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/channel_layout.h"
35#include "libavutil/dict.h"
36#include "libavutil/frame.h"
37#include "libavutil/log.h"
38#include "libavutil/pixfmt.h"
39#include "libavutil/rational.h"
40
41#include "codec.h"
42#include "codec_id.h"
43#include "defs.h"
44#include "packet.h"
45#include "version_major.h"
46#ifndef HAVE_AV_CONFIG_H
47/* When included as part of the ffmpeg build, only include the major version
48 * to avoid unnecessary rebuilds. When included externally, keep including
49 * the full version information. */
50#include "version.h"
51
52#include "codec_desc.h"
53#include "codec_par.h"
54#endif
55
56struct AVCodecParameters;
57
58/**
59 * @defgroup libavc libavcodec
60 * Encoding/Decoding Library
61 *
62 * @{
63 *
64 * @defgroup lavc_decoding Decoding
65 * @{
66 * @}
67 *
68 * @defgroup lavc_encoding Encoding
69 * @{
70 * @}
71 *
72 * @defgroup lavc_codec Codecs
73 * @{
74 * @defgroup lavc_codec_native Native Codecs
75 * @{
76 * @}
77 * @defgroup lavc_codec_wrappers External library wrappers
78 * @{
79 * @}
80 * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
81 * @{
82 * @}
83 * @}
84 * @defgroup lavc_internal Internal
85 * @{
86 * @}
87 * @}
88 */
89
90/**
91 * @ingroup libavc
92 * @defgroup lavc_encdec send/receive encoding and decoding API overview
93 * @{
94 *
95 * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
96 * avcodec_receive_packet() functions provide an encode/decode API, which
97 * decouples input and output.
98 *
99 * The API is very similar for encoding/decoding and audio/video, and works as
100 * follows:
101 * - Set up and open the AVCodecContext as usual.
102 * - Send valid input:
103 * - For decoding, call avcodec_send_packet() to give the decoder raw
104 * compressed data in an AVPacket.
105 * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
106 * containing uncompressed audio or video.
107 *
108 * In both cases, it is recommended that AVPackets and AVFrames are
109 * refcounted, or libavcodec might have to copy the input data. (libavformat
110 * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
111 * refcounted AVFrames.)
112 * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
113 * functions and process their output:
114 * - For decoding, call avcodec_receive_frame(). On success, it will return
115 * an AVFrame containing uncompressed audio or video data.
116 * - For encoding, call avcodec_receive_packet(). On success, it will return
117 * an AVPacket with a compressed frame.
118 *
119 * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
120 * AVERROR(EAGAIN) return value means that new input data is required to
121 * return new output. In this case, continue with sending input. For each
122 * input frame/packet, the codec will typically return 1 output frame/packet,
123 * but it can also be 0 or more than 1.
124 *
125 * At the beginning of decoding or encoding, the codec might accept multiple
126 * input frames/packets without returning a frame, until its internal buffers
127 * are filled. This situation is handled transparently if you follow the steps
128 * outlined above.
129 *
130 * In theory, sending input can result in EAGAIN - this should happen only if
131 * not all output was received. You can use this to structure alternative decode
132 * or encode loops other than the one suggested above. For example, you could
133 * try sending new input on each iteration, and try to receive output if that
134 * returns EAGAIN.
135 *
136 * End of stream situations. These require "flushing" (aka draining) the codec,
137 * as the codec might buffer multiple frames or packets internally for
138 * performance or out of necessity (consider B-frames).
139 * This is handled as follows:
140 * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
141 * or avcodec_send_frame() (encoding) functions. This will enter draining
142 * mode.
143 * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
144 * (encoding) in a loop until AVERROR_EOF is returned. The functions will
145 * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
146 * - Before decoding can be resumed again, the codec has to be reset with
147 * avcodec_flush_buffers().
148 *
149 * Using the API as outlined above is highly recommended. But it is also
150 * possible to call functions outside of this rigid schema. For example, you can
151 * call avcodec_send_packet() repeatedly without calling
152 * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
153 * until the codec's internal buffer has been filled up (which is typically of
154 * size 1 per output frame, after initial input), and then reject input with
155 * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
156 * read at least some output.
157 *
158 * Not all codecs will follow a rigid and predictable dataflow; the only
159 * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
160 * one end implies that a receive/send call on the other end will succeed, or
161 * at least will not fail with AVERROR(EAGAIN). In general, no codec will
162 * permit unlimited buffering of input or output.
163 *
164 * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
165 * would be an invalid state, which could put the codec user into an endless
166 * loop. The API has no concept of time either: it cannot happen that trying to
167 * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
168 * later accepts the packet (with no other receive/flush API calls involved).
169 * The API is a strict state machine, and the passage of time is not supposed
170 * to influence it. Some timing-dependent behavior might still be deemed
171 * acceptable in certain cases. But it must never result in both send/receive
172 * returning EAGAIN at the same time at any point. It must also absolutely be
173 * avoided that the current state is "unstable" and can "flip-flop" between
174 * the send/receive APIs allowing progress. For example, it's not allowed that
175 * the codec randomly decides that it actually wants to consume a packet now
176 * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
177 * avcodec_send_packet() call.
178 * @}
179 */
180
181/**
182 * @defgroup lavc_core Core functions/structures.
183 * @ingroup libavc
184 *
185 * Basic definitions, functions for querying libavcodec capabilities,
186 * allocating core structures, etc.
187 * @{
188 */
189
190/**
191 * @ingroup lavc_encoding
192 * minimum encoding buffer size
193 * Used to avoid some checks during header writing.
194 */
195#define AV_INPUT_BUFFER_MIN_SIZE 16384
196
197/**
198 * @ingroup lavc_encoding
199 */
200typedef struct RcOverride{
201 int start_frame;
202 int end_frame;
203 int qscale; // If this is 0 then quality_factor will be used instead.
204 float quality_factor;
205} RcOverride;
206
207/* encoding support
208 These flags can be passed in AVCodecContext.flags before initialization.
209 Note: Not everything is supported yet.
210*/
211
212/**
213 * Allow decoders to produce frames with data planes that are not aligned
214 * to CPU requirements (e.g. due to cropping).
215 */
216#define AV_CODEC_FLAG_UNALIGNED (1 << 0)
217/**
218 * Use fixed qscale.
219 */
220#define AV_CODEC_FLAG_QSCALE (1 << 1)
221/**
222 * 4 MV per MB allowed / advanced prediction for H.263.
223 */
224#define AV_CODEC_FLAG_4MV (1 << 2)
225/**
226 * Output even those frames that might be corrupted.
227 */
228#define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
229/**
230 * Use qpel MC.
231 */
232#define AV_CODEC_FLAG_QPEL (1 << 4)
233#if FF_API_DROPCHANGED
234/**
235 * Don't output frames whose parameters differ from first
236 * decoded frame in stream.
237 *
238 * @deprecated callers should implement this functionality in their own code
239 */
240#define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
241#endif
242/**
243 * Request the encoder to output reconstructed frames, i.e.\ frames that would
244 * be produced by decoding the encoded bistream. These frames may be retrieved
245 * by calling avcodec_receive_frame() immediately after a successful call to
246 * avcodec_receive_packet().
247 *
248 * Should only be used with encoders flagged with the
249 * @ref AV_CODEC_CAP_ENCODER_RECON_FRAME capability.
250 *
251 * @note
252 * Each reconstructed frame returned by the encoder corresponds to the last
253 * encoded packet, i.e. the frames are returned in coded order rather than
254 * presentation order.
255 *
256 * @note
257 * Frame parameters (like pixel format or dimensions) do not have to match the
258 * AVCodecContext values. Make sure to use the values from the returned frame.
259 */
260#define AV_CODEC_FLAG_RECON_FRAME (1 << 6)
261/**
262 * @par decoding
263 * Request the decoder to propagate each packet's AVPacket.opaque and
264 * AVPacket.opaque_ref to its corresponding output AVFrame.
265 *
266 * @par encoding:
267 * Request the encoder to propagate each frame's AVFrame.opaque and
268 * AVFrame.opaque_ref values to its corresponding output AVPacket.
269 *
270 * @par
271 * May only be set on encoders that have the
272 * @ref AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability flag.
273 *
274 * @note
275 * While in typical cases one input frame produces exactly one output packet
276 * (perhaps after a delay), in general the mapping of frames to packets is
277 * M-to-N, so
278 * - Any number of input frames may be associated with any given output packet.
279 * This includes zero - e.g. some encoders may output packets that carry only
280 * metadata about the whole stream.
281 * - A given input frame may be associated with any number of output packets.
282 * Again this includes zero - e.g. some encoders may drop frames under certain
283 * conditions.
284 * .
285 * This implies that when using this flag, the caller must NOT assume that
286 * - a given input frame's opaques will necessarily appear on some output packet;
287 * - every output packet will have some non-NULL opaque value.
288 * .
289 * When an output packet contains multiple frames, the opaque values will be
290 * taken from the first of those.
291 *
292 * @note
293 * The converse holds for decoders, with frames and packets switched.
294 */
295#define AV_CODEC_FLAG_COPY_OPAQUE (1 << 7)
296/**
297 * Signal to the encoder that the values of AVFrame.duration are valid and
298 * should be used (typically for transferring them to output packets).
299 *
300 * If this flag is not set, frame durations are ignored.
301 */
302#define AV_CODEC_FLAG_FRAME_DURATION (1 << 8)
303/**
304 * Use internal 2pass ratecontrol in first pass mode.
305 */
306#define AV_CODEC_FLAG_PASS1 (1 << 9)
307/**
308 * Use internal 2pass ratecontrol in second pass mode.
309 */
310#define AV_CODEC_FLAG_PASS2 (1 << 10)
311/**
312 * loop filter.
313 */
314#define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
315/**
316 * Only decode/encode grayscale.
317 */
318#define AV_CODEC_FLAG_GRAY (1 << 13)
319/**
320 * error[?] variables will be set during encoding.
321 */
322#define AV_CODEC_FLAG_PSNR (1 << 15)
323/**
324 * Use interlaced DCT.
325 */
326#define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
327/**
328 * Force low delay.
329 */
330#define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
331/**
332 * Place global headers in extradata instead of every keyframe.
333 */
334#define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
335/**
336 * Use only bitexact stuff (except (I)DCT).
337 */
338#define AV_CODEC_FLAG_BITEXACT (1 << 23)
339/* Fx : Flag for H.263+ extra options */
340/**
341 * H.263 advanced intra coding / MPEG-4 AC prediction
342 */
343#define AV_CODEC_FLAG_AC_PRED (1 << 24)
344/**
345 * interlaced motion estimation
346 */
347#define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
348#define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
349
350/**
351 * Allow non spec compliant speedup tricks.
352 */
353#define AV_CODEC_FLAG2_FAST (1 << 0)
354/**
355 * Skip bitstream encoding.
356 */
357#define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
358/**
359 * Place global headers at every keyframe instead of in extradata.
360 */
361#define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
362
363/**
364 * Input bitstream might be truncated at a packet boundaries
365 * instead of only at frame boundaries.
366 */
367#define AV_CODEC_FLAG2_CHUNKS (1 << 15)
368/**
369 * Discard cropping information from SPS.
370 */
371#define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
372
373/**
374 * Show all frames before the first keyframe
375 */
376#define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
377/**
378 * Export motion vectors through frame side data
379 */
380#define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
381/**
382 * Do not skip samples and export skip information as frame side data
383 */
384#define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
385/**
386 * Do not reset ASS ReadOrder field on flush (subtitles decoding)
387 */
388#define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
389/**
390 * Generate/parse ICC profiles on encode/decode, as appropriate for the type of
391 * file. No effect on codecs which cannot contain embedded ICC profiles, or
392 * when compiled without support for lcms2.
393 */
394#define AV_CODEC_FLAG2_ICC_PROFILES (1U << 31)
395
396/* Exported side data.
397 These flags can be passed in AVCodecContext.export_side_data before initialization.
398*/
399/**
400 * Export motion vectors through frame side data
401 */
402#define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
403/**
404 * Export encoder Producer Reference Time through packet side data
405 */
406#define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
407/**
408 * Decoding only.
409 * Export the AVVideoEncParams structure through frame side data.
410 */
411#define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
412/**
413 * Decoding only.
414 * Do not apply film grain, export it instead.
415 */
416#define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
417
418/**
419 * The decoder will keep a reference to the frame and may reuse it later.
420 */
421#define AV_GET_BUFFER_FLAG_REF (1 << 0)
422
423/**
424 * The encoder will keep a reference to the packet and may reuse it later.
425 */
426#define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
427
428/**
429 * main external API structure.
430 * New fields can be added to the end with minor version bumps.
431 * Removal, reordering and changes to existing fields require a major
432 * version bump.
433 * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
434 * applications.
435 * The name string for AVOptions options matches the associated command line
436 * parameter name and can be found in libavcodec/options_table.h
437 * The AVOption/command line parameter names differ in some cases from the C
438 * structure field names for historic reasons or brevity.
439 * sizeof(AVCodecContext) must not be used outside libav*.
440 */
441typedef struct AVCodecContext {
442 /**
443 * information on struct for av_log
444 * - set by avcodec_alloc_context3
445 */
446 const AVClass *av_class;
447 int log_level_offset;
448
449 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
450 const struct AVCodec *codec;
451 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
452
453 /**
454 * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
455 * This is used to work around some encoder bugs.
456 * A demuxer should set this to what is stored in the field used to identify the codec.
457 * If there are multiple such fields in a container then the demuxer should choose the one
458 * which maximizes the information about the used codec.
459 * If the codec tag field in a container is larger than 32 bits then the demuxer should
460 * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
461 * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
462 * first.
463 * - encoding: Set by user, if not then the default based on codec_id will be used.
464 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
465 */
466 unsigned int codec_tag;
467
468 void *priv_data;
469
470 /**
471 * Private context used for internal data.
472 *
473 * Unlike priv_data, this is not codec-specific. It is used in general
474 * libavcodec functions.
475 */
476 struct AVCodecInternal *internal;
477
478 /**
479 * Private data of the user, can be used to carry app specific stuff.
480 * - encoding: Set by user.
481 * - decoding: Set by user.
482 */
483 void *opaque;
484
485 /**
486 * the average bitrate
487 * - encoding: Set by user; unused for constant quantizer encoding.
488 * - decoding: Set by user, may be overwritten by libavcodec
489 * if this info is available in the stream
490 */
491 int64_t bit_rate;
492
493 /**
494 * number of bits the bitstream is allowed to diverge from the reference.
495 * the reference can be CBR (for CBR pass1) or VBR (for pass2)
496 * - encoding: Set by user; unused for constant quantizer encoding.
497 * - decoding: unused
498 */
499 int bit_rate_tolerance;
500
501 /**
502 * Global quality for codecs which cannot change it per frame.
503 * This should be proportional to MPEG-1/2/4 qscale.
504 * - encoding: Set by user.
505 * - decoding: unused
506 */
507 int global_quality;
508
509 /**
510 * - encoding: Set by user.
511 * - decoding: unused
512 */
513 int compression_level;
514#define FF_COMPRESSION_DEFAULT -1
515
516 /**
517 * AV_CODEC_FLAG_*.
518 * - encoding: Set by user.
519 * - decoding: Set by user.
520 */
521 int flags;
522
523 /**
524 * AV_CODEC_FLAG2_*
525 * - encoding: Set by user.
526 * - decoding: Set by user.
527 */
528 int flags2;
529
530 /**
531 * some codecs need / can use extradata like Huffman tables.
532 * MJPEG: Huffman tables
533 * rv10: additional flags
534 * MPEG-4: global headers (they can be in the bitstream or here)
535 * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
536 * than extradata_size to avoid problems if it is read with the bitstream reader.
537 * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
538 * Must be allocated with the av_malloc() family of functions.
539 * - encoding: Set/allocated/freed by libavcodec.
540 * - decoding: Set/allocated/freed by user.
541 */
542 uint8_t *extradata;
543 int extradata_size;
544
545 /**
546 * This is the fundamental unit of time (in seconds) in terms
547 * of which frame timestamps are represented. For fixed-fps content,
548 * timebase should be 1/framerate and timestamp increments should be
549 * identically 1.
550 * This often, but not always is the inverse of the frame rate or field rate
551 * for video. 1/time_base is not the average frame rate if the frame rate is not
552 * constant.
553 *
554 * Like containers, elementary streams also can store timestamps, 1/time_base
555 * is the unit in which these timestamps are specified.
556 * As example of such codec time base see ISO/IEC 14496-2:2001(E)
557 * vop_time_increment_resolution and fixed_vop_rate
558 * (fixed_vop_rate == 0 implies that it is different from the framerate)
559 *
560 * - encoding: MUST be set by user.
561 * - decoding: unused.
562 */
563 AVRational time_base;
564
565#if FF_API_TICKS_PER_FRAME
566 /**
567 * For some codecs, the time base is closer to the field rate than the frame rate.
568 * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
569 * if no telecine is used ...
570 *
571 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
572 *
573 * @deprecated
574 * - decoding: Use AVCodecDescriptor.props & AV_CODEC_PROP_FIELDS
575 * - encoding: Set AVCodecContext.framerate instead
576 *
577 */
578 attribute_deprecated
579 int ticks_per_frame;
580#endif
581
582 /**
583 * Codec delay.
584 *
585 * Encoding: Number of frames delay there will be from the encoder input to
586 * the decoder output. (we assume the decoder matches the spec)
587 * Decoding: Number of frames delay in addition to what a standard decoder
588 * as specified in the spec would produce.
589 *
590 * Video:
591 * Number of frames the decoded output will be delayed relative to the
592 * encoded input.
593 *
594 * Audio:
595 * For encoding, this field is unused (see initial_padding).
596 *
597 * For decoding, this is the number of samples the decoder needs to
598 * output before the decoder's output is valid. When seeking, you should
599 * start decoding this many samples prior to your desired seek point.
600 *
601 * - encoding: Set by libavcodec.
602 * - decoding: Set by libavcodec.
603 */
604 int delay;
605
606
607 /* video only */
608 /**
609 * picture width / height.
610 *
611 * @note Those fields may not match the values of the last
612 * AVFrame output by avcodec_receive_frame() due frame
613 * reordering.
614 *
615 * - encoding: MUST be set by user.
616 * - decoding: May be set by the user before opening the decoder if known e.g.
617 * from the container. Some decoders will require the dimensions
618 * to be set by the caller. During decoding, the decoder may
619 * overwrite those values as required while parsing the data.
620 */
621 int width, height;
622
623 /**
624 * Bitstream width / height, may be different from width/height e.g. when
625 * the decoded frame is cropped before being output or lowres is enabled.
626 *
627 * @note Those field may not match the value of the last
628 * AVFrame output by avcodec_receive_frame() due frame
629 * reordering.
630 *
631 * - encoding: unused
632 * - decoding: May be set by the user before opening the decoder if known
633 * e.g. from the container. During decoding, the decoder may
634 * overwrite those values as required while parsing the data.
635 */
636 int coded_width, coded_height;
637
638 /**
639 * the number of pictures in a group of pictures, or 0 for intra_only
640 * - encoding: Set by user.
641 * - decoding: unused
642 */
643 int gop_size;
644
645 /**
646 * Pixel format, see AV_PIX_FMT_xxx.
647 * May be set by the demuxer if known from headers.
648 * May be overridden by the decoder if it knows better.
649 *
650 * @note This field may not match the value of the last
651 * AVFrame output by avcodec_receive_frame() due frame
652 * reordering.
653 *
654 * - encoding: Set by user.
655 * - decoding: Set by user if known, overridden by libavcodec while
656 * parsing the data.
657 */
658 enum AVPixelFormat pix_fmt;
659
660 /**
661 * If non NULL, 'draw_horiz_band' is called by the libavcodec
662 * decoder to draw a horizontal band. It improves cache usage. Not
663 * all codecs can do that. You must check the codec capabilities
664 * beforehand.
665 * When multithreading is used, it may be called from multiple threads
666 * at the same time; threads might draw different parts of the same AVFrame,
667 * or multiple AVFrames, and there is no guarantee that slices will be drawn
668 * in order.
669 * The function is also used by hardware acceleration APIs.
670 * It is called at least once during frame decoding to pass
671 * the data needed for hardware render.
672 * In that mode instead of pixel data, AVFrame points to
673 * a structure specific to the acceleration API. The application
674 * reads the structure and can change some fields to indicate progress
675 * or mark state.
676 * - encoding: unused
677 * - decoding: Set by user.
678 * @param height the height of the slice
679 * @param y the y position of the slice
680 * @param type 1->top field, 2->bottom field, 3->frame
681 * @param offset offset into the AVFrame.data from which the slice should be read
682 */
683 void (*draw_horiz_band)(struct AVCodecContext *s,
684 const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
685 int y, int type, int height);
686
687 /**
688 * Callback to negotiate the pixel format. Decoding only, may be set by the
689 * caller before avcodec_open2().
690 *
691 * Called by some decoders to select the pixel format that will be used for
692 * the output frames. This is mainly used to set up hardware acceleration,
693 * then the provided format list contains the corresponding hwaccel pixel
694 * formats alongside the "software" one. The software pixel format may also
695 * be retrieved from \ref sw_pix_fmt.
696 *
697 * This callback will be called when the coded frame properties (such as
698 * resolution, pixel format, etc.) change and more than one output format is
699 * supported for those new properties. If a hardware pixel format is chosen
700 * and initialization for it fails, the callback may be called again
701 * immediately.
702 *
703 * This callback may be called from different threads if the decoder is
704 * multi-threaded, but not from more than one thread simultaneously.
705 *
706 * @param fmt list of formats which may be used in the current
707 * configuration, terminated by AV_PIX_FMT_NONE.
708 * @warning Behavior is undefined if the callback returns a value other
709 * than one of the formats in fmt or AV_PIX_FMT_NONE.
710 * @return the chosen format or AV_PIX_FMT_NONE
711 */
712 enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
713
714 /**
715 * maximum number of B-frames between non-B-frames
716 * Note: The output will be delayed by max_b_frames+1 relative to the input.
717 * - encoding: Set by user.
718 * - decoding: unused
719 */
720 int max_b_frames;
721
722 /**
723 * qscale factor between IP and B-frames
724 * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
725 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
726 * - encoding: Set by user.
727 * - decoding: unused
728 */
729 float b_quant_factor;
730
731 /**
732 * qscale offset between IP and B-frames
733 * - encoding: Set by user.
734 * - decoding: unused
735 */
736 float b_quant_offset;
737
738 /**
739 * Size of the frame reordering buffer in the decoder.
740 * For MPEG-2 it is 1 IPB or 0 low delay IP.
741 * - encoding: Set by libavcodec.
742 * - decoding: Set by libavcodec.
743 */
744 int has_b_frames;
745
746 /**
747 * qscale factor between P- and I-frames
748 * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
749 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
750 * - encoding: Set by user.
751 * - decoding: unused
752 */
753 float i_quant_factor;
754
755 /**
756 * qscale offset between P and I-frames
757 * - encoding: Set by user.
758 * - decoding: unused
759 */
760 float i_quant_offset;
761
762 /**
763 * luminance masking (0-> disabled)
764 * - encoding: Set by user.
765 * - decoding: unused
766 */
767 float lumi_masking;
768
769 /**
770 * temporary complexity masking (0-> disabled)
771 * - encoding: Set by user.
772 * - decoding: unused
773 */
774 float temporal_cplx_masking;
775
776 /**
777 * spatial complexity masking (0-> disabled)
778 * - encoding: Set by user.
779 * - decoding: unused
780 */
781 float spatial_cplx_masking;
782
783 /**
784 * p block masking (0-> disabled)
785 * - encoding: Set by user.
786 * - decoding: unused
787 */
788 float p_masking;
789
790 /**
791 * darkness masking (0-> disabled)
792 * - encoding: Set by user.
793 * - decoding: unused
794 */
795 float dark_masking;
796
797#if FF_API_SLICE_OFFSET
798 /**
799 * slice count
800 * - encoding: Set by libavcodec.
801 * - decoding: Set by user (or 0).
802 */
803 attribute_deprecated
804 int slice_count;
805
806 /**
807 * slice offsets in the frame in bytes
808 * - encoding: Set/allocated by libavcodec.
809 * - decoding: Set/allocated by user (or NULL).
810 */
811 attribute_deprecated
812 int *slice_offset;
813#endif
814
815 /**
816 * sample aspect ratio (0 if unknown)
817 * That is the width of a pixel divided by the height of the pixel.
818 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
819 * - encoding: Set by user.
820 * - decoding: Set by libavcodec.
821 */
822 AVRational sample_aspect_ratio;
823
824 /**
825 * motion estimation comparison function
826 * - encoding: Set by user.
827 * - decoding: unused
828 */
829 int me_cmp;
830 /**
831 * subpixel motion estimation comparison function
832 * - encoding: Set by user.
833 * - decoding: unused
834 */
835 int me_sub_cmp;
836 /**
837 * macroblock comparison function (not supported yet)
838 * - encoding: Set by user.
839 * - decoding: unused
840 */
841 int mb_cmp;
842 /**
843 * interlaced DCT comparison function
844 * - encoding: Set by user.
845 * - decoding: unused
846 */
847 int ildct_cmp;
848#define FF_CMP_SAD 0
849#define FF_CMP_SSE 1
850#define FF_CMP_SATD 2
851#define FF_CMP_DCT 3
852#define FF_CMP_PSNR 4
853#define FF_CMP_BIT 5
854#define FF_CMP_RD 6
855#define FF_CMP_ZERO 7
856#define FF_CMP_VSAD 8
857#define FF_CMP_VSSE 9
858#define FF_CMP_NSSE 10
859#define FF_CMP_W53 11
860#define FF_CMP_W97 12
861#define FF_CMP_DCTMAX 13
862#define FF_CMP_DCT264 14
863#define FF_CMP_MEDIAN_SAD 15
864#define FF_CMP_CHROMA 256
865
866 /**
867 * ME diamond size & shape
868 * - encoding: Set by user.
869 * - decoding: unused
870 */
871 int dia_size;
872
873 /**
874 * amount of previous MV predictors (2a+1 x 2a+1 square)
875 * - encoding: Set by user.
876 * - decoding: unused
877 */
878 int last_predictor_count;
879
880 /**
881 * motion estimation prepass comparison function
882 * - encoding: Set by user.
883 * - decoding: unused
884 */
885 int me_pre_cmp;
886
887 /**
888 * ME prepass diamond size & shape
889 * - encoding: Set by user.
890 * - decoding: unused
891 */
892 int pre_dia_size;
893
894 /**
895 * subpel ME quality
896 * - encoding: Set by user.
897 * - decoding: unused
898 */
899 int me_subpel_quality;
900
901 /**
902 * maximum motion estimation search range in subpel units
903 * If 0 then no limit.
904 *
905 * - encoding: Set by user.
906 * - decoding: unused
907 */
908 int me_range;
909
910 /**
911 * slice flags
912 * - encoding: unused
913 * - decoding: Set by user.
914 */
915 int slice_flags;
916#define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
917#define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
918#define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
919
920 /**
921 * macroblock decision mode
922 * - encoding: Set by user.
923 * - decoding: unused
924 */
925 int mb_decision;
926#define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
927#define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
928#define FF_MB_DECISION_RD 2 ///< rate distortion
929
930 /**
931 * custom intra quantization matrix
932 * Must be allocated with the av_malloc() family of functions, and will be freed in
933 * avcodec_free_context().
934 * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
935 * - decoding: Set/allocated/freed by libavcodec.
936 */
937 uint16_t *intra_matrix;
938
939 /**
940 * custom inter quantization matrix
941 * Must be allocated with the av_malloc() family of functions, and will be freed in
942 * avcodec_free_context().
943 * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
944 * - decoding: Set/allocated/freed by libavcodec.
945 */
946 uint16_t *inter_matrix;
947
948 /**
949 * precision of the intra DC coefficient - 8
950 * - encoding: Set by user.
951 * - decoding: Set by libavcodec
952 */
953 int intra_dc_precision;
954
955 /**
956 * Number of macroblock rows at the top which are skipped.
957 * - encoding: unused
958 * - decoding: Set by user.
959 */
960 int skip_top;
961
962 /**
963 * Number of macroblock rows at the bottom which are skipped.
964 * - encoding: unused
965 * - decoding: Set by user.
966 */
967 int skip_bottom;
968
969 /**
970 * minimum MB Lagrange multiplier
971 * - encoding: Set by user.
972 * - decoding: unused
973 */
974 int mb_lmin;
975
976 /**
977 * maximum MB Lagrange multiplier
978 * - encoding: Set by user.
979 * - decoding: unused
980 */
981 int mb_lmax;
982
983 /**
984 * - encoding: Set by user.
985 * - decoding: unused
986 */
987 int bidir_refine;
988
989 /**
990 * minimum GOP size
991 * - encoding: Set by user.
992 * - decoding: unused
993 */
994 int keyint_min;
995
996 /**
997 * number of reference frames
998 * - encoding: Set by user.
999 * - decoding: Set by lavc.
1000 */
1001 int refs;
1002
1003 /**
1004 * Note: Value depends upon the compare function used for fullpel ME.
1005 * - encoding: Set by user.
1006 * - decoding: unused
1007 */
1008 int mv0_threshold;
1009
1010 /**
1011 * Chromaticity coordinates of the source primaries.
1012 * - encoding: Set by user
1013 * - decoding: Set by libavcodec
1014 */
1015 enum AVColorPrimaries color_primaries;
1016
1017 /**
1018 * Color Transfer Characteristic.
1019 * - encoding: Set by user
1020 * - decoding: Set by libavcodec
1021 */
1022 enum AVColorTransferCharacteristic color_trc;
1023
1024 /**
1025 * YUV colorspace type.
1026 * - encoding: Set by user
1027 * - decoding: Set by libavcodec
1028 */
1029 enum AVColorSpace colorspace;
1030
1031 /**
1032 * MPEG vs JPEG YUV range.
1033 * - encoding: Set by user to override the default output color range value,
1034 * If not specified, libavcodec sets the color range depending on the
1035 * output format.
1036 * - decoding: Set by libavcodec, can be set by the user to propagate the
1037 * color range to components reading from the decoder context.
1038 */
1039 enum AVColorRange color_range;
1040
1041 /**
1042 * This defines the location of chroma samples.
1043 * - encoding: Set by user
1044 * - decoding: Set by libavcodec
1045 */
1046 enum AVChromaLocation chroma_sample_location;
1047
1048 /**
1049 * Number of slices.
1050 * Indicates number of picture subdivisions. Used for parallelized
1051 * decoding.
1052 * - encoding: Set by user
1053 * - decoding: unused
1054 */
1055 int slices;
1056
1057 /** Field order
1058 * - encoding: set by libavcodec
1059 * - decoding: Set by user.
1060 */
1061 enum AVFieldOrder field_order;
1062
1063 /* audio only */
1064 int sample_rate; ///< samples per second
1065
1066#if FF_API_OLD_CHANNEL_LAYOUT
1067 /**
1068 * number of audio channels
1069 * @deprecated use ch_layout.nb_channels
1070 */
1071 attribute_deprecated
1072 int channels;
1073#endif
1074
1075 /**
1076 * audio sample format
1077 * - encoding: Set by user.
1078 * - decoding: Set by libavcodec.
1079 */
1080 enum AVSampleFormat sample_fmt; ///< sample format
1081
1082 /* The following data should not be initialized. */
1083 /**
1084 * Number of samples per channel in an audio frame.
1085 *
1086 * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1087 * except the last must contain exactly frame_size samples per channel.
1088 * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1089 * frame size is not restricted.
1090 * - decoding: may be set by some decoders to indicate constant frame size
1091 */
1092 int frame_size;
1093
1094#if FF_API_AVCTX_FRAME_NUMBER
1095 /**
1096 * Frame counter, set by libavcodec.
1097 *
1098 * - decoding: total number of frames returned from the decoder so far.
1099 * - encoding: total number of frames passed to the encoder so far.
1100 *
1101 * @note the counter is not incremented if encoding/decoding resulted in
1102 * an error.
1103 * @deprecated use frame_num instead
1104 */
1105 attribute_deprecated
1106 int frame_number;
1107#endif
1108
1109 /**
1110 * number of bytes per packet if constant and known or 0
1111 * Used by some WAV based audio codecs.
1112 */
1113 int block_align;
1114
1115 /**
1116 * Audio cutoff bandwidth (0 means "automatic")
1117 * - encoding: Set by user.
1118 * - decoding: unused
1119 */
1120 int cutoff;
1121
1122#if FF_API_OLD_CHANNEL_LAYOUT
1123 /**
1124 * Audio channel layout.
1125 * - encoding: set by user.
1126 * - decoding: set by user, may be overwritten by libavcodec.
1127 * @deprecated use ch_layout
1128 */
1129 attribute_deprecated
1130 uint64_t channel_layout;
1131
1132 /**
1133 * Request decoder to use this channel layout if it can (0 for default)
1134 * - encoding: unused
1135 * - decoding: Set by user.
1136 * @deprecated use "downmix" codec private option
1137 */
1138 attribute_deprecated
1139 uint64_t request_channel_layout;
1140#endif
1141
1142 /**
1143 * Type of service that the audio stream conveys.
1144 * - encoding: Set by user.
1145 * - decoding: Set by libavcodec.
1146 */
1147 enum AVAudioServiceType audio_service_type;
1148
1149 /**
1150 * desired sample format
1151 * - encoding: Not used.
1152 * - decoding: Set by user.
1153 * Decoder will decode to this format if it can.
1154 */
1155 enum AVSampleFormat request_sample_fmt;
1156
1157 /**
1158 * This callback is called at the beginning of each frame to get data
1159 * buffer(s) for it. There may be one contiguous buffer for all the data or
1160 * there may be a buffer per each data plane or anything in between. What
1161 * this means is, you may set however many entries in buf[] you feel necessary.
1162 * Each buffer must be reference-counted using the AVBuffer API (see description
1163 * of buf[] below).
1164 *
1165 * The following fields will be set in the frame before this callback is
1166 * called:
1167 * - format
1168 * - width, height (video only)
1169 * - sample_rate, channel_layout, nb_samples (audio only)
1170 * Their values may differ from the corresponding values in
1171 * AVCodecContext. This callback must use the frame values, not the codec
1172 * context values, to calculate the required buffer size.
1173 *
1174 * This callback must fill the following fields in the frame:
1175 * - data[]
1176 * - linesize[]
1177 * - extended_data:
1178 * * if the data is planar audio with more than 8 channels, then this
1179 * callback must allocate and fill extended_data to contain all pointers
1180 * to all data planes. data[] must hold as many pointers as it can.
1181 * extended_data must be allocated with av_malloc() and will be freed in
1182 * av_frame_unref().
1183 * * otherwise extended_data must point to data
1184 * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1185 * the frame's data and extended_data pointers must be contained in these. That
1186 * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1187 * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1188 * and av_buffer_ref().
1189 * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1190 * this callback and filled with the extra buffers if there are more
1191 * buffers than buf[] can hold. extended_buf will be freed in
1192 * av_frame_unref().
1193 *
1194 * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1195 * avcodec_default_get_buffer2() instead of providing buffers allocated by
1196 * some other means.
1197 *
1198 * Each data plane must be aligned to the maximum required by the target
1199 * CPU.
1200 *
1201 * @see avcodec_default_get_buffer2()
1202 *
1203 * Video:
1204 *
1205 * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1206 * (read and/or written to if it is writable) later by libavcodec.
1207 *
1208 * avcodec_align_dimensions2() should be used to find the required width and
1209 * height, as they normally need to be rounded up to the next multiple of 16.
1210 *
1211 * Some decoders do not support linesizes changing between frames.
1212 *
1213 * If frame multithreading is used, this callback may be called from a
1214 * different thread, but not from more than one at once. Does not need to be
1215 * reentrant.
1216 *
1217 * @see avcodec_align_dimensions2()
1218 *
1219 * Audio:
1220 *
1221 * Decoders request a buffer of a particular size by setting
1222 * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1223 * however, utilize only part of the buffer by setting AVFrame.nb_samples
1224 * to a smaller value in the output frame.
1225 *
1226 * As a convenience, av_samples_get_buffer_size() and
1227 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1228 * functions to find the required data size and to fill data pointers and
1229 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1230 * since all planes must be the same size.
1231 *
1232 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1233 *
1234 * - encoding: unused
1235 * - decoding: Set by libavcodec, user can override.
1236 */
1237 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
1238
1239 /* - encoding parameters */
1240 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1241 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1242
1243 /**
1244 * minimum quantizer
1245 * - encoding: Set by user.
1246 * - decoding: unused
1247 */
1248 int qmin;
1249
1250 /**
1251 * maximum quantizer
1252 * - encoding: Set by user.
1253 * - decoding: unused
1254 */
1255 int qmax;
1256
1257 /**
1258 * maximum quantizer difference between frames
1259 * - encoding: Set by user.
1260 * - decoding: unused
1261 */
1262 int max_qdiff;
1263
1264 /**
1265 * decoder bitstream buffer size
1266 * - encoding: Set by user.
1267 * - decoding: May be set by libavcodec.
1268 */
1269 int rc_buffer_size;
1270
1271 /**
1272 * ratecontrol override, see RcOverride
1273 * - encoding: Allocated/set/freed by user.
1274 * - decoding: unused
1275 */
1276 int rc_override_count;
1277 RcOverride *rc_override;
1278
1279 /**
1280 * maximum bitrate
1281 * - encoding: Set by user.
1282 * - decoding: Set by user, may be overwritten by libavcodec.
1283 */
1284 int64_t rc_max_rate;
1285
1286 /**
1287 * minimum bitrate
1288 * - encoding: Set by user.
1289 * - decoding: unused
1290 */
1291 int64_t rc_min_rate;
1292
1293 /**
1294 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1295 * - encoding: Set by user.
1296 * - decoding: unused.
1297 */
1298 float rc_max_available_vbv_use;
1299
1300 /**
1301 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1302 * - encoding: Set by user.
1303 * - decoding: unused.
1304 */
1305 float rc_min_vbv_overflow_use;
1306
1307 /**
1308 * Number of bits which should be loaded into the rc buffer before decoding starts.
1309 * - encoding: Set by user.
1310 * - decoding: unused
1311 */
1312 int rc_initial_buffer_occupancy;
1313
1314 /**
1315 * trellis RD quantization
1316 * - encoding: Set by user.
1317 * - decoding: unused
1318 */
1319 int trellis;
1320
1321 /**
1322 * pass1 encoding statistics output buffer
1323 * - encoding: Set by libavcodec.
1324 * - decoding: unused
1325 */
1326 char *stats_out;
1327
1328 /**
1329 * pass2 encoding statistics input buffer
1330 * Concatenated stuff from stats_out of pass1 should be placed here.
1331 * - encoding: Allocated/set/freed by user.
1332 * - decoding: unused
1333 */
1334 char *stats_in;
1335
1336 /**
1337 * Work around bugs in encoders which sometimes cannot be detected automatically.
1338 * - encoding: Set by user
1339 * - decoding: Set by user
1340 */
1341 int workaround_bugs;
1342#define FF_BUG_AUTODETECT 1 ///< autodetection
1343#define FF_BUG_XVID_ILACE 4
1344#define FF_BUG_UMP4 8
1345#define FF_BUG_NO_PADDING 16
1346#define FF_BUG_AMV 32
1347#define FF_BUG_QPEL_CHROMA 64
1348#define FF_BUG_STD_QPEL 128
1349#define FF_BUG_QPEL_CHROMA2 256
1350#define FF_BUG_DIRECT_BLOCKSIZE 512
1351#define FF_BUG_EDGE 1024
1352#define FF_BUG_HPEL_CHROMA 2048
1353#define FF_BUG_DC_CLIP 4096
1354#define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1355#define FF_BUG_TRUNCATED 16384
1356#define FF_BUG_IEDGE 32768
1357
1358 /**
1359 * strictly follow the standard (MPEG-4, ...).
1360 * - encoding: Set by user.
1361 * - decoding: Set by user.
1362 * Setting this to STRICT or higher means the encoder and decoder will
1363 * generally do stupid things, whereas setting it to unofficial or lower
1364 * will mean the encoder might produce output that is not supported by all
1365 * spec-compliant decoders. Decoders don't differentiate between normal,
1366 * unofficial and experimental (that is, they always try to decode things
1367 * when they can) unless they are explicitly asked to behave stupidly
1368 * (=strictly conform to the specs)
1369 * This may only be set to one of the FF_COMPLIANCE_* values in defs.h.
1370 */
1371 int strict_std_compliance;
1372
1373 /**
1374 * error concealment flags
1375 * - encoding: unused
1376 * - decoding: Set by user.
1377 */
1378 int error_concealment;
1379#define FF_EC_GUESS_MVS 1
1380#define FF_EC_DEBLOCK 2
1381#define FF_EC_FAVOR_INTER 256
1382
1383 /**
1384 * debug
1385 * - encoding: Set by user.
1386 * - decoding: Set by user.
1387 */
1388 int debug;
1389#define FF_DEBUG_PICT_INFO 1
1390#define FF_DEBUG_RC 2
1391#define FF_DEBUG_BITSTREAM 4
1392#define FF_DEBUG_MB_TYPE 8
1393#define FF_DEBUG_QP 16
1394#define FF_DEBUG_DCT_COEFF 0x00000040
1395#define FF_DEBUG_SKIP 0x00000080
1396#define FF_DEBUG_STARTCODE 0x00000100
1397#define FF_DEBUG_ER 0x00000400
1398#define FF_DEBUG_MMCO 0x00000800
1399#define FF_DEBUG_BUGS 0x00001000
1400#define FF_DEBUG_BUFFERS 0x00008000
1401#define FF_DEBUG_THREADS 0x00010000
1402#define FF_DEBUG_GREEN_MD 0x00800000
1403#define FF_DEBUG_NOMC 0x01000000
1404
1405 /**
1406 * Error recognition; may misdetect some more or less valid parts as errors.
1407 * This is a bitfield of the AV_EF_* values defined in defs.h.
1408 *
1409 * - encoding: Set by user.
1410 * - decoding: Set by user.
1411 */
1412 int err_recognition;
1413
1414#if FF_API_REORDERED_OPAQUE
1415 /**
1416 * opaque 64-bit number (generally a PTS) that will be reordered and
1417 * output in AVFrame.reordered_opaque
1418 * - encoding: Set by libavcodec to the reordered_opaque of the input
1419 * frame corresponding to the last returned packet. Only
1420 * supported by encoders with the
1421 * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1422 * - decoding: Set by user.
1423 *
1424 * @deprecated Use AV_CODEC_FLAG_COPY_OPAQUE instead
1425 */
1426 attribute_deprecated
1427 int64_t reordered_opaque;
1428#endif
1429
1430 /**
1431 * Hardware accelerator in use
1432 * - encoding: unused.
1433 * - decoding: Set by libavcodec
1434 */
1435 const struct AVHWAccel *hwaccel;
1436
1437 /**
1438 * Legacy hardware accelerator context.
1439 *
1440 * For some hardware acceleration methods, the caller may use this field to
1441 * signal hwaccel-specific data to the codec. The struct pointed to by this
1442 * pointer is hwaccel-dependent and defined in the respective header. Please
1443 * refer to the FFmpeg HW accelerator documentation to know how to fill
1444 * this.
1445 *
1446 * In most cases this field is optional - the necessary information may also
1447 * be provided to libavcodec through @ref hw_frames_ctx or @ref
1448 * hw_device_ctx (see avcodec_get_hw_config()). However, in some cases it
1449 * may be the only method of signalling some (optional) information.
1450 *
1451 * The struct and its contents are owned by the caller.
1452 *
1453 * - encoding: May be set by the caller before avcodec_open2(). Must remain
1454 * valid until avcodec_free_context().
1455 * - decoding: May be set by the caller in the get_format() callback.
1456 * Must remain valid until the next get_format() call,
1457 * or avcodec_free_context() (whichever comes first).
1458 */
1459 void *hwaccel_context;
1460
1461 /**
1462 * error
1463 * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1464 * - decoding: unused
1465 */
1466 uint64_t error[AV_NUM_DATA_POINTERS];
1467
1468 /**
1469 * DCT algorithm, see FF_DCT_* below
1470 * - encoding: Set by user.
1471 * - decoding: unused
1472 */
1473 int dct_algo;
1474#define FF_DCT_AUTO 0
1475#define FF_DCT_FASTINT 1
1476#define FF_DCT_INT 2
1477#define FF_DCT_MMX 3
1478#define FF_DCT_ALTIVEC 5
1479#define FF_DCT_FAAN 6
1480
1481 /**
1482 * IDCT algorithm, see FF_IDCT_* below.
1483 * - encoding: Set by user.
1484 * - decoding: Set by user.
1485 */
1486 int idct_algo;
1487#define FF_IDCT_AUTO 0
1488#define FF_IDCT_INT 1
1489#define FF_IDCT_SIMPLE 2
1490#define FF_IDCT_SIMPLEMMX 3
1491#define FF_IDCT_ARM 7
1492#define FF_IDCT_ALTIVEC 8
1493#define FF_IDCT_SIMPLEARM 10
1494#define FF_IDCT_XVID 14
1495#define FF_IDCT_SIMPLEARMV5TE 16
1496#define FF_IDCT_SIMPLEARMV6 17
1497#define FF_IDCT_FAAN 20
1498#define FF_IDCT_SIMPLENEON 22
1499#if FF_API_IDCT_NONE
1500// formerly used by xvmc
1501#define FF_IDCT_NONE 24
1502#endif
1503#define FF_IDCT_SIMPLEAUTO 128
1504
1505 /**
1506 * bits per sample/pixel from the demuxer (needed for huffyuv).
1507 * - encoding: Set by libavcodec.
1508 * - decoding: Set by user.
1509 */
1510 int bits_per_coded_sample;
1511
1512 /**
1513 * Bits per sample/pixel of internal libavcodec pixel/sample format.
1514 * - encoding: set by user.
1515 * - decoding: set by libavcodec.
1516 */
1517 int bits_per_raw_sample;
1518
1519 /**
1520 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1521 * - encoding: unused
1522 * - decoding: Set by user.
1523 */
1524 int lowres;
1525
1526 /**
1527 * thread count
1528 * is used to decide how many independent tasks should be passed to execute()
1529 * - encoding: Set by user.
1530 * - decoding: Set by user.
1531 */
1532 int thread_count;
1533
1534 /**
1535 * Which multithreading methods to use.
1536 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1537 * so clients which cannot provide future frames should not use it.
1538 *
1539 * - encoding: Set by user, otherwise the default is used.
1540 * - decoding: Set by user, otherwise the default is used.
1541 */
1542 int thread_type;
1543#define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1544#define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1545
1546 /**
1547 * Which multithreading methods are in use by the codec.
1548 * - encoding: Set by libavcodec.
1549 * - decoding: Set by libavcodec.
1550 */
1551 int active_thread_type;
1552
1553 /**
1554 * The codec may call this to execute several independent things.
1555 * It will return only after finishing all tasks.
1556 * The user may replace this with some multithreaded implementation,
1557 * the default implementation will execute the parts serially.
1558 * @param count the number of things to execute
1559 * - encoding: Set by libavcodec, user can override.
1560 * - decoding: Set by libavcodec, user can override.
1561 */
1562 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1563
1564 /**
1565 * The codec may call this to execute several independent things.
1566 * It will return only after finishing all tasks.
1567 * The user may replace this with some multithreaded implementation,
1568 * the default implementation will execute the parts serially.
1569 * @param c context passed also to func
1570 * @param count the number of things to execute
1571 * @param arg2 argument passed unchanged to func
1572 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1573 * @param func function that will be called count times, with jobnr from 0 to count-1.
1574 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1575 * two instances of func executing at the same time will have the same threadnr.
1576 * @return always 0 currently, but code should handle a future improvement where when any call to func
1577 * returns < 0 no further calls to func may be done and < 0 is returned.
1578 * - encoding: Set by libavcodec, user can override.
1579 * - decoding: Set by libavcodec, user can override.
1580 */
1581 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1582
1583 /**
1584 * noise vs. sse weight for the nsse comparison function
1585 * - encoding: Set by user.
1586 * - decoding: unused
1587 */
1588 int nsse_weight;
1589
1590 /**
1591 * profile
1592 * - encoding: Set by user.
1593 * - decoding: Set by libavcodec.
1594 * See the AV_PROFILE_* defines in defs.h.
1595 */
1596 int profile;
1597#if FF_API_FF_PROFILE_LEVEL
1598 /** @deprecated The following defines are deprecated; use AV_PROFILE_*
1599 * in defs.h instead. */
1600#define FF_PROFILE_UNKNOWN -99
1601#define FF_PROFILE_RESERVED -100
1602
1603#define FF_PROFILE_AAC_MAIN 0
1604#define FF_PROFILE_AAC_LOW 1
1605#define FF_PROFILE_AAC_SSR 2
1606#define FF_PROFILE_AAC_LTP 3
1607#define FF_PROFILE_AAC_HE 4
1608#define FF_PROFILE_AAC_HE_V2 28
1609#define FF_PROFILE_AAC_LD 22
1610#define FF_PROFILE_AAC_ELD 38
1611#define FF_PROFILE_MPEG2_AAC_LOW 128
1612#define FF_PROFILE_MPEG2_AAC_HE 131
1613
1614#define FF_PROFILE_DNXHD 0
1615#define FF_PROFILE_DNXHR_LB 1
1616#define FF_PROFILE_DNXHR_SQ 2
1617#define FF_PROFILE_DNXHR_HQ 3
1618#define FF_PROFILE_DNXHR_HQX 4
1619#define FF_PROFILE_DNXHR_444 5
1620
1621#define FF_PROFILE_DTS 20
1622#define FF_PROFILE_DTS_ES 30
1623#define FF_PROFILE_DTS_96_24 40
1624#define FF_PROFILE_DTS_HD_HRA 50
1625#define FF_PROFILE_DTS_HD_MA 60
1626#define FF_PROFILE_DTS_EXPRESS 70
1627#define FF_PROFILE_DTS_HD_MA_X 61
1628#define FF_PROFILE_DTS_HD_MA_X_IMAX 62
1629
1630
1631#define FF_PROFILE_EAC3_DDP_ATMOS 30
1632
1633#define FF_PROFILE_TRUEHD_ATMOS 30
1634
1635#define FF_PROFILE_MPEG2_422 0
1636#define FF_PROFILE_MPEG2_HIGH 1
1637#define FF_PROFILE_MPEG2_SS 2
1638#define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1639#define FF_PROFILE_MPEG2_MAIN 4
1640#define FF_PROFILE_MPEG2_SIMPLE 5
1641
1642#define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1643#define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1644
1645#define FF_PROFILE_H264_BASELINE 66
1646#define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1647#define FF_PROFILE_H264_MAIN 77
1648#define FF_PROFILE_H264_EXTENDED 88
1649#define FF_PROFILE_H264_HIGH 100
1650#define FF_PROFILE_H264_HIGH_10 110
1651#define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1652#define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1653#define FF_PROFILE_H264_HIGH_422 122
1654#define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1655#define FF_PROFILE_H264_STEREO_HIGH 128
1656#define FF_PROFILE_H264_HIGH_444 144
1657#define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1658#define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1659#define FF_PROFILE_H264_CAVLC_444 44
1660
1661#define FF_PROFILE_VC1_SIMPLE 0
1662#define FF_PROFILE_VC1_MAIN 1
1663#define FF_PROFILE_VC1_COMPLEX 2
1664#define FF_PROFILE_VC1_ADVANCED 3
1665
1666#define FF_PROFILE_MPEG4_SIMPLE 0
1667#define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1668#define FF_PROFILE_MPEG4_CORE 2
1669#define FF_PROFILE_MPEG4_MAIN 3
1670#define FF_PROFILE_MPEG4_N_BIT 4
1671#define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1672#define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1673#define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1674#define FF_PROFILE_MPEG4_HYBRID 8
1675#define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1676#define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1677#define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1678#define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1679#define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1680#define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1681#define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1682
1683#define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1684#define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1685#define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1686#define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1687#define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1688
1689#define FF_PROFILE_VP9_0 0
1690#define FF_PROFILE_VP9_1 1
1691#define FF_PROFILE_VP9_2 2
1692#define FF_PROFILE_VP9_3 3
1693
1694#define FF_PROFILE_HEVC_MAIN 1
1695#define FF_PROFILE_HEVC_MAIN_10 2
1696#define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1697#define FF_PROFILE_HEVC_REXT 4
1698#define FF_PROFILE_HEVC_SCC 9
1699
1700#define FF_PROFILE_VVC_MAIN_10 1
1701#define FF_PROFILE_VVC_MAIN_10_444 33
1702
1703#define FF_PROFILE_AV1_MAIN 0
1704#define FF_PROFILE_AV1_HIGH 1
1705#define FF_PROFILE_AV1_PROFESSIONAL 2
1706
1707#define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1708#define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1709#define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1710#define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1711#define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1712
1713#define FF_PROFILE_SBC_MSBC 1
1714
1715#define FF_PROFILE_PRORES_PROXY 0
1716#define FF_PROFILE_PRORES_LT 1
1717#define FF_PROFILE_PRORES_STANDARD 2
1718#define FF_PROFILE_PRORES_HQ 3
1719#define FF_PROFILE_PRORES_4444 4
1720#define FF_PROFILE_PRORES_XQ 5
1721
1722#define FF_PROFILE_ARIB_PROFILE_A 0
1723#define FF_PROFILE_ARIB_PROFILE_C 1
1724
1725#define FF_PROFILE_KLVA_SYNC 0
1726#define FF_PROFILE_KLVA_ASYNC 1
1727
1728#define FF_PROFILE_EVC_BASELINE 0
1729#define FF_PROFILE_EVC_MAIN 1
1730#endif
1731
1732 /**
1733 * Encoding level descriptor.
1734 * - encoding: Set by user, corresponds to a specific level defined by the
1735 * codec, usually corresponding to the profile level, if not specified it
1736 * is set to FF_LEVEL_UNKNOWN.
1737 * - decoding: Set by libavcodec.
1738 * See AV_LEVEL_* in defs.h.
1739 */
1740 int level;
1741#if FF_API_FF_PROFILE_LEVEL
1742 /** @deprecated The following define is deprecated; use AV_LEVEL_UNKOWN
1743 * in defs.h instead. */
1744#define FF_LEVEL_UNKNOWN -99
1745#endif
1746
1747 /**
1748 * Skip loop filtering for selected frames.
1749 * - encoding: unused
1750 * - decoding: Set by user.
1751 */
1752 enum AVDiscard skip_loop_filter;
1753
1754 /**
1755 * Skip IDCT/dequantization for selected frames.
1756 * - encoding: unused
1757 * - decoding: Set by user.
1758 */
1759 enum AVDiscard skip_idct;
1760
1761 /**
1762 * Skip decoding for selected frames.
1763 * - encoding: unused
1764 * - decoding: Set by user.
1765 */
1766 enum AVDiscard skip_frame;
1767
1768 /**
1769 * Header containing style information for text subtitles.
1770 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
1771 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
1772 * the Format line following. It shouldn't include any Dialogue line.
1773 * - encoding: Set/allocated/freed by user (before avcodec_open2())
1774 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
1775 */
1776 uint8_t *subtitle_header;
1777 int subtitle_header_size;
1778
1779 /**
1780 * Audio only. The number of "priming" samples (padding) inserted by the
1781 * encoder at the beginning of the audio. I.e. this number of leading
1782 * decoded samples must be discarded by the caller to get the original audio
1783 * without leading padding.
1784 *
1785 * - decoding: unused
1786 * - encoding: Set by libavcodec. The timestamps on the output packets are
1787 * adjusted by the encoder so that they always refer to the
1788 * first sample of the data actually contained in the packet,
1789 * including any added padding. E.g. if the timebase is
1790 * 1/samplerate and the timestamp of the first input sample is
1791 * 0, the timestamp of the first output packet will be
1792 * -initial_padding.
1793 */
1794 int initial_padding;
1795
1796 /**
1797 * - decoding: For codecs that store a framerate value in the compressed
1798 * bitstream, the decoder may export it here. { 0, 1} when
1799 * unknown.
1800 * - encoding: May be used to signal the framerate of CFR content to an
1801 * encoder.
1802 */
1803 AVRational framerate;
1804
1805 /**
1806 * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
1807 * - encoding: unused.
1808 * - decoding: Set by libavcodec before calling get_format()
1809 */
1810 enum AVPixelFormat sw_pix_fmt;
1811
1812 /**
1813 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are expressed.
1814 * - encoding: unused.
1815 * - decoding: set by user.
1816 */
1817 AVRational pkt_timebase;
1818
1819 /**
1820 * AVCodecDescriptor
1821 * - encoding: unused.
1822 * - decoding: set by libavcodec.
1823 */
1824 const struct AVCodecDescriptor *codec_descriptor;
1825
1826 /**
1827 * Current statistics for PTS correction.
1828 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
1829 * - encoding: unused
1830 */
1831 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
1832 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
1833 int64_t pts_correction_last_pts; /// PTS of the last frame
1834 int64_t pts_correction_last_dts; /// DTS of the last frame
1835
1836 /**
1837 * Character encoding of the input subtitles file.
1838 * - decoding: set by user
1839 * - encoding: unused
1840 */
1841 char *sub_charenc;
1842
1843 /**
1844 * Subtitles character encoding mode. Formats or codecs might be adjusting
1845 * this setting (if they are doing the conversion themselves for instance).
1846 * - decoding: set by libavcodec
1847 * - encoding: unused
1848 */
1849 int sub_charenc_mode;
1850#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)
1851#define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
1852#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
1853#define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
1854
1855 /**
1856 * Skip processing alpha if supported by codec.
1857 * Note that if the format uses pre-multiplied alpha (common with VP6,
1858 * and recommended due to better video quality/compression)
1859 * the image will look as if alpha-blended onto a black background.
1860 * However for formats that do not use pre-multiplied alpha
1861 * there might be serious artefacts (though e.g. libswscale currently
1862 * assumes pre-multiplied alpha anyway).
1863 *
1864 * - decoding: set by user
1865 * - encoding: unused
1866 */
1867 int skip_alpha;
1868
1869 /**
1870 * Number of samples to skip after a discontinuity
1871 * - decoding: unused
1872 * - encoding: set by libavcodec
1873 */
1874 int seek_preroll;
1875
1876 /**
1877 * custom intra quantization matrix
1878 * - encoding: Set by user, can be NULL.
1879 * - decoding: unused.
1880 */
1881 uint16_t *chroma_intra_matrix;
1882
1883 /**
1884 * dump format separator.
1885 * can be ", " or "\n " or anything else
1886 * - encoding: Set by user.
1887 * - decoding: Set by user.
1888 */
1889 uint8_t *dump_separator;
1890
1891 /**
1892 * ',' separated list of allowed decoders.
1893 * If NULL then all are allowed
1894 * - encoding: unused
1895 * - decoding: set by user
1896 */
1897 char *codec_whitelist;
1898
1899 /**
1900 * Properties of the stream that gets decoded
1901 * - encoding: unused
1902 * - decoding: set by libavcodec
1903 */
1904 unsigned properties;
1905#define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
1906#define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
1907#define FF_CODEC_PROPERTY_FILM_GRAIN 0x00000004
1908
1909 /**
1910 * Additional data associated with the entire coded stream.
1911 *
1912 * - decoding: may be set by user before calling avcodec_open2().
1913 * - encoding: may be set by libavcodec after avcodec_open2().
1914 */
1915 AVPacketSideData *coded_side_data;
1916 int nb_coded_side_data;
1917
1918 /**
1919 * A reference to the AVHWFramesContext describing the input (for encoding)
1920 * or output (decoding) frames. The reference is set by the caller and
1921 * afterwards owned (and freed) by libavcodec - it should never be read by
1922 * the caller after being set.
1923 *
1924 * - decoding: This field should be set by the caller from the get_format()
1925 * callback. The previous reference (if any) will always be
1926 * unreffed by libavcodec before the get_format() call.
1927 *
1928 * If the default get_buffer2() is used with a hwaccel pixel
1929 * format, then this AVHWFramesContext will be used for
1930 * allocating the frame buffers.
1931 *
1932 * - encoding: For hardware encoders configured to use a hwaccel pixel
1933 * format, this field should be set by the caller to a reference
1934 * to the AVHWFramesContext describing input frames.
1935 * AVHWFramesContext.format must be equal to
1936 * AVCodecContext.pix_fmt.
1937 *
1938 * This field should be set before avcodec_open2() is called.
1939 */
1940 AVBufferRef *hw_frames_ctx;
1941
1942 /**
1943 * Audio only. The amount of padding (in samples) appended by the encoder to
1944 * the end of the audio. I.e. this number of decoded samples must be
1945 * discarded by the caller from the end of the stream to get the original
1946 * audio without any trailing padding.
1947 *
1948 * - decoding: unused
1949 * - encoding: unused
1950 */
1951 int trailing_padding;
1952
1953 /**
1954 * The number of pixels per image to maximally accept.
1955 *
1956 * - decoding: set by user
1957 * - encoding: set by user
1958 */
1959 int64_t max_pixels;
1960
1961 /**
1962 * A reference to the AVHWDeviceContext describing the device which will
1963 * be used by a hardware encoder/decoder. The reference is set by the
1964 * caller and afterwards owned (and freed) by libavcodec.
1965 *
1966 * This should be used if either the codec device does not require
1967 * hardware frames or any that are used are to be allocated internally by
1968 * libavcodec. If the user wishes to supply any of the frames used as
1969 * encoder input or decoder output then hw_frames_ctx should be used
1970 * instead. When hw_frames_ctx is set in get_format() for a decoder, this
1971 * field will be ignored while decoding the associated stream segment, but
1972 * may again be used on a following one after another get_format() call.
1973 *
1974 * For both encoders and decoders this field should be set before
1975 * avcodec_open2() is called and must not be written to thereafter.
1976 *
1977 * Note that some decoders may require this field to be set initially in
1978 * order to support hw_frames_ctx at all - in that case, all frames
1979 * contexts used must be created on the same device.
1980 */
1981 AVBufferRef *hw_device_ctx;
1982
1983 /**
1984 * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
1985 * decoding (if active).
1986 * - encoding: unused
1987 * - decoding: Set by user (either before avcodec_open2(), or in the
1988 * AVCodecContext.get_format callback)
1989 */
1990 int hwaccel_flags;
1991
1992 /**
1993 * Video decoding only. Certain video codecs support cropping, meaning that
1994 * only a sub-rectangle of the decoded frame is intended for display. This
1995 * option controls how cropping is handled by libavcodec.
1996 *
1997 * When set to 1 (the default), libavcodec will apply cropping internally.
1998 * I.e. it will modify the output frame width/height fields and offset the
1999 * data pointers (only by as much as possible while preserving alignment, or
2000 * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
2001 * the frames output by the decoder refer only to the cropped area. The
2002 * crop_* fields of the output frames will be zero.
2003 *
2004 * When set to 0, the width/height fields of the output frames will be set
2005 * to the coded dimensions and the crop_* fields will describe the cropping
2006 * rectangle. Applying the cropping is left to the caller.
2007 *
2008 * @warning When hardware acceleration with opaque output frames is used,
2009 * libavcodec is unable to apply cropping from the top/left border.
2010 *
2011 * @note when this option is set to zero, the width/height fields of the
2012 * AVCodecContext and output AVFrames have different meanings. The codec
2013 * context fields store display dimensions (with the coded dimensions in
2014 * coded_width/height), while the frame fields store the coded dimensions
2015 * (with the display dimensions being determined by the crop_* fields).
2016 */
2017 int apply_cropping;
2018
2019 /*
2020 * Video decoding only. Sets the number of extra hardware frames which
2021 * the decoder will allocate for use by the caller. This must be set
2022 * before avcodec_open2() is called.
2023 *
2024 * Some hardware decoders require all frames that they will use for
2025 * output to be defined in advance before decoding starts. For such
2026 * decoders, the hardware frame pool must therefore be of a fixed size.
2027 * The extra frames set here are on top of any number that the decoder
2028 * needs internally in order to operate normally (for example, frames
2029 * used as reference pictures).
2030 */
2031 int extra_hw_frames;
2032
2033 /**
2034 * The percentage of damaged samples to discard a frame.
2035 *
2036 * - decoding: set by user
2037 * - encoding: unused
2038 */
2039 int discard_damaged_percentage;
2040
2041 /**
2042 * The number of samples per frame to maximally accept.
2043 *
2044 * - decoding: set by user
2045 * - encoding: set by user
2046 */
2047 int64_t max_samples;
2048
2049 /**
2050 * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
2051 * metadata exported in frame, packet, or coded stream side data by
2052 * decoders and encoders.
2053 *
2054 * - decoding: set by user
2055 * - encoding: set by user
2056 */
2057 int export_side_data;
2058
2059 /**
2060 * This callback is called at the beginning of each packet to get a data
2061 * buffer for it.
2062 *
2063 * The following field will be set in the packet before this callback is
2064 * called:
2065 * - size
2066 * This callback must use the above value to calculate the required buffer size,
2067 * which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
2068 *
2069 * In some specific cases, the encoder may not use the entire buffer allocated by this
2070 * callback. This will be reflected in the size value in the packet once returned by
2071 * avcodec_receive_packet().
2072 *
2073 * This callback must fill the following fields in the packet:
2074 * - data: alignment requirements for AVPacket apply, if any. Some architectures and
2075 * encoders may benefit from having aligned data.
2076 * - buf: must contain a pointer to an AVBufferRef structure. The packet's
2077 * data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
2078 * and av_buffer_ref().
2079 *
2080 * If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2081 * avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2082 * some other means.
2083 *
2084 * The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2085 * They may be used for example to hint what use the buffer may get after being
2086 * created.
2087 * Implementations of this callback may ignore flags they don't understand.
2088 * If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2089 * (read and/or written to if it is writable) later by libavcodec.
2090 *
2091 * This callback must be thread-safe, as when frame threading is used, it may
2092 * be called from multiple threads simultaneously.
2093 *
2094 * @see avcodec_default_get_encode_buffer()
2095 *
2096 * - encoding: Set by libavcodec, user can override.
2097 * - decoding: unused
2098 */
2099 int (*get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags);
2100
2101 /**
2102 * Audio channel layout.
2103 * - encoding: must be set by the caller, to one of AVCodec.ch_layouts.
2104 * - decoding: may be set by the caller if known e.g. from the container.
2105 * The decoder can then override during decoding as needed.
2106 */
2107 AVChannelLayout ch_layout;
2108
2109 /**
2110 * Frame counter, set by libavcodec.
2111 *
2112 * - decoding: total number of frames returned from the decoder so far.
2113 * - encoding: total number of frames passed to the encoder so far.
2114 *
2115 * @note the counter is not incremented if encoding/decoding resulted in
2116 * an error.
2117 */
2118 int64_t frame_num;
2119} AVCodecContext;
2120
2121/**
2122 * @defgroup lavc_hwaccel AVHWAccel
2123 *
2124 * @note Nothing in this structure should be accessed by the user. At some
2125 * point in future it will not be externally visible at all.
2126 *
2127 * @{
2128 */
2129typedef struct AVHWAccel {
2130 /**
2131 * Name of the hardware accelerated codec.
2132 * The name is globally unique among encoders and among decoders (but an
2133 * encoder and a decoder can share the same name).
2134 */
2135 const char *name;
2136
2137 /**
2138 * Type of codec implemented by the hardware accelerator.
2139 *
2140 * See AVMEDIA_TYPE_xxx
2141 */
2142 enum AVMediaType type;
2143
2144 /**
2145 * Codec implemented by the hardware accelerator.
2146 *
2147 * See AV_CODEC_ID_xxx
2148 */
2149 enum AVCodecID id;
2150
2151 /**
2152 * Supported pixel format.
2153 *
2154 * Only hardware accelerated formats are supported here.
2155 */
2156 enum AVPixelFormat pix_fmt;
2157
2158 /**
2159 * Hardware accelerated codec capabilities.
2160 * see AV_HWACCEL_CODEC_CAP_*
2161 */
2162 int capabilities;
2163} AVHWAccel;
2164
2165/**
2166 * HWAccel is experimental and is thus avoided in favor of non experimental
2167 * codecs
2168 */
2169#define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2170
2171/**
2172 * Hardware acceleration should be used for decoding even if the codec level
2173 * used is unknown or higher than the maximum supported level reported by the
2174 * hardware driver.
2175 *
2176 * It's generally a good idea to pass this flag unless you have a specific
2177 * reason not to, as hardware tends to under-report supported levels.
2178 */
2179#define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2180
2181/**
2182 * Hardware acceleration can output YUV pixel formats with a different chroma
2183 * sampling than 4:2:0 and/or other than 8 bits per component.
2184 */
2185#define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2186
2187/**
2188 * Hardware acceleration should still be attempted for decoding when the
2189 * codec profile does not match the reported capabilities of the hardware.
2190 *
2191 * For example, this can be used to try to decode baseline profile H.264
2192 * streams in hardware - it will often succeed, because many streams marked
2193 * as baseline profile actually conform to constrained baseline profile.
2194 *
2195 * @warning If the stream is actually not supported then the behaviour is
2196 * undefined, and may include returning entirely incorrect output
2197 * while indicating success.
2198 */
2199#define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2200
2201/**
2202 * Some hardware decoders (namely nvdec) can either output direct decoder
2203 * surfaces, or make an on-device copy and return said copy.
2204 * There is a hard limit on how many decoder surfaces there can be, and it
2205 * cannot be accurately guessed ahead of time.
2206 * For some processing chains, this can be okay, but others will run into the
2207 * limit and in turn produce very confusing errors that require fine tuning of
2208 * more or less obscure options by the user, or in extreme cases cannot be
2209 * resolved at all without inserting an avfilter that forces a copy.
2210 *
2211 * Thus, the hwaccel will by default make a copy for safety and resilience.
2212 * If a users really wants to minimize the amount of copies, they can set this
2213 * flag and ensure their processing chain does not exhaust the surface pool.
2214 */
2215#define AV_HWACCEL_FLAG_UNSAFE_OUTPUT (1 << 3)
2216
2217/**
2218 * @}
2219 */
2220
2221enum AVSubtitleType {
2222 SUBTITLE_NONE,
2223
2224 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2225
2226 /**
2227 * Plain text, the text field must be set by the decoder and is
2228 * authoritative. ass and pict fields may contain approximations.
2229 */
2230 SUBTITLE_TEXT,
2231
2232 /**
2233 * Formatted text, the ass field must be set by the decoder and is
2234 * authoritative. pict and text fields may contain approximations.
2235 */
2236 SUBTITLE_ASS,
2237};
2238
2239#define AV_SUBTITLE_FLAG_FORCED 0x00000001
2240
2241typedef struct AVSubtitleRect {
2242 int x; ///< top left corner of pict, undefined when pict is not set
2243 int y; ///< top left corner of pict, undefined when pict is not set
2244 int w; ///< width of pict, undefined when pict is not set
2245 int h; ///< height of pict, undefined when pict is not set
2246 int nb_colors; ///< number of colors in pict, undefined when pict is not set
2247
2248 /**
2249 * data+linesize for the bitmap of this subtitle.
2250 * Can be set for text/ass as well once they are rendered.
2251 */
2252 uint8_t *data[4];
2253 int linesize[4];
2254
2255 enum AVSubtitleType type;
2256
2257 char *text; ///< 0 terminated plain UTF-8 text
2258
2259 /**
2260 * 0 terminated ASS/SSA compatible event line.
2261 * The presentation of this is unaffected by the other values in this
2262 * struct.
2263 */
2264 char *ass;
2265
2266 int flags;
2267} AVSubtitleRect;
2268
2269typedef struct AVSubtitle {
2270 uint16_t format; /* 0 = graphics */
2271 uint32_t start_display_time; /* relative to packet pts, in ms */
2272 uint32_t end_display_time; /* relative to packet pts, in ms */
2273 unsigned num_rects;
2274 AVSubtitleRect **rects;
2275 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2276} AVSubtitle;
2277
2278/**
2279 * Return the LIBAVCODEC_VERSION_INT constant.
2280 */
2281unsigned avcodec_version(void);
2282
2283/**
2284 * Return the libavcodec build-time configuration.
2285 */
2286const char *avcodec_configuration(void);
2287
2288/**
2289 * Return the libavcodec license.
2290 */
2291const char *avcodec_license(void);
2292
2293/**
2294 * Allocate an AVCodecContext and set its fields to default values. The
2295 * resulting struct should be freed with avcodec_free_context().
2296 *
2297 * @param codec if non-NULL, allocate private data and initialize defaults
2298 * for the given codec. It is illegal to then call avcodec_open2()
2299 * with a different codec.
2300 * If NULL, then the codec-specific defaults won't be initialized,
2301 * which may result in suboptimal default settings (this is
2302 * important mainly for encoders, e.g. libx264).
2303 *
2304 * @return An AVCodecContext filled with default values or NULL on failure.
2305 */
2306AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
2307
2308/**
2309 * Free the codec context and everything associated with it and write NULL to
2310 * the provided pointer.
2311 */
2312void avcodec_free_context(AVCodecContext **avctx);
2313
2314/**
2315 * Get the AVClass for AVCodecContext. It can be used in combination with
2316 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2317 *
2318 * @see av_opt_find().
2319 */
2320const AVClass *avcodec_get_class(void);
2321
2322/**
2323 * Get the AVClass for AVSubtitleRect. It can be used in combination with
2324 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2325 *
2326 * @see av_opt_find().
2327 */
2328const AVClass *avcodec_get_subtitle_rect_class(void);
2329
2330/**
2331 * Fill the parameters struct based on the values from the supplied codec
2332 * context. Any allocated fields in par are freed and replaced with duplicates
2333 * of the corresponding fields in codec.
2334 *
2335 * @return >= 0 on success, a negative AVERROR code on failure
2336 */
2337int avcodec_parameters_from_context(struct AVCodecParameters *par,
2338 const AVCodecContext *codec);
2339
2340/**
2341 * Fill the codec context based on the values from the supplied codec
2342 * parameters. Any allocated fields in codec that have a corresponding field in
2343 * par are freed and replaced with duplicates of the corresponding field in par.
2344 * Fields in codec that do not have a counterpart in par are not touched.
2345 *
2346 * @return >= 0 on success, a negative AVERROR code on failure.
2347 */
2348int avcodec_parameters_to_context(AVCodecContext *codec,
2349 const struct AVCodecParameters *par);
2350
2351/**
2352 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2353 * function the context has to be allocated with avcodec_alloc_context3().
2354 *
2355 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2356 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2357 * retrieving a codec.
2358 *
2359 * Depending on the codec, you might need to set options in the codec context
2360 * also for decoding (e.g. width, height, or the pixel or audio sample format in
2361 * the case the information is not available in the bitstream, as when decoding
2362 * raw audio or video).
2363 *
2364 * Options in the codec context can be set either by setting them in the options
2365 * AVDictionary, or by setting the values in the context itself, directly or by
2366 * using the av_opt_set() API before calling this function.
2367 *
2368 * Example:
2369 * @code
2370 * av_dict_set(&opts, "b", "2.5M", 0);
2371 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2372 * if (!codec)
2373 * exit(1);
2374 *
2375 * context = avcodec_alloc_context3(codec);
2376 *
2377 * if (avcodec_open2(context, codec, opts) < 0)
2378 * exit(1);
2379 * @endcode
2380 *
2381 * In the case AVCodecParameters are available (e.g. when demuxing a stream
2382 * using libavformat, and accessing the AVStream contained in the demuxer), the
2383 * codec parameters can be copied to the codec context using
2384 * avcodec_parameters_to_context(), as in the following example:
2385 *
2386 * @code
2387 * AVStream *stream = ...;
2388 * context = avcodec_alloc_context3(codec);
2389 * if (avcodec_parameters_to_context(context, stream->codecpar) < 0)
2390 * exit(1);
2391 * if (avcodec_open2(context, codec, NULL) < 0)
2392 * exit(1);
2393 * @endcode
2394 *
2395 * @note Always call this function before using decoding routines (such as
2396 * @ref avcodec_receive_frame()).
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
2404 * options, which are set on top of the options already set in
2405 * avctx, can be NULL. On return this object will be filled with
2406 * options that were not found in the avctx codec context.
2407 *
2408 * @return zero on success, a negative value on error
2409 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2410 * av_dict_set(), av_opt_set(), av_opt_find(), avcodec_parameters_to_context()
2411 */
2412int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2413
2414/**
2415 * Close a given AVCodecContext and free all the data associated with it
2416 * (but not the AVCodecContext itself).
2417 *
2418 * Calling this function on an AVCodecContext that hasn't been opened will free
2419 * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2420 * codec. Subsequent calls will do nothing.
2421 *
2422 * @note Do not use this function. Use avcodec_free_context() to destroy a
2423 * codec context (either open or closed). Opening and closing a codec context
2424 * multiple times is not supported anymore -- use multiple codec contexts
2425 * instead.
2426 */
2427int avcodec_close(AVCodecContext *avctx);
2428
2429/**
2430 * Free all allocated data in the given subtitle struct.
2431 *
2432 * @param sub AVSubtitle to free.
2433 */
2434void avsubtitle_free(AVSubtitle *sub);
2435
2436/**
2437 * @}
2438 */
2439
2440/**
2441 * @addtogroup lavc_decoding
2442 * @{
2443 */
2444
2445/**
2446 * The default callback for AVCodecContext.get_buffer2(). It is made public so
2447 * it can be called by custom get_buffer2() implementations for decoders without
2448 * AV_CODEC_CAP_DR1 set.
2449 */
2450int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
2451
2452/**
2453 * The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2454 * it can be called by custom get_encode_buffer() implementations for encoders without
2455 * AV_CODEC_CAP_DR1 set.
2456 */
2457int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags);
2458
2459/**
2460 * Modify width and height values so that they will result in a memory
2461 * buffer that is acceptable for the codec if you do not use any horizontal
2462 * padding.
2463 *
2464 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2465 */
2466void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
2467
2468/**
2469 * Modify width and height values so that they will result in a memory
2470 * buffer that is acceptable for the codec if you also ensure that all
2471 * line sizes are a multiple of the respective linesize_align[i].
2472 *
2473 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2474 */
2475void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
2476 int linesize_align[AV_NUM_DATA_POINTERS]);
2477
2478#ifdef FF_API_AVCODEC_CHROMA_POS
2479/**
2480 * Converts AVChromaLocation to swscale x/y chroma position.
2481 *
2482 * The positions represent the chroma (0,0) position in a coordinates system
2483 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2484 *
2485 * @param xpos horizontal chroma sample position
2486 * @param ypos vertical chroma sample position
2487 * @deprecated Use av_chroma_location_enum_to_pos() instead.
2488 */
2489 attribute_deprecated
2490int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
2491
2492/**
2493 * Converts swscale x/y chroma position to AVChromaLocation.
2494 *
2495 * The positions represent the chroma (0,0) position in a coordinates system
2496 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2497 *
2498 * @param xpos horizontal chroma sample position
2499 * @param ypos vertical chroma sample position
2500 * @deprecated Use av_chroma_location_pos_to_enum() instead.
2501 */
2502 attribute_deprecated
2503enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
2504#endif
2505
2506/**
2507 * Decode a subtitle message.
2508 * Return a negative value on error, otherwise return the number of bytes used.
2509 * If no subtitle could be decompressed, got_sub_ptr is zero.
2510 * Otherwise, the subtitle is stored in *sub.
2511 * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
2512 * simplicity, because the performance difference is expected to be negligible
2513 * and reusing a get_buffer written for video codecs would probably perform badly
2514 * due to a potentially very different allocation pattern.
2515 *
2516 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2517 * and output. This means that for some packets they will not immediately
2518 * produce decoded output and need to be flushed at the end of decoding to get
2519 * all the decoded data. Flushing is done by calling this function with packets
2520 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2521 * returning subtitles. It is safe to flush even those decoders that are not
2522 * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
2523 *
2524 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2525 * before packets may be fed to the decoder.
2526 *
2527 * @param avctx the codec context
2528 * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
2529 * must be freed with avsubtitle_free if *got_sub_ptr is set.
2530 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
2531 * @param[in] avpkt The input AVPacket containing the input buffer.
2532 */
2533int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
2534 int *got_sub_ptr, const AVPacket *avpkt);
2535
2536/**
2537 * Supply raw packet data as input to a decoder.
2538 *
2539 * Internally, this call will copy relevant AVCodecContext fields, which can
2540 * influence decoding per-packet, and apply them when the packet is actually
2541 * decoded. (For example AVCodecContext.skip_frame, which might direct the
2542 * decoder to drop the frame contained by the packet sent with this function.)
2543 *
2544 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2545 * larger than the actual read bytes because some optimized bitstream
2546 * readers read 32 or 64 bits at once and could read over the end.
2547 *
2548 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2549 * before packets may be fed to the decoder.
2550 *
2551 * @param avctx codec context
2552 * @param[in] avpkt The input AVPacket. Usually, this will be a single video
2553 * frame, or several complete audio frames.
2554 * Ownership of the packet remains with the caller, and the
2555 * decoder will not write to the packet. The decoder may create
2556 * a reference to the packet data (or copy it if the packet is
2557 * not reference-counted).
2558 * Unlike with older APIs, the packet is always fully consumed,
2559 * and if it contains multiple frames (e.g. some audio codecs),
2560 * will require you to call avcodec_receive_frame() multiple
2561 * times afterwards before you can send a new packet.
2562 * It can be NULL (or an AVPacket with data set to NULL and
2563 * size set to 0); in this case, it is considered a flush
2564 * packet, which signals the end of the stream. Sending the
2565 * first flush packet will return success. Subsequent ones are
2566 * unnecessary and will return AVERROR_EOF. If the decoder
2567 * still has frames buffered, it will return them after sending
2568 * a flush packet.
2569 *
2570 * @retval 0 success
2571 * @retval AVERROR(EAGAIN) input is not accepted in the current state - user
2572 * must read output with avcodec_receive_frame() (once
2573 * all output is read, the packet should be resent,
2574 * and the call will not fail with EAGAIN).
2575 * @retval AVERROR_EOF the decoder has been flushed, and no new packets can be
2576 * sent to it (also returned if more than 1 flush
2577 * packet is sent)
2578 * @retval AVERROR(EINVAL) codec not opened, it is an encoder, or requires flush
2579 * @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
2580 * @retval "another negative error code" legitimate decoding errors
2581 */
2582int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
2583
2584/**
2585 * Return decoded output data from a decoder or encoder (when the
2586 * @ref AV_CODEC_FLAG_RECON_FRAME flag is used).
2587 *
2588 * @param avctx codec context
2589 * @param frame This will be set to a reference-counted video or audio
2590 * frame (depending on the decoder type) allocated by the
2591 * codec. Note that the function will always call
2592 * av_frame_unref(frame) before doing anything else.
2593 *
2594 * @retval 0 success, a frame was returned
2595 * @retval AVERROR(EAGAIN) output is not available in this state - user must
2596 * try to send new input
2597 * @retval AVERROR_EOF the codec has been fully flushed, and there will be
2598 * no more output frames
2599 * @retval AVERROR(EINVAL) codec not opened, or it is an encoder without the
2600 * @ref AV_CODEC_FLAG_RECON_FRAME flag enabled
2601 * @retval "other negative error code" legitimate decoding errors
2602 */
2603int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
2604
2605/**
2606 * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
2607 * to retrieve buffered output packets.
2608 *
2609 * @param avctx codec context
2610 * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
2611 * Ownership of the frame remains with the caller, and the
2612 * encoder will not write to the frame. The encoder may create
2613 * a reference to the frame data (or copy it if the frame is
2614 * not reference-counted).
2615 * It can be NULL, in which case it is considered a flush
2616 * packet. This signals the end of the stream. If the encoder
2617 * still has packets buffered, it will return them after this
2618 * call. Once flushing mode has been entered, additional flush
2619 * packets are ignored, and sending frames will return
2620 * AVERROR_EOF.
2621 *
2622 * For audio:
2623 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
2624 * can have any number of samples.
2625 * If it is not set, frame->nb_samples must be equal to
2626 * avctx->frame_size for all frames except the last.
2627 * The final frame may be smaller than avctx->frame_size.
2628 * @retval 0 success
2629 * @retval AVERROR(EAGAIN) input is not accepted in the current state - user must
2630 * read output with avcodec_receive_packet() (once all
2631 * output is read, the packet should be resent, and the
2632 * call will not fail with EAGAIN).
2633 * @retval AVERROR_EOF the encoder has been flushed, and no new frames can
2634 * be sent to it
2635 * @retval AVERROR(EINVAL) codec not opened, it is a decoder, or requires flush
2636 * @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
2637 * @retval "another negative error code" legitimate encoding errors
2638 */
2639int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
2640
2641/**
2642 * Read encoded data from the encoder.
2643 *
2644 * @param avctx codec context
2645 * @param avpkt This will be set to a reference-counted packet allocated by the
2646 * encoder. Note that the function will always call
2647 * av_packet_unref(avpkt) before doing anything else.
2648 * @retval 0 success
2649 * @retval AVERROR(EAGAIN) output is not available in the current state - user must
2650 * try to send input
2651 * @retval AVERROR_EOF the encoder has been fully flushed, and there will be no
2652 * more output packets
2653 * @retval AVERROR(EINVAL) codec not opened, or it is a decoder
2654 * @retval "another negative error code" legitimate encoding errors
2655 */
2656int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
2657
2658/**
2659 * Create and return a AVHWFramesContext with values adequate for hardware
2660 * decoding. This is meant to get called from the get_format callback, and is
2661 * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
2662 * This API is for decoding with certain hardware acceleration modes/APIs only.
2663 *
2664 * The returned AVHWFramesContext is not initialized. The caller must do this
2665 * with av_hwframe_ctx_init().
2666 *
2667 * Calling this function is not a requirement, but makes it simpler to avoid
2668 * codec or hardware API specific details when manually allocating frames.
2669 *
2670 * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
2671 * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
2672 * it unnecessary to call this function or having to care about
2673 * AVHWFramesContext initialization at all.
2674 *
2675 * There are a number of requirements for calling this function:
2676 *
2677 * - It must be called from get_format with the same avctx parameter that was
2678 * passed to get_format. Calling it outside of get_format is not allowed, and
2679 * can trigger undefined behavior.
2680 * - The function is not always supported (see description of return values).
2681 * Even if this function returns successfully, hwaccel initialization could
2682 * fail later. (The degree to which implementations check whether the stream
2683 * is actually supported varies. Some do this check only after the user's
2684 * get_format callback returns.)
2685 * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
2686 * user decides to use a AVHWFramesContext prepared with this API function,
2687 * the user must return the same hw_pix_fmt from get_format.
2688 * - The device_ref passed to this function must support the given hw_pix_fmt.
2689 * - After calling this API function, it is the user's responsibility to
2690 * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
2691 * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
2692 * before returning from get_format (this is implied by the normal
2693 * AVCodecContext.hw_frames_ctx API rules).
2694 * - The AVHWFramesContext parameters may change every time time get_format is
2695 * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
2696 * you are inherently required to go through this process again on every
2697 * get_format call.
2698 * - It is perfectly possible to call this function without actually using
2699 * the resulting AVHWFramesContext. One use-case might be trying to reuse a
2700 * previously initialized AVHWFramesContext, and calling this API function
2701 * only to test whether the required frame parameters have changed.
2702 * - Fields that use dynamically allocated values of any kind must not be set
2703 * by the user unless setting them is explicitly allowed by the documentation.
2704 * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
2705 * the new free callback must call the potentially set previous free callback.
2706 * This API call may set any dynamically allocated fields, including the free
2707 * callback.
2708 *
2709 * The function will set at least the following fields on AVHWFramesContext
2710 * (potentially more, depending on hwaccel API):
2711 *
2712 * - All fields set by av_hwframe_ctx_alloc().
2713 * - Set the format field to hw_pix_fmt.
2714 * - Set the sw_format field to the most suited and most versatile format. (An
2715 * implication is that this will prefer generic formats over opaque formats
2716 * with arbitrary restrictions, if possible.)
2717 * - Set the width/height fields to the coded frame size, rounded up to the
2718 * API-specific minimum alignment.
2719 * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
2720 * field to the number of maximum reference surfaces possible with the codec,
2721 * plus 1 surface for the user to work (meaning the user can safely reference
2722 * at most 1 decoded surface at a time), plus additional buffering introduced
2723 * by frame threading. If the hwaccel does not require pre-allocation, the
2724 * field is left to 0, and the decoder will allocate new surfaces on demand
2725 * during decoding.
2726 * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
2727 * hardware API.
2728 *
2729 * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
2730 * with basic frame parameters set.
2731 *
2732 * The function is stateless, and does not change the AVCodecContext or the
2733 * device_ref AVHWDeviceContext.
2734 *
2735 * @param avctx The context which is currently calling get_format, and which
2736 * implicitly contains all state needed for filling the returned
2737 * AVHWFramesContext properly.
2738 * @param device_ref A reference to the AVHWDeviceContext describing the device
2739 * which will be used by the hardware decoder.
2740 * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
2741 * @param out_frames_ref On success, set to a reference to an _uninitialized_
2742 * AVHWFramesContext, created from the given device_ref.
2743 * Fields will be set to values required for decoding.
2744 * Not changed if an error is returned.
2745 * @return zero on success, a negative value on error. The following error codes
2746 * have special semantics:
2747 * AVERROR(ENOENT): the decoder does not support this functionality. Setup
2748 * is always manual, or it is a decoder which does not
2749 * support setting AVCodecContext.hw_frames_ctx at all,
2750 * or it is a software format.
2751 * AVERROR(EINVAL): it is known that hardware decoding is not supported for
2752 * this configuration, or the device_ref is not supported
2753 * for the hwaccel referenced by hw_pix_fmt.
2754 */
2755int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
2756 AVBufferRef *device_ref,
2757 enum AVPixelFormat hw_pix_fmt,
2758 AVBufferRef **out_frames_ref);
2759
2760
2761
2762/**
2763 * @defgroup lavc_parsing Frame parsing
2764 * @{
2765 */
2766
2767enum AVPictureStructure {
2768 AV_PICTURE_STRUCTURE_UNKNOWN, ///< unknown
2769 AV_PICTURE_STRUCTURE_TOP_FIELD, ///< coded as top field
2770 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, ///< coded as bottom field
2771 AV_PICTURE_STRUCTURE_FRAME, ///< coded as frame
2772};
2773
2774typedef struct AVCodecParserContext {
2775 void *priv_data;
2776 const struct AVCodecParser *parser;
2777 int64_t frame_offset; /* offset of the current frame */
2778 int64_t cur_offset; /* current offset
2779 (incremented by each av_parser_parse()) */
2780 int64_t next_frame_offset; /* offset of the next frame */
2781 /* video info */
2782 int pict_type; /* XXX: Put it back in AVCodecContext. */
2783 /**
2784 * This field is used for proper frame duration computation in lavf.
2785 * It signals, how much longer the frame duration of the current frame
2786 * is compared to normal frame duration.
2787 *
2788 * frame_duration = (1 + repeat_pict) * time_base
2789 *
2790 * It is used by codecs like H.264 to display telecined material.
2791 */
2792 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
2793 int64_t pts; /* pts of the current frame */
2794 int64_t dts; /* dts of the current frame */
2795
2796 /* private data */
2797 int64_t last_pts;
2798 int64_t last_dts;
2799 int fetch_timestamp;
2800
2801#define AV_PARSER_PTS_NB 4
2802 int cur_frame_start_index;
2803 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
2804 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
2805 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
2806
2807 int flags;
2808#define PARSER_FLAG_COMPLETE_FRAMES 0x0001
2809#define PARSER_FLAG_ONCE 0x0002
2810/// Set if the parser has a valid file offset
2811#define PARSER_FLAG_FETCHED_OFFSET 0x0004
2812#define PARSER_FLAG_USE_CODEC_TS 0x1000
2813
2814 int64_t offset; ///< byte offset from starting packet start
2815 int64_t cur_frame_end[AV_PARSER_PTS_NB];
2816
2817 /**
2818 * Set by parser to 1 for key frames and 0 for non-key frames.
2819 * It is initialized to -1, so if the parser doesn't set this flag,
2820 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
2821 * will be used.
2822 */
2823 int key_frame;
2824
2825 // Timestamp generation support:
2826 /**
2827 * Synchronization point for start of timestamp generation.
2828 *
2829 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
2830 * (default).
2831 *
2832 * For example, this corresponds to presence of H.264 buffering period
2833 * SEI message.
2834 */
2835 int dts_sync_point;
2836
2837 /**
2838 * Offset of the current timestamp against last timestamp sync point in
2839 * units of AVCodecContext.time_base.
2840 *
2841 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2842 * contain a valid timestamp offset.
2843 *
2844 * Note that the timestamp of sync point has usually a nonzero
2845 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
2846 * the next frame after timestamp sync point will be usually 1.
2847 *
2848 * For example, this corresponds to H.264 cpb_removal_delay.
2849 */
2850 int dts_ref_dts_delta;
2851
2852 /**
2853 * Presentation delay of current frame in units of AVCodecContext.time_base.
2854 *
2855 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2856 * contain valid non-negative timestamp delta (presentation time of a frame
2857 * must not lie in the past).
2858 *
2859 * This delay represents the difference between decoding and presentation
2860 * time of the frame.
2861 *
2862 * For example, this corresponds to H.264 dpb_output_delay.
2863 */
2864 int pts_dts_delta;
2865
2866 /**
2867 * Position of the packet in file.
2868 *
2869 * Analogous to cur_frame_pts/dts
2870 */
2871 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
2872
2873 /**
2874 * Byte position of currently parsed frame in stream.
2875 */
2876 int64_t pos;
2877
2878 /**
2879 * Previous frame byte position.
2880 */
2881 int64_t last_pos;
2882
2883 /**
2884 * Duration of the current frame.
2885 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
2886 * For all other types, this is in units of AVCodecContext.time_base.
2887 */
2888 int duration;
2889
2890 enum AVFieldOrder field_order;
2891
2892 /**
2893 * Indicate whether a picture is coded as a frame, top field or bottom field.
2894 *
2895 * For example, H.264 field_pic_flag equal to 0 corresponds to
2896 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
2897 * equal to 1 and bottom_field_flag equal to 0 corresponds to
2898 * AV_PICTURE_STRUCTURE_TOP_FIELD.
2899 */
2900 enum AVPictureStructure picture_structure;
2901
2902 /**
2903 * Picture number incremented in presentation or output order.
2904 * This field may be reinitialized at the first picture of a new sequence.
2905 *
2906 * For example, this corresponds to H.264 PicOrderCnt.
2907 */
2908 int output_picture_number;
2909
2910 /**
2911 * Dimensions of the decoded video intended for presentation.
2912 */
2913 int width;
2914 int height;
2915
2916 /**
2917 * Dimensions of the coded video.
2918 */
2919 int coded_width;
2920 int coded_height;
2921
2922 /**
2923 * The format of the coded data, corresponds to enum AVPixelFormat for video
2924 * and for enum AVSampleFormat for audio.
2925 *
2926 * Note that a decoder can have considerable freedom in how exactly it
2927 * decodes the data, so the format reported here might be different from the
2928 * one returned by a decoder.
2929 */
2930 int format;
2931} AVCodecParserContext;
2932
2933typedef struct AVCodecParser {
2934 int codec_ids[7]; /* several codec IDs are permitted */
2935 int priv_data_size;
2936 int (*parser_init)(AVCodecParserContext *s);
2937 /* This callback never returns an error, a negative value means that
2938 * the frame start was in a previous packet. */
2939 int (*parser_parse)(AVCodecParserContext *s,
2940 AVCodecContext *avctx,
2941 const uint8_t **poutbuf, int *poutbuf_size,
2942 const uint8_t *buf, int buf_size);
2943 void (*parser_close)(AVCodecParserContext *s);
2944 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
2945} AVCodecParser;
2946
2947/**
2948 * Iterate over all registered codec parsers.
2949 *
2950 * @param opaque a pointer where libavcodec will store the iteration state. Must
2951 * point to NULL to start the iteration.
2952 *
2953 * @return the next registered codec parser or NULL when the iteration is
2954 * finished
2955 */
2956const AVCodecParser *av_parser_iterate(void **opaque);
2957
2958AVCodecParserContext *av_parser_init(int codec_id);
2959
2960/**
2961 * Parse a packet.
2962 *
2963 * @param s parser context.
2964 * @param avctx codec context.
2965 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
2966 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
2967 * @param buf input buffer.
2968 * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
2969 size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
2970 To signal EOF, this should be 0 (so that the last frame
2971 can be output).
2972 * @param pts input presentation timestamp.
2973 * @param dts input decoding timestamp.
2974 * @param pos input byte position in stream.
2975 * @return the number of bytes of the input bitstream used.
2976 *
2977 * Example:
2978 * @code
2979 * while(in_len){
2980 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
2981 * in_data, in_len,
2982 * pts, dts, pos);
2983 * in_data += len;
2984 * in_len -= len;
2985 *
2986 * if(size)
2987 * decode_frame(data, size);
2988 * }
2989 * @endcode
2990 */
2991int av_parser_parse2(AVCodecParserContext *s,
2992 AVCodecContext *avctx,
2993 uint8_t **poutbuf, int *poutbuf_size,
2994 const uint8_t *buf, int buf_size,
2995 int64_t pts, int64_t dts,
2996 int64_t pos);
2997
2998void av_parser_close(AVCodecParserContext *s);
2999
3000/**
3001 * @}
3002 * @}
3003 */
3004
3005/**
3006 * @addtogroup lavc_encoding
3007 * @{
3008 */
3009
3010int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3011 const AVSubtitle *sub);
3012
3013
3014/**
3015 * @}
3016 */
3017
3018/**
3019 * @defgroup lavc_misc Utility functions
3020 * @ingroup libavc
3021 *
3022 * Miscellaneous utility functions related to both encoding and decoding
3023 * (or neither).
3024 * @{
3025 */
3026
3027/**
3028 * @defgroup lavc_misc_pixfmt Pixel formats
3029 *
3030 * Functions for working with pixel formats.
3031 * @{
3032 */
3033
3034/**
3035 * Return a value representing the fourCC code associated to the
3036 * pixel format pix_fmt, or 0 if no associated fourCC code can be
3037 * found.
3038 */
3039unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
3040
3041/**
3042 * Find the best pixel format to convert to given a certain source pixel
3043 * format. When converting from one pixel format to another, information loss
3044 * may occur. For example, when converting from RGB24 to GRAY, the color
3045 * information will be lost. Similarly, other losses occur when converting from
3046 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
3047 * the given pixel formats should be used to suffer the least amount of loss.
3048 * The pixel formats from which it chooses one, are determined by the
3049 * pix_fmt_list parameter.
3050 *
3051 *
3052 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
3053 * @param[in] src_pix_fmt source pixel format
3054 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
3055 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
3056 * @return The best pixel format to convert to or -1 if none was found.
3057 */
3058enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
3059 enum AVPixelFormat src_pix_fmt,
3060 int has_alpha, int *loss_ptr);
3061
3062enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
3063
3064/**
3065 * @}
3066 */
3067
3068void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
3069
3070int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
3071int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
3072//FIXME func typedef
3073
3074/**
3075 * Fill AVFrame audio data and linesize pointers.
3076 *
3077 * The buffer buf must be a preallocated buffer with a size big enough
3078 * to contain the specified samples amount. The filled AVFrame data
3079 * pointers will point to this buffer.
3080 *
3081 * AVFrame extended_data channel pointers are allocated if necessary for
3082 * planar audio.
3083 *
3084 * @param frame the AVFrame
3085 * frame->nb_samples must be set prior to calling the
3086 * function. This function fills in frame->data,
3087 * frame->extended_data, frame->linesize[0].
3088 * @param nb_channels channel count
3089 * @param sample_fmt sample format
3090 * @param buf buffer to use for frame data
3091 * @param buf_size size of buffer
3092 * @param align plane size sample alignment (0 = default)
3093 * @return >=0 on success, negative error code on failure
3094 * @todo return the size in bytes required to store the samples in
3095 * case of success, at the next libavutil bump
3096 */
3097int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
3098 enum AVSampleFormat sample_fmt, const uint8_t *buf,
3099 int buf_size, int align);
3100
3101/**
3102 * Reset the internal codec state / flush internal buffers. Should be called
3103 * e.g. when seeking or when switching to a different stream.
3104 *
3105 * @note for decoders, this function just releases any references the decoder
3106 * might keep internally, but the caller's references remain valid.
3107 *
3108 * @note for encoders, this function will only do something if the encoder
3109 * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3110 * will drain any remaining packets, and can then be re-used for a different
3111 * stream (as opposed to sending a null frame which will leave the encoder
3112 * in a permanent EOF state after draining). This can be desirable if the
3113 * cost of tearing down and replacing the encoder instance is high.
3114 */
3115void avcodec_flush_buffers(AVCodecContext *avctx);
3116
3117/**
3118 * Return audio frame duration.
3119 *
3120 * @param avctx codec context
3121 * @param frame_bytes size of the frame, or 0 if unknown
3122 * @return frame duration, in samples, if known. 0 if not able to
3123 * determine.
3124 */
3125int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
3126
3127/* memory */
3128
3129/**
3130 * Same behaviour av_fast_malloc but the buffer has additional
3131 * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
3132 *
3133 * In addition the whole buffer will initially and after resizes
3134 * be 0-initialized so that no uninitialized data will ever appear.
3135 */
3136void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
3137
3138/**
3139 * Same behaviour av_fast_padded_malloc except that buffer will always
3140 * be 0-initialized after call.
3141 */
3142void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
3143
3144/**
3145 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
3146 * with no corresponding avcodec_close()), 0 otherwise.
3147 */
3148int avcodec_is_open(AVCodecContext *s);
3149
3150/**
3151 * @}
3152 */
3153
3154#endif /* AVCODEC_AVCODEC_H */
3155