define FF_PROFILE_MPEG2_422 0
1551 #define FF_PROFILE_MPEG2_HIGH 1
1552 #define FF_PROFILE_MPEG2_SS 2
1553 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1554 #define FF_PROFILE_MPEG2_MAIN 4
1555 #define FF_PROFILE_MPEG2_SIMPLE 5
1556 
1557 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1558 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1559 
1560 #define FF_PROFILE_H264_BASELINE 66
1561 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1562 #define FF_PROFILE_H264_MAIN 77
1563 #define FF_PROFILE_H264_EXTENDED 88
1564 #define FF_PROFILE_H264_HIGH 100
1565 #define FF_PROFILE_H264_HIGH_10 110
1566 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1567 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1568 #define FF_PROFILE_H264_HIGH_422 122
1569 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1570 #define FF_PROFILE_H264_STEREO_HIGH 128
1571 #define FF_PROFILE_H264_HIGH_444 144
1572 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1573 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1574 #define FF_PROFILE_H264_CAVLC_444 44
1575 
1576 #define FF_PROFILE_VC1_SIMPLE 0
1577 #define FF_PROFILE_VC1_MAIN 1
1578 #define FF_PROFILE_VC1_COMPLEX 2
1579 #define FF_PROFILE_VC1_ADVANCED 3
1580 
1581 #define FF_PROFILE_MPEG4_SIMPLE 0
1582 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1583 #define FF_PROFILE_MPEG4_CORE 2
1584 #define FF_PROFILE_MPEG4_MAIN 3
1585 #define FF_PROFILE_MPEG4_N_BIT 4
1586 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1587 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1588 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1589 #define FF_PROFILE_MPEG4_HYBRID 8
1590 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1591 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1592 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1593 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1594 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1595 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1596 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1597 
1598 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1599 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1600 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1601 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1602 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1603 
1604 #define FF_PROFILE_VP9_0 0
1605 #define FF_PROFILE_VP9_1 1
1606 #define FF_PROFILE_VP9_2 2
1607 #define FF_PROFILE_VP9_3 3
1608 
1609 #define FF_PROFILE_HEVC_MAIN 1
1610 #define FF_PROFILE_HEVC_MAIN_10 2
1611 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1612 #define FF_PROFILE_HEVC_REXT 4
1613 
1614 #define FF_PROFILE_VVC_MAIN_10 1
1615 #define FF_PROFILE_VVC_MAIN_10_444 33
1616 
1617 #define FF_PROFILE_AV1_MAIN 0
1618 #define FF_PROFILE_AV1_HIGH 1
1619 #define FF_PROFILE_AV1_PROFESSIONAL 2
1620 
1621 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1622 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1623 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1624 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1625 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1626 
1627 #define FF_PROFILE_SBC_MSBC 1
1628 
1629 #define FF_PROFILE_PRORES_PROXY 0
1630 #define FF_PROFILE_PRORES_LT 1
1631 #define FF_PROFILE_PRORES_STANDARD 2
1632 #define FF_PROFILE_PRORES_HQ 3
1633 #define FF_PROFILE_PRORES_4444 4
1634 #define FF_PROFILE_PRORES_XQ 5
1635 
1636 #define FF_PROFILE_ARIB_PROFILE_A 0
1637 #define FF_PROFILE_ARIB_PROFILE_C 1
1638 
1639 #define FF_PROFILE_KLVA_SYNC 0
1640 #define FF_PROFILE_KLVA_ASYNC 1
1641 
1642  /**
1643  * level
1644  * - encoding: Set by user.
1645  * - decoding: Set by libavcodec.
1646  */
1647  int level;
1648 #define FF_LEVEL_UNKNOWN -99
1649 
1650  /**
1651  * Skip loop filtering for selected frames.
1652  * - encoding: unused
1653  * - decoding: Set by user.
1654  */
1656 
1657  /**
1658  * Skip IDCT/dequantization for selected frames.
1659  * - encoding: unused
1660  * - decoding: Set by user.
1661  */
1663 
1664  /**
1665  * Skip decoding for selected frames.
1666  * - encoding: unused
1667  * - decoding: Set by user.
1668  */
1670 
1671  /**
1672  * Header containing style information for text subtitles.
1673  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
1674  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
1675  * the Format line following. It shouldn't include any Dialogue line.
1676  * - encoding: Set/allocated/freed by user (before avcodec_open2())
1677  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
1678  */
1681 
1682  /**
1683  * Audio only. The number of "priming" samples (padding) inserted by the
1684  * encoder at the beginning of the audio. I.e. this number of leading
1685  * decoded samples must be discarded by the caller to get the original audio
1686  * without leading padding.
1687  *
1688  * - decoding: unused
1689  * - encoding: Set by libavcodec. The timestamps on the output packets are
1690  * adjusted by the encoder so that they always refer to the
1691  * first sample of the data actually contained in the packet,
1692  * including any added padding. E.g. if the timebase is
1693  * 1/samplerate and the timestamp of the first input sample is
1694  * 0, the timestamp of the first output packet will be
1695  * -initial_padding.
1696  */
1698 
1699  /**
1700  * - decoding: For codecs that store a framerate value in the compressed
1701  * bitstream, the decoder may export it here. { 0, 1} when
1702  * unknown.
1703  * - encoding: May be used to signal the framerate of CFR content to an
1704  * encoder.
1705  */
1707 
1708  /**
1709  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
1710  * - encoding: unused.
1711  * - decoding: Set by libavcodec before calling get_format()
1712  */
1714 
1715  /**
1716  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
1717  * - encoding unused.
1718  * - decoding set by user.
1719  */
1721 
1722  /**
1723  * AVCodecDescriptor
1724  * - encoding: unused.
1725  * - decoding: set by libavcodec.
1726  */
1728 
1729  /**
1730  * Current statistics for PTS correction.
1731  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
1732  * - encoding: unused
1733  */
1734  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
1735  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
1736  int64_t pts_correction_last_pts; /// PTS of the last frame
1737  int64_t pts_correction_last_dts; /// DTS of the last frame
1738 
1739  /**
1740  * Character encoding of the input subtitles file.
1741  * - decoding: set by user
1742  * - encoding: unused
1743  */
1745 
1746  /**
1747  * Subtitles character encoding mode. Formats or codecs might be adjusting
1748  * this setting (if they are doing the conversion themselves for instance).
1749  * - decoding: set by libavcodec
1750  * - encoding: unused
1751  */
1753 #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)
1754 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
1755 #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
1756 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
1757 
1758  /**
1759  * Skip processing alpha if supported by codec.
1760  * Note that if the format uses pre-multiplied alpha (common with VP6,
1761  * and recommended due to better video quality/compression)
1762  * the image will look as if alpha-blended onto a black background.
1763  * However for formats that do not use pre-multiplied alpha
1764  * there might be serious artefacts (though e.g. libswscale currently
1765  * assumes pre-multiplied alpha anyway).
1766  *
1767  * - decoding: set by user
1768  * - encoding: unused
1769  */
1771 
1772  /**
1773  * Number of samples to skip after a discontinuity
1774  * - decoding: unused
1775  * - encoding: set by libavcodec
1776  */
1778 
1779 #if FF_API_DEBUG_MV
1780  /**
1781  * @deprecated unused
1782  */
1785 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
1786 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
1787 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
1788 #endif
1789 
1790  /**
1791  * custom intra quantization matrix
1792  * - encoding: Set by user, can be NULL.
1793  * - decoding: unused.
1794  */
1796 
1797  /**
1798  * dump format separator.
1799  * can be ", " or "\n " or anything else
1800  * - encoding: Set by user.
1801  * - decoding: Set by user.
1802  */
1803  uint8_t *dump_separator;
1804 
1805  /**
1806  * ',' separated list of allowed decoders.
1807  * If NULL then all are allowed
1808  * - encoding: unused
1809  * - decoding: set by user
1810  */
1812 
1813  /**
1814  * Properties of the stream that gets decoded
1815  * - encoding: unused
1816  * - decoding: set by libavcodec
1817  */
1818  unsigned properties;
1819 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
1820 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
1821 
1822  /**
1823  * Additional data associated with the entire coded stream.
1824  *
1825  * - decoding: unused
1826  * - encoding: may be set by libavcodec after avcodec_open2().
1827  */
1830 
1831  /**
1832  * A reference to the AVHWFramesContext describing the input (for encoding)
1833  * or output (decoding) frames. The reference is set by the caller and
1834  * afterwards owned (and freed) by libavcodec - it should never be read by
1835  * the caller after being set.
1836  *
1837  * - decoding: This field should be set by the caller from the get_format()
1838  * callback. The previous reference (if any) will always be
1839  * unreffed by libavcodec before the get_format() call.
1840  *
1841  * If the default get_buffer2() is used with a hwaccel pixel
1842  * format, then this AVHWFramesContext will be used for
1843  * allocating the frame buffers.
1844  *
1845  * - encoding: For hardware encoders configured to use a hwaccel pixel
1846  * format, this field should be set by the caller to a reference
1847  * to the AVHWFramesContext describing input frames.
1848  * AVHWFramesContext.format must be equal to
1849  * AVCodecContext.pix_fmt.
1850  *
1851  * This field should be set before avcodec_open2() is called.
1852  */
1854 
1855  /**
1856  * Control the form of AVSubtitle.rects[N]->ass
1857  * - decoding: set by user
1858  * - encoding: unused
1859  */
1861 #define FF_SUB_TEXT_FMT_ASS 0
1862 
1863  /**
1864  * Audio only. The amount of padding (in samples) appended by the encoder to
1865  * the end of the audio. I.e. this number of decoded samples must be
1866  * discarded by the caller from the end of the stream to get the original
1867  * audio without any trailing padding.
1868  *
1869  * - decoding: unused
1870  * - encoding: unused
1871  */
1873 
1874  /**
1875  * The number of pixels per image to maximally accept.
1876  *
1877  * - decoding: set by user
1878  * - encoding: set by user
1879  */
1880  int64_t max_pixels;
1881 
1882  /**
1883  * A reference to the AVHWDeviceContext describing the device which will
1884  * be used by a hardware encoder/decoder. The reference is set by the
1885  * caller and afterwards owned (and freed) by libavcodec.
1886  *
1887  * This should be used if either the codec device does not require
1888  * hardware frames or any that are used are to be allocated internally by
1889  * libavcodec. If the user wishes to supply any of the frames used as
1890  * encoder input or decoder output then hw_frames_ctx should be used
1891  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
1892  * field will be ignored while decoding the associated stream segment, but
1893  * may again be used on a following one after another get_format() call.
1894  *
1895  * For both encoders and decoders this field should be set before
1896  * avcodec_open2() is called and must not be written to thereafter.
1897  *
1898  * Note that some decoders may require this field to be set initially in
1899  * order to support hw_frames_ctx at all - in that case, all frames
1900  * contexts used must be created on the same device.
1901  */
1903 
1904  /**
1905  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
1906  * decoding (if active).
1907  * - encoding: unused
1908  * - decoding: Set by user (either before avcodec_open2(), or in the
1909  * AVCodecContext.get_format callback)
1910  */
1912 
1913  /**
1914  * Video decoding only. Certain video codecs support cropping, meaning that
1915  * only a sub-rectangle of the decoded frame is intended for display. This
1916  * option controls how cropping is handled by libavcodec.
1917  *
1918  * When set to 1 (the default), libavcodec will apply cropping internally.
1919  * I.e. it will modify the output frame width/height fields and offset the
1920  * data pointers (only by as much as possible while preserving alignment, or
1921  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
1922  * the frames output by the decoder refer only to the cropped area. The
1923  * crop_* fields of the output frames will be zero.
1924  *
1925  * When set to 0, the width/height fields of the output frames will be set
1926  * to the coded dimensions and the crop_* fields will describe the cropping
1927  * rectangle. Applying the cropping is left to the caller.
1928  *
1929  * @warning When hardware acceleration with opaque output frames is used,
1930  * libavcodec is unable to apply cropping from the top/left border.
1931  *
1932  * @note when this option is set to zero, the width/height fields of the
1933  * AVCodecContext and output AVFrames have different meanings. The codec
1934  * context fields store display dimensions (with the coded dimensions in
1935  * coded_width/height), while the frame fields store the coded dimensions
1936  * (with the display dimensions being determined by the crop_* fields).
1937  */
1939 
1940  /*
1941  * Video decoding only. Sets the number of extra hardware frames which
1942  * the decoder will allocate for use by the caller. This must be set
1943  * before avcodec_open2() is called.
1944  *
1945  * Some hardware decoders require all frames that they will use for
1946  * output to be defined in advance before decoding starts. For such
1947  * decoders, the hardware frame pool must therefore be of a fixed size.
1948  * The extra frames set here are on top of any number that the decoder
1949  * needs internally in order to operate normally (for example, frames
1950  * used as reference pictures).
1951  */
1953 
1954  /**
1955  * The percentage of damaged samples to discard a frame.
1956  *
1957  * - decoding: set by user
1958  * - encoding: unused
1959  */
1961 
1962  /**
1963  * The number of samples per frame to maximally accept.
1964  *
1965  * - decoding: set by user
1966  * - encoding: set by user
1967  */
1968  int64_t max_samples;
1969 
1970  /**
1971  * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
1972  * metadata exported in frame, packet, or coded stream side data by
1973  * decoders and encoders.
1974  *
1975  * - decoding: set by user
1976  * - encoding: set by user
1977  */
1979 
1980  /**
1981  * This callback is called at the beginning of each packet to get a data
1982  * buffer for it.
1983  *
1984  * The following field will be set in the packet before this callback is
1985  * called:
1986  * - size
1987  * This callback must use the above value to calculate the required buffer size,
1988  * which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
1989  *
1990  * In some specific cases, the encoder may not use the entire buffer allocated by this
1991  * callback. This will be reflected in the size value in the packet once returned by
1992  * avcodec_receive_packet().
1993  *
1994  * This callback must fill the following fields in the packet:
1995  * - data: alignment requirements for AVPacket apply, if any. Some architectures and
1996  * encoders may benefit from having aligned data.
1997  * - buf: must contain a pointer to an AVBufferRef structure. The packet's
1998  * data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
1999  * and av_buffer_ref().
2000  *
2001  * If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2002  * avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2003  * some other means.
2004  *
2005  * The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2006  * They may be used for example to hint what use the buffer may get after being
2007  * created.
2008  * Implementations of this callback may ignore flags they don't understand.
2009  * If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2010  * (read and/or written to if it is writable) later by libavcodec.
2011  *
2012  * This callback must be thread-safe, as when frame threading is used, it may
2013  * be called from multiple threads simultaneously.
2014  *
2015  * @see avcodec_default_get_encode_buffer()
2016  *
2017  * - encoding: Set by libavcodec, user can override.
2018  * - decoding: unused
2019  */
2021 } AVCodecContext;
2022 
2023 struct MpegEncContext;
2024 
2025 /**
2026  * @defgroup lavc_hwaccel AVHWAccel
2027  *
2028  * @note Nothing in this structure should be accessed by the user. At some
2029  * point in future it will not be externally visible at all.
2030  *
2031  * @{
2032  */
2033 typedef struct AVHWAccel {
2034  /**
2035  * Name of the hardware accelerated codec.
2036  * The name is globally unique among encoders and among decoders (but an
2037  * encoder and a decoder can share the same name).
2038  */
2039  const char *name;
2040 
2041  /**
2042  * Type of codec implemented by the hardware accelerator.
2043  *
2044  * See AVMEDIA_TYPE_xxx
2045  */
2047 
2048  /**
2049  * Codec implemented by the hardware accelerator.
2050  *
2051  * See AV_CODEC_ID_xxx
2052  */
2054 
2055  /**
2056  * Supported pixel format.
2057  *
2058  * Only hardware accelerated formats are supported here.
2059  */
2061 
2062  /**
2063  * Hardware accelerated codec capabilities.
2064  * see AV_HWACCEL_CODEC_CAP_*
2065  */
2067 
2068  /*****************************************************************
2069  * No fields below this line are part of the public API. They
2070  * may not be used outside of libavcodec and can be changed and
2071  * removed at will.
2072  * New public fields should be added right above.
2073  *****************************************************************
2074  */
2075 
2076  /**
2077  * Allocate a custom buffer
2078  */
2080 
2081  /**
2082  * Called at the beginning of each frame or field picture.
2083  *
2084  * Meaningful frame information (codec specific) is guaranteed to
2085  * be parsed at this point. This function is mandatory.
2086  *
2087  * Note that buf can be NULL along with buf_size set to 0.
2088  * Otherwise, this means the whole frame is available at this point.
2089  *
2090  * @param avctx the codec context
2091  * @param buf the frame data buffer base
2092  * @param buf_size the size of the frame in bytes
2093  * @return zero if successful, a negative value otherwise
2094  */
2095  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2096 
2097  /**
2098  * Callback for parameter data (SPS/PPS/VPS etc).
2099  *
2100  * Useful for hardware decoders which keep persistent state about the
2101  * video parameters, and need to receive any changes to update that state.
2102  *
2103  * @param avctx the codec context
2104  * @param type the nal unit type
2105  * @param buf the nal unit data buffer
2106  * @param buf_size the size of the nal unit in bytes
2107  * @return zero if successful, a negative value otherwise
2108  */
2109  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
2110 
2111  /**
2112  * Callback for each slice.
2113  *
2114  * Meaningful slice information (codec specific) is guaranteed to
2115  * be parsed at this point. This function is mandatory.
2116  * The only exception is XvMC, that works on MB level.
2117  *
2118  * @param avctx the codec context
2119  * @param buf the slice data buffer base
2120  * @param buf_size the size of the slice in bytes
2121  * @return zero if successful, a negative value otherwise
2122  */
2123  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2124 
2125  /**
2126  * Called at the end of each frame or field picture.
2127  *
2128  * The whole picture is parsed at this point and can now be sent
2129  * to the hardware accelerator. This function is mandatory.
2130  *
2131  * @param avctx the codec context
2132  * @return zero if successful, a negative value otherwise
2133  */
2135 
2136  /**
2137  * Size of per-frame hardware accelerator private data.
2138  *
2139  * Private data is allocated with av_mallocz() before
2140  * AVCodecContext.get_buffer() and deallocated after
2141  * AVCodecContext.release_buffer().
2142  */
2144 
2145  /**
2146  * Called for every Macroblock in a slice.
2147  *
2148  * XvMC uses it to replace the ff_mpv_reconstruct_mb().
2149  * Instead of decoding to raw picture, MB parameters are
2150  * stored in an array provided by the video driver.
2151  *
2152  * @param s the mpeg context
2153  */
2154  void (*decode_mb)(struct MpegEncContext *s);
2155 
2156  /**
2157  * Initialize the hwaccel private data.
2158  *
2159  * This will be called from ff_get_format(), after hwaccel and
2160  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
2161  * is allocated.
2162  */
2164 
2165  /**
2166  * Uninitialize the hwaccel private data.
2167  *
2168  * This will be called from get_format() or avcodec_close(), after hwaccel
2169  * and hwaccel_context are already uninitialized.
2170  */
2172 
2173  /**
2174  * Size of the private data to allocate in
2175  * AVCodecInternal.hwaccel_priv_data.
2176  */
2178 
2179  /**
2180  * Internal hwaccel capabilities.
2181  */
2183 
2184  /**
2185  * Fill the given hw_frames context with current codec parameters. Called
2186  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
2187  * details.
2188  *
2189  * This CAN be called before AVHWAccel.init is called, and you must assume
2190  * that avctx->hwaccel_priv_data is invalid.
2191  */
2193 } AVHWAccel;
2194 
2195 /**
2196  * HWAccel is experimental and is thus avoided in favor of non experimental
2197  * codecs
2198  */
2199 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2200 
2201 /**
2202  * Hardware acceleration should be used for decoding even if the codec level
2203  * used is unknown or higher than the maximum supported level reported by the
2204  * hardware driver.
2205  *
2206  * It's generally a good idea to pass this flag unless you have a specific
2207  * reason not to, as hardware tends to under-report supported levels.
2208  */
2209 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2210 
2211 /**
2212  * Hardware acceleration can output YUV pixel formats with a different chroma
2213  * sampling than 4:2:0 and/or other than 8 bits per component.
2214  */
2215 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2216 
2217 /**
2218  * Hardware acceleration should still be attempted for decoding when the
2219  * codec profile does not match the reported capabilities of the hardware.
2220  *
2221  * For example, this can be used to try to decode baseline profile H.264
2222  * streams in hardware - it will often succeed, because many streams marked
2223  * as baseline profile actually conform to constrained baseline profile.
2224  *
2225  * @warning If the stream is actually not supported then the behaviour is
2226  * undefined, and may include returning entirely incorrect output
2227  * while indicating success.
2228  */
2229 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2230 
2231 /**
2232  * @}
2233  */
2234 
2237 
2238  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2239 
2240  /**
2241  * Plain text, the text field must be set by the decoder and is
2242  * authoritative. ass and pict fields may contain approximations.
2243  */
2245 
2246  /**
2247  * Formatted text, the ass field must be set by the decoder and is
2248  * authoritative. pict and text fields may contain approximations.
2249  */
2251 };
2252 
2253 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
2254 
2255 typedef struct AVSubtitleRect {
2256  int x; ///< top left corner of pict, undefined when pict is not set
2257  int y; ///< top left corner of pict, undefined when pict is not set
2258  int w; ///< width of pict, undefined when pict is not set
2259  int h; ///< height of pict, undefined when pict is not set
2260  int nb_colors; ///< number of colors in pict, undefined when pict is not set
2261 
2262  /**
2263  * data+linesize for the bitmap of this subtitle.
2264  * Can be set for text/ass as well once they are rendered.
2265  */
2266  uint8_t *data[4];
2267  int linesize[4];
2268 
2270 
2271  char *text; ///< 0 terminated plain UTF-8 text
2272 
2273  /**
2274  * 0 terminated ASS/SSA compatible event line.
2275  * The presentation of this is unaffected by the other values in this
2276  * struct.
2277  */
2278  char *ass;
2279 
2280  int flags;
2281 } AVSubtitleRect;
2282 
2283 typedef struct AVSubtitle {
2284  uint16_t format; /* 0 = graphics */
2285  uint32_t start_display_time; /* relative to packet pts, in ms */
2286  uint32_t end_display_time; /* relative to packet pts, in ms */
2287  unsigned num_rects;
2289  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2290 } AVSubtitle;
2291 
2292 /**
2293  * Return the LIBAVCODEC_VERSION_INT constant.
2294  */
2295 unsigned avcodec_version(void);
2296 
2297 /**
2298  * Return the libavcodec build-time configuration.
2299  */
2300 const char *avcodec_configuration(void);
2301 
2302 /**
2303  * Return the libavcodec license.
2304  */
2305 const char *avcodec_license(void);
2306 
2307 /**
2308  * Allocate an AVCodecContext and set its fields to default values. The
2309  * resulting struct should be freed with avcodec_free_context().
2310  *
2311  * @param codec if non-NULL, allocate private data and initialize defaults
2312  * for the given codec. It is illegal to then call avcodec_open2()
2313  * with a different codec.
2314  * If NULL, then the codec-specific defaults won't be initialized,
2315  * which may result in suboptimal default settings (this is
2316  * important mainly for encoders, e.g. libx264).
2317  *
2318  * @return An AVCodecContext filled with default values or NULL on failure.
2319  */
2321 
2322 /**
2323  * Free the codec context and everything associated with it and write NULL to
2324  * the provided pointer.
2325  */
2326 void avcodec_free_context(AVCodecContext **avctx);
2327 
2328 /**
2329  * Get the AVClass for AVCodecContext. It can be used in combination with
2330  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2331  *
2332  * @see av_opt_find().
2333  */
2334 const AVClass *avcodec_get_class(void);
2335 
2336 #if FF_API_GET_FRAME_CLASS
2337 /**
2338  * @deprecated This function should not be used.
2339  */
2341 const AVClass *avcodec_get_frame_class(void);
2342 #endif
2343 
2344 /**
2345  * Get the AVClass for AVSubtitleRect. It can be used in combination with
2346  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2347  *
2348  * @see av_opt_find().
2349  */
2351 
2352 /**
2353  * Fill the parameters struct based on the values from the supplied codec
2354  * context. Any allocated fields in par are freed and replaced with duplicates
2355  * of the corresponding fields in codec.
2356  *
2357  * @return >= 0 on success, a negative AVERROR code on failure
2358  */
2360  const AVCodecContext *codec);
2361 
2362 /**
2363  * Fill the codec context based on the values from the supplied codec
2364  * parameters. Any allocated fields in codec that have a corresponding field in
2365  * par are freed and replaced with duplicates of the corresponding field in par.
2366  * Fields in codec that do not have a counterpart in par are not touched.
2367  *
2368  * @return >= 0 on success, a negative AVERROR code on failure.
2369  */
2371  const AVCodecParameters *par);
2372 
2373 /**
2374  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2375  * function the context has to be allocated with avcodec_alloc_context3().
2376  *
2377  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2378  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2379  * retrieving a codec.
2380  *
2381  * @warning This function is not thread safe!
2382  *
2383  * @note Always call this function before using decoding routines (such as
2384  * @ref avcodec_receive_frame()).
2385  *
2386  * @code
2387  * av_dict_set(&opts, "b", "2.5M", 0);
2388  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2389  * if (!codec)
2390  * exit(1);
2391  *
2392  * context = avcodec_alloc_context3(codec);
2393  *
2394  * if (avcodec_open2(context, codec, opts) < 0)
2395  * exit(1);
2396  * @endcode
2397  *
2398  * @param avctx The context to initialize.
2399  * @param codec The codec to open this context for. If a non-NULL codec has been
2400  * previously passed to avcodec_alloc_context3() or
2401  * for this context, then this parameter MUST be either NULL or
2402  * equal to the previously passed codec.
2403  * @param options A dictionary filled with AVCodecContext and codec-private options.
2404  * On return this object will be filled with options that were not found.
2405  *
2406  * @return zero on success, a negative value on error
2407  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2408  * av_dict_set(), av_opt_find().
2409  */
2410 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2411 
2412 /**
2413  * Close a given AVCodecContext and free all the data associated with it
2414  * (but not the AVCodecContext itself).
2415  *
2416  * Calling this function on an AVCodecContext that hasn't been opened will free
2417  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2418  * codec. Subsequent calls will do nothing.
2419  *
2420  * @note Do not use this function. Use avcodec_free_context() to destroy a
2421  * codec context (either open or closed). Opening and closing a codec context
2422  * multiple times is not supported anymore -- use multiple codec contexts
2423  * instead.
2424  */
2425 int avcodec_close(AVCodecContext *avctx);
2426 
2427 /**
2428  * Free all allocated data in the given subtitle struct.
2429  *
2430  * @param sub AVSubtitle to free.
2431  */
2433 
2434 /**
2435  * @}
2436  */
2437 
2438 /**
2439  * @addtogroup lavc_decoding
2440  * @{
2441  */
2442 
2443 /**
2444  * The default callback for AVCodecContext.get_buffer2(). It is made public so
2445  * it can be called by custom get_buffer2() implementations for decoders without
2446  * AV_CODEC_CAP_DR1 set.
2447  */
2449 
2450 /**
2451  * The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2452  * it can be called by custom get_encode_buffer() implementations for encoders without
2453  * AV_CODEC_CAP_DR1 set.
2454  */
2456 
2457 /**
2458  * Modify width and height values so that they will result in a memory
2459  * buffer that is acceptable for the codec if you do not use any horizontal
2460  * padding.
2461  *
2462  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2463  */
2465 
2466 /**
2467  * Modify width and height values so that they will result in a memory
2468  * buffer that is acceptable for the codec if you also ensure that all
2469  * line sizes are a multiple of the respective linesize_align[i].
2470  *
2471  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2472  */
2474  int linesize_align[AV_NUM_DATA_POINTERS]);
2475 
2476 /**
2477  * Converts AVChromaLocation to swscale x/y chroma position.
2478  *
2479  * The positions represent the chroma (0,0) position in a coordinates system
2480  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2481  *
2482  * @param xpos horizontal chroma sample position
2483  * @param ypos vertical chroma sample position
2484  */
2485 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
2486 
2487 /**
2488  * Converts swscale x/y chroma position to AVChromaLocation.
2489  *
2490  * The positions represent the chroma (0,0) position in a coordinates system
2491  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2492  *
2493  * @param xpos horizontal chroma sample position
2494  * @param ypos vertical chroma sample position
2495  */
2496 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
2497 
2498 /**
2499  * Decode a subtitle message.
2500  * Return a negative value on error, otherwise return the number of bytes used.
2501  * If no subtitle could be decompressed, got_sub_ptr is zero.
2502  * Otherwise, the subtitle is stored in *sub.
2503  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
2504  * simplicity, because the performance difference is expected to be negligible
2505  * and reusing a get_buffer written for video codecs would probably perform badly
2506  * due to a potentially very different allocation pattern.
2507  *
2508  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2509  * and output. This means that for some packets they will not immediately
2510  * produce decoded output and need to be flushed at the end of decoding to get
2511  * all the decoded data. Flushing is done by calling this function with packets
2512  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2513  * returning subtitles. It is safe to flush even those decoders that are not
2514  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
2515  *
2516  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2517  * before packets may be fed to the decoder.
2518  *
2519  * @param avctx the codec context
2520  * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
2521  * must be freed with avsubtitle_free if *got_sub_ptr is set.
2522  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
2523  * @param[in] avpkt The input AVPacket containing the input buffer.
2524  */
2526  int *got_sub_ptr,
2527  AVPacket *avpkt);
2528 
2529 /**
2530  * Supply raw packet data as input to a decoder.
2531  *
2532  * Internally, this call will copy relevant AVCodecContext fields, which can
2533  * influence decoding per-packet, and apply them when the packet is actually
2534  * decoded. (For example AVCodecContext.skip_frame, which might direct the
2535  * decoder to drop the frame contained by the packet sent with this function.)
2536  *
2537  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2538  * larger than the actual read bytes because some optimized bitstream
2539  * readers read 32 or 64 bits at once and could read over the end.
2540  *
2541  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2542  * before packets may be fed to the decoder.
2543  *
2544  * @param avctx codec context
2545  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
2546  * frame, or several complete audio frames.
2547  * Ownership of the packet remains with the caller, and the
2548  * decoder will not write to the packet. The decoder may create
2549  * a reference to the packet data (or copy it if the packet is
2550  * not reference-counted).
2551  * Unlike with older APIs, the packet is always fully consumed,
2552  * and if it contains multiple frames (e.g. some audio codecs),
2553  * will require you to call avcodec_receive_frame() multiple
2554  * times afterwards before you can send a new packet.
2555  * It can be NULL (or an AVPacket with data set to NULL and
2556  * size set to 0); in this case, it is considered a flush
2557  * packet, which signals the end of the stream. Sending the
2558  * first flush packet will return success. Subsequent ones are
2559  * unnecessary and will return AVERROR_EOF. If the decoder
2560  * still has frames buffered, it will return them after sending
2561  * a flush packet.
2562  *
2563  * @return 0 on success, otherwise negative error code:
2564  * AVERROR(EAGAIN): input is not accepted in the current state - user
2565  * must read output with avcodec_receive_frame() (once
2566  * all output is read, the packet should be resent, and
2567  * the call will not fail with EAGAIN).
2568  * AVERROR_EOF: the decoder has been flushed, and no new packets can
2569  * be sent to it (also returned if more than 1 flush
2570  * packet is sent)
2571  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
2572  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
2573  * other errors: legitimate decoding errors
2574  */
2575 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
2576 
2577 /**
2578  * Return decoded output data from a decoder.
2579  *
2580  * @param avctx codec context
2581  * @param frame This will be set to a reference-counted video or audio
2582  * frame (depending on the decoder type) allocated by the
2583  * decoder. Note that the function will always call
2584  * av_frame_unref(frame) before doing anything else.
2585  *
2586  * @return
2587  * 0: success, a frame was returned
2588  * AVERROR(EAGAIN): output is not available in this state - user must try
2589  * to send new input
2590  * AVERROR_EOF: the decoder has been fully flushed, and there will be
2591  * no more output frames
2592  * AVERROR(EINVAL): codec not opened, or it is an encoder
2593  * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
2594  * with respect to first decoded frame. Applicable
2595  * when flag AV_CODEC_FLAG_DROPCHANGED is set.
2596  * other negative values: legitimate decoding errors
2597  */
2599 
2600 /**
2601  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
2602  * to retrieve buffered output packets.
2603  *
2604  * @param avctx codec context
2605  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
2606  * Ownership of the frame remains with the caller, and the
2607  * encoder will not write to the frame. The encoder may create
2608  * a reference to the frame data (or copy it if the frame is
2609  * not reference-counted).
2610  * It can be NULL, in which case it is considered a flush
2611  * packet. This signals the end of the stream. If the encoder
2612  * still has packets buffered, it will return them after this
2613  * call. Once flushing mode has been entered, additional flush
2614  * packets are ignored, and sending frames will return
2615  * AVERROR_EOF.
2616  *
2617  * For audio:
2618  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
2619  * can have any number of samples.
2620  * If it is not set, frame->nb_samples must be equal to
2621  * avctx->frame_size for all frames except the last.
2622  * The final frame may be smaller than avctx->frame_size.
2623  * @return 0 on success, otherwise negative error code:
2624  * AVERROR(EAGAIN): input is not accepted in the current state - user
2625  * must read output with avcodec_receive_packet() (once
2626  * all output is read, the packet should be resent, and
2627  * the call will not fail with EAGAIN).
2628  * AVERROR_EOF: the encoder has been flushed, and no new frames can
2629  * be sent to it
2630  * AVERROR(EINVAL): codec not opened, it is a decoder, or requires flush
2631  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
2632  * other errors: legitimate encoding errors
2633  */
2634 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
2635 
2636 /**
2637  * Read encoded data from the encoder.
2638  *
2639  * @param avctx codec context
2640  * @param avpkt This will be set to a reference-counted packet allocated by the
2641  * encoder. Note that the function will always call
2642  * av_packet_unref(avpkt) before doing anything else.
2643  * @return 0 on success, otherwise negative error code:
2644  * AVERROR(EAGAIN): output is not available in the current state - user
2645  * must try to send input
2646  * AVERROR_EOF: the encoder has been fully flushed, and there will be
2647  * no more output packets
2648  * AVERROR(EINVAL): codec not opened, or it is a decoder
2649  * other errors: legitimate encoding errors
2650  */
2651 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
2652 
2653 /**
2654  * Create and return a AVHWFramesContext with values adequate for hardware
2655  * decoding. This is meant to get called from the get_format callback, and is
2656  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
2657  * This API is for decoding with certain hardware acceleration modes/APIs only.
2658  *
2659  * The returned AVHWFramesContext is not initialized. The caller must do this
2660  * with av_hwframe_ctx_init().
2661  *
2662  * Calling this function is not a requirement, but makes it simpler to avoid
2663  * codec or hardware API specific details when manually allocating frames.
2664  *
2665  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
2666  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
2667  * it unnecessary to call this function or having to care about
2668  * AVHWFramesContext initialization at all.
2669  *
2670  * There are a number of requirements for calling this function:
2671  *
2672  * - It must be called from get_format with the same avctx parameter that was
2673  * passed to get_format. Calling it outside of get_format is not allowed, and
2674  * can trigger undefined behavior.
2675  * - The function is not always supported (see description of return values).
2676  * Even if this function returns successfully, hwaccel initialization could
2677  * fail later. (The degree to which implementations check whether the stream
2678  * is actually supported varies. Some do this check only after the user's
2679  * get_format callback returns.)
2680  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
2681  * user decides to use a AVHWFramesContext prepared with this API function,
2682  * the user must return the same hw_pix_fmt from get_format.
2683  * - The device_ref passed to this function must support the given hw_pix_fmt.
2684  * - After calling this API function, it is the user's responsibility to
2685  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
2686  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
2687  * before returning from get_format (this is implied by the normal
2688  * AVCodecContext.hw_frames_ctx API rules).
2689  * - The AVHWFramesContext parameters may change every time time get_format is
2690  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
2691  * you are inherently required to go through this process again on every
2692  * get_format call.
2693  * - It is perfectly possible to call this function without actually using
2694  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
2695  * previously initialized AVHWFramesContext, and calling this API function
2696  * only to test whether the required frame parameters have changed.
2697  * - Fields that use dynamically allocated values of any kind must not be set
2698  * by the user unless setting them is explicitly allowed by the documentation.
2699  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
2700  * the new free callback must call the potentially set previous free callback.
2701  * This API call may set any dynamically allocated fields, including the free
2702  * callback.
2703  *
2704  * The function will set at least the following fields on AVHWFramesContext
2705  * (potentially more, depending on hwaccel API):
2706  *
2707  * - All fields set by av_hwframe_ctx_alloc().
2708  * - Set the format field to hw_pix_fmt.
2709  * - Set the sw_format field to the most suited and most versatile format. (An
2710  * implication is that this will prefer generic formats over opaque formats
2711  * with arbitrary restrictions, if possible.)
2712  * - Set the width/height fields to the coded frame size, rounded up to the
2713  * API-specific minimum alignment.
2714  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
2715  * field to the number of maximum reference surfaces possible with the codec,
2716  * plus 1 surface for the user to work (meaning the user can safely reference
2717  * at most 1 decoded surface at a time), plus additional buffering introduced
2718  * by frame threading. If the hwaccel does not require pre-allocation, the
2719  * field is left to 0, and the decoder will allocate new surfaces on demand
2720  * during decoding.
2721  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
2722  * hardware API.
2723  *
2724  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
2725  * with basic frame parameters set.
2726  *
2727  * The function is stateless, and does not change the AVCodecContext or the
2728  * device_ref AVHWDeviceContext.
2729  *
2730  * @param avctx The context which is currently calling get_format, and which
2731  * implicitly contains all state needed for filling the returned
2732  * AVHWFramesContext properly.
2733  * @param device_ref A reference to the AVHWDeviceContext describing the device
2734  * which will be used by the hardware decoder.
2735  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
2736  * @param out_frames_ref On success, set to a reference to an _uninitialized_
2737  * AVHWFramesContext, created from the given device_ref.
2738  * Fields will be set to values required for decoding.
2739  * Not changed if an error is returned.
2740  * @return zero on success, a negative value on error. The following error codes
2741  * have special semantics:
2742  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
2743  * is always manual, or it is a decoder which does not
2744  * support setting AVCodecContext.hw_frames_ctx at all,
2745  * or it is a software format.
2746  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
2747  * this configuration, or the device_ref is not supported
2748  * for the hwaccel referenced by hw_pix_fmt.
2749  */
2751  AVBufferRef *device_ref,
2753  AVBufferRef **out_frames_ref);
2754 
2755 
2756 
2757 /**
2758  * @defgroup lavc_parsing Frame parsing
2759  * @{
2760  */
2761 
2764  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
2765  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
2766  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
2767 };
2768 
2769 typedef struct AVCodecParserContext {
2770  void *priv_data;
2771  const struct AVCodecParser *parser;
2772  int64_t frame_offset; /* offset of the current frame */
2773  int64_t cur_offset; /* current offset
2774  (incremented by each av_parser_parse()) */
2775  int64_t next_frame_offset; /* offset of the next frame */
2776  /* video info */
2777  int pict_type; /* XXX: Put it back in AVCodecContext. */
2778  /**
2779  * This field is used for proper frame duration computation in lavf.
2780  * It signals, how much longer the frame duration of the current frame
2781  * is compared to normal frame duration.
2782  *
2783  * frame_duration = (1 + repeat_pict) * time_base
2784  *
2785  * It is used by codecs like H.264 to display telecined material.
2786  */
2787  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
2788  int64_t pts; /* pts of the current frame */
2789  int64_t dts; /* dts of the current frame */
2790 
2791  /* private data */
2792  int64_t last_pts;
2793  int64_t last_dts;
2795 
2796 #define AV_PARSER_PTS_NB 4
2801 
2802  int flags;
2803 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
2804 #define PARSER_FLAG_ONCE 0x0002
2805 /// Set if the parser has a valid file offset
2806 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
2807 #define PARSER_FLAG_USE_CODEC_TS 0x1000
2808 
2809  int64_t offset; ///< byte offset from starting packet start
2811 
2812  /**
2813  * Set by parser to 1 for key frames and 0 for non-key frames.
2814  * It is initialized to -1, so if the parser doesn't set this flag,
2815  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
2816  * will be used.
2817  */
2819 
2820  // Timestamp generation support:
2821  /**
2822  * Synchronization point for start of timestamp generation.
2823  *
2824  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
2825  * (default).
2826  *
2827  * For example, this corresponds to presence of H.264 buffering period
2828  * SEI message.
2829  */
2831 
2832  /**
2833  * Offset of the current timestamp against last timestamp sync point in
2834  * units of AVCodecContext.time_base.
2835  *
2836  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2837  * contain a valid timestamp offset.
2838  *
2839  * Note that the timestamp of sync point has usually a nonzero
2840  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
2841  * the next frame after timestamp sync point will be usually 1.
2842  *
2843  * For example, this corresponds to H.264 cpb_removal_delay.
2844  */
2846 
2847  /**
2848  * Presentation delay of current frame in units of AVCodecContext.time_base.
2849  *
2850  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2851  * contain valid non-negative timestamp delta (presentation time of a frame
2852  * must not lie in the past).
2853  *
2854  * This delay represents the difference between decoding and presentation
2855  * time of the frame.
2856  *
2857  * For example, this corresponds to H.264 dpb_output_delay.
2858  */
2860 
2861  /**
2862  * Position of the packet in file.
2863  *
2864  * Analogous to cur_frame_pts/dts
2865  */
2867 
2868  /**
2869  * Byte position of currently parsed frame in stream.
2870  */
2871  int64_t pos;
2872 
2873  /**
2874  * Previous frame byte position.
2875  */
2876  int64_t last_pos;
2877 
2878  /**
2879  * Duration of the current frame.
2880  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
2881  * For all other types, this is in units of AVCodecContext.time_base.
2882  */
2884 
2886 
2887  /**
2888  * Indicate whether a picture is coded as a frame, top field or bottom field.
2889  *
2890  * For example, H.264 field_pic_flag equal to 0 corresponds to
2891  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
2892  * equal to 1 and bottom_field_flag equal to 0 corresponds to
2893  * AV_PICTURE_STRUCTURE_TOP_FIELD.
2894  */
2896 
2897  /**
2898  * Picture number incremented in presentation or output order.
2899  * This field may be reinitialized at the first picture of a new sequence.
2900  *
2901  * For example, this corresponds to H.264 PicOrderCnt.
2902  */
2904 
2905  /**
2906  * Dimensions of the decoded video intended for presentation.
2907  */
2908  int width;
2909  int height;
2910 
2911  /**
2912  * Dimensions of the coded video.
2913  */
2916 
2917  /**
2918  * The format of the coded data, corresponds to enum AVPixelFormat for video
2919  * and for enum AVSampleFormat for audio.
2920  *
2921  * Note that a decoder can have considerable freedom in how exactly it
2922  * decodes the data, so the format reported here might be different from the
2923  * one returned by a decoder.
2924  */
2925  int format;
2927 
2928 typedef struct AVCodecParser {
2929  int codec_ids[5]; /* several codec IDs are permitted */
2932  /* This callback never returns an error, a negative value means that
2933  * the frame start was in a previous packet. */
2935  AVCodecContext *avctx,
2936  const uint8_t **poutbuf, int *poutbuf_size,
2937  const uint8_t *buf, int buf_size);
2939  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
2940 } AVCodecParser;
2941 
2942 /**
2943  * Iterate over all registered codec parsers.
2944  *
2945  * @param opaque a pointer where libavcodec will store the iteration state. Must
2946  * point to NULL to start the iteration.
2947  *
2948  * @return the next registered codec parser or NULL when the iteration is
2949  * finished
2950  */
2951 const AVCodecParser *av_parser_iterate(void **opaque);
2952 
2954 
2955 /**
2956  * Parse a packet.
2957  *
2958  * @param s parser context.
2959  * @param avctx codec context.
2960  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
2961  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
2962  * @param buf input buffer.
2963  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
2964  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
2965  To signal EOF, this should be 0 (so that the last frame
2966  can be output).
2967  * @param pts input presentation timestamp.
2968  * @param dts input decoding timestamp.
2969  * @param pos input byte position in stream.
2970  * @return the number of bytes of the input bitstream used.
2971  *
2972  * Example:
2973  * @code
2974  * while(in_len){
2975  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
2976  * in_data, in_len,
2977  * pts, dts, pos);
2978  * in_data += len;
2979  * in_len -= len;
2980  *
2981  * if(size)
2982  * decode_frame(data, size);
2983  * }
2984  * @endcode
2985  */
2987  AVCodecContext *avctx,
2988  uint8_t **poutbuf, int *poutbuf_size,
2989  const uint8_t *buf, int buf_size,
2990  int64_t pts, int64_t dts,
2991  int64_t pos);
2992 
2994 
2995 /**
2996  * @}
2997  * @}
2998  */
2999 
3000 /**
3001  * @addtogroup lavc_encoding
3002  * @{
3003  */
3004 
3005 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3006  const AVSubtitle *sub);
3007 
3008 
3009 /**
3010  * @}
3011  */
3012 
3013 /**
3014  * @defgroup lavc_misc Utility functions
3015  * @ingroup libavc
3016  *
3017  * Miscellaneous utility functions related to both encoding and decoding
3018  * (or neither).
3019  * @{
3020  */
3021 
3022 /**
3023  * @defgroup lavc_misc_pixfmt Pixel formats
3024  *
3025  * Functions for working with pixel formats.
3026  * @{
3027  */
3028 
3029 /**
3030  * Return a value representing the fourCC code associated to the
3031  * pixel format pix_fmt, or 0 if no associated fourCC code can be
3032  * found.
3033  */
3035 
3036 /**
3037  * Find the best pixel format to convert to given a certain source pixel
3038  * format. When converting from one pixel format to another, information loss
3039  * may occur. For example, when converting from RGB24 to GRAY, the color
3040  * information will be lost. Similarly, other losses occur when converting from
3041  * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
3042  * the given pixel formats should be used to suffer the least amount of loss.
3043  * The pixel formats from which it chooses one, are determined by the
3044  * pix_fmt_list parameter.
3045  *
3046  *
3047  * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
3048  * @param[in] src_pix_fmt source pixel format
3049  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
3050  * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
3051  * @return The best pixel format to convert to or -1 if none was found.
3052  */
3053 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
3054  enum AVPixelFormat src_pix_fmt,
3055  int has_alpha, int *loss_ptr);
3056 
3058 
3059 /**
3060  * @}
3061  */
3062 
3063 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
3064 
3065 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
3066 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
3067 //FIXME func typedef
3068 
3069 /**
3070  * Fill AVFrame audio data and linesize pointers.
3071  *
3072  * The buffer buf must be a preallocated buffer with a size big enough
3073  * to contain the specified samples amount. The filled AVFrame data
3074  * pointers will point to this buffer.
3075  *
3076  * AVFrame extended_data channel pointers are allocated if necessary for
3077  * planar audio.
3078  *
3079  * @param frame the AVFrame
3080  * frame->nb_samples must be set prior to calling the
3081  * function. This function fills in frame->data,
3082  * frame->extended_data, frame->linesize[0].
3083  * @param nb_channels channel count
3084  * @param sample_fmt sample format
3085  * @param buf buffer to use for frame data
3086  * @param buf_size size of buffer
3087  * @param align plane size sample alignment (0 = default)
3088  * @return >=0 on success, negative error code on failure
3089  * @todo return the size in bytes required to store the samples in
3090  * case of success, at the next libavutil bump
3091  */
3093  enum AVSampleFormat sample_fmt, const uint8_t *buf,
3094  int buf_size, int align);
3095 
3096 /**
3097  * Reset the internal codec state / flush internal buffers. Should be called
3098  * e.g. when seeking or when switching to a different stream.
3099  *
3100  * @note for decoders, this function just releases any references the decoder
3101  * might keep internally, but the caller's references remain valid.
3102  *
3103  * @note for encoders, this function will only do something if the encoder
3104  * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3105  * will drain any remaining packets, and can then be re-used for a different
3106  * stream (as opposed to sending a null frame which will leave the encoder
3107  * in a permanent EOF state after draining). This can be desirable if the
3108  * cost of tearing down and replacing the encoder instance is high.
3109  */
3111 
3112 /**
3113  * Return audio frame duration.
3114  *
3115  * @param avctx codec context
3116  * @param frame_bytes size of the frame, or 0 if unknown
3117  * @return frame duration, in samples, if known. 0 if not able to
3118  * determine.
3119  */
3120 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
3121 
3122 /* memory */
3123 
3124 /**
3125  * Same behaviour av_fast_malloc but the buffer has additional
3126  * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
3127  *
3128  * In addition the whole buffer will initially and after resizes
3129  * be 0-initialized so that no uninitialized data will ever appear.
3130  */
3131 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
3132 
3133 /**
3134  * Same behaviour av_fast_padded_malloc except that buffer will always
3135  * be 0-initialized after call.
3136  */
3137 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
3138 
3139 /**
3140  * @return a positive value if s is open (i.e. avcodec_open2() was called on it
3141  * with no corresponding avcodec_close()), 0 otherwise.
3142  */
3144 
3145 /**
3146  * @}
3147  */
3148 
3149 #endif /* AVCODEC_AVCODEC_H */
AVSubtitle
Definition: avcodec.h:2283
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:448
func
int(* func)(AVBPrint *dst, const char *in, const char *arg)
Definition: jacosubdec.c:68
avcodec_encode_subtitle
int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size, const AVSubtitle *sub)
Definition: encode.c:143
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1008
AVCodecContext::hwaccel
const struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:1355
AVCodec
AVCodec.
Definition: codec.h:197
AVCodecContext::hwaccel_context
void * hwaccel_context
Hardware accelerator context.
Definition: avcodec.h:1366
hw_pix_fmt
static enum AVPixelFormat hw_pix_fmt
Definition: hw_decode.c:46
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVCodecParserContext::pts
int64_t pts
Definition: avcodec.h:2788
AVCodecContext::log_level_offset
int log_level_offset
Definition: avcodec.h:385
AVCodecContext::keyint_min
int keyint_min
minimum GOP size
Definition: avcodec.h:921
avcodec_receive_packet
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:392
AVCodecContext::workaround_bugs
int workaround_bugs
Work around bugs in encoders which sometimes cannot be detected automatically.
Definition: avcodec.h:1247
AVSubtitle::rects
AVSubtitleRect ** rects
Definition: avcodec.h:2288
AVCodecContext::get_format
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Callback to negotiate the pixel format.
Definition: avcodec.h:643
AVCodecParserContext::dts_sync_point
int dts_sync_point
Synchronization point for start of timestamp generation.
Definition: avcodec.h:2830
AVCodecContext::audio_service_type
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:1053
AVCodecContext::channel_layout
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1039
AVCodecContext::colorspace
enum AVColorSpace colorspace
YUV colorspace type.
Definition: avcodec.h:956
AVColorTransferCharacteristic
AVColorTransferCharacteristic
Color Transfer Characteristic.
Definition: pixfmt.h:473
AVCodecContext::av_class
const AVClass * av_class
information on struct for av_log
Definition: avcodec.h:384
AVCodecParserContext::pict_type
int pict_type
Definition: avcodec.h:2777
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:988
AVCodecContext::rc_min_rate
int64_t rc_min_rate
minimum bitrate
Definition: avcodec.h:1197
AVCodecParserContext::output_picture_number
int output_picture_number
Picture number incremented in presentation or output order.
Definition: avcodec.h:2903
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
sub
static float sub(float src0, float src1)
Definition: dnn_backend_native_layer_mathbinary.c:31
AVHWAccel::type
enum AVMediaType type
Type of codec implemented by the hardware accelerator.
Definition: avcodec.h:2046
AV_PICTURE_STRUCTURE_UNKNOWN
@ AV_PICTURE_STRUCTURE_UNKNOWN
Definition: avcodec.h:2763
AVHWAccel::caps_internal
int caps_internal
Internal hwaccel capabilities.
Definition: avcodec.h:2182
avcodec_parameters_from_context
int avcodec_parameters_from_context(AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: codec_par.c:90
AVCodecParserContext::duration
int duration
Duration of the current frame.
Definition: avcodec.h:2883
AVCodecContext::err_recognition
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1320
avcodec_string
void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
Definition: avcodec.c:523
rational.h
AVCodecContext::coded_side_data
AVPacketSideData * coded_side_data
Additional data associated with the entire coded stream.
Definition: avcodec.h:1828
AVSubtitleRect
Definition: avcodec.h:2255
AVSubtitle::num_rects
unsigned num_rects
Definition: avcodec.h:2287
av_parser_iterate
const AVCodecParser * av_parser_iterate(void **opaque)
Iterate over all registered codec parsers.
Definition: parsers.c:78
AVCodecContext::intra_matrix
uint16_t * intra_matrix
custom intra quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:864
AVCodecContext::mv0_threshold
int mv0_threshold
Note: Value depends upon the compare function used for fullpel ME.
Definition: avcodec.h:935
AVCodecContext::lumi_masking
float lumi_masking
luminance masking (0-> disabled)
Definition: avcodec.h:698
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
AVCodecContext::color_trc
enum AVColorTransferCharacteristic color_trc
Color Transfer Characteristic.
Definition: avcodec.h:949
AVPacketSideData
Definition: packet.h:314
AVCodecParserContext::pts_dts_delta
int pts_dts_delta
Presentation delay of current frame in units of AVCodecContext.time_base.
Definition: avcodec.h:2859
AVCodecContext::slice_offset
int * slice_offset
slice offsets in the frame in bytes
Definition: avcodec.h:740
avcodec_decode_subtitle2
int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub, int *got_sub_ptr, AVPacket *avpkt)
Decode a subtitle message.
Definition: decode.c:802
AVCodecContext::field_order
enum AVFieldOrder field_order
Field order.
Definition: avcodec.h:985
AVHWAccel::capabilities
int capabilities
Hardware accelerated codec capabilities.
Definition: avcodec.h:2066
AVCodecContext::b_quant_offset
float b_quant_offset
qscale offset between IP and B-frames
Definition: avcodec.h:667
AVCodecParserContext::height
int height
Definition: avcodec.h:2909
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:330
RcOverride::qscale
int qscale
Definition: avcodec.h:193
AVHWAccel::init
int(* init)(AVCodecContext *avctx)
Initialize the hwaccel private data.
Definition: avcodec.h:2163
AVCodecContext::subtitle_header
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:1679
version.h
AVSubtitleRect::linesize
int linesize[4]
Definition: avcodec.h:2267
AVCodecParserContext::cur_frame_start_index
int cur_frame_start_index
Definition: avcodec.h:2797
AVCodecContext::me_pre_cmp
int me_pre_cmp
motion estimation prepass comparison function
Definition: avcodec.h:812
MpegEncContext::avctx
struct AVCodecContext * avctx
Definition: mpegvideo.h:98
AVDictionary
Definition: dict.c:30
AVColorPrimaries
AVColorPrimaries
Chromaticity coordinates of the source primaries.
Definition: pixfmt.h:448
avcodec_default_get_format
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: decode.c:871
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:852
avcodec_is_open
int avcodec_is_open(AVCodecContext *s)
Definition: avcodec.c:715
AVCodecContext::qmax
int qmax
maximum quantizer
Definition: avcodec.h:1161
AVCodecContext::request_channel_layout
uint64_t request_channel_layout
Request decoder to use this channel layout if it can (0 for default)
Definition: avcodec.h:1046
AVCodecParserContext::coded_width
int coded_width
Dimensions of the coded video.
Definition: avcodec.h:2914
AVCodecContext::delay
int delay
Codec delay.
Definition: avcodec.h:535
AVCodecContext::me_subpel_quality
int me_subpel_quality
subpel ME quality
Definition: avcodec.h:826
AVCodecContext::mb_cmp
int mb_cmp
macroblock comparison function (not supported yet)
Definition: avcodec.h:768
AVCodecContext::slice_count
int slice_count
slice count
Definition: avcodec.h:733
AVPictureStructure
AVPictureStructure
Definition: avcodec.h:2762
avcodec_pix_fmt_to_codec_tag
unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt)
Return a value representing the fourCC code associated to the pixel format pix_fmt,...
Definition: raw.c:305
SUBTITLE_ASS
@ SUBTITLE_ASS
Formatted text, the ass field must be set by the decoder and is authoritative.
Definition: avcodec.h:2250
AVCodecParserContext::parser
const struct AVCodecParser * parser
Definition: avcodec.h:2771
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:1706
AVCodecContext::skip_top
int skip_top
Number of macroblock rows at the top which are skipped.
Definition: avcodec.h:887
avcodec_enum_to_chroma_pos
int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos)
Converts AVChromaLocation to swscale x/y chroma position.
Definition: utils.c:345
AVCodecParserContext::offset
int64_t offset
byte offset from starting packet start
Definition: avcodec.h:2809
AVHWAccel
Definition: avcodec.h:2033
AVCodecParserContext::key_frame
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:2818
AVCodecContext::skip_idct
enum AVDiscard skip_idct
Skip IDCT/dequantization for selected frames.
Definition: avcodec.h:1662
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:684
AVCodecContext::nsse_weight
int nsse_weight
noise vs.
Definition: avcodec.h:1514
AVCodecContext::codec
const struct AVCodec * codec
Definition: avcodec.h:388
AVCodecContext::skip_frame
enum AVDiscard skip_frame
Skip decoding for selected frames.
Definition: avcodec.h:1669
AVCodecContext::thread_count
int thread_count
thread count is used to decide how many independent tasks should be passed to execute()
Definition: avcodec.h:1436
samplefmt.h
AVSubtitleRect::x
int x
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2256
AVCodecContext::initial_padding
int initial_padding
Audio only.
Definition: avcodec.h:1697
AVCodecContext::refs
int refs
number of reference frames
Definition: avcodec.h:928
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:459
AVCodecContext::bit_rate_tolerance
int bit_rate_tolerance
number of bits the bitstream is allowed to diverge from the reference.
Definition: avcodec.h:437
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:1380
av_parser_init
AVCodecParserContext * av_parser_init(int codec_id)
Definition: parser.c:34
pts
static int64_t pts
Definition: transcode_aac.c:653
AVCodecContext::coded_height
int coded_height
Definition: avcodec.h:567
AVCodecContext::max_samples
int64_t max_samples
The number of samples per frame to maximally accept.
Definition: avcodec.h:1968
codec.h
AVCodecParserContext::dts
int64_t dts
Definition: avcodec.h:2789
AVSubtitleRect::ass
char * ass
0 terminated ASS/SSA compatible event line.
Definition: avcodec.h:2278
AVHWAccel::priv_data_size
int priv_data_size
Size of the private data to allocate in AVCodecInternal.hwaccel_priv_data.
Definition: avcodec.h:2177
avsubtitle_free
void avsubtitle_free(AVSubtitle *sub)
Free all allocated data in the given subtitle struct.
Definition: avcodec.c:429
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:1143
AV_PICTURE_STRUCTURE_FRAME
@ AV_PICTURE_STRUCTURE_FRAME
Definition: avcodec.h:2766
RcOverride::quality_factor
float quality_factor
Definition: avcodec.h:194
AVCodecContext::color_primaries
enum AVColorPrimaries color_primaries
Chromaticity coordinates of the source primaries.
Definition: avcodec.h:942
AVCodecParserContext::cur_frame_end
int64_t cur_frame_end[AV_PARSER_PTS_NB]
Definition: avcodec.h:2810
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:1734
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:1218
codec_id.h
AVHWAccel::alloc_frame
int(* alloc_frame)(AVCodecContext *avctx, AVFrame *frame)
Allocate a custom buffer.
Definition: avcodec.h:2079
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:481
AVCodecContext::has_b_frames
int has_b_frames
Size of the frame reordering buffer in the decoder.
Definition: avcodec.h:675
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:141
width
#define width
AVCodecDescriptor
This struct describes the properties of a single codec described by an AVCodecID.
Definition: codec_desc.h:38
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVCodecContext::stats_in
char * stats_in
pass2 encoding statistics input buffer Concatenated stuff from stats_out of pass1 should be placed he...
Definition: avcodec.h:1240
AVCodecContext::global_quality
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:445
AVCodecParserContext::fetch_timestamp
int fetch_timestamp
Definition: avcodec.h:2794
AVHWAccel::uninit
int(* uninit)(AVCodecContext *avctx)
Uninitialize the hwaccel private data.
Definition: avcodec.h:2171
RcOverride
Definition: avcodec.h:190
AVCodecParserContext::last_pts
int64_t last_pts
Definition: avcodec.h:2792
AVSubtitleRect::y
int y
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2257
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:511
AVCodecContext::sub_text_format
int sub_text_format
Control the form of AVSubtitle.rects[N]->ass.
Definition: avcodec.h:1860
AVCodecContext::error_concealment
int error_concealment
error concealment flags
Definition: avcodec.h:1288
avcodec_receive_frame
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:639
AVSubtitleType
AVSubtitleType
Definition: avcodec.h:2235
AVCodecContext::thread_type
int thread_type
Which multithreading methods to use.
Definition: avcodec.h:1446
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1421
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:191
AVCodecParserContext::format
int format
The format of the coded data, corresponds to enum AVPixelFormat for video and for enum AVSampleFormat...
Definition: avcodec.h:2925
AVSubtitle::pts
int64_t pts
Same as packet pts, in AV_TIME_BASE.
Definition: avcodec.h:2289
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demuxing_decoding.c:41
avcodec_align_dimensions2
void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height, int linesize_align[AV_NUM_DATA_POINTERS])
Modify width and height values so that they will result in a memory buffer that is acceptable for the...
Definition: utils.c:136
AVCodecContext::max_pixels
int64_t max_pixels
The number of pixels per image to maximally accept.
Definition: avcodec.h:1880
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:369
AVHWAccel::decode_params
int(* decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size)
Callback for parameter data (SPS/PPS/VPS etc).
Definition: avcodec.h:2109
AVCodecContext::rc_max_rate
int64_t rc_max_rate
maximum bitrate
Definition: avcodec.h:1190
AVCodecContext::error
uint64_t error[AV_NUM_DATA_POINTERS]
error
Definition: avcodec.h:1373
AVSubtitleRect::text
char * text
0 terminated plain UTF-8 text
Definition: avcodec.h:2271
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:389
AVCodecContext::p_masking
float p_masking
p block masking (0-> disabled)
Definition: avcodec.h:719
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:2845
AVCodecParserContext::repeat_pict
int repeat_pict
This field is used for proper frame duration computation in lavf.
Definition: avcodec.h:2787
AV_PICTURE_STRUCTURE_BOTTOM_FIELD
@ AV_PICTURE_STRUCTURE_BOTTOM_FIELD
Definition: avcodec.h:2765
AVCodecContext::rc_buffer_size
int rc_buffer_size
decoder bitstream buffer size
Definition: avcodec.h:1175
AVCodecContext::sub_charenc
char * sub_charenc
DTS of the last frame.
Definition: avcodec.h:1744
AVSubtitleRect::w
int w
width of pict, undefined when pict is not set
Definition: avcodec.h:2258
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
avcodec_get_class
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:174
AVCodecContext::apply_cropping
int apply_cropping
Video decoding only.
Definition: avcodec.h:1938
AVCodecContext::color_range
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:963
AVCodecParser::codec_ids
int codec_ids[5]
Definition: avcodec.h:2929
AVCodecContext::slice_flags
int slice_flags
slice flags
Definition: avcodec.h:842
AVCodecParser::parser_close
void(* parser_close)(AVCodecParserContext *s)
Definition: avcodec.h:2938
avcodec_free_context
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
Definition: options.c:156
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVCodecContext::nb_coded_side_data
int nb_coded_side_data
Definition: avcodec.h:1829
AVCodecContext::qblur
float qblur
amount of qscale smoothing over time (0.0-1.0)
Definition: avcodec.h:1147
AV_PICTURE_STRUCTURE_TOP_FIELD
@ AV_PICTURE_STRUCTURE_TOP_FIELD
Definition: avcodec.h:2764
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:429
AVCodecParser::split
int(* split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
Definition: avcodec.h:2939
AVHWAccel::end_frame
int(* end_frame)(AVCodecContext *avctx)
Called at the end of each frame or field picture.
Definition: avcodec.h:2134
AVCodecContext::subtitle_header_size
int subtitle_header_size
Definition: avcodec.h:1680
AVSubtitleRect::data
uint8_t * data[4]
data+linesize for the bitmap of this subtitle.
Definition: avcodec.h:2266
src
#define src
Definition: vp8dsp.c:255
AVCodecContext::trailing_padding
int trailing_padding
Audio only.
Definition: avcodec.h:1872
AVCodecContext::ildct_cmp
int ildct_cmp
interlaced DCT comparison function
Definition: avcodec.h:774
avcodec_license
const char * avcodec_license(void)
Return the libavcodec license.
Definition: avcodec.c:61
AVCodecContext::thread_safe_callbacks
attribute_deprecated int thread_safe_callbacks
Set by the client if its custom get_buffer() callback can be called synchronously from another thread...
Definition: avcodec.h:1475
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:1211
avcodec_open2
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:137
AVCodecParserContext::flags
int flags
Definition: avcodec.h:2802
avcodec_version
unsigned avcodec_version(void)
Return the LIBAVCODEC_VERSION_INT constant.
Definition: avcodec.c:46
AVCodecContext::me_cmp
int me_cmp
motion estimation comparison function
Definition: avcodec.h:756
AVCodecParserContext::picture_structure
enum AVPictureStructure picture_structure
Indicate whether a picture is coded as a frame, top field or bottom field.
Definition: avcodec.h:2895
AVCodecContext::trellis
int trellis
trellis RD quantization
Definition: avcodec.h:1225
AVCodecContext::level
int level
level
Definition: avcodec.h:1647
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVAudioServiceType
AVAudioServiceType
Definition: defs.h:57
avcodec_get_subtitle_rect_class
const AVClass * avcodec_get_subtitle_rect_class(void)
Get the AVClass for AVSubtitleRect.
Definition: options.c:228
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:47
AVCodecContext::temporal_cplx_masking
float temporal_cplx_masking
temporary complexity masking (0-> disabled)
Definition: avcodec.h:705
AVCodecContext::qcompress
float qcompress
amount of qscale change between easy & hard scenes (0.0-1.0)
Definition: avcodec.h:1146
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:502
AVCodecContext::lowres
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:1428
options
const OptionDef options[]
AVCodecContext::stats_out
char * stats_out
pass1 encoding statistics output buffer
Definition: avcodec.h:1232
AVCodecContext::rc_override
RcOverride * rc_override
Definition: avcodec.h:1183
AVCodecContext::flags2
int flags2
AV_CODEC_FLAG2_*.
Definition: avcodec.h:466
AVMediaType
AVMediaType
Definition: avutil.h:199
AVCodecParserContext::frame_offset
int64_t frame_offset
Definition: avcodec.h:2772
AVCodecContext::gop_size
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:574
AVCodecContext::extra_hw_frames
int extra_hw_frames
Definition: avcodec.h:1952
AVCodecParserContext::next_frame_offset
int64_t next_frame_offset
Definition: avcodec.h:2775
AVCodecParserContext::cur_frame_offset
int64_t cur_frame_offset[AV_PARSER_PTS_NB]
Definition: avcodec.h:2798
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:996
AVCodecContext::pkt_timebase
AVRational pkt_timebase
Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
Definition: avcodec.h:1720
size
int size
Definition: twinvq_data.h:10344
AVCodecParserContext::width
int width
Dimensions of the decoded video intended for presentation.
Definition: avcodec.h:2908
AV_NUM_DATA_POINTERS
#define AV_NUM_DATA_POINTERS
Definition: frame.h:304
avcodec_get_frame_class
const attribute_deprecated AVClass * avcodec_get_frame_class(void)
Definition: options.c:202
AVCodecContext::me_range
int me_range
maximum motion estimation search range in subpel units If 0 then no limit.
Definition: avcodec.h:835
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:2934
AVCodecContext::skip_alpha
int skip_alpha
Skip processing alpha if supported by codec.
Definition: avcodec.h:1770
AVCodecContext::chroma_intra_matrix
uint16_t * chroma_intra_matrix
custom intra quantization matrix
Definition: avcodec.h:1795
AVCodecContext::skip_bottom
int skip_bottom
Number of macroblock rows at the bottom which are skipped.
Definition: avcodec.h:894
AVCodecContext::last_predictor_count
int last_predictor_count
amount of previous MV predictors (2a+1 x 2a+1 square)
Definition: avcodec.h:805
AVSubtitle::end_display_time
uint32_t end_display_time
Definition: avcodec.h:2286
frame.h
AVSubtitleRect::type
enum AVSubtitleType type
Definition: avcodec.h:2269
SUBTITLE_TEXT
@ SUBTITLE_TEXT
Plain text, the text field must be set by the decoder and is authoritative.
Definition: avcodec.h:2244
buffer.h
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
SUBTITLE_NONE
@ SUBTITLE_NONE
Definition: avcodec.h:2236
encode
static void encode(AVCodecContext *ctx, AVFrame *frame, AVPacket *pkt, FILE *output)
Definition: encode_audio.c:95
AVCodecContext::me_sub_cmp
int me_sub_cmp
subpixel motion estimation comparison function
Definition: avcodec.h:762
AVCodecContext::pts_correction_num_faulty_dts
int64_t pts_correction_num_faulty_dts
Number of incorrect PTS values so far.
Definition: avcodec.h:1735
height
#define height
AVCodecContext::pts_correction_last_pts
int64_t pts_correction_last_pts
Number of incorrect DTS values so far.
Definition: avcodec.h:1736
avcodec_default_execute
int avcodec_default_execute(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
Definition: avcodec.c:67
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
AVCodecContext::request_sample_fmt
enum AVSampleFormat request_sample_fmt
desired sample format
Definition: avcodec.h:1061
attributes.h
AVCodecInternal
Definition: internal.h:130
AVCodecContext::skip_loop_filter
enum AVDiscard skip_loop_filter
Skip loop filtering for selected frames.
Definition: avcodec.h:1655
SUBTITLE_BITMAP
@ SUBTITLE_BITMAP
A bitmap, pict will be set.
Definition: avcodec.h:2238
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:660
AVCodecParserContext::cur_frame_pts
int64_t cur_frame_pts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2799
AVCodecContext::channels
int channels
number of audio channels
Definition: avcodec.h:989
AVChromaLocation
AVChromaLocation
Location of chroma samples.
Definition: pixfmt.h:595
AVCodecParserContext::cur_frame_pos
int64_t cur_frame_pos[AV_PARSER_PTS_NB]
Position of the packet in file.
Definition: avcodec.h:2866
AVHWAccel::name
const char * name
Name of the hardware accelerated codec.
Definition: avcodec.h:2039
AVSubtitleRect::flags
int flags
Definition: avcodec.h:2280
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1414
avcodec_default_get_buffer2
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags)
The default callback for AVCodecContext.get_buffer2().
Definition: decode.c:1449
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:576
AVCodecParserContext::pos
int64_t pos
Byte position of currently parsed frame in stream.
Definition: avcodec.h:2871
AVSubtitle::format
uint16_t format
Definition: avcodec.h:2284
log.h
RcOverride::end_frame
int end_frame
Definition: avcodec.h:192
AVCodecContext::properties
unsigned properties
Properties of the stream that gets decoded.
Definition: avcodec.h:1818
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:480
AVSubtitleRect::nb_colors
int nb_colors
number of colors in pict, undefined when pict is not set
Definition: avcodec.h:2260
AVHWAccel::decode_slice
int(* decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size)
Callback for each slice.
Definition: avcodec.h:2123
packet.h
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: codec_par.c:147
AVCodecContext::intra_dc_precision
int intra_dc_precision
precision of the intra DC coefficient - 8
Definition: avcodec.h:880
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:502
AVCodecContext::cutoff
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1032
AVCodecContext::hwaccel_flags
int hwaccel_flags
Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated decoding (if active).
Definition: avcodec.h:1911
AVCodecParserContext::cur_offset
int64_t cur_offset
Definition: avcodec.h:2773
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
av_fast_padded_malloc
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_malloc but the buffer has additional AV_INPUT_BUFFER_PADDING_SIZE at the end w...
Definition: utils.c:50
AVCodecParser::parser_init
int(* parser_init)(AVCodecParserContext *s)
Definition: avcodec.h:2931
AVCodecContext::pts_correction_last_dts
int64_t pts_correction_last_dts
PTS of the last frame.
Definition: avcodec.h:1737
AVCodecContext::dia_size
int dia_size
ME diamond size & shape.
Definition: avcodec.h:798
AVCodecContext::dump_separator
uint8_t * dump_separator
dump format separator.
Definition: avcodec.h:1803
AVCodecContext::mb_lmin
int mb_lmin
minimum MB Lagrange multiplier
Definition: avcodec.h:901
av_get_audio_frame_duration
int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
Return audio frame duration.
Definition: utils.c:811
AVCodecContext::idct_algo
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:1393
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:1902
AVCodecContext::chroma_sample_location
enum AVChromaLocation chroma_sample_location
This defines the location of chroma samples.
Definition: avcodec.h:970
AVCodecContext::height
int height
Definition: avcodec.h:552
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:361
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:589
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:1853
AVCodecParserContext
Definition: avcodec.h:2769
AVCodecContext::sub_charenc_mode
int sub_charenc_mode
Subtitles character encoding mode.
Definition: avcodec.h:1752
AVHWAccel::decode_mb
void(* decode_mb)(struct MpegEncContext *s)
Called for every Macroblock in a slice.
Definition: avcodec.h:2154
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:985
ret
ret
Definition: filter_design.txt:187
AVSubtitleRect::h
int h
height of pict, undefined when pict is not set
Definition: avcodec.h:2259
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:1025
pixfmt.h
avcodec_flush_buffers
void avcodec_flush_buffers(AVCodecContext *avctx)
Reset the internal codec state / flush internal buffers.
Definition: avcodec.c:380
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
AVCodecParserContext::coded_height
int coded_height
Definition: avcodec.h:2915
AVCodecContext::strict_std_compliance
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1276
AVCodecContext::opaque
void * opaque
Private data of the user, can be used to carry app specific stuff.
Definition: avcodec.h:421
pos
unsigned int pos
Definition: spdifenc.c:412
AVCodecParser::priv_data_size
int priv_data_size
Definition: avcodec.h:2930
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:614
AVCodecContext::max_qdiff
int max_qdiff
maximum quantizer difference between frames
Definition: avcodec.h:1168
AVCodecContext::dark_masking
float dark_masking
darkness masking (0-> disabled)
Definition: avcodec.h:726
AVCodecContext
main external API structure.
Definition: avcodec.h:379
AVCodecContext::active_thread_type
int active_thread_type
Which multithreading methods are in use by the codec.
Definition: avcodec.h:1455
AVCodecContext::codec_descriptor
const AVCodecDescriptor * codec_descriptor
AVCodecDescriptor.
Definition: avcodec.h:1727
c2
static const uint64_t c2
Definition: murmur3.c:52
AVCodecParserContext::field_order
enum AVFieldOrder field_order
Definition: avcodec.h:2885
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:1487
AVCodecContext::qmin
int qmin
minimum quantizer
Definition: avcodec.h:1154
AVHWAccel::frame_priv_data_size
int frame_priv_data_size
Size of per-frame hardware accelerator private data.
Definition: avcodec.h:2143
AVCodecContext::bidir_refine
int bidir_refine
Definition: avcodec.h:914
AVCodecContext::profile
int profile
profile
Definition: avcodec.h:1521
defs.h
av_fast_padded_mallocz
void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_padded_malloc except that buffer will always be 0-initialized after call.
Definition: utils.c:63
AVCodecContext::get_encode_buffer
int(* get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags)
This callback is called at the beginning of each packet to get a data buffer for it.
Definition: avcodec.h:2020
AVCodecContext::spatial_cplx_masking
float spatial_cplx_masking
spatial complexity masking (0-> disabled)
Definition: avcodec.h:712
AVCodecContext::i_quant_offset
float i_quant_offset
qscale offset between P and I-frames
Definition: avcodec.h:691
AVCodecContext::discard_damaged_percentage
int discard_damaged_percentage
The percentage of damaged samples to discard a frame.
Definition: avcodec.h:1960
AVCodecContext::mb_lmax
int mb_lmax
maximum MB Lagrange multiplier
Definition: avcodec.h:908
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:1978
avcodec_chroma_pos_to_enum
enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos)
Converts swscale x/y chroma position to AVChromaLocation.
Definition: utils.c:357
AVCodecContext::pre_dia_size
int pre_dia_size
ME prepass diamond size & shape.
Definition: avcodec.h:819
AVCodecContext::debug
int debug
debug
Definition: avcodec.h:1298
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:2095
AVCodecContext::coded_width
int coded_width
Bitstream width / height, may be different from width/height e.g.
Definition: avcodec.h:567
AVCodecContext::codec_type
enum AVMediaType codec_type
Definition: avcodec.h:387
AVCodecContext::seek_preroll
int seek_preroll
Number of samples to skip after a discontinuity.
Definition: avcodec.h:1777
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:651
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:1019
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:1204
AVCodecContext::codec_tag
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:404
codec_par.h
AVFieldOrder
AVFieldOrder
Definition: codec_par.h:36
AV_PARSER_PTS_NB
#define AV_PARSER_PTS_NB
Definition: avcodec.h:2796
AVCodecContext::slices
int slices
Number of slices.
Definition: avcodec.h:979
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:406
avcodec_default_get_encode_buffer
int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags)
The default callback for AVCodecContext.get_encode_buffer().
Definition: encode.c:56
AVCodecParserContext::last_pos
int64_t last_pos
Previous frame byte position.
Definition: avcodec.h:2876
AVCodecContext::inter_matrix
uint16_t * inter_matrix
custom inter quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:873
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:2192
AVCodecParser
Definition: avcodec.h:2928
AVCodecContext::rc_override_count
int rc_override_count
ratecontrol override, see RcOverride
Definition: avcodec.h:1182
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:1348
avcodec_configuration
const char * avcodec_configuration(void)
Return the libavcodec build-time configuration.
Definition: avcodec.c:56
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:552
AVCodecContext::debug_mv
attribute_deprecated int debug_mv
Definition: avcodec.h:1784
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParserContext::priv_data
void * priv_data
Definition: avcodec.h:2770
AVCodecContext::sw_pix_fmt
enum AVPixelFormat sw_pix_fmt
Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1713
AVCodecParserContext::cur_frame_dts
int64_t cur_frame_dts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2800
AVCodecContext::codec_whitelist
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avcodec.h:1811
AVDiscard
AVDiscard
Definition: defs.h:45
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:541
AVCodecParserContext::last_dts
int64_t last_dts
Definition: avcodec.h:2793
codec_desc.h
int
int
Definition: ffmpeg_filter.c:156
MpegEncContext
MpegEncContext.
Definition: mpegvideo.h:81
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:1507
AVHWAccel::pix_fmt
enum AVPixelFormat pix_fmt
Supported pixel format.
Definition: avcodec.h:2060
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:749
AVSubtitle::start_display_time
uint32_t start_display_time
Definition: avcodec.h:2285
AVCodecContext::compression_level
int compression_level
Definition: avcodec.h:451
av_parser_close
void av_parser_close(AVCodecParserContext *s)
Definition: parser.c:187
nb_channels
int nb_channels
Definition: channel_layout.c:81
AVHWAccel::id
enum AVCodecID id
Codec implemented by the hardware accelerator.
Definition: avcodec.h:2053