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 <errno.h>
31	#include "libavutil/samplefmt.h"
32	#include "libavutil/attributes.h"
33	#include "libavutil/avutil.h"
34	#include "libavutil/buffer.h"
35	#include "libavutil/cpu.h"
36	#include "libavutil/channel_layout.h"
37	#include "libavutil/dict.h"
38	#include "libavutil/frame.h"
39	#include "libavutil/hwcontext.h"
40	#include "libavutil/log.h"
41	#include "libavutil/pixfmt.h"
42	#include "libavutil/rational.h"
43
44	#include "bsf.h"
45	#include "codec.h"
46	#include "codec_desc.h"
47	#include "codec_par.h"
48	#include "codec_id.h"
49	#include "packet.h"
50	#include "version.h"
51
52	/**
53	* @defgroup libavc libavcodec
54	* Encoding/Decoding Library
55	*
56	* @{
57	*
58	* @defgroup lavc_decoding Decoding
59	* @{
60	* @}
61	*
62	* @defgroup lavc_encoding Encoding
63	* @{
64	* @}
65	*
66	* @defgroup lavc_codec Codecs
67	* @{
68	* @defgroup lavc_codec_native Native Codecs
69	* @{
70	* @}
71	* @defgroup lavc_codec_wrappers External library wrappers
72	* @{
73	* @}
74	* @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
75	* @{
76	* @}
77	* @}
78	* @defgroup lavc_internal Internal
79	* @{
80	* @}
81	* @}
82	*/
83
84	/**
85	* @ingroup libavc
86	* @defgroup lavc_encdec send/receive encoding and decoding API overview
87	* @{
88	*
89	* The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
90	* avcodec_receive_packet() functions provide an encode/decode API, which
91	* decouples input and output.
92	*
93	* The API is very similar for encoding/decoding and audio/video, and works as
94	* follows:
95	* - Set up and open the AVCodecContext as usual.
96	* - Send valid input:
97	* - For decoding, call avcodec_send_packet() to give the decoder raw
98	* compressed data in an AVPacket.
99	* - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
100	* containing uncompressed audio or video.
101	*
102	* In both cases, it is recommended that AVPackets and AVFrames are
103	* refcounted, or libavcodec might have to copy the input data. (libavformat
104	* always returns refcounted AVPackets, and av_frame_get_buffer() allocates
105	* refcounted AVFrames.)
106	* - Receive output in a loop. Periodically call one of the avcodec_receive_*()
107	* functions and process their output:
108	* - For decoding, call avcodec_receive_frame(). On success, it will return
109	* an AVFrame containing uncompressed audio or video data.
110	* - For encoding, call avcodec_receive_packet(). On success, it will return
111	* an AVPacket with a compressed frame.
112	*
113	* Repeat this call until it returns AVERROR(EAGAIN) or an error. The
114	* AVERROR(EAGAIN) return value means that new input data is required to
115	* return new output. In this case, continue with sending input. For each
116	* input frame/packet, the codec will typically return 1 output frame/packet,
117	* but it can also be 0 or more than 1.
118	*
119	* At the beginning of decoding or encoding, the codec might accept multiple
120	* input frames/packets without returning a frame, until its internal buffers
121	* are filled. This situation is handled transparently if you follow the steps
122	* outlined above.
123	*
124	* In theory, sending input can result in EAGAIN - this should happen only if
125	* not all output was received. You can use this to structure alternative decode
126	* or encode loops other than the one suggested above. For example, you could
127	* try sending new input on each iteration, and try to receive output if that
128	* returns EAGAIN.
129	*
130	* End of stream situations. These require "flushing" (aka draining) the codec,
131	* as the codec might buffer multiple frames or packets internally for
132	* performance or out of necessity (consider B-frames).
133	* This is handled as follows:
134	* - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
135	* or avcodec_send_frame() (encoding) functions. This will enter draining
136	* mode.
137	* - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
138	* (encoding) in a loop until AVERROR_EOF is returned. The functions will
139	* not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
140	* - Before decoding can be resumed again, the codec has to be reset with
141	* avcodec_flush_buffers().
142	*
143	* Using the API as outlined above is highly recommended. But it is also
144	* possible to call functions outside of this rigid schema. For example, you can
145	* call avcodec_send_packet() repeatedly without calling
146	* avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
147	* until the codec's internal buffer has been filled up (which is typically of
148	* size 1 per output frame, after initial input), and then reject input with
149	* AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
150	* read at least some output.
151	*
152	* Not all codecs will follow a rigid and predictable dataflow; the only
153	* guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
154	* one end implies that a receive/send call on the other end will succeed, or
155	* at least will not fail with AVERROR(EAGAIN). In general, no codec will
156	* permit unlimited buffering of input or output.
157	*
158	* This API replaces the following legacy functions:
159	* - avcodec_decode_video2() and avcodec_decode_audio4():
160	* Use avcodec_send_packet() to feed input to the decoder, then use
161	* avcodec_receive_frame() to receive decoded frames after each packet.
162	* Unlike with the old video decoding API, multiple frames might result from
163	* a packet. For audio, splitting the input packet into frames by partially
164	* decoding packets becomes transparent to the API user. You never need to
165	* feed an AVPacket to the API twice (unless it is rejected with AVERROR(EAGAIN) - then
166	* no data was read from the packet).
167	* Additionally, sending a flush/draining packet is required only once.
168	* - avcodec_encode_video2()/avcodec_encode_audio2():
169	* Use avcodec_send_frame() to feed input to the encoder, then use
170	* avcodec_receive_packet() to receive encoded packets.
171	* Providing user-allocated buffers for avcodec_receive_packet() is not
172	* possible.
173	* - The new API does not handle subtitles yet.
174	*
175	* Mixing new and old function calls on the same AVCodecContext is not allowed,
176	* and will result in undefined behavior.
177	*
178	* Some codecs might require using the new API; using the old API will return
179	* an error when calling it. All codecs support the new API.
180	*
181	* A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
182	* would be an invalid state, which could put the codec user into an endless
183	* loop. The API has no concept of time either: it cannot happen that trying to
184	* do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
185	* later accepts the packet (with no other receive/flush API calls involved).
186	* The API is a strict state machine, and the passage of time is not supposed
187	* to influence it. Some timing-dependent behavior might still be deemed
188	* acceptable in certain cases. But it must never result in both send/receive
189	* returning EAGAIN at the same time at any point. It must also absolutely be
190	* avoided that the current state is "unstable" and can "flip-flop" between
191	* the send/receive APIs allowing progress. For example, it's not allowed that
192	* the codec randomly decides that it actually wants to consume a packet now
193	* instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
194	* avcodec_send_packet() call.
195	* @}
196	*/
197
198	/**
199	* @defgroup lavc_core Core functions/structures.
200	* @ingroup libavc
201	*
202	* Basic definitions, functions for querying libavcodec capabilities,
203	* allocating core structures, etc.
204	* @{
205	*/
206
207	/**
208	* @ingroup lavc_decoding
209	* Required number of additionally allocated bytes at the end of the input bitstream for decoding.
210	* This is mainly needed because some optimized bitstream readers read
211	* 32 or 64 bit at once and could read over the end.<br>
212	* Note: If the first 23 bits of the additional bytes are not 0, then damaged
213	* MPEG bitstreams could cause overread and segfault.
214	*/
215	#define AV_INPUT_BUFFER_PADDING_SIZE 64
216
217	/**
218	* @ingroup lavc_encoding
219	* minimum encoding buffer size
220	* Used to avoid some checks during header writing.
221	*/
222	#define AV_INPUT_BUFFER_MIN_SIZE 16384
223
224	/**
225	* @ingroup lavc_decoding
226	*/
227	enum AVDiscard{
228	/* We leave some space between them for extensions (drop some
229	* keyframes for intra-only or drop just some bidir frames). */
230	AVDISCARD_NONE =-16, ///< discard nothing
231	AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
232	AVDISCARD_NONREF = 8, ///< discard all non reference
233	AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
234	AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
235	AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
236	AVDISCARD_ALL = 48, ///< discard all
237	};
238
239	enum AVAudioServiceType {
240	AV_AUDIO_SERVICE_TYPE_MAIN = 0,
241	AV_AUDIO_SERVICE_TYPE_EFFECTS = 1,
242	AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
243	AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED = 3,
244	AV_AUDIO_SERVICE_TYPE_DIALOGUE = 4,
245	AV_AUDIO_SERVICE_TYPE_COMMENTARY = 5,
246	AV_AUDIO_SERVICE_TYPE_EMERGENCY = 6,
247	AV_AUDIO_SERVICE_TYPE_VOICE_OVER = 7,
248	AV_AUDIO_SERVICE_TYPE_KARAOKE = 8,
249	AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
250	};
251
252	/**
253	* @ingroup lavc_encoding
254	*/
255	typedef struct RcOverride{
256	int start_frame;
257	int end_frame;
258	int qscale; // If this is 0 then quality_factor will be used instead.
259	float quality_factor;
260	} RcOverride;
261
262	/* encoding support
263	These flags can be passed in AVCodecContext.flags before initialization.
264	Note: Not everything is supported yet.
265	*/
266
267	/**
268	* Allow decoders to produce frames with data planes that are not aligned
269	* to CPU requirements (e.g. due to cropping).
270	*/
271	#define AV_CODEC_FLAG_UNALIGNED (1 << 0)
272	/**
273	* Use fixed qscale.
274	*/
275	#define AV_CODEC_FLAG_QSCALE (1 << 1)
276	/**
277	* 4 MV per MB allowed / advanced prediction for H.263.
278	*/
279	#define AV_CODEC_FLAG_4MV (1 << 2)
280	/**
281	* Output even those frames that might be corrupted.
282	*/
283	#define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
284	/**
285	* Use qpel MC.
286	*/
287	#define AV_CODEC_FLAG_QPEL (1 << 4)
288	/**
289	* Don't output frames whose parameters differ from first
290	* decoded frame in stream.
291	*/
292	#define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
293	/**
294	* Use internal 2pass ratecontrol in first pass mode.
295	*/
296	#define AV_CODEC_FLAG_PASS1 (1 << 9)
297	/**
298	* Use internal 2pass ratecontrol in second pass mode.
299	*/
300	#define AV_CODEC_FLAG_PASS2 (1 << 10)
301	/**
302	* loop filter.
303	*/
304	#define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
305	/**
306	* Only decode/encode grayscale.
307	*/
308	#define AV_CODEC_FLAG_GRAY (1 << 13)
309	/**
310	* error[?] variables will be set during encoding.
311	*/
312	#define AV_CODEC_FLAG_PSNR (1 << 15)
313	/**
314	* Input bitstream might be truncated at a random location
315	* instead of only at frame boundaries.
316	*/
317	#define AV_CODEC_FLAG_TRUNCATED (1 << 16)
318	/**
319	* Use interlaced DCT.
320	*/
321	#define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
322	/**
323	* Force low delay.
324	*/
325	#define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
326	/**
327	* Place global headers in extradata instead of every keyframe.
328	*/
329	#define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
330	/**
331	* Use only bitexact stuff (except (I)DCT).
332	*/
333	#define AV_CODEC_FLAG_BITEXACT (1 << 23)
334	/* Fx : Flag for H.263+ extra options */
335	/**
336	* H.263 advanced intra coding / MPEG-4 AC prediction
337	*/
338	#define AV_CODEC_FLAG_AC_PRED (1 << 24)
339	/**
340	* interlaced motion estimation
341	*/
342	#define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
343	#define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
344
345	/**
346	* Allow non spec compliant speedup tricks.
347	*/
348	#define AV_CODEC_FLAG2_FAST (1 << 0)
349	/**
350	* Skip bitstream encoding.
351	*/
352	#define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
353	/**
354	* Place global headers at every keyframe instead of in extradata.
355	*/
356	#define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
357
358	/**
359	* timecode is in drop frame format. DEPRECATED!!!!
360	*/
361	#define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
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	/* Unsupported options :
391	* Syntax Arithmetic coding (SAC)
392	* Reference Picture Selection
393	* Independent Segment Decoding */
394	/* /Fx */
395	/* codec capabilities */
396
397	/* Exported side data.
398	These flags can be passed in AVCodecContext.export_side_data before initialization.
399	*/
400	/**
401	* Export motion vectors through frame side data
402	*/
403	#define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
404	/**
405	* Export encoder Producer Reference Time through packet side data
406	*/
407	#define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
408	/**
409	* Decoding only.
410	* Export the AVVideoEncParams structure through frame side data.
411	*/
412	#define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
413	/**
414	* Decoding only.
415	* Do not apply film grain, export it instead.
416	*/
417	#define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
418
419	/**
420	* Pan Scan area.
421	* This specifies the area which should be displayed.
422	* Note there may be multiple such areas for one frame.
423	*/
424	typedef struct AVPanScan {
425	/**
426	* id
427	* - encoding: Set by user.
428	* - decoding: Set by libavcodec.
429	*/
430	int id;
431
432	/**
433	* width and height in 1/16 pel
434	* - encoding: Set by user.
435	* - decoding: Set by libavcodec.
436	*/
437	int width;
438	int height;
439
440	/**
441	* position of the top left corner in 1/16 pel for up to 3 fields/frames
442	* - encoding: Set by user.
443	* - decoding: Set by libavcodec.
444	*/
445	int16_t position[3][2];
446	} AVPanScan;
447
448	/**
449	* This structure describes the bitrate properties of an encoded bitstream. It
450	* roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
451	* parameters for H.264/HEVC.
452	*/
453	typedef struct AVCPBProperties {
454	/**
455	* Maximum bitrate of the stream, in bits per second.
456	* Zero if unknown or unspecified.
457	*/
458	#if FF_API_UNSANITIZED_BITRATES
459	int max_bitrate;
460	#else
461	int64_t max_bitrate;
462	#endif
463	/**
464	* Minimum bitrate of the stream, in bits per second.
465	* Zero if unknown or unspecified.
466	*/
467	#if FF_API_UNSANITIZED_BITRATES
468	int min_bitrate;
469	#else
470	int64_t min_bitrate;
471	#endif
472	/**
473	* Average bitrate of the stream, in bits per second.
474	* Zero if unknown or unspecified.
475	*/
476	#if FF_API_UNSANITIZED_BITRATES
477	int avg_bitrate;
478	#else
479	int64_t avg_bitrate;
480	#endif
481
482	/**
483	* The size of the buffer to which the ratecontrol is applied, in bits.
484	* Zero if unknown or unspecified.
485	*/
486	int buffer_size;
487
488	/**
489	* The delay between the time the packet this structure is associated with
490	* is received and the time when it should be decoded, in periods of a 27MHz
491	* clock.
492	*
493	* UINT64_MAX when unknown or unspecified.
494	*/
495	uint64_t vbv_delay;
496	} AVCPBProperties;
497
498	/**
499	* This structure supplies correlation between a packet timestamp and a wall clock
500	* production time. The definition follows the Producer Reference Time ('prft')
501	* as defined in ISO/IEC 14496-12
502	*/
503	typedef struct AVProducerReferenceTime {
504	/**
505	* A UTC timestamp, in microseconds, since Unix epoch (e.g, av_gettime()).
506	*/
507	int64_t wallclock;
508	int flags;
509	} AVProducerReferenceTime;
510
511	/**
512	* The decoder will keep a reference to the frame and may reuse it later.
513	*/
514	#define AV_GET_BUFFER_FLAG_REF (1 << 0)
515
516	/**
517	* The encoder will keep a reference to the packet and may reuse it later.
518	*/
519	#define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
520
521	struct AVCodecInternal;
522
523	/**
524	* main external API structure.
525	* New fields can be added to the end with minor version bumps.
526	* Removal, reordering and changes to existing fields require a major
527	* version bump.
528	* You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
529	* applications.
530	* The name string for AVOptions options matches the associated command line
531	* parameter name and can be found in libavcodec/options_table.h
532	* The AVOption/command line parameter names differ in some cases from the C
533	* structure field names for historic reasons or brevity.
534	* sizeof(AVCodecContext) must not be used outside libav*.
535	*/
536	typedef struct AVCodecContext {
537	/**
538	* information on struct for av_log
539	* - set by avcodec_alloc_context3
540	*/
541	const AVClass *av_class;
542	int log_level_offset;
543
544	enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
545	const struct AVCodec *codec;
546	enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
547
548	/**
549	* fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
550	* This is used to work around some encoder bugs.
551	* A demuxer should set this to what is stored in the field used to identify the codec.
552	* If there are multiple such fields in a container then the demuxer should choose the one
553	* which maximizes the information about the used codec.
554	* If the codec tag field in a container is larger than 32 bits then the demuxer should
555	* remap the longer ID to 32 bits with a table or other structure. Alternatively a new
556	* extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
557	* first.
558	* - encoding: Set by user, if not then the default based on codec_id will be used.
559	* - decoding: Set by user, will be converted to uppercase by libavcodec during init.
560	*/
561	unsigned int codec_tag;
562
563	void *priv_data;
564
565	/**
566	* Private context used for internal data.
567	*
568	* Unlike priv_data, this is not codec-specific. It is used in general
569	* libavcodec functions.
570	*/
571	struct AVCodecInternal *internal;
572
573	/**
574	* Private data of the user, can be used to carry app specific stuff.
575	* - encoding: Set by user.
576	* - decoding: Set by user.
577	*/
578	void *opaque;
579
580	/**
581	* the average bitrate
582	* - encoding: Set by user; unused for constant quantizer encoding.
583	* - decoding: Set by user, may be overwritten by libavcodec
584	* if this info is available in the stream
585	*/
586	int64_t bit_rate;
587
588	/**
589	* number of bits the bitstream is allowed to diverge from the reference.
590	* the reference can be CBR (for CBR pass1) or VBR (for pass2)
591	* - encoding: Set by user; unused for constant quantizer encoding.
592	* - decoding: unused
593	*/
594	int bit_rate_tolerance;
595
596	/**
597	* Global quality for codecs which cannot change it per frame.
598	* This should be proportional to MPEG-1/2/4 qscale.
599	* - encoding: Set by user.
600	* - decoding: unused
601	*/
602	int global_quality;
603
604	/**
605	* - encoding: Set by user.
606	* - decoding: unused
607	*/
608	int compression_level;
609	#define FF_COMPRESSION_DEFAULT -1
610
611	/**
612	* AV_CODEC_FLAG_*.
613	* - encoding: Set by user.
614	* - decoding: Set by user.
615	*/
616	int flags;
617
618	/**
619	* AV_CODEC_FLAG2_*
620	* - encoding: Set by user.
621	* - decoding: Set by user.
622	*/
623	int flags2;
624
625	/**
626	* some codecs need / can use extradata like Huffman tables.
627	* MJPEG: Huffman tables
628	* rv10: additional flags
629	* MPEG-4: global headers (they can be in the bitstream or here)
630	* The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
631	* than extradata_size to avoid problems if it is read with the bitstream reader.
632	* The bytewise contents of extradata must not depend on the architecture or CPU endianness.
633	* Must be allocated with the av_malloc() family of functions.
634	* - encoding: Set/allocated/freed by libavcodec.
635	* - decoding: Set/allocated/freed by user.
636	*/
637	uint8_t *extradata;
638	int extradata_size;
639
640	/**
641	* This is the fundamental unit of time (in seconds) in terms
642	* of which frame timestamps are represented. For fixed-fps content,
643	* timebase should be 1/framerate and timestamp increments should be
644	* identically 1.
645	* This often, but not always is the inverse of the frame rate or field rate
646	* for video. 1/time_base is not the average frame rate if the frame rate is not
647	* constant.
648	*
649	* Like containers, elementary streams also can store timestamps, 1/time_base
650	* is the unit in which these timestamps are specified.
651	* As example of such codec time base see ISO/IEC 14496-2:2001(E)
652	* vop_time_increment_resolution and fixed_vop_rate
653	* (fixed_vop_rate == 0 implies that it is different from the framerate)
654	*
655	* - encoding: MUST be set by user.
656	* - decoding: the use of this field for decoding is deprecated.
657	* Use framerate instead.
658	*/
659	AVRational time_base;
660
661	/**
662	* For some codecs, the time base is closer to the field rate than the frame rate.
663	* Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
664	* if no telecine is used ...
665	*
666	* Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
667	*/
668	int ticks_per_frame;
669
670	/**
671	* Codec delay.
672	*
673	* Encoding: Number of frames delay there will be from the encoder input to
674	* the decoder output. (we assume the decoder matches the spec)
675	* Decoding: Number of frames delay in addition to what a standard decoder
676	* as specified in the spec would produce.
677	*
678	* Video:
679	* Number of frames the decoded output will be delayed relative to the
680	* encoded input.
681	*
682	* Audio:
683	* For encoding, this field is unused (see initial_padding).
684	*
685	* For decoding, this is the number of samples the decoder needs to
686	* output before the decoder's output is valid. When seeking, you should
687	* start decoding this many samples prior to your desired seek point.
688	*
689	* - encoding: Set by libavcodec.
690	* - decoding: Set by libavcodec.
691	*/
692	int delay;
693
694
695	/* video only */
696	/**
697	* picture width / height.
698	*
699	* @note Those fields may not match the values of the last
700	* AVFrame output by avcodec_decode_video2 due frame
701	* reordering.
702	*
703	* - encoding: MUST be set by user.
704	* - decoding: May be set by the user before opening the decoder if known e.g.
705	* from the container. Some decoders will require the dimensions
706	* to be set by the caller. During decoding, the decoder may
707	* overwrite those values as required while parsing the data.
708	*/
709	int width, height;
710
711	/**
712	* Bitstream width / height, may be different from width/height e.g. when
713	* the decoded frame is cropped before being output or lowres is enabled.
714	*
715	* @note Those field may not match the value of the last
716	* AVFrame output by avcodec_receive_frame() due frame
717	* reordering.
718	*
719	* - encoding: unused
720	* - decoding: May be set by the user before opening the decoder if known
721	* e.g. from the container. During decoding, the decoder may
722	* overwrite those values as required while parsing the data.
723	*/
724	int coded_width, coded_height;
725
726	/**
727	* the number of pictures in a group of pictures, or 0 for intra_only
728	* - encoding: Set by user.
729	* - decoding: unused
730	*/
731	int gop_size;
732
733	/**
734	* Pixel format, see AV_PIX_FMT_xxx.
735	* May be set by the demuxer if known from headers.
736	* May be overridden by the decoder if it knows better.
737	*
738	* @note This field may not match the value of the last
739	* AVFrame output by avcodec_receive_frame() due frame
740	* reordering.
741	*
742	* - encoding: Set by user.
743	* - decoding: Set by user if known, overridden by libavcodec while
744	* parsing the data.
745	*/
746	enum AVPixelFormat pix_fmt;
747
748	/**
749	* If non NULL, 'draw_horiz_band' is called by the libavcodec
750	* decoder to draw a horizontal band. It improves cache usage. Not
751	* all codecs can do that. You must check the codec capabilities
752	* beforehand.
753	* When multithreading is used, it may be called from multiple threads
754	* at the same time; threads might draw different parts of the same AVFrame,
755	* or multiple AVFrames, and there is no guarantee that slices will be drawn
756	* in order.
757	* The function is also used by hardware acceleration APIs.
758	* It is called at least once during frame decoding to pass
759	* the data needed for hardware render.
760	* In that mode instead of pixel data, AVFrame points to
761	* a structure specific to the acceleration API. The application
762	* reads the structure and can change some fields to indicate progress
763	* or mark state.
764	* - encoding: unused
765	* - decoding: Set by user.
766	* @param height the height of the slice
767	* @param y the y position of the slice
768	* @param type 1->top field, 2->bottom field, 3->frame
769	* @param offset offset into the AVFrame.data from which the slice should be read
770	*/
771	void (*draw_horiz_band)(struct AVCodecContext *s,
772	const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
773	int y, int type, int height);
774
775	/**
776	* callback to negotiate the pixelFormat
777	* @param fmt is the list of formats which are supported by the codec,
778	* it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
779	* The first is always the native one.
780	* @note The callback may be called again immediately if initialization for
781	* the selected (hardware-accelerated) pixel format failed.
782	* @warning Behavior is undefined if the callback returns a value not
783	* in the fmt list of formats.
784	* @return the chosen format
785	* - encoding: unused
786	* - decoding: Set by user, if not set the native format will be chosen.
787	*/
788	enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
789
790	/**
791	* maximum number of B-frames between non-B-frames
792	* Note: The output will be delayed by max_b_frames+1 relative to the input.
793	* - encoding: Set by user.
794	* - decoding: unused
795	*/
796	int max_b_frames;
797
798	/**
799	* qscale factor between IP and B-frames
800	* If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
801	* If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
802	* - encoding: Set by user.
803	* - decoding: unused
804	*/
805	float b_quant_factor;
806
807	#if FF_API_PRIVATE_OPT
808	/** @deprecated use encoder private options instead */
809	attribute_deprecated
810	int b_frame_strategy;
811	#endif
812
813	/**
814	* qscale offset between IP and B-frames
815	* - encoding: Set by user.
816	* - decoding: unused
817	*/
818	float b_quant_offset;
819
820	/**
821	* Size of the frame reordering buffer in the decoder.
822	* For MPEG-2 it is 1 IPB or 0 low delay IP.
823	* - encoding: Set by libavcodec.
824	* - decoding: Set by libavcodec.
825	*/
826	int has_b_frames;
827
828	#if FF_API_PRIVATE_OPT
829	/** @deprecated use encoder private options instead */
830	attribute_deprecated
831	int mpeg_quant;
832	#endif
833
834	/**
835	* qscale factor between P- and I-frames
836	* If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
837	* If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
838	* - encoding: Set by user.
839	* - decoding: unused
840	*/
841	float i_quant_factor;
842
843	/**
844	* qscale offset between P and I-frames
845	* - encoding: Set by user.
846	* - decoding: unused
847	*/
848	float i_quant_offset;
849
850	/**
851	* luminance masking (0-> disabled)
852	* - encoding: Set by user.
853	* - decoding: unused
854	*/
855	float lumi_masking;
856
857	/**
858	* temporary complexity masking (0-> disabled)
859	* - encoding: Set by user.
860	* - decoding: unused
861	*/
862	float temporal_cplx_masking;
863
864	/**
865	* spatial complexity masking (0-> disabled)
866	* - encoding: Set by user.
867	* - decoding: unused
868	*/
869	float spatial_cplx_masking;
870
871	/**
872	* p block masking (0-> disabled)
873	* - encoding: Set by user.
874	* - decoding: unused
875	*/
876	float p_masking;
877
878	/**
879	* darkness masking (0-> disabled)
880	* - encoding: Set by user.
881	* - decoding: unused
882	*/
883	float dark_masking;
884
885	/**
886	* slice count
887	* - encoding: Set by libavcodec.
888	* - decoding: Set by user (or 0).
889	*/
890	int slice_count;
891
892	#if FF_API_PRIVATE_OPT
893	/** @deprecated use encoder private options instead */
894	attribute_deprecated
895	int prediction_method;
896	#define FF_PRED_LEFT 0
897	#define FF_PRED_PLANE 1
898	#define FF_PRED_MEDIAN 2
899	#endif
900
901	/**
902	* slice offsets in the frame in bytes
903	* - encoding: Set/allocated by libavcodec.
904	* - decoding: Set/allocated by user (or NULL).
905	*/
906	int *slice_offset;
907
908	/**
909	* sample aspect ratio (0 if unknown)
910	* That is the width of a pixel divided by the height of the pixel.
911	* Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
912	* - encoding: Set by user.
913	* - decoding: Set by libavcodec.
914	*/
915	AVRational sample_aspect_ratio;
916
917	/**
918	* motion estimation comparison function
919	* - encoding: Set by user.
920	* - decoding: unused
921	*/
922	int me_cmp;
923	/**
924	* subpixel motion estimation comparison function
925	* - encoding: Set by user.
926	* - decoding: unused
927	*/
928	int me_sub_cmp;
929	/**
930	* macroblock comparison function (not supported yet)
931	* - encoding: Set by user.
932	* - decoding: unused
933	*/
934	int mb_cmp;
935	/**
936	* interlaced DCT comparison function
937	* - encoding: Set by user.
938	* - decoding: unused
939	*/
940	int ildct_cmp;
941	#define FF_CMP_SAD 0
942	#define FF_CMP_SSE 1
943	#define FF_CMP_SATD 2
944	#define FF_CMP_DCT 3
945	#define FF_CMP_PSNR 4
946	#define FF_CMP_BIT 5
947	#define FF_CMP_RD 6
948	#define FF_CMP_ZERO 7
949	#define FF_CMP_VSAD 8
950	#define FF_CMP_VSSE 9
951	#define FF_CMP_NSSE 10
952	#define FF_CMP_W53 11
953	#define FF_CMP_W97 12
954	#define FF_CMP_DCTMAX 13
955	#define FF_CMP_DCT264 14
956	#define FF_CMP_MEDIAN_SAD 15
957	#define FF_CMP_CHROMA 256
958
959	/**
960	* ME diamond size & shape
961	* - encoding: Set by user.
962	* - decoding: unused
963	*/
964	int dia_size;
965
966	/**
967	* amount of previous MV predictors (2a+1 x 2a+1 square)
968	* - encoding: Set by user.
969	* - decoding: unused
970	*/
971	int last_predictor_count;
972
973	#if FF_API_PRIVATE_OPT
974	/** @deprecated use encoder private options instead */
975	attribute_deprecated
976	int pre_me;
977	#endif
978
979	/**
980	* motion estimation prepass comparison function
981	* - encoding: Set by user.
982	* - decoding: unused
983	*/
984	int me_pre_cmp;
985
986	/**
987	* ME prepass diamond size & shape
988	* - encoding: Set by user.
989	* - decoding: unused
990	*/
991	int pre_dia_size;
992
993	/**
994	* subpel ME quality
995	* - encoding: Set by user.
996	* - decoding: unused
997	*/
998	int me_subpel_quality;
999
1000	/**
1001	* maximum motion estimation search range in subpel units
1002	* If 0 then no limit.
1003	*
1004	* - encoding: Set by user.
1005	* - decoding: unused
1006	*/
1007	int me_range;
1008
1009	/**
1010	* slice flags
1011	* - encoding: unused
1012	* - decoding: Set by user.
1013	*/
1014	int slice_flags;
1015	#define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1016	#define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
1017	#define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1018
1019	/**
1020	* macroblock decision mode
1021	* - encoding: Set by user.
1022	* - decoding: unused
1023	*/
1024	int mb_decision;
1025	#define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1026	#define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1027	#define FF_MB_DECISION_RD 2 ///< rate distortion
1028
1029	/**
1030	* custom intra quantization matrix
1031	* Must be allocated with the av_malloc() family of functions, and will be freed in
1032	* avcodec_free_context().
1033	* - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
1034	* - decoding: Set/allocated/freed by libavcodec.
1035	*/
1036	uint16_t *intra_matrix;
1037
1038	/**
1039	* custom inter quantization matrix
1040	* Must be allocated with the av_malloc() family of functions, and will be freed in
1041	* avcodec_free_context().
1042	* - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
1043	* - decoding: Set/allocated/freed by libavcodec.
1044	*/
1045	uint16_t *inter_matrix;
1046
1047	#if FF_API_PRIVATE_OPT
1048	/** @deprecated use encoder private options instead */
1049	attribute_deprecated
1050	int scenechange_threshold;
1051
1052	/** @deprecated use encoder private options instead */
1053	attribute_deprecated
1054	int noise_reduction;
1055	#endif
1056
1057	/**
1058	* precision of the intra DC coefficient - 8
1059	* - encoding: Set by user.
1060	* - decoding: Set by libavcodec
1061	*/
1062	int intra_dc_precision;
1063
1064	/**
1065	* Number of macroblock rows at the top which are skipped.
1066	* - encoding: unused
1067	* - decoding: Set by user.
1068	*/
1069	int skip_top;
1070
1071	/**
1072	* Number of macroblock rows at the bottom which are skipped.
1073	* - encoding: unused
1074	* - decoding: Set by user.
1075	*/
1076	int skip_bottom;
1077
1078	/**
1079	* minimum MB Lagrange multiplier
1080	* - encoding: Set by user.
1081	* - decoding: unused
1082	*/
1083	int mb_lmin;
1084
1085	/**
1086	* maximum MB Lagrange multiplier
1087	* - encoding: Set by user.
1088	* - decoding: unused
1089	*/
1090	int mb_lmax;
1091
1092	#if FF_API_PRIVATE_OPT
1093	/**
1094	* @deprecated use encoder private options instead
1095	*/
1096	attribute_deprecated
1097	int me_penalty_compensation;
1098	#endif
1099
1100	/**
1101	* - encoding: Set by user.
1102	* - decoding: unused
1103	*/
1104	int bidir_refine;
1105
1106	#if FF_API_PRIVATE_OPT
1107	/** @deprecated use encoder private options instead */
1108	attribute_deprecated
1109	int brd_scale;
1110	#endif
1111
1112	/**
1113	* minimum GOP size
1114	* - encoding: Set by user.
1115	* - decoding: unused
1116	*/
1117	int keyint_min;
1118
1119	/**
1120	* number of reference frames
1121	* - encoding: Set by user.
1122	* - decoding: Set by lavc.
1123	*/
1124	int refs;
1125
1126	#if FF_API_PRIVATE_OPT
1127	/** @deprecated use encoder private options instead */
1128	attribute_deprecated
1129	int chromaoffset;
1130	#endif
1131
1132	/**
1133	* Note: Value depends upon the compare function used for fullpel ME.
1134	* - encoding: Set by user.
1135	* - decoding: unused
1136	*/
1137	int mv0_threshold;
1138
1139	#if FF_API_PRIVATE_OPT
1140	/** @deprecated use encoder private options instead */
1141	attribute_deprecated
1142	int b_sensitivity;
1143	#endif
1144
1145	/**
1146	* Chromaticity coordinates of the source primaries.
1147	* - encoding: Set by user
1148	* - decoding: Set by libavcodec
1149	*/
1150	enum AVColorPrimaries color_primaries;
1151
1152	/**
1153	* Color Transfer Characteristic.
1154	* - encoding: Set by user
1155	* - decoding: Set by libavcodec
1156	*/
1157	enum AVColorTransferCharacteristic color_trc;
1158
1159	/**
1160	* YUV colorspace type.
1161	* - encoding: Set by user
1162	* - decoding: Set by libavcodec
1163	*/
1164	enum AVColorSpace colorspace;
1165
1166	/**
1167	* MPEG vs JPEG YUV range.
1168	* - encoding: Set by user
1169	* - decoding: Set by libavcodec
1170	*/
1171	enum AVColorRange color_range;
1172
1173	/**
1174	* This defines the location of chroma samples.
1175	* - encoding: Set by user
1176	* - decoding: Set by libavcodec
1177	*/
1178	enum AVChromaLocation chroma_sample_location;
1179
1180	/**
1181	* Number of slices.
1182	* Indicates number of picture subdivisions. Used for parallelized
1183	* decoding.
1184	* - encoding: Set by user
1185	* - decoding: unused
1186	*/
1187	int slices;
1188
1189	/** Field order
1190	* - encoding: set by libavcodec
1191	* - decoding: Set by user.
1192	*/
1193	enum AVFieldOrder field_order;
1194
1195	/* audio only */
1196	int sample_rate; ///< samples per second
1197	int channels; ///< number of audio channels
1198
1199	/**
1200	* audio sample format
1201	* - encoding: Set by user.
1202	* - decoding: Set by libavcodec.
1203	*/
1204	enum AVSampleFormat sample_fmt; ///< sample format
1205
1206	/* The following data should not be initialized. */
1207	/**
1208	* Number of samples per channel in an audio frame.
1209	*
1210	* - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1211	* except the last must contain exactly frame_size samples per channel.
1212	* May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1213	* frame size is not restricted.
1214	* - decoding: may be set by some decoders to indicate constant frame size
1215	*/
1216	int frame_size;
1217
1218	/**
1219	* Frame counter, set by libavcodec.
1220	*
1221	* - decoding: total number of frames returned from the decoder so far.
1222	* - encoding: total number of frames passed to the encoder so far.
1223	*
1224	* @note the counter is not incremented if encoding/decoding resulted in
1225	* an error.
1226	*/
1227	int frame_number;
1228
1229	/**
1230	* number of bytes per packet if constant and known or 0
1231	* Used by some WAV based audio codecs.
1232	*/
1233	int block_align;
1234
1235	/**
1236	* Audio cutoff bandwidth (0 means "automatic")
1237	* - encoding: Set by user.
1238	* - decoding: unused
1239	*/
1240	int cutoff;
1241
1242	/**
1243	* Audio channel layout.
1244	* - encoding: set by user.
1245	* - decoding: set by user, may be overwritten by libavcodec.
1246	*/
1247	uint64_t channel_layout;
1248
1249	/**
1250	* Request decoder to use this channel layout if it can (0 for default)
1251	* - encoding: unused
1252	* - decoding: Set by user.
1253	*/
1254	uint64_t request_channel_layout;
1255
1256	/**
1257	* Type of service that the audio stream conveys.
1258	* - encoding: Set by user.
1259	* - decoding: Set by libavcodec.
1260	*/
1261	enum AVAudioServiceType audio_service_type;
1262
1263	/**
1264	* desired sample format
1265	* - encoding: Not used.
1266	* - decoding: Set by user.
1267	* Decoder will decode to this format if it can.
1268	*/
1269	enum AVSampleFormat request_sample_fmt;
1270
1271	/**
1272	* This callback is called at the beginning of each frame to get data
1273	* buffer(s) for it. There may be one contiguous buffer for all the data or
1274	* there may be a buffer per each data plane or anything in between. What
1275	* this means is, you may set however many entries in buf[] you feel necessary.
1276	* Each buffer must be reference-counted using the AVBuffer API (see description
1277	* of buf[] below).
1278	*
1279	* The following fields will be set in the frame before this callback is
1280	* called:
1281	* - format
1282	* - width, height (video only)
1283	* - sample_rate, channel_layout, nb_samples (audio only)
1284	* Their values may differ from the corresponding values in
1285	* AVCodecContext. This callback must use the frame values, not the codec
1286	* context values, to calculate the required buffer size.
1287	*
1288	* This callback must fill the following fields in the frame:
1289	* - data[]
1290	* - linesize[]
1291	* - extended_data:
1292	* * if the data is planar audio with more than 8 channels, then this
1293	* callback must allocate and fill extended_data to contain all pointers
1294	* to all data planes. data[] must hold as many pointers as it can.
1295	* extended_data must be allocated with av_malloc() and will be freed in
1296	* av_frame_unref().
1297	* * otherwise extended_data must point to data
1298	* - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1299	* the frame's data and extended_data pointers must be contained in these. That
1300	* is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1301	* AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1302	* and av_buffer_ref().
1303	* - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1304	* this callback and filled with the extra buffers if there are more
1305	* buffers than buf[] can hold. extended_buf will be freed in
1306	* av_frame_unref().
1307	*
1308	* If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1309	* avcodec_default_get_buffer2() instead of providing buffers allocated by
1310	* some other means.
1311	*
1312	* Each data plane must be aligned to the maximum required by the target
1313	* CPU.
1314	*
1315	* @see avcodec_default_get_buffer2()
1316	*
1317	* Video:
1318	*
1319	* If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1320	* (read and/or written to if it is writable) later by libavcodec.
1321	*
1322	* avcodec_align_dimensions2() should be used to find the required width and
1323	* height, as they normally need to be rounded up to the next multiple of 16.
1324	*
1325	* Some decoders do not support linesizes changing between frames.
1326	*
1327	* If frame multithreading is used, this callback may be called from a
1328	* different thread, but not from more than one at once. Does not need to be
1329	* reentrant.
1330	*
1331	* @see avcodec_align_dimensions2()
1332	*
1333	* Audio:
1334	*
1335	* Decoders request a buffer of a particular size by setting
1336	* AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1337	* however, utilize only part of the buffer by setting AVFrame.nb_samples
1338	* to a smaller value in the output frame.
1339	*
1340	* As a convenience, av_samples_get_buffer_size() and
1341	* av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1342	* functions to find the required data size and to fill data pointers and
1343	* linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1344	* since all planes must be the same size.
1345	*
1346	* @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1347	*
1348	* - encoding: unused
1349	* - decoding: Set by libavcodec, user can override.
1350	*/
1351	int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
1352
1353	#if FF_API_OLD_ENCDEC
1354	/**
1355	* If non-zero, the decoded audio and video frames returned from
1356	* avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
1357	* and are valid indefinitely. The caller must free them with
1358	* av_frame_unref() when they are not needed anymore.
1359	* Otherwise, the decoded frames must not be freed by the caller and are
1360	* only valid until the next decode call.
1361	*
1362	* This is always automatically enabled if avcodec_receive_frame() is used.
1363	*
1364	* - encoding: unused
1365	* - decoding: set by the caller before avcodec_open2().
1366	*/
1367	attribute_deprecated
1368	int refcounted_frames;
1369	#endif
1370
1371	/* - encoding parameters */
1372	float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1373	float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1374
1375	/**
1376	* minimum quantizer
1377	* - encoding: Set by user.
1378	* - decoding: unused
1379	*/
1380	int qmin;
1381
1382	/**
1383	* maximum quantizer
1384	* - encoding: Set by user.
1385	* - decoding: unused
1386	*/
1387	int qmax;
1388
1389	/**
1390	* maximum quantizer difference between frames
1391	* - encoding: Set by user.
1392	* - decoding: unused
1393	*/
1394	int max_qdiff;
1395
1396	/**
1397	* decoder bitstream buffer size
1398	* - encoding: Set by user.
1399	* - decoding: unused
1400	*/
1401	int rc_buffer_size;
1402
1403	/**
1404	* ratecontrol override, see RcOverride
1405	* - encoding: Allocated/set/freed by user.
1406	* - decoding: unused
1407	*/
1408	int rc_override_count;
1409	RcOverride *rc_override;
1410
1411	/**
1412	* maximum bitrate
1413	* - encoding: Set by user.
1414	* - decoding: Set by user, may be overwritten by libavcodec.
1415	*/
1416	int64_t rc_max_rate;
1417
1418	/**
1419	* minimum bitrate
1420	* - encoding: Set by user.
1421	* - decoding: unused
1422	*/
1423	int64_t rc_min_rate;
1424
1425	/**
1426	* Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1427	* - encoding: Set by user.
1428	* - decoding: unused.
1429	*/
1430	float rc_max_available_vbv_use;
1431
1432	/**
1433	* Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1434	* - encoding: Set by user.
1435	* - decoding: unused.
1436	*/
1437	float rc_min_vbv_overflow_use;
1438
1439	/**
1440	* Number of bits which should be loaded into the rc buffer before decoding starts.
1441	* - encoding: Set by user.
1442	* - decoding: unused
1443	*/
1444	int rc_initial_buffer_occupancy;
1445
1446	#if FF_API_CODER_TYPE
1447	#define FF_CODER_TYPE_VLC 0
1448	#define FF_CODER_TYPE_AC 1
1449	#define FF_CODER_TYPE_RAW 2
1450	#define FF_CODER_TYPE_RLE 3
1451	/**
1452	* @deprecated use encoder private options instead
1453	*/
1454	attribute_deprecated
1455	int coder_type;
1456	#endif /* FF_API_CODER_TYPE */
1457
1458	#if FF_API_PRIVATE_OPT
1459	/** @deprecated use encoder private options instead */
1460	attribute_deprecated
1461	int context_model;
1462	#endif
1463
1464	#if FF_API_PRIVATE_OPT
1465	/** @deprecated use encoder private options instead */
1466	attribute_deprecated
1467	int frame_skip_threshold;
1468
1469	/** @deprecated use encoder private options instead */
1470	attribute_deprecated
1471	int frame_skip_factor;
1472
1473	/** @deprecated use encoder private options instead */
1474	attribute_deprecated
1475	int frame_skip_exp;
1476
1477	/** @deprecated use encoder private options instead */
1478	attribute_deprecated
1479	int frame_skip_cmp;
1480	#endif /* FF_API_PRIVATE_OPT */
1481
1482	/**
1483	* trellis RD quantization
1484	* - encoding: Set by user.
1485	* - decoding: unused
1486	*/
1487	int trellis;
1488
1489	#if FF_API_PRIVATE_OPT
1490	/** @deprecated use encoder private options instead */
1491	attribute_deprecated
1492	int min_prediction_order;
1493
1494	/** @deprecated use encoder private options instead */
1495	attribute_deprecated
1496	int max_prediction_order;
1497
1498	/** @deprecated use encoder private options instead */
1499	attribute_deprecated
1500	int64_t timecode_frame_start;
1501	#endif
1502
1503	#if FF_API_RTP_CALLBACK
1504	/**
1505	* @deprecated unused
1506	*/
1507	/* The RTP callback: This function is called */
1508	/* every time the encoder has a packet to send. */
1509	/* It depends on the encoder if the data starts */
1510	/* with a Start Code (it should). H.263 does. */
1511	/* mb_nb contains the number of macroblocks */
1512	/* encoded in the RTP payload. */
1513	attribute_deprecated
1514	void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
1515	#endif
1516
1517	#if FF_API_PRIVATE_OPT
1518	/** @deprecated use encoder private options instead */
1519	attribute_deprecated
1520	int rtp_payload_size; /* The size of the RTP payload: the coder will */
1521	/* do its best to deliver a chunk with size */
1522	/* below rtp_payload_size, the chunk will start */
1523	/* with a start code on some codecs like H.263. */
1524	/* This doesn't take account of any particular */
1525	/* headers inside the transmitted RTP payload. */
1526	#endif
1527
1528	#if FF_API_STAT_BITS
1529	/* statistics, used for 2-pass encoding */
1530	attribute_deprecated
1531	int mv_bits;
1532	attribute_deprecated
1533	int header_bits;
1534	attribute_deprecated
1535	int i_tex_bits;
1536	attribute_deprecated
1537	int p_tex_bits;
1538	attribute_deprecated
1539	int i_count;
1540	attribute_deprecated
1541	int p_count;
1542	attribute_deprecated
1543	int skip_count;
1544	attribute_deprecated
1545	int misc_bits;
1546
1547	/** @deprecated this field is unused */
1548	attribute_deprecated
1549	int frame_bits;
1550	#endif
1551
1552	/**
1553	* pass1 encoding statistics output buffer
1554	* - encoding: Set by libavcodec.
1555	* - decoding: unused
1556	*/
1557	char *stats_out;
1558
1559	/**
1560	* pass2 encoding statistics input buffer
1561	* Concatenated stuff from stats_out of pass1 should be placed here.
1562	* - encoding: Allocated/set/freed by user.
1563	* - decoding: unused
1564	*/
1565	char *stats_in;
1566
1567	/**
1568	* Work around bugs in encoders which sometimes cannot be detected automatically.
1569	* - encoding: Set by user
1570	* - decoding: Set by user
1571	*/
1572	int workaround_bugs;
1573	#define FF_BUG_AUTODETECT 1 ///< autodetection
1574	#define FF_BUG_XVID_ILACE 4
1575	#define FF_BUG_UMP4 8
1576	#define FF_BUG_NO_PADDING 16
1577	#define FF_BUG_AMV 32
1578	#define FF_BUG_QPEL_CHROMA 64
1579	#define FF_BUG_STD_QPEL 128
1580	#define FF_BUG_QPEL_CHROMA2 256
1581	#define FF_BUG_DIRECT_BLOCKSIZE 512
1582	#define FF_BUG_EDGE 1024
1583	#define FF_BUG_HPEL_CHROMA 2048
1584	#define FF_BUG_DC_CLIP 4096
1585	#define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1586	#define FF_BUG_TRUNCATED 16384
1587	#define FF_BUG_IEDGE 32768
1588
1589	/**
1590	* strictly follow the standard (MPEG-4, ...).
1591	* - encoding: Set by user.
1592	* - decoding: Set by user.
1593	* Setting this to STRICT or higher means the encoder and decoder will
1594	* generally do stupid things, whereas setting it to unofficial or lower
1595	* will mean the encoder might produce output that is not supported by all
1596	* spec-compliant decoders. Decoders don't differentiate between normal,
1597	* unofficial and experimental (that is, they always try to decode things
1598	* when they can) unless they are explicitly asked to behave stupidly
1599	* (=strictly conform to the specs)
1600	*/
1601	int strict_std_compliance;
1602	#define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
1603	#define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
1604	#define FF_COMPLIANCE_NORMAL 0
1605	#define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
1606	#define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
1607
1608	/**
1609	* error concealment flags
1610	* - encoding: unused
1611	* - decoding: Set by user.
1612	*/
1613	int error_concealment;
1614	#define FF_EC_GUESS_MVS 1
1615	#define FF_EC_DEBLOCK 2
1616	#define FF_EC_FAVOR_INTER 256
1617
1618	/**
1619	* debug
1620	* - encoding: Set by user.
1621	* - decoding: Set by user.
1622	*/
1623	int debug;
1624	#define FF_DEBUG_PICT_INFO 1
1625	#define FF_DEBUG_RC 2
1626	#define FF_DEBUG_BITSTREAM 4
1627	#define FF_DEBUG_MB_TYPE 8
1628	#define FF_DEBUG_QP 16
1629	#define FF_DEBUG_DCT_COEFF 0x00000040
1630	#define FF_DEBUG_SKIP 0x00000080
1631	#define FF_DEBUG_STARTCODE 0x00000100
1632	#define FF_DEBUG_ER 0x00000400
1633	#define FF_DEBUG_MMCO 0x00000800
1634	#define FF_DEBUG_BUGS 0x00001000
1635	#define FF_DEBUG_BUFFERS 0x00008000
1636	#define FF_DEBUG_THREADS 0x00010000
1637	#define FF_DEBUG_GREEN_MD 0x00800000
1638	#define FF_DEBUG_NOMC 0x01000000
1639
1640	/**
1641	* Error recognition; may misdetect some more or less valid parts as errors.
1642	* - encoding: Set by user.
1643	* - decoding: Set by user.
1644	*/
1645	int err_recognition;
1646
1647	/**
1648	* Verify checksums embedded in the bitstream (could be of either encoded or
1649	* decoded data, depending on the codec) and print an error message on mismatch.
1650	* If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
1651	* decoder returning an error.
1652	*/
1653	#define AV_EF_CRCCHECK (1<<0)
1654	#define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
1655	#define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
1656	#define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
1657
1658	#define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
1659	#define AV_EF_CAREFUL (1<<16) ///< consider things that violate the spec, are fast to calculate and have not been seen in the wild as errors
1660	#define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
1661	#define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
1662
1663
1664	/**
1665	* opaque 64-bit number (generally a PTS) that will be reordered and
1666	* output in AVFrame.reordered_opaque
1667	* - encoding: Set by libavcodec to the reordered_opaque of the input
1668	* frame corresponding to the last returned packet. Only
1669	* supported by encoders with the
1670	* AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1671	* - decoding: Set by user.
1672	*/
1673	int64_t reordered_opaque;
1674
1675	/**
1676	* Hardware accelerator in use
1677	* - encoding: unused.
1678	* - decoding: Set by libavcodec
1679	*/
1680	const struct AVHWAccel *hwaccel;
1681
1682	/**
1683	* Hardware accelerator context.
1684	* For some hardware accelerators, a global context needs to be
1685	* provided by the user. In that case, this holds display-dependent
1686	* data FFmpeg cannot instantiate itself. Please refer to the
1687	* FFmpeg HW accelerator documentation to know how to fill this
1688	* is. e.g. for VA API, this is a struct vaapi_context.
1689	* - encoding: unused
1690	* - decoding: Set by user
1691	*/
1692	void *hwaccel_context;
1693
1694	/**
1695	* error
1696	* - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1697	* - decoding: unused
1698	*/
1699	uint64_t error[AV_NUM_DATA_POINTERS];
1700
1701	/**
1702	* DCT algorithm, see FF_DCT_* below
1703	* - encoding: Set by user.
1704	* - decoding: unused
1705	*/
1706	int dct_algo;
1707	#define FF_DCT_AUTO 0
1708	#define FF_DCT_FASTINT 1
1709	#define FF_DCT_INT 2
1710	#define FF_DCT_MMX 3
1711	#define FF_DCT_ALTIVEC 5
1712	#define FF_DCT_FAAN 6
1713
1714	/**
1715	* IDCT algorithm, see FF_IDCT_* below.
1716	* - encoding: Set by user.
1717	* - decoding: Set by user.
1718	*/
1719	int idct_algo;
1720	#define FF_IDCT_AUTO 0
1721	#define FF_IDCT_INT 1
1722	#define FF_IDCT_SIMPLE 2
1723	#define FF_IDCT_SIMPLEMMX 3
1724	#define FF_IDCT_ARM 7
1725	#define FF_IDCT_ALTIVEC 8
1726	#define FF_IDCT_SIMPLEARM 10
1727	#define FF_IDCT_XVID 14
1728	#define FF_IDCT_SIMPLEARMV5TE 16
1729	#define FF_IDCT_SIMPLEARMV6 17
1730	#define FF_IDCT_FAAN 20
1731	#define FF_IDCT_SIMPLENEON 22
1732	#define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
1733	#define FF_IDCT_SIMPLEAUTO 128
1734
1735	/**
1736	* bits per sample/pixel from the demuxer (needed for huffyuv).
1737	* - encoding: Set by libavcodec.
1738	* - decoding: Set by user.
1739	*/
1740	int bits_per_coded_sample;
1741
1742	/**
1743	* Bits per sample/pixel of internal libavcodec pixel/sample format.
1744	* - encoding: set by user.
1745	* - decoding: set by libavcodec.
1746	*/
1747	int bits_per_raw_sample;
1748
1749	/**
1750	* low resolution decoding, 1-> 1/2 size, 2->1/4 size
1751	* - encoding: unused
1752	* - decoding: Set by user.
1753	*/
1754	int lowres;
1755
1756	#if FF_API_CODED_FRAME
1757	/**
1758	* the picture in the bitstream
1759	* - encoding: Set by libavcodec.
1760	* - decoding: unused
1761	*
1762	* @deprecated use the quality factor packet side data instead
1763	*/
1764	attribute_deprecated AVFrame *coded_frame;
1765	#endif
1766
1767	/**
1768	* thread count
1769	* is used to decide how many independent tasks should be passed to execute()
1770	* - encoding: Set by user.
1771	* - decoding: Set by user.
1772	*/
1773	int thread_count;
1774
1775	/**
1776	* Which multithreading methods to use.
1777	* Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1778	* so clients which cannot provide future frames should not use it.
1779	*
1780	* - encoding: Set by user, otherwise the default is used.
1781	* - decoding: Set by user, otherwise the default is used.
1782	*/
1783	int thread_type;
1784	#define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1785	#define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1786
1787	/**
1788	* Which multithreading methods are in use by the codec.
1789	* - encoding: Set by libavcodec.
1790	* - decoding: Set by libavcodec.
1791	*/
1792	int active_thread_type;
1793
1794	#if FF_API_THREAD_SAFE_CALLBACKS
1795	/**
1796	* Set by the client if its custom get_buffer() callback can be called
1797	* synchronously from another thread, which allows faster multithreaded decoding.
1798	* draw_horiz_band() will be called from other threads regardless of this setting.
1799	* Ignored if the default get_buffer() is used.
1800	* - encoding: Set by user.
1801	* - decoding: Set by user.
1802	*
1803	* @deprecated the custom get_buffer2() callback should always be
1804	* thread-safe. Thread-unsafe get_buffer2() implementations will be
1805	* invalid starting with LIBAVCODEC_VERSION_MAJOR=60; in other words,
1806	* libavcodec will behave as if this field was always set to 1.
1807	* Callers that want to be forward compatible with future libavcodec
1808	* versions should wrap access to this field in
1809	* #if LIBAVCODEC_VERSION_MAJOR < 60
1810	*/
1811	attribute_deprecated
1812	int thread_safe_callbacks;
1813	#endif
1814
1815	/**
1816	* The codec may call this to execute several independent things.
1817	* It will return only after finishing all tasks.
1818	* The user may replace this with some multithreaded implementation,
1819	* the default implementation will execute the parts serially.
1820	* @param count the number of things to execute
1821	* - encoding: Set by libavcodec, user can override.
1822	* - decoding: Set by libavcodec, user can override.
1823	*/
1824	int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1825
1826	/**
1827	* The codec may call this to execute several independent things.
1828	* It will return only after finishing all tasks.
1829	* The user may replace this with some multithreaded implementation,
1830	* the default implementation will execute the parts serially.
1831	* Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
1832	* @param c context passed also to func
1833	* @param count the number of things to execute
1834	* @param arg2 argument passed unchanged to func
1835	* @param ret return values of executed functions, must have space for "count" values. May be NULL.
1836	* @param func function that will be called count times, with jobnr from 0 to count-1.
1837	* threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1838	* two instances of func executing at the same time will have the same threadnr.
1839	* @return always 0 currently, but code should handle a future improvement where when any call to func
1840	* returns < 0 no further calls to func may be done and < 0 is returned.
1841	* - encoding: Set by libavcodec, user can override.
1842	* - decoding: Set by libavcodec, user can override.
1843	*/
1844	int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1845
1846	/**
1847	* noise vs. sse weight for the nsse comparison function
1848	* - encoding: Set by user.
1849	* - decoding: unused
1850	*/
1851	int nsse_weight;
1852
1853	/**
1854	* profile
1855	* - encoding: Set by user.
1856	* - decoding: Set by libavcodec.
1857	*/
1858	int profile;
1859	#define FF_PROFILE_UNKNOWN -99
1860	#define FF_PROFILE_RESERVED -100
1861
1862	#define FF_PROFILE_AAC_MAIN 0
1863	#define FF_PROFILE_AAC_LOW 1
1864	#define FF_PROFILE_AAC_SSR 2
1865	#define FF_PROFILE_AAC_LTP 3
1866	#define FF_PROFILE_AAC_HE 4
1867	#define FF_PROFILE_AAC_HE_V2 28
1868	#define FF_PROFILE_AAC_LD 22
1869	#define FF_PROFILE_AAC_ELD 38
1870	#define FF_PROFILE_MPEG2_AAC_LOW 128
1871	#define FF_PROFILE_MPEG2_AAC_HE 131
1872
1873	#define FF_PROFILE_DNXHD 0
1874	#define FF_PROFILE_DNXHR_LB 1
1875	#define FF_PROFILE_DNXHR_SQ 2
1876	#define FF_PROFILE_DNXHR_HQ 3
1877	#define FF_PROFILE_DNXHR_HQX 4
1878	#define FF_PROFILE_DNXHR_444 5
1879
1880	#define FF_PROFILE_DTS 20
1881	#define FF_PROFILE_DTS_ES 30
1882	#define FF_PROFILE_DTS_96_24 40
1883	#define FF_PROFILE_DTS_HD_HRA 50
1884	#define FF_PROFILE_DTS_HD_MA 60
1885	#define FF_PROFILE_DTS_EXPRESS 70
1886
1887	#define FF_PROFILE_MPEG2_422 0
1888	#define FF_PROFILE_MPEG2_HIGH 1
1889	#define FF_PROFILE_MPEG2_SS 2
1890	#define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1891	#define FF_PROFILE_MPEG2_MAIN 4
1892	#define FF_PROFILE_MPEG2_SIMPLE 5
1893
1894	#define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1895	#define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1896
1897	#define FF_PROFILE_H264_BASELINE 66
1898	#define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1899	#define FF_PROFILE_H264_MAIN 77
1900	#define FF_PROFILE_H264_EXTENDED 88
1901	#define FF_PROFILE_H264_HIGH 100
1902	#define FF_PROFILE_H264_HIGH_10 110
1903	#define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1904	#define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1905	#define FF_PROFILE_H264_HIGH_422 122
1906	#define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1907	#define FF_PROFILE_H264_STEREO_HIGH 128
1908	#define FF_PROFILE_H264_HIGH_444 144
1909	#define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1910	#define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1911	#define FF_PROFILE_H264_CAVLC_444 44
1912
1913	#define FF_PROFILE_VC1_SIMPLE 0
1914	#define FF_PROFILE_VC1_MAIN 1
1915	#define FF_PROFILE_VC1_COMPLEX 2
1916	#define FF_PROFILE_VC1_ADVANCED 3
1917
1918	#define FF_PROFILE_MPEG4_SIMPLE 0
1919	#define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1920	#define FF_PROFILE_MPEG4_CORE 2
1921	#define FF_PROFILE_MPEG4_MAIN 3
1922	#define FF_PROFILE_MPEG4_N_BIT 4
1923	#define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1924	#define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1925	#define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1926	#define FF_PROFILE_MPEG4_HYBRID 8
1927	#define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1928	#define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1929	#define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1930	#define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1931	#define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1932	#define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1933	#define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1934
1935	#define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1936	#define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1937	#define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1938	#define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1939	#define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1940
1941	#define FF_PROFILE_VP9_0 0
1942	#define FF_PROFILE_VP9_1 1
1943	#define FF_PROFILE_VP9_2 2
1944	#define FF_PROFILE_VP9_3 3
1945
1946	#define FF_PROFILE_HEVC_MAIN 1
1947	#define FF_PROFILE_HEVC_MAIN_10 2
1948	#define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1949	#define FF_PROFILE_HEVC_REXT 4
1950
1951	#define FF_PROFILE_VVC_MAIN_10 1
1952	#define FF_PROFILE_VVC_MAIN_10_444 33
1953
1954	#define FF_PROFILE_AV1_MAIN 0
1955	#define FF_PROFILE_AV1_HIGH 1
1956	#define FF_PROFILE_AV1_PROFESSIONAL 2
1957
1958	#define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1959	#define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1960	#define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1961	#define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1962	#define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1963
1964	#define FF_PROFILE_SBC_MSBC 1
1965
1966	#define FF_PROFILE_PRORES_PROXY 0
1967	#define FF_PROFILE_PRORES_LT 1
1968	#define FF_PROFILE_PRORES_STANDARD 2
1969	#define FF_PROFILE_PRORES_HQ 3
1970	#define FF_PROFILE_PRORES_4444 4
1971	#define FF_PROFILE_PRORES_XQ 5
1972
1973	#define FF_PROFILE_ARIB_PROFILE_A 0
1974	#define FF_PROFILE_ARIB_PROFILE_C 1
1975
1976	#define FF_PROFILE_KLVA_SYNC 0
1977	#define FF_PROFILE_KLVA_ASYNC 1
1978
1979	/**
1980	* level
1981	* - encoding: Set by user.
1982	* - decoding: Set by libavcodec.
1983	*/
1984	int level;
1985	#define FF_LEVEL_UNKNOWN -99
1986
1987	/**
1988	* Skip loop filtering for selected frames.
1989	* - encoding: unused
1990	* - decoding: Set by user.
1991	*/
1992	enum AVDiscard skip_loop_filter;
1993
1994	/**
1995	* Skip IDCT/dequantization for selected frames.
1996	* - encoding: unused
1997	* - decoding: Set by user.
1998	*/
1999	enum AVDiscard skip_idct;
2000
2001	/**
2002	* Skip decoding for selected frames.
2003	* - encoding: unused
2004	* - decoding: Set by user.
2005	*/
2006	enum AVDiscard skip_frame;
2007
2008	/**
2009	* Header containing style information for text subtitles.
2010	* For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2011	* [Script Info] and [V4+ Styles] section, plus the [Events] line and
2012	* the Format line following. It shouldn't include any Dialogue line.
2013	* - encoding: Set/allocated/freed by user (before avcodec_open2())
2014	* - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2015	*/
2016	uint8_t *subtitle_header;
2017	int subtitle_header_size;
2018
2019	#if FF_API_VBV_DELAY
2020	/**
2021	* VBV delay coded in the last frame (in periods of a 27 MHz clock).
2022	* Used for compliant TS muxing.
2023	* - encoding: Set by libavcodec.
2024	* - decoding: unused.
2025	* @deprecated this value is now exported as a part of
2026	* AV_PKT_DATA_CPB_PROPERTIES packet side data
2027	*/
2028	attribute_deprecated
2029	uint64_t vbv_delay;
2030	#endif
2031
2032	#if FF_API_SIDEDATA_ONLY_PKT
2033	/**
2034	* Encoding only and set by default. Allow encoders to output packets
2035	* that do not contain any encoded data, only side data.
2036	*
2037	* Some encoders need to output such packets, e.g. to update some stream
2038	* parameters at the end of encoding.
2039	*
2040	* @deprecated this field disables the default behaviour and
2041	* it is kept only for compatibility.
2042	*/
2043	attribute_deprecated
2044	int side_data_only_packets;
2045	#endif
2046
2047	/**
2048	* Audio only. The number of "priming" samples (padding) inserted by the
2049	* encoder at the beginning of the audio. I.e. this number of leading
2050	* decoded samples must be discarded by the caller to get the original audio
2051	* without leading padding.
2052	*
2053	* - decoding: unused
2054	* - encoding: Set by libavcodec. The timestamps on the output packets are
2055	* adjusted by the encoder so that they always refer to the
2056	* first sample of the data actually contained in the packet,
2057	* including any added padding. E.g. if the timebase is
2058	* 1/samplerate and the timestamp of the first input sample is
2059	* 0, the timestamp of the first output packet will be
2060	* -initial_padding.
2061	*/
2062	int initial_padding;
2063
2064	/**
2065	* - decoding: For codecs that store a framerate value in the compressed
2066	* bitstream, the decoder may export it here. { 0, 1} when
2067	* unknown.
2068	* - encoding: May be used to signal the framerate of CFR content to an
2069	* encoder.
2070	*/
2071	AVRational framerate;
2072
2073	/**
2074	* Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
2075	* - encoding: unused.
2076	* - decoding: Set by libavcodec before calling get_format()
2077	*/
2078	enum AVPixelFormat sw_pix_fmt;
2079
2080	/**
2081	* Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
2082	* - encoding unused.
2083	* - decoding set by user.
2084	*/
2085	AVRational pkt_timebase;
2086
2087	/**
2088	* AVCodecDescriptor
2089	* - encoding: unused.
2090	* - decoding: set by libavcodec.
2091	*/
2092	const AVCodecDescriptor *codec_descriptor;
2093
2094	/**
2095	* Current statistics for PTS correction.
2096	* - decoding: maintained and used by libavcodec, not intended to be used by user apps
2097	* - encoding: unused
2098	*/
2099	int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
2100	int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
2101	int64_t pts_correction_last_pts; /// PTS of the last frame
2102	int64_t pts_correction_last_dts; /// DTS of the last frame
2103
2104	/**
2105	* Character encoding of the input subtitles file.
2106	* - decoding: set by user
2107	* - encoding: unused
2108	*/
2109	char *sub_charenc;
2110
2111	/**
2112	* Subtitles character encoding mode. Formats or codecs might be adjusting
2113	* this setting (if they are doing the conversion themselves for instance).
2114	* - decoding: set by libavcodec
2115	* - encoding: unused
2116	*/
2117	int sub_charenc_mode;
2118	#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)
2119	#define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
2120	#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
2121	#define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
2122
2123	/**
2124	* Skip processing alpha if supported by codec.
2125	* Note that if the format uses pre-multiplied alpha (common with VP6,
2126	* and recommended due to better video quality/compression)
2127	* the image will look as if alpha-blended onto a black background.
2128	* However for formats that do not use pre-multiplied alpha
2129	* there might be serious artefacts (though e.g. libswscale currently
2130	* assumes pre-multiplied alpha anyway).
2131	*
2132	* - decoding: set by user
2133	* - encoding: unused
2134	*/
2135	int skip_alpha;
2136
2137	/**
2138	* Number of samples to skip after a discontinuity
2139	* - decoding: unused
2140	* - encoding: set by libavcodec
2141	*/
2142	int seek_preroll;
2143
2144	#if FF_API_DEBUG_MV
2145	/**
2146	* @deprecated unused
2147	*/
2148	attribute_deprecated
2149	int debug_mv;
2150	#define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
2151	#define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
2152	#define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2153	#endif
2154
2155	/**
2156	* custom intra quantization matrix
2157	* - encoding: Set by user, can be NULL.
2158	* - decoding: unused.
2159	*/
2160	uint16_t *chroma_intra_matrix;
2161
2162	/**
2163	* dump format separator.
2164	* can be ", " or "\n " or anything else
2165	* - encoding: Set by user.
2166	* - decoding: Set by user.
2167	*/
2168	uint8_t *dump_separator;
2169
2170	/**
2171	* ',' separated list of allowed decoders.
2172	* If NULL then all are allowed
2173	* - encoding: unused
2174	* - decoding: set by user
2175	*/
2176	char *codec_whitelist;
2177
2178	/**
2179	* Properties of the stream that gets decoded
2180	* - encoding: unused
2181	* - decoding: set by libavcodec
2182	*/
2183	unsigned properties;
2184	#define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
2185	#define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
2186
2187	/**
2188	* Additional data associated with the entire coded stream.
2189	*
2190	* - decoding: unused
2191	* - encoding: may be set by libavcodec after avcodec_open2().
2192	*/
2193	AVPacketSideData *coded_side_data;
2194	int nb_coded_side_data;
2195
2196	/**
2197	* A reference to the AVHWFramesContext describing the input (for encoding)
2198	* or output (decoding) frames. The reference is set by the caller and
2199	* afterwards owned (and freed) by libavcodec - it should never be read by
2200	* the caller after being set.
2201	*
2202	* - decoding: This field should be set by the caller from the get_format()
2203	* callback. The previous reference (if any) will always be
2204	* unreffed by libavcodec before the get_format() call.
2205	*
2206	* If the default get_buffer2() is used with a hwaccel pixel
2207	* format, then this AVHWFramesContext will be used for
2208	* allocating the frame buffers.
2209	*
2210	* - encoding: For hardware encoders configured to use a hwaccel pixel
2211	* format, this field should be set by the caller to a reference
2212	* to the AVHWFramesContext describing input frames.
2213	* AVHWFramesContext.format must be equal to
2214	* AVCodecContext.pix_fmt.
2215	*
2216	* This field should be set before avcodec_open2() is called.
2217	*/
2218	AVBufferRef *hw_frames_ctx;
2219
2220	/**
2221	* Control the form of AVSubtitle.rects[N]->ass
2222	* - decoding: set by user
2223	* - encoding: unused
2224	*/
2225	int sub_text_format;
2226	#define FF_SUB_TEXT_FMT_ASS 0
2227	#if FF_API_ASS_TIMING
2228	#define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
2229	#endif
2230
2231	/**
2232	* Audio only. The amount of padding (in samples) appended by the encoder to
2233	* the end of the audio. I.e. this number of decoded samples must be
2234	* discarded by the caller from the end of the stream to get the original
2235	* audio without any trailing padding.
2236	*
2237	* - decoding: unused
2238	* - encoding: unused
2239	*/
2240	int trailing_padding;
2241
2242	/**
2243	* The number of pixels per image to maximally accept.
2244	*
2245	* - decoding: set by user
2246	* - encoding: set by user
2247	*/
2248	int64_t max_pixels;
2249
2250	/**
2251	* A reference to the AVHWDeviceContext describing the device which will
2252	* be used by a hardware encoder/decoder. The reference is set by the
2253	* caller and afterwards owned (and freed) by libavcodec.
2254	*
2255	* This should be used if either the codec device does not require
2256	* hardware frames or any that are used are to be allocated internally by
2257	* libavcodec. If the user wishes to supply any of the frames used as
2258	* encoder input or decoder output then hw_frames_ctx should be used
2259	* instead. When hw_frames_ctx is set in get_format() for a decoder, this
2260	* field will be ignored while decoding the associated stream segment, but
2261	* may again be used on a following one after another get_format() call.
2262	*
2263	* For both encoders and decoders this field should be set before
2264	* avcodec_open2() is called and must not be written to thereafter.
2265	*
2266	* Note that some decoders may require this field to be set initially in
2267	* order to support hw_frames_ctx at all - in that case, all frames
2268	* contexts used must be created on the same device.
2269	*/
2270	AVBufferRef *hw_device_ctx;
2271
2272	/**
2273	* Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
2274	* decoding (if active).
2275	* - encoding: unused
2276	* - decoding: Set by user (either before avcodec_open2(), or in the
2277	* AVCodecContext.get_format callback)
2278	*/
2279	int hwaccel_flags;
2280
2281	/**
2282	* Video decoding only. Certain video codecs support cropping, meaning that
2283	* only a sub-rectangle of the decoded frame is intended for display. This
2284	* option controls how cropping is handled by libavcodec.
2285	*
2286	* When set to 1 (the default), libavcodec will apply cropping internally.
2287	* I.e. it will modify the output frame width/height fields and offset the
2288	* data pointers (only by as much as possible while preserving alignment, or
2289	* by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
2290	* the frames output by the decoder refer only to the cropped area. The
2291	* crop_* fields of the output frames will be zero.
2292	*
2293	* When set to 0, the width/height fields of the output frames will be set
2294	* to the coded dimensions and the crop_* fields will describe the cropping
2295	* rectangle. Applying the cropping is left to the caller.
2296	*
2297	* @warning When hardware acceleration with opaque output frames is used,
2298	* libavcodec is unable to apply cropping from the top/left border.
2299	*
2300	* @note when this option is set to zero, the width/height fields of the
2301	* AVCodecContext and output AVFrames have different meanings. The codec
2302	* context fields store display dimensions (with the coded dimensions in
2303	* coded_width/height), while the frame fields store the coded dimensions
2304	* (with the display dimensions being determined by the crop_* fields).
2305	*/
2306	int apply_cropping;
2307
2308	/*
2309	* Video decoding only. Sets the number of extra hardware frames which
2310	* the decoder will allocate for use by the caller. This must be set
2311	* before avcodec_open2() is called.
2312	*
2313	* Some hardware decoders require all frames that they will use for
2314	* output to be defined in advance before decoding starts. For such
2315	* decoders, the hardware frame pool must therefore be of a fixed size.
2316	* The extra frames set here are on top of any number that the decoder
2317	* needs internally in order to operate normally (for example, frames
2318	* used as reference pictures).
2319	*/
2320	int extra_hw_frames;
2321
2322	/**
2323	* The percentage of damaged samples to discard a frame.
2324	*
2325	* - decoding: set by user
2326	* - encoding: unused
2327	*/
2328	int discard_damaged_percentage;
2329
2330	/**
2331	* The number of samples per frame to maximally accept.
2332	*
2333	* - decoding: set by user
2334	* - encoding: set by user
2335	*/
2336	int64_t max_samples;
2337
2338	/**
2339	* Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
2340	* metadata exported in frame, packet, or coded stream side data by
2341	* decoders and encoders.
2342	*
2343	* - decoding: set by user
2344	* - encoding: set by user
2345	*/
2346	int export_side_data;
2347
2348	/**
2349	* This callback is called at the beginning of each packet to get a data
2350	* buffer for it.
2351	*
2352	* The following field will be set in the packet before this callback is
2353	* called:
2354	* - size
2355	* This callback must use the above value to calculate the required buffer size,
2356	* which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
2357	*
2358	* This callback must fill the following fields in the packet:
2359	* - data: alignment requirements for AVPacket apply, if any. Some architectures and
2360	* encoders may benefit from having aligned data.
2361	* - buf: must contain a pointer to an AVBufferRef structure. The packet's
2362	* data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
2363	* and av_buffer_ref().
2364	*
2365	* If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2366	* avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2367	* some other means.
2368	*
2369	* The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2370	* They may be used for example to hint what use the buffer may get after being
2371	* created.
2372	* Implementations of this callback may ignore flags they don't understand.
2373	* If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2374	* (read and/or written to if it is writable) later by libavcodec.
2375	*
2376	* This callback must be thread-safe, as when frame threading is used, it may
2377	* be called from multiple threads simultaneously.
2378	*
2379	* @see avcodec_default_get_encode_buffer()
2380	*
2381	* - encoding: Set by libavcodec, user can override.
2382	* - decoding: unused
2383	*/
2384	int (*get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags);
2385	} AVCodecContext;
2386
2387	#if FF_API_CODEC_GET_SET
2388	/**
2389	* Accessors for some AVCodecContext fields. These used to be provided for ABI
2390	* compatibility, and do not need to be used anymore.
2391	*/
2392	attribute_deprecated
2393	AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
2394	attribute_deprecated
2395	void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
2396
2397	attribute_deprecated
2398	const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
2399	attribute_deprecated
2400	void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
2401
2402	attribute_deprecated
2403	unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
2404
2405	attribute_deprecated
2406	int av_codec_get_lowres(const AVCodecContext *avctx);
2407	attribute_deprecated
2408	void av_codec_set_lowres(AVCodecContext *avctx, int val);
2409
2410	attribute_deprecated
2411	int av_codec_get_seek_preroll(const AVCodecContext *avctx);
2412	attribute_deprecated
2413	void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
2414
2415	attribute_deprecated
2416	uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
2417	attribute_deprecated
2418	void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
2419	#endif
2420
2421	struct AVSubtitle;
2422
2423	#if FF_API_CODEC_GET_SET
2424	attribute_deprecated
2425	int av_codec_get_max_lowres(const AVCodec *codec);
2426	#endif
2427
2428	struct MpegEncContext;
2429
2430	/**
2431	* @defgroup lavc_hwaccel AVHWAccel
2432	*
2433	* @note Nothing in this structure should be accessed by the user. At some
2434	* point in future it will not be externally visible at all.
2435	*
2436	* @{
2437	*/
2438	typedef struct AVHWAccel {
2439	/**
2440	* Name of the hardware accelerated codec.
2441	* The name is globally unique among encoders and among decoders (but an
2442	* encoder and a decoder can share the same name).
2443	*/
2444	const char *name;
2445
2446	/**
2447	* Type of codec implemented by the hardware accelerator.
2448	*
2449	* See AVMEDIA_TYPE_xxx
2450	*/
2451	enum AVMediaType type;
2452
2453	/**
2454	* Codec implemented by the hardware accelerator.
2455	*
2456	* See AV_CODEC_ID_xxx
2457	*/
2458	enum AVCodecID id;
2459
2460	/**
2461	* Supported pixel format.
2462	*
2463	* Only hardware accelerated formats are supported here.
2464	*/
2465	enum AVPixelFormat pix_fmt;
2466
2467	/**
2468	* Hardware accelerated codec capabilities.
2469	* see AV_HWACCEL_CODEC_CAP_*
2470	*/
2471	int capabilities;
2472
2473	/*****************************************************************
2474	* No fields below this line are part of the public API. They
2475	* may not be used outside of libavcodec and can be changed and
2476	* removed at will.
2477	* New public fields should be added right above.
2478	*****************************************************************
2479	*/
2480
2481	/**
2482	* Allocate a custom buffer
2483	*/
2484	int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
2485
2486	/**
2487	* Called at the beginning of each frame or field picture.
2488	*
2489	* Meaningful frame information (codec specific) is guaranteed to
2490	* be parsed at this point. This function is mandatory.
2491	*
2492	* Note that buf can be NULL along with buf_size set to 0.
2493	* Otherwise, this means the whole frame is available at this point.
2494	*
2495	* @param avctx the codec context
2496	* @param buf the frame data buffer base
2497	* @param buf_size the size of the frame in bytes
2498	* @return zero if successful, a negative value otherwise
2499	*/
2500	int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2501
2502	/**
2503	* Callback for parameter data (SPS/PPS/VPS etc).
2504	*
2505	* Useful for hardware decoders which keep persistent state about the
2506	* video parameters, and need to receive any changes to update that state.
2507	*
2508	* @param avctx the codec context
2509	* @param type the nal unit type
2510	* @param buf the nal unit data buffer
2511	* @param buf_size the size of the nal unit in bytes
2512	* @return zero if successful, a negative value otherwise
2513	*/
2514	int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
2515
2516	/**
2517	* Callback for each slice.
2518	*
2519	* Meaningful slice information (codec specific) is guaranteed to
2520	* be parsed at this point. This function is mandatory.
2521	* The only exception is XvMC, that works on MB level.
2522	*
2523	* @param avctx the codec context
2524	* @param buf the slice data buffer base
2525	* @param buf_size the size of the slice in bytes
2526	* @return zero if successful, a negative value otherwise
2527	*/
2528	int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2529
2530	/**
2531	* Called at the end of each frame or field picture.
2532	*
2533	* The whole picture is parsed at this point and can now be sent
2534	* to the hardware accelerator. This function is mandatory.
2535	*
2536	* @param avctx the codec context
2537	* @return zero if successful, a negative value otherwise
2538	*/
2539	int (*end_frame)(AVCodecContext *avctx);
2540
2541	/**
2542	* Size of per-frame hardware accelerator private data.
2543	*
2544	* Private data is allocated with av_mallocz() before
2545	* AVCodecContext.get_buffer() and deallocated after
2546	* AVCodecContext.release_buffer().
2547	*/
2548	int frame_priv_data_size;
2549
2550	/**
2551	* Called for every Macroblock in a slice.
2552	*
2553	* XvMC uses it to replace the ff_mpv_reconstruct_mb().
2554	* Instead of decoding to raw picture, MB parameters are
2555	* stored in an array provided by the video driver.
2556	*
2557	* @param s the mpeg context
2558	*/
2559	void (*decode_mb)(struct MpegEncContext *s);
2560
2561	/**
2562	* Initialize the hwaccel private data.
2563	*
2564	* This will be called from ff_get_format(), after hwaccel and
2565	* hwaccel_context are set and the hwaccel private data in AVCodecInternal
2566	* is allocated.
2567	*/
2568	int (*init)(AVCodecContext *avctx);
2569
2570	/**
2571	* Uninitialize the hwaccel private data.
2572	*
2573	* This will be called from get_format() or avcodec_close(), after hwaccel
2574	* and hwaccel_context are already uninitialized.
2575	*/
2576	int (*uninit)(AVCodecContext *avctx);
2577
2578	/**
2579	* Size of the private data to allocate in
2580	* AVCodecInternal.hwaccel_priv_data.
2581	*/
2582	int priv_data_size;
2583
2584	/**
2585	* Internal hwaccel capabilities.
2586	*/
2587	int caps_internal;
2588
2589	/**
2590	* Fill the given hw_frames context with current codec parameters. Called
2591	* from get_format. Refer to avcodec_get_hw_frames_parameters() for
2592	* details.
2593	*
2594	* This CAN be called before AVHWAccel.init is called, and you must assume
2595	* that avctx->hwaccel_priv_data is invalid.
2596	*/
2597	int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
2598	} AVHWAccel;
2599
2600	/**
2601	* HWAccel is experimental and is thus avoided in favor of non experimental
2602	* codecs
2603	*/
2604	#define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2605
2606	/**
2607	* Hardware acceleration should be used for decoding even if the codec level
2608	* used is unknown or higher than the maximum supported level reported by the
2609	* hardware driver.
2610	*
2611	* It's generally a good idea to pass this flag unless you have a specific
2612	* reason not to, as hardware tends to under-report supported levels.
2613	*/
2614	#define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2615
2616	/**
2617	* Hardware acceleration can output YUV pixel formats with a different chroma
2618	* sampling than 4:2:0 and/or other than 8 bits per component.
2619	*/
2620	#define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2621
2622	/**
2623	* Hardware acceleration should still be attempted for decoding when the
2624	* codec profile does not match the reported capabilities of the hardware.
2625	*
2626	* For example, this can be used to try to decode baseline profile H.264
2627	* streams in hardware - it will often succeed, because many streams marked
2628	* as baseline profile actually conform to constrained baseline profile.
2629	*
2630	* @warning If the stream is actually not supported then the behaviour is
2631	* undefined, and may include returning entirely incorrect output
2632	* while indicating success.
2633	*/
2634	#define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2635
2636	/**
2637	* @}
2638	*/
2639
2640	#if FF_API_AVPICTURE
2641	/**
2642	* @defgroup lavc_picture AVPicture
2643	*
2644	* Functions for working with AVPicture
2645	* @{
2646	*/
2647
2648	/**
2649	* Picture data structure.
2650	*
2651	* Up to four components can be stored into it, the last component is
2652	* alpha.
2653	* @deprecated use AVFrame or imgutils functions instead
2654	*/
2655	typedef struct AVPicture {
2656	attribute_deprecated
2657	uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
2658	attribute_deprecated
2659	int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
2660	} AVPicture;
2661
2662	/**
2663	* @}
2664	*/
2665	#endif
2666
2667	enum AVSubtitleType {
2668	SUBTITLE_NONE,
2669
2670	SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2671
2672	/**
2673	* Plain text, the text field must be set by the decoder and is
2674	* authoritative. ass and pict fields may contain approximations.
2675	*/
2676	SUBTITLE_TEXT,
2677
2678	/**
2679	* Formatted text, the ass field must be set by the decoder and is
2680	* authoritative. pict and text fields may contain approximations.
2681	*/
2682	SUBTITLE_ASS,
2683	};
2684
2685	#define AV_SUBTITLE_FLAG_FORCED 0x00000001
2686
2687	typedef struct AVSubtitleRect {
2688	int x; ///< top left corner of pict, undefined when pict is not set
2689	int y; ///< top left corner of pict, undefined when pict is not set
2690	int w; ///< width of pict, undefined when pict is not set
2691	int h; ///< height of pict, undefined when pict is not set
2692	int nb_colors; ///< number of colors in pict, undefined when pict is not set
2693
2694	#if FF_API_AVPICTURE
2695	/**
2696	* @deprecated unused
2697	*/
2698	attribute_deprecated
2699	AVPicture pict;
2700	#endif
2701	/**
2702	* data+linesize for the bitmap of this subtitle.
2703	* Can be set for text/ass as well once they are rendered.
2704	*/
2705	uint8_t *data[4];
2706	int linesize[4];
2707
2708	enum AVSubtitleType type;
2709
2710	char *text; ///< 0 terminated plain UTF-8 text
2711
2712	/**
2713	* 0 terminated ASS/SSA compatible event line.
2714	* The presentation of this is unaffected by the other values in this
2715	* struct.
2716	*/
2717	char *ass;
2718
2719	int flags;
2720	} AVSubtitleRect;
2721
2722	typedef struct AVSubtitle {
2723	uint16_t format; /* 0 = graphics */
2724	uint32_t start_display_time; /* relative to packet pts, in ms */
2725	uint32_t end_display_time; /* relative to packet pts, in ms */
2726	unsigned num_rects;
2727	AVSubtitleRect **rects;
2728	int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2729	} AVSubtitle;
2730
2731	#if FF_API_NEXT
2732	/**
2733	* If c is NULL, returns the first registered codec,
2734	* if c is non-NULL, returns the next registered codec after c,
2735	* or NULL if c is the last one.
2736	*/
2737	attribute_deprecated
2738	AVCodec *av_codec_next(const AVCodec *c);
2739	#endif
2740
2741	/**
2742	* Return the LIBAVCODEC_VERSION_INT constant.
2743	*/
2744	unsigned avcodec_version(void);
2745
2746	/**
2747	* Return the libavcodec build-time configuration.
2748	*/
2749	const char *avcodec_configuration(void);
2750
2751	/**
2752	* Return the libavcodec license.
2753	*/
2754	const char *avcodec_license(void);
2755
2756	#if FF_API_NEXT
2757	/**
2758	* @deprecated Calling this function is unnecessary.
2759	*/
2760	attribute_deprecated
2761	void avcodec_register(AVCodec *codec);
2762
2763	/**
2764	* @deprecated Calling this function is unnecessary.
2765	*/
2766	attribute_deprecated
2767	void avcodec_register_all(void);
2768	#endif
2769
2770	/**
2771	* Allocate an AVCodecContext and set its fields to default values. The
2772	* resulting struct should be freed with avcodec_free_context().
2773	*
2774	* @param codec if non-NULL, allocate private data and initialize defaults
2775	* for the given codec. It is illegal to then call avcodec_open2()
2776	* with a different codec.
2777	* If NULL, then the codec-specific defaults won't be initialized,
2778	* which may result in suboptimal default settings (this is
2779	* important mainly for encoders, e.g. libx264).
2780	*
2781	* @return An AVCodecContext filled with default values or NULL on failure.
2782	*/
2783	AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
2784
2785	/**
2786	* Free the codec context and everything associated with it and write NULL to
2787	* the provided pointer.
2788	*/
2789	void avcodec_free_context(AVCodecContext **avctx);
2790
2791	#if FF_API_GET_CONTEXT_DEFAULTS
2792	/**
2793	* @deprecated This function should not be used, as closing and opening a codec
2794	* context multiple time is not supported. A new codec context should be
2795	* allocated for each new use.
2796	*/
2797	int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
2798	#endif
2799
2800	/**
2801	* Get the AVClass for AVCodecContext. It can be used in combination with
2802	* AV_OPT_SEARCH_FAKE_OBJ for examining options.
2803	*
2804	* @see av_opt_find().
2805	*/
2806	const AVClass *avcodec_get_class(void);
2807
2808	#if FF_API_GET_FRAME_CLASS
2809	/**
2810	* @deprecated This function should not be used.
2811	*/
2812	attribute_deprecated
2813	const AVClass *avcodec_get_frame_class(void);
2814	#endif
2815
2816	/**
2817	* Get the AVClass for AVSubtitleRect. It can be used in combination with
2818	* AV_OPT_SEARCH_FAKE_OBJ for examining options.
2819	*
2820	* @see av_opt_find().
2821	*/
2822	const AVClass *avcodec_get_subtitle_rect_class(void);
2823
2824	#if FF_API_COPY_CONTEXT
2825	/**
2826	* Copy the settings of the source AVCodecContext into the destination
2827	* AVCodecContext. The resulting destination codec context will be
2828	* unopened, i.e. you are required to call avcodec_open2() before you
2829	* can use this AVCodecContext to decode/encode video/audio data.
2830	*
2831	* @param dest target codec context, should be initialized with
2832	* avcodec_alloc_context3(NULL), but otherwise uninitialized
2833	* @param src source codec context
2834	* @return AVERROR() on error (e.g. memory allocation error), 0 on success
2835	*
2836	* @deprecated The semantics of this function are ill-defined and it should not
2837	* be used. If you need to transfer the stream parameters from one codec context
2838	* to another, use an intermediate AVCodecParameters instance and the
2839	* avcodec_parameters_from_context() / avcodec_parameters_to_context()
2840	* functions.
2841	*/
2842	attribute_deprecated
2843	int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
2844	#endif
2845
2846	/**
2847	* Fill the parameters struct based on the values from the supplied codec
2848	* context. Any allocated fields in par are freed and replaced with duplicates
2849	* of the corresponding fields in codec.
2850	*
2851	* @return >= 0 on success, a negative AVERROR code on failure
2852	*/
2853	int avcodec_parameters_from_context(AVCodecParameters *par,
2854	const AVCodecContext *codec);
2855
2856	/**
2857	* Fill the codec context based on the values from the supplied codec
2858	* parameters. Any allocated fields in codec that have a corresponding field in
2859	* par are freed and replaced with duplicates of the corresponding field in par.
2860	* Fields in codec that do not have a counterpart in par are not touched.
2861	*
2862	* @return >= 0 on success, a negative AVERROR code on failure.
2863	*/
2864	int avcodec_parameters_to_context(AVCodecContext *codec,
2865	const AVCodecParameters *par);
2866
2867	/**
2868	* Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2869	* function the context has to be allocated with avcodec_alloc_context3().
2870	*
2871	* The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2872	* avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2873	* retrieving a codec.
2874	*
2875	* @warning This function is not thread safe!
2876	*
2877	* @note Always call this function before using decoding routines (such as
2878	* @ref avcodec_receive_frame()).
2879	*
2880	* @code
2881	* av_dict_set(&opts, "b", "2.5M", 0);
2882	* codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2883	* if (!codec)
2884	* exit(1);
2885	*
2886	* context = avcodec_alloc_context3(codec);
2887	*
2888	* if (avcodec_open2(context, codec, opts) < 0)
2889	* exit(1);
2890	* @endcode
2891	*
2892	* @param avctx The context to initialize.
2893	* @param codec The codec to open this context for. If a non-NULL codec has been
2894	* previously passed to avcodec_alloc_context3() or
2895	* for this context, then this parameter MUST be either NULL or
2896	* equal to the previously passed codec.
2897	* @param options A dictionary filled with AVCodecContext and codec-private options.
2898	* On return this object will be filled with options that were not found.
2899	*
2900	* @return zero on success, a negative value on error
2901	* @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2902	* av_dict_set(), av_opt_find().
2903	*/
2904	int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2905
2906	/**
2907	* Close a given AVCodecContext and free all the data associated with it
2908	* (but not the AVCodecContext itself).
2909	*
2910	* Calling this function on an AVCodecContext that hasn't been opened will free
2911	* the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2912	* codec. Subsequent calls will do nothing.
2913	*
2914	* @note Do not use this function. Use avcodec_free_context() to destroy a
2915	* codec context (either open or closed). Opening and closing a codec context
2916	* multiple times is not supported anymore -- use multiple codec contexts
2917	* instead.
2918	*/
2919	int avcodec_close(AVCodecContext *avctx);
2920
2921	/**
2922	* Free all allocated data in the given subtitle struct.
2923	*
2924	* @param sub AVSubtitle to free.
2925	*/
2926	void avsubtitle_free(AVSubtitle *sub);
2927
2928	/**
2929	* @}
2930	*/
2931
2932	/**
2933	* @addtogroup lavc_decoding
2934	* @{
2935	*/
2936
2937	/**
2938	* The default callback for AVCodecContext.get_buffer2(). It is made public so
2939	* it can be called by custom get_buffer2() implementations for decoders without
2940	* AV_CODEC_CAP_DR1 set.
2941	*/
2942	int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
2943
2944	/**
2945	* The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2946	* it can be called by custom get_encode_buffer() implementations for encoders without
2947	* AV_CODEC_CAP_DR1 set.
2948	*/
2949	int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags);
2950
2951	/**
2952	* Modify width and height values so that they will result in a memory
2953	* buffer that is acceptable for the codec if you do not use any horizontal
2954	* padding.
2955	*
2956	* May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2957	*/
2958	void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
2959
2960	/**
2961	* Modify width and height values so that they will result in a memory
2962	* buffer that is acceptable for the codec if you also ensure that all
2963	* line sizes are a multiple of the respective linesize_align[i].
2964	*
2965	* May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2966	*/
2967	void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
2968	int linesize_align[AV_NUM_DATA_POINTERS]);
2969
2970	/**
2971	* Converts AVChromaLocation to swscale x/y chroma position.
2972	*
2973	* The positions represent the chroma (0,0) position in a coordinates system
2974	* with luma (0,0) representing the origin and luma(1,1) representing 256,256
2975	*
2976	* @param xpos horizontal chroma sample position
2977	* @param ypos vertical chroma sample position
2978	*/
2979	int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
2980
2981	/**
2982	* Converts swscale x/y chroma position to AVChromaLocation.
2983	*
2984	* The positions represent the chroma (0,0) position in a coordinates system
2985	* with luma (0,0) representing the origin and luma(1,1) representing 256,256
2986	*
2987	* @param xpos horizontal chroma sample position
2988	* @param ypos vertical chroma sample position
2989	*/
2990	enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
2991
2992	#if FF_API_OLD_ENCDEC
2993	/**
2994	* Decode the audio frame of size avpkt->size from avpkt->data into frame.
2995	*
2996	* Some decoders may support multiple frames in a single AVPacket. Such
2997	* decoders would then just decode the first frame and the return value would be
2998	* less than the packet size. In this case, avcodec_decode_audio4 has to be
2999	* called again with an AVPacket containing the remaining data in order to
3000	* decode the second frame, etc... Even if no frames are returned, the packet
3001	* needs to be fed to the decoder with remaining data until it is completely
3002	* consumed or an error occurs.
3003	*
3004	* Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
3005	* and output. This means that for some packets they will not immediately
3006	* produce decoded output and need to be flushed at the end of decoding to get
3007	* all the decoded data. Flushing is done by calling this function with packets
3008	* with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3009	* returning samples. It is safe to flush even those decoders that are not
3010	* marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
3011	*
3012	* @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
3013	* larger than the actual read bytes because some optimized bitstream
3014	* readers read 32 or 64 bits at once and could read over the end.
3015	*
3016	* @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3017	* before packets may be fed to the decoder.
3018	*
3019	* @param avctx the codec context
3020	* @param[out] frame The AVFrame in which to store decoded audio samples.
3021	* The decoder will allocate a buffer for the decoded frame by
3022	* calling the AVCodecContext.get_buffer2() callback.
3023	* When AVCodecContext.refcounted_frames is set to 1, the frame is
3024	* reference counted and the returned reference belongs to the
3025	* caller. The caller must release the frame using av_frame_unref()
3026	* when the frame is no longer needed. The caller may safely write
3027	* to the frame if av_frame_is_writable() returns 1.
3028	* When AVCodecContext.refcounted_frames is set to 0, the returned
3029	* reference belongs to the decoder and is valid only until the
3030	* next call to this function or until closing or flushing the
3031	* decoder. The caller may not write to it.
3032	* @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
3033	* non-zero. Note that this field being set to zero
3034	* does not mean that an error has occurred. For
3035	* decoders with AV_CODEC_CAP_DELAY set, no given decode
3036	* call is guaranteed to produce a frame.
3037	* @param[in] avpkt The input AVPacket containing the input buffer.
3038	* At least avpkt->data and avpkt->size should be set. Some
3039	* decoders might also require additional fields to be set.
3040	* @return A negative error code is returned if an error occurred during
3041	* decoding, otherwise the number of bytes consumed from the input
3042	* AVPacket is returned.
3043	*
3044	* @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
3045	*/
3046	attribute_deprecated
3047	int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
3048	int *got_frame_ptr, const AVPacket *avpkt);
3049
3050	/**
3051	* Decode the video frame of size avpkt->size from avpkt->data into picture.
3052	* Some decoders may support multiple frames in a single AVPacket, such
3053	* decoders would then just decode the first frame.
3054	*
3055	* @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
3056	* the actual read bytes because some optimized bitstream readers read 32 or 64
3057	* bits at once and could read over the end.
3058	*
3059	* @warning The end of the input buffer buf should be set to 0 to ensure that
3060	* no overreading happens for damaged MPEG streams.
3061	*
3062	* @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
3063	* between input and output, these need to be fed with avpkt->data=NULL,
3064	* avpkt->size=0 at the end to return the remaining frames.
3065	*
3066	* @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3067	* before packets may be fed to the decoder.
3068	*
3069	* @param avctx the codec context
3070	* @param[out] picture The AVFrame in which the decoded video frame will be stored.
3071	* Use av_frame_alloc() to get an AVFrame. The codec will
3072	* allocate memory for the actual bitmap by calling the
3073	* AVCodecContext.get_buffer2() callback.
3074	* When AVCodecContext.refcounted_frames is set to 1, the frame is
3075	* reference counted and the returned reference belongs to the
3076	* caller. The caller must release the frame using av_frame_unref()
3077	* when the frame is no longer needed. The caller may safely write
3078	* to the frame if av_frame_is_writable() returns 1.
3079	* When AVCodecContext.refcounted_frames is set to 0, the returned
3080	* reference belongs to the decoder and is valid only until the
3081	* next call to this function or until closing or flushing the
3082	* decoder. The caller may not write to it.
3083	*
3084	* @param[in] avpkt The input AVPacket containing the input buffer.
3085	* You can create such packet with av_init_packet() and by then setting
3086	* data and size, some decoders might in addition need other fields like
3087	* flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
3088	* fields possible.
3089	* @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
3090	* @return On error a negative value is returned, otherwise the number of bytes
3091	* used or zero if no frame could be decompressed.
3092	*
3093	* @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
3094	*/
3095	attribute_deprecated
3096	int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
3097	int *got_picture_ptr,
3098	const AVPacket *avpkt);
3099	#endif
3100
3101	/**
3102	* Decode a subtitle message.
3103	* Return a negative value on error, otherwise return the number of bytes used.
3104	* If no subtitle could be decompressed, got_sub_ptr is zero.
3105	* Otherwise, the subtitle is stored in *sub.
3106	* Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
3107	* simplicity, because the performance difference is expected to be negligible
3108	* and reusing a get_buffer written for video codecs would probably perform badly
3109	* due to a potentially very different allocation pattern.
3110	*
3111	* Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
3112	* and output. This means that for some packets they will not immediately
3113	* produce decoded output and need to be flushed at the end of decoding to get
3114	* all the decoded data. Flushing is done by calling this function with packets
3115	* with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3116	* returning subtitles. It is safe to flush even those decoders that are not
3117	* marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
3118	*
3119	* @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3120	* before packets may be fed to the decoder.
3121	*
3122	* @param avctx the codec context
3123	* @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
3124	* must be freed with avsubtitle_free if *got_sub_ptr is set.
3125	* @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
3126	* @param[in] avpkt The input AVPacket containing the input buffer.
3127	*/
3128	int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
3129	int *got_sub_ptr,
3130	AVPacket *avpkt);
3131
3132	/**
3133	* Supply raw packet data as input to a decoder.
3134	*
3135	* Internally, this call will copy relevant AVCodecContext fields, which can
3136	* influence decoding per-packet, and apply them when the packet is actually
3137	* decoded. (For example AVCodecContext.skip_frame, which might direct the
3138	* decoder to drop the frame contained by the packet sent with this function.)
3139	*
3140	* @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
3141	* larger than the actual read bytes because some optimized bitstream
3142	* readers read 32 or 64 bits at once and could read over the end.
3143	*
3144	* @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
3145	* on the same AVCodecContext. It will return unexpected results now
3146	* or in future libavcodec versions.
3147	*
3148	* @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3149	* before packets may be fed to the decoder.
3150	*
3151	* @param avctx codec context
3152	* @param[in] avpkt The input AVPacket. Usually, this will be a single video
3153	* frame, or several complete audio frames.
3154	* Ownership of the packet remains with the caller, and the
3155	* decoder will not write to the packet. The decoder may create
3156	* a reference to the packet data (or copy it if the packet is
3157	* not reference-counted).
3158	* Unlike with older APIs, the packet is always fully consumed,
3159	* and if it contains multiple frames (e.g. some audio codecs),
3160	* will require you to call avcodec_receive_frame() multiple
3161	* times afterwards before you can send a new packet.
3162	* It can be NULL (or an AVPacket with data set to NULL and
3163	* size set to 0); in this case, it is considered a flush
3164	* packet, which signals the end of the stream. Sending the
3165	* first flush packet will return success. Subsequent ones are
3166	* unnecessary and will return AVERROR_EOF. If the decoder
3167	* still has frames buffered, it will return them after sending
3168	* a flush packet.
3169	*
3170	* @return 0 on success, otherwise negative error code:
3171	* AVERROR(EAGAIN): input is not accepted in the current state - user
3172	* must read output with avcodec_receive_frame() (once
3173	* all output is read, the packet should be resent, and
3174	* the call will not fail with EAGAIN).
3175	* AVERROR_EOF: the decoder has been flushed, and no new packets can
3176	* be sent to it (also returned if more than 1 flush
3177	* packet is sent)
3178	* AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
3179	* AVERROR(ENOMEM): failed to add packet to internal queue, or similar
3180	* other errors: legitimate decoding errors
3181	*/
3182	int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
3183
3184	/**
3185	* Return decoded output data from a decoder.
3186	*
3187	* @param avctx codec context
3188	* @param frame This will be set to a reference-counted video or audio
3189	* frame (depending on the decoder type) allocated by the
3190	* decoder. Note that the function will always call
3191	* av_frame_unref(frame) before doing anything else.
3192	*
3193	* @return
3194	* 0: success, a frame was returned
3195	* AVERROR(EAGAIN): output is not available in this state - user must try
3196	* to send new input
3197	* AVERROR_EOF: the decoder has been fully flushed, and there will be
3198	* no more output frames
3199	* AVERROR(EINVAL): codec not opened, or it is an encoder
3200	* AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
3201	* with respect to first decoded frame. Applicable
3202	* when flag AV_CODEC_FLAG_DROPCHANGED is set.
3203	* other negative values: legitimate decoding errors
3204	*/
3205	int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
3206
3207	/**
3208	* Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
3209	* to retrieve buffered output packets.
3210	*
3211	* @param avctx codec context
3212	* @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
3213	* Ownership of the frame remains with the caller, and the
3214	* encoder will not write to the frame. The encoder may create
3215	* a reference to the frame data (or copy it if the frame is
3216	* not reference-counted).
3217	* It can be NULL, in which case it is considered a flush
3218	* packet. This signals the end of the stream. If the encoder
3219	* still has packets buffered, it will return them after this
3220	* call. Once flushing mode has been entered, additional flush
3221	* packets are ignored, and sending frames will return
3222	* AVERROR_EOF.
3223	*
3224	* For audio:
3225	* If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
3226	* can have any number of samples.
3227	* If it is not set, frame->nb_samples must be equal to
3228	* avctx->frame_size for all frames except the last.
3229	* The final frame may be smaller than avctx->frame_size.
3230	* @return 0 on success, otherwise negative error code:
3231	* AVERROR(EAGAIN): input is not accepted in the current state - user
3232	* must read output with avcodec_receive_packet() (once
3233	* all output is read, the packet should be resent, and
3234	* the call will not fail with EAGAIN).
3235	* AVERROR_EOF: the encoder has been flushed, and no new frames can
3236	* be sent to it
3237	* AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
3238	* decoder, or requires flush
3239	* AVERROR(ENOMEM): failed to add packet to internal queue, or similar
3240	* other errors: legitimate encoding errors
3241	*/
3242	int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
3243
3244	/**
3245	* Read encoded data from the encoder.
3246	*
3247	* @param avctx codec context
3248	* @param avpkt This will be set to a reference-counted packet allocated by the
3249	* encoder. Note that the function will always call
3250	* av_packet_unref(avpkt) before doing anything else.
3251	* @return 0 on success, otherwise negative error code:
3252	* AVERROR(EAGAIN): output is not available in the current state - user
3253	* must try to send input
3254	* AVERROR_EOF: the encoder has been fully flushed, and there will be
3255	* no more output packets
3256	* AVERROR(EINVAL): codec not opened, or it is a decoder
3257	* other errors: legitimate encoding errors
3258	*/
3259	int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
3260
3261	/**
3262	* Create and return a AVHWFramesContext with values adequate for hardware
3263	* decoding. This is meant to get called from the get_format callback, and is
3264	* a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
3265	* This API is for decoding with certain hardware acceleration modes/APIs only.
3266	*
3267	* The returned AVHWFramesContext is not initialized. The caller must do this
3268	* with av_hwframe_ctx_init().
3269	*
3270	* Calling this function is not a requirement, but makes it simpler to avoid
3271	* codec or hardware API specific details when manually allocating frames.
3272	*
3273	* Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
3274	* which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
3275	* it unnecessary to call this function or having to care about
3276	* AVHWFramesContext initialization at all.
3277	*
3278	* There are a number of requirements for calling this function:
3279	*
3280	* - It must be called from get_format with the same avctx parameter that was
3281	* passed to get_format. Calling it outside of get_format is not allowed, and
3282	* can trigger undefined behavior.
3283	* - The function is not always supported (see description of return values).
3284	* Even if this function returns successfully, hwaccel initialization could
3285	* fail later. (The degree to which implementations check whether the stream
3286	* is actually supported varies. Some do this check only after the user's
3287	* get_format callback returns.)
3288	* - The hw_pix_fmt must be one of the choices suggested by get_format. If the
3289	* user decides to use a AVHWFramesContext prepared with this API function,
3290	* the user must return the same hw_pix_fmt from get_format.
3291	* - The device_ref passed to this function must support the given hw_pix_fmt.
3292	* - After calling this API function, it is the user's responsibility to
3293	* initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
3294	* and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
3295	* before returning from get_format (this is implied by the normal
3296	* AVCodecContext.hw_frames_ctx API rules).
3297	* - The AVHWFramesContext parameters may change every time time get_format is
3298	* called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
3299	* you are inherently required to go through this process again on every
3300	* get_format call.
3301	* - It is perfectly possible to call this function without actually using
3302	* the resulting AVHWFramesContext. One use-case might be trying to reuse a
3303	* previously initialized AVHWFramesContext, and calling this API function
3304	* only to test whether the required frame parameters have changed.
3305	* - Fields that use dynamically allocated values of any kind must not be set
3306	* by the user unless setting them is explicitly allowed by the documentation.
3307	* If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
3308	* the new free callback must call the potentially set previous free callback.
3309	* This API call may set any dynamically allocated fields, including the free
3310	* callback.
3311	*
3312	* The function will set at least the following fields on AVHWFramesContext
3313	* (potentially more, depending on hwaccel API):
3314	*
3315	* - All fields set by av_hwframe_ctx_alloc().
3316	* - Set the format field to hw_pix_fmt.
3317	* - Set the sw_format field to the most suited and most versatile format. (An
3318	* implication is that this will prefer generic formats over opaque formats
3319	* with arbitrary restrictions, if possible.)
3320	* - Set the width/height fields to the coded frame size, rounded up to the
3321	* API-specific minimum alignment.
3322	* - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
3323	* field to the number of maximum reference surfaces possible with the codec,
3324	* plus 1 surface for the user to work (meaning the user can safely reference
3325	* at most 1 decoded surface at a time), plus additional buffering introduced
3326	* by frame threading. If the hwaccel does not require pre-allocation, the
3327	* field is left to 0, and the decoder will allocate new surfaces on demand
3328	* during decoding.
3329	* - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
3330	* hardware API.
3331	*
3332	* Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
3333	* with basic frame parameters set.
3334	*
3335	* The function is stateless, and does not change the AVCodecContext or the
3336	* device_ref AVHWDeviceContext.
3337	*
3338	* @param avctx The context which is currently calling get_format, and which
3339	* implicitly contains all state needed for filling the returned
3340	* AVHWFramesContext properly.
3341	* @param device_ref A reference to the AVHWDeviceContext describing the device
3342	* which will be used by the hardware decoder.
3343	* @param hw_pix_fmt The hwaccel format you are going to return from get_format.
3344	* @param out_frames_ref On success, set to a reference to an _uninitialized_
3345	* AVHWFramesContext, created from the given device_ref.
3346	* Fields will be set to values required for decoding.
3347	* Not changed if an error is returned.
3348	* @return zero on success, a negative value on error. The following error codes
3349	* have special semantics:
3350	* AVERROR(ENOENT): the decoder does not support this functionality. Setup
3351	* is always manual, or it is a decoder which does not
3352	* support setting AVCodecContext.hw_frames_ctx at all,
3353	* or it is a software format.
3354	* AVERROR(EINVAL): it is known that hardware decoding is not supported for
3355	* this configuration, or the device_ref is not supported
3356	* for the hwaccel referenced by hw_pix_fmt.
3357	*/
3358	int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
3359	AVBufferRef *device_ref,
3360	enum AVPixelFormat hw_pix_fmt,
3361	AVBufferRef **out_frames_ref);
3362
3363
3364
3365	/**
3366	* @defgroup lavc_parsing Frame parsing
3367	* @{
3368	*/
3369
3370	enum AVPictureStructure {
3371	AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
3372	AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
3373	AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
3374	AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
3375	};
3376
3377	typedef struct AVCodecParserContext {
3378	void *priv_data;
3379	struct AVCodecParser *parser;
3380	int64_t frame_offset; /* offset of the current frame */
3381	int64_t cur_offset; /* current offset
3382	(incremented by each av_parser_parse()) */
3383	int64_t next_frame_offset; /* offset of the next frame */
3384	/* video info */
3385	int pict_type; /* XXX: Put it back in AVCodecContext. */
3386	/**
3387	* This field is used for proper frame duration computation in lavf.
3388	* It signals, how much longer the frame duration of the current frame
3389	* is compared to normal frame duration.
3390	*
3391	* frame_duration = (1 + repeat_pict) * time_base
3392	*
3393	* It is used by codecs like H.264 to display telecined material.
3394	*/
3395	int repeat_pict; /* XXX: Put it back in AVCodecContext. */
3396	int64_t pts; /* pts of the current frame */
3397	int64_t dts; /* dts of the current frame */
3398
3399	/* private data */
3400	int64_t last_pts;
3401	int64_t last_dts;
3402	int fetch_timestamp;
3403
3404	#define AV_PARSER_PTS_NB 4
3405	int cur_frame_start_index;
3406	int64_t cur_frame_offset[AV_PARSER_PTS_NB];
3407	int64_t cur_frame_pts[AV_PARSER_PTS_NB];
3408	int64_t cur_frame_dts[AV_PARSER_PTS_NB];
3409
3410	int flags;
3411	#define PARSER_FLAG_COMPLETE_FRAMES 0x0001
3412	#define PARSER_FLAG_ONCE 0x0002
3413	/// Set if the parser has a valid file offset
3414	#define PARSER_FLAG_FETCHED_OFFSET 0x0004
3415	#define PARSER_FLAG_USE_CODEC_TS 0x1000
3416
3417	int64_t offset; ///< byte offset from starting packet start
3418	int64_t cur_frame_end[AV_PARSER_PTS_NB];
3419
3420	/**
3421	* Set by parser to 1 for key frames and 0 for non-key frames.
3422	* It is initialized to -1, so if the parser doesn't set this flag,
3423	* old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
3424	* will be used.
3425	*/
3426	int key_frame;
3427
3428	#if FF_API_CONVERGENCE_DURATION
3429	/**
3430	* @deprecated unused
3431	*/
3432	attribute_deprecated
3433	int64_t convergence_duration;
3434	#endif
3435
3436	// Timestamp generation support:
3437	/**
3438	* Synchronization point for start of timestamp generation.
3439	*
3440	* Set to >0 for sync point, 0 for no sync point and <0 for undefined
3441	* (default).
3442	*
3443	* For example, this corresponds to presence of H.264 buffering period
3444	* SEI message.
3445	*/
3446	int dts_sync_point;
3447
3448	/**
3449	* Offset of the current timestamp against last timestamp sync point in
3450	* units of AVCodecContext.time_base.
3451	*
3452	* Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3453	* contain a valid timestamp offset.
3454	*
3455	* Note that the timestamp of sync point has usually a nonzero
3456	* dts_ref_dts_delta, which refers to the previous sync point. Offset of
3457	* the next frame after timestamp sync point will be usually 1.
3458	*
3459	* For example, this corresponds to H.264 cpb_removal_delay.
3460	*/
3461	int dts_ref_dts_delta;
3462
3463	/**
3464	* Presentation delay of current frame in units of AVCodecContext.time_base.
3465	*
3466	* Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3467	* contain valid non-negative timestamp delta (presentation time of a frame
3468	* must not lie in the past).
3469	*
3470	* This delay represents the difference between decoding and presentation
3471	* time of the frame.
3472	*
3473	* For example, this corresponds to H.264 dpb_output_delay.
3474	*/
3475	int pts_dts_delta;
3476
3477	/**
3478	* Position of the packet in file.
3479	*
3480	* Analogous to cur_frame_pts/dts
3481	*/
3482	int64_t cur_frame_pos[AV_PARSER_PTS_NB];
3483
3484	/**
3485	* Byte position of currently parsed frame in stream.
3486	*/
3487	int64_t pos;
3488
3489	/**
3490	* Previous frame byte position.
3491	*/
3492	int64_t last_pos;
3493
3494	/**
3495	* Duration of the current frame.
3496	* For audio, this is in units of 1 / AVCodecContext.sample_rate.
3497	* For all other types, this is in units of AVCodecContext.time_base.
3498	*/
3499	int duration;
3500
3501	enum AVFieldOrder field_order;
3502
3503	/**
3504	* Indicate whether a picture is coded as a frame, top field or bottom field.
3505	*
3506	* For example, H.264 field_pic_flag equal to 0 corresponds to
3507	* AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
3508	* equal to 1 and bottom_field_flag equal to 0 corresponds to
3509	* AV_PICTURE_STRUCTURE_TOP_FIELD.
3510	*/
3511	enum AVPictureStructure picture_structure;
3512
3513	/**
3514	* Picture number incremented in presentation or output order.
3515	* This field may be reinitialized at the first picture of a new sequence.
3516	*
3517	* For example, this corresponds to H.264 PicOrderCnt.
3518	*/
3519	int output_picture_number;
3520
3521	/**
3522	* Dimensions of the decoded video intended for presentation.
3523	*/
3524	int width;
3525	int height;
3526
3527	/**
3528	* Dimensions of the coded video.
3529	*/
3530	int coded_width;
3531	int coded_height;
3532
3533	/**
3534	* The format of the coded data, corresponds to enum AVPixelFormat for video
3535	* and for enum AVSampleFormat for audio.
3536	*
3537	* Note that a decoder can have considerable freedom in how exactly it
3538	* decodes the data, so the format reported here might be different from the
3539	* one returned by a decoder.
3540	*/
3541	int format;
3542	} AVCodecParserContext;
3543
3544	typedef struct AVCodecParser {
3545	int codec_ids[5]; /* several codec IDs are permitted */
3546	int priv_data_size;
3547	int (*parser_init)(AVCodecParserContext *s);
3548	/* This callback never returns an error, a negative value means that
3549	* the frame start was in a previous packet. */
3550	int (*parser_parse)(AVCodecParserContext *s,
3551	AVCodecContext *avctx,
3552	const uint8_t **poutbuf, int *poutbuf_size,
3553	const uint8_t *buf, int buf_size);
3554	void (*parser_close)(AVCodecParserContext *s);
3555	int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
3556	#if FF_API_NEXT
3557	attribute_deprecated
3558	struct AVCodecParser *next;
3559	#endif
3560	} AVCodecParser;
3561
3562	/**
3563	* Iterate over all registered codec parsers.
3564	*
3565	* @param opaque a pointer where libavcodec will store the iteration state. Must
3566	* point to NULL to start the iteration.
3567	*
3568	* @return the next registered codec parser or NULL when the iteration is
3569	* finished
3570	*/
3571	const AVCodecParser *av_parser_iterate(void **opaque);
3572
3573	#if FF_API_NEXT
3574	attribute_deprecated
3575	AVCodecParser *av_parser_next(const AVCodecParser *c);
3576
3577	attribute_deprecated
3578	void av_register_codec_parser(AVCodecParser *parser);
3579	#endif
3580	AVCodecParserContext *av_parser_init(int codec_id);
3581
3582	/**
3583	* Parse a packet.
3584	*
3585	* @param s parser context.
3586	* @param avctx codec context.
3587	* @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
3588	* @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
3589	* @param buf input buffer.
3590	* @param buf_size buffer size in bytes without the padding. I.e. the full buffer
3591	size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
3592	To signal EOF, this should be 0 (so that the last frame
3593	can be output).
3594	* @param pts input presentation timestamp.
3595	* @param dts input decoding timestamp.
3596	* @param pos input byte position in stream.
3597	* @return the number of bytes of the input bitstream used.
3598	*
3599	* Example:
3600	* @code
3601	* while(in_len){
3602	* len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
3603	* in_data, in_len,
3604	* pts, dts, pos);
3605	* in_data += len;
3606	* in_len -= len;
3607	*
3608	* if(size)
3609	* decode_frame(data, size);
3610	* }
3611	* @endcode
3612	*/
3613	int av_parser_parse2(AVCodecParserContext *s,
3614	AVCodecContext *avctx,
3615	uint8_t **poutbuf, int *poutbuf_size,
3616	const uint8_t *buf, int buf_size,
3617	int64_t pts, int64_t dts,
3618	int64_t pos);
3619
3620	#if FF_API_PARSER_CHANGE
3621	/**
3622	* @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
3623	* @deprecated Use dump_extradata, remove_extra or extract_extradata
3624	* bitstream filters instead.
3625	*/
3626	attribute_deprecated
3627	int av_parser_change(AVCodecParserContext *s,
3628	AVCodecContext *avctx,
3629	uint8_t **poutbuf, int *poutbuf_size,
3630	const uint8_t *buf, int buf_size, int keyframe);
3631	#endif
3632	void av_parser_close(AVCodecParserContext *s);
3633
3634	/**
3635	* @}
3636	* @}
3637	*/
3638
3639	/**
3640	* @addtogroup lavc_encoding
3641	* @{
3642	*/
3643
3644	#if FF_API_OLD_ENCDEC
3645	/**
3646	* Encode a frame of audio.
3647	*
3648	* Takes input samples from frame and writes the next output packet, if
3649	* available, to avpkt. The output packet does not necessarily contain data for
3650	* the most recent frame, as encoders can delay, split, and combine input frames
3651	* internally as needed.
3652	*
3653	* @param avctx codec context
3654	* @param avpkt output AVPacket.
3655	* The user can supply an output buffer by setting
3656	* avpkt->data and avpkt->size prior to calling the
3657	* function, but if the size of the user-provided data is not
3658	* large enough, encoding will fail. If avpkt->data and
3659	* avpkt->size are set, avpkt->destruct must also be set. All
3660	* other AVPacket fields will be reset by the encoder using
3661	* av_init_packet(). If avpkt->data is NULL, the encoder will
3662	* allocate it. The encoder will set avpkt->size to the size
3663	* of the output packet.
3664	*
3665	* If this function fails or produces no output, avpkt will be
3666	* freed using av_packet_unref().
3667	* @param[in] frame AVFrame containing the raw audio data to be encoded.
3668	* May be NULL when flushing an encoder that has the
3669	* AV_CODEC_CAP_DELAY capability set.
3670	* If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
3671	* can have any number of samples.
3672	* If it is not set, frame->nb_samples must be equal to
3673	* avctx->frame_size for all frames except the last.
3674	* The final frame may be smaller than avctx->frame_size.
3675	* @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
3676	* output packet is non-empty, and to 0 if it is
3677	* empty. If the function returns an error, the
3678	* packet can be assumed to be invalid, and the
3679	* value of got_packet_ptr is undefined and should
3680	* not be used.
3681	* @return 0 on success, negative error code on failure
3682	*
3683	* @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead.
3684	* If allowed and required, set AVCodecContext.get_encode_buffer to
3685	* a custom function to pass user supplied output buffers.
3686	*/
3687	attribute_deprecated
3688	int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
3689	const AVFrame *frame, int *got_packet_ptr);
3690
3691	/**
3692	* Encode a frame of video.
3693	*
3694	* Takes input raw video data from frame and writes the next output packet, if
3695	* available, to avpkt. The output packet does not necessarily contain data for
3696	* the most recent frame, as encoders can delay and reorder input frames
3697	* internally as needed.
3698	*
3699	* @param avctx codec context
3700	* @param avpkt output AVPacket.
3701	* The user can supply an output buffer by setting
3702	* avpkt->data and avpkt->size prior to calling the
3703	* function, but if the size of the user-provided data is not
3704	* large enough, encoding will fail. All other AVPacket fields
3705	* will be reset by the encoder using av_init_packet(). If
3706	* avpkt->data is NULL, the encoder will allocate it.
3707	* The encoder will set avpkt->size to the size of the
3708	* output packet. The returned data (if any) belongs to the
3709	* caller, he is responsible for freeing it.
3710	*
3711	* If this function fails or produces no output, avpkt will be
3712	* freed using av_packet_unref().
3713	* @param[in] frame AVFrame containing the raw video data to be encoded.
3714	* May be NULL when flushing an encoder that has the
3715	* AV_CODEC_CAP_DELAY capability set.
3716	* @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
3717	* output packet is non-empty, and to 0 if it is
3718	* empty. If the function returns an error, the
3719	* packet can be assumed to be invalid, and the
3720	* value of got_packet_ptr is undefined and should
3721	* not be used.
3722	* @return 0 on success, negative error code on failure
3723	*
3724	* @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead.
3725	* If allowed and required, set AVCodecContext.get_encode_buffer to
3726	* a custom function to pass user supplied output buffers.
3727	*/
3728	attribute_deprecated
3729	int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
3730	const AVFrame *frame, int *got_packet_ptr);
3731	#endif
3732
3733	int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3734	const AVSubtitle *sub);
3735
3736
3737	/**
3738	* @}
3739	*/
3740
3741	#if FF_API_AVPICTURE
3742	/**
3743	* @addtogroup lavc_picture
3744	* @{
3745	*/
3746
3747	/**
3748	* @deprecated unused
3749	*/
3750	attribute_deprecated
3751	int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
3752
3753	/**
3754	* @deprecated unused
3755	*/
3756	attribute_deprecated
3757	void avpicture_free(AVPicture *picture);
3758
3759	/**
3760	* @deprecated use av_image_fill_arrays() instead.
3761	*/
3762	attribute_deprecated
3763	int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
3764	enum AVPixelFormat pix_fmt, int width, int height);
3765
3766	/**
3767	* @deprecated use av_image_copy_to_buffer() instead.
3768	*/
3769	attribute_deprecated
3770	int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
3771	int width, int height,
3772	unsigned char *dest, int dest_size);
3773
3774	/**
3775	* @deprecated use av_image_get_buffer_size() instead.
3776	*/
3777	attribute_deprecated
3778	int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
3779
3780	/**
3781	* @deprecated av_image_copy() instead.
3782	*/
3783	attribute_deprecated
3784	void av_picture_copy(AVPicture *dst, const AVPicture *src,
3785	enum AVPixelFormat pix_fmt, int width, int height);
3786
3787	/**
3788	* @deprecated unused
3789	*/
3790	attribute_deprecated
3791	int av_picture_crop(AVPicture *dst, const AVPicture *src,
3792	enum AVPixelFormat pix_fmt, int top_band, int left_band);
3793
3794	/**
3795	* @deprecated unused
3796	*/
3797	attribute_deprecated
3798	int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
3799	int padtop, int padbottom, int padleft, int padright, int *color);
3800
3801	/**
3802	* @}
3803	*/
3804	#endif
3805
3806	/**
3807	* @defgroup lavc_misc Utility functions
3808	* @ingroup libavc
3809	*
3810	* Miscellaneous utility functions related to both encoding and decoding
3811	* (or neither).
3812	* @{
3813	*/
3814
3815	/**
3816	* @defgroup lavc_misc_pixfmt Pixel formats
3817	*
3818	* Functions for working with pixel formats.
3819	* @{
3820	*/
3821
3822	#if FF_API_GETCHROMA
3823	/**
3824	* @deprecated Use av_pix_fmt_get_chroma_sub_sample
3825	*/
3826
3827	attribute_deprecated
3828	void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
3829	#endif
3830
3831	/**
3832	* Return a value representing the fourCC code associated to the
3833	* pixel format pix_fmt, or 0 if no associated fourCC code can be
3834	* found.
3835	*/
3836	unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
3837
3838	/**
3839	* Find the best pixel format to convert to given a certain source pixel
3840	* format. When converting from one pixel format to another, information loss
3841	* may occur. For example, when converting from RGB24 to GRAY, the color
3842	* information will be lost. Similarly, other losses occur when converting from
3843	* some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
3844	* the given pixel formats should be used to suffer the least amount of loss.
3845	* The pixel formats from which it chooses one, are determined by the
3846	* pix_fmt_list parameter.
3847	*
3848	*
3849	* @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
3850	* @param[in] src_pix_fmt source pixel format
3851	* @param[in] has_alpha Whether the source pixel format alpha channel is used.
3852	* @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
3853	* @return The best pixel format to convert to or -1 if none was found.
3854	*/
3855	enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
3856	enum AVPixelFormat src_pix_fmt,
3857	int has_alpha, int *loss_ptr);
3858
3859	#if FF_API_AVCODEC_PIX_FMT
3860	/**
3861	* @deprecated see av_get_pix_fmt_loss()
3862	*/
3863	attribute_deprecated
3864	int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
3865	int has_alpha);
3866	/**
3867	* @deprecated see av_find_best_pix_fmt_of_2()
3868	*/
3869	attribute_deprecated
3870	enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
3871	enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
3872
3873	attribute_deprecated
3874	enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
3875	enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
3876	#endif
3877
3878	enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
3879
3880	/**
3881	* @}
3882	*/
3883
3884	#if FF_API_TAG_STRING
3885	/**
3886	* Put a string representing the codec tag codec_tag in buf.
3887	*
3888	* @param buf buffer to place codec tag in
3889	* @param buf_size size in bytes of buf
3890	* @param codec_tag codec tag to assign
3891	* @return the length of the string that would have been generated if
3892	* enough space had been available, excluding the trailing null
3893	*
3894	* @deprecated see av_fourcc_make_string() and av_fourcc2str().
3895	*/
3896	attribute_deprecated
3897	size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
3898	#endif
3899
3900	void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
3901
3902	/**
3903	* Return a name for the specified profile, if available.
3904	*
3905	* @param codec the codec that is searched for the given profile
3906	* @param profile the profile value for which a name is requested
3907	* @return A name for the profile if found, NULL otherwise.
3908	*/
3909	const char *av_get_profile_name(const AVCodec *codec, int profile);
3910
3911	/**
3912	* Return a name for the specified profile, if available.
3913	*
3914	* @param codec_id the ID of the codec to which the requested profile belongs
3915	* @param profile the profile value for which a name is requested
3916	* @return A name for the profile if found, NULL otherwise.
3917	*
3918	* @note unlike av_get_profile_name(), which searches a list of profiles
3919	* supported by a specific decoder or encoder implementation, this
3920	* function searches the list of profiles from the AVCodecDescriptor
3921	*/
3922	const char *avcodec_profile_name(enum AVCodecID codec_id, int profile);
3923
3924	int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
3925	int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
3926	//FIXME func typedef
3927
3928	/**
3929	* Fill AVFrame audio data and linesize pointers.
3930	*
3931	* The buffer buf must be a preallocated buffer with a size big enough
3932	* to contain the specified samples amount. The filled AVFrame data
3933	* pointers will point to this buffer.
3934	*
3935	* AVFrame extended_data channel pointers are allocated if necessary for
3936	* planar audio.
3937	*
3938	* @param frame the AVFrame
3939	* frame->nb_samples must be set prior to calling the
3940	* function. This function fills in frame->data,
3941	* frame->extended_data, frame->linesize[0].
3942	* @param nb_channels channel count
3943	* @param sample_fmt sample format
3944	* @param buf buffer to use for frame data
3945	* @param buf_size size of buffer
3946	* @param align plane size sample alignment (0 = default)
3947	* @return >=0 on success, negative error code on failure
3948	* @todo return the size in bytes required to store the samples in
3949	* case of success, at the next libavutil bump
3950	*/
3951	int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
3952	enum AVSampleFormat sample_fmt, const uint8_t *buf,
3953	int buf_size, int align);
3954
3955	/**
3956	* Reset the internal codec state / flush internal buffers. Should be called
3957	* e.g. when seeking or when switching to a different stream.
3958	*
3959	* @note for decoders, when refcounted frames are not used
3960	* (i.e. avctx->refcounted_frames is 0), this invalidates the frames previously
3961	* returned from the decoder. When refcounted frames are used, the decoder just
3962	* releases any references it might keep internally, but the caller's reference
3963	* remains valid.
3964	*
3965	* @note for encoders, this function will only do something if the encoder
3966	* declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3967	* will drain any remaining packets, and can then be re-used for a different
3968	* stream (as opposed to sending a null frame which will leave the encoder
3969	* in a permanent EOF state after draining). This can be desirable if the
3970	* cost of tearing down and replacing the encoder instance is high.
3971	*/
3972	void avcodec_flush_buffers(AVCodecContext *avctx);
3973
3974	/**
3975	* Return codec bits per sample.
3976	*
3977	* @param[in] codec_id the codec
3978	* @return Number of bits per sample or zero if unknown for the given codec.
3979	*/
3980	int av_get_bits_per_sample(enum AVCodecID codec_id);
3981
3982	/**
3983	* Return the PCM codec associated with a sample format.
3984	* @param be endianness, 0 for little, 1 for big,
3985	* -1 (or anything else) for native
3986	* @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
3987	*/
3988	enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
3989
3990	/**
3991	* Return codec bits per sample.
3992	* Only return non-zero if the bits per sample is exactly correct, not an
3993	* approximation.
3994	*
3995	* @param[in] codec_id the codec
3996	* @return Number of bits per sample or zero if unknown for the given codec.
3997	*/
3998	int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
3999
4000	/**
4001	* Return audio frame duration.
4002	*
4003	* @param avctx codec context
4004	* @param frame_bytes size of the frame, or 0 if unknown
4005	* @return frame duration, in samples, if known. 0 if not able to
4006	* determine.
4007	*/
4008	int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
4009
4010	/**
4011	* This function is the same as av_get_audio_frame_duration(), except it works
4012	* with AVCodecParameters instead of an AVCodecContext.
4013	*/
4014	int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
4015
4016	#if FF_API_OLD_BSF
4017	typedef struct AVBitStreamFilterContext {
4018	void *priv_data;
4019	const struct AVBitStreamFilter *filter;
4020	AVCodecParserContext *parser;
4021	struct AVBitStreamFilterContext *next;
4022	/**
4023	* Internal default arguments, used if NULL is passed to av_bitstream_filter_filter().
4024	* Not for access by library users.
4025	*/
4026	char *args;
4027	} AVBitStreamFilterContext;
4028
4029	/**
4030	* @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4031	* is deprecated. Use the new bitstream filtering API (using AVBSFContext).
4032	*/
4033	attribute_deprecated
4034	void av_register_bitstream_filter(AVBitStreamFilter *bsf);
4035	/**
4036	* @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4037	* is deprecated. Use av_bsf_get_by_name(), av_bsf_alloc(), and av_bsf_init()
4038	* from the new bitstream filtering API (using AVBSFContext).
4039	*/
4040	attribute_deprecated
4041	AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
4042	/**
4043	* @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4044	* is deprecated. Use av_bsf_send_packet() and av_bsf_receive_packet() from the
4045	* new bitstream filtering API (using AVBSFContext).
4046	*/
4047	attribute_deprecated
4048	int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
4049	AVCodecContext *avctx, const char *args,
4050	uint8_t **poutbuf, int *poutbuf_size,
4051	const uint8_t *buf, int buf_size, int keyframe);
4052	/**
4053	* @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4054	* is deprecated. Use av_bsf_free() from the new bitstream filtering API (using
4055	* AVBSFContext).
4056	*/
4057	attribute_deprecated
4058	void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
4059	/**
4060	* @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4061	* is deprecated. Use av_bsf_iterate() from the new bitstream filtering API (using
4062	* AVBSFContext).
4063	*/
4064	attribute_deprecated
4065	const AVBitStreamFilter *av_bitstream_filter_next(const AVBitStreamFilter *f);
4066	#endif
4067
4068	#if FF_API_NEXT
4069	attribute_deprecated
4070	const AVBitStreamFilter *av_bsf_next(void **opaque);
4071	#endif
4072
4073	/* memory */
4074
4075	/**
4076	* Same behaviour av_fast_malloc but the buffer has additional
4077	* AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
4078	*
4079	* In addition the whole buffer will initially and after resizes
4080	* be 0-initialized so that no uninitialized data will ever appear.
4081	*/
4082	void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
4083
4084	/**
4085	* Same behaviour av_fast_padded_malloc except that buffer will always
4086	* be 0-initialized after call.
4087	*/
4088	void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
4089
4090	/**
4091	* Encode extradata length to a buffer. Used by xiph codecs.
4092	*
4093	* @param s buffer to write to; must be at least (v/255+1) bytes long
4094	* @param v size of extradata in bytes
4095	* @return number of bytes written to the buffer.
4096	*/
4097	unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
4098
4099	#if FF_API_USER_VISIBLE_AVHWACCEL
4100	/**
4101	* Register the hardware accelerator hwaccel.
4102	*
4103	* @deprecated This function doesn't do anything.
4104	*/
4105	attribute_deprecated
4106	void av_register_hwaccel(AVHWAccel *hwaccel);
4107
4108	/**
4109	* If hwaccel is NULL, returns the first registered hardware accelerator,
4110	* if hwaccel is non-NULL, returns the next registered hardware accelerator
4111	* after hwaccel, or NULL if hwaccel is the last one.
4112	*
4113	* @deprecated AVHWaccel structures contain no user-serviceable parts, so
4114	* this function should not be used.
4115	*/
4116	attribute_deprecated
4117	AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel);
4118	#endif
4119
4120	#if FF_API_LOCKMGR
4121	/**
4122	* Lock operation used by lockmgr
4123	*
4124	* @deprecated Deprecated together with av_lockmgr_register().
4125	*/
4126	enum AVLockOp {
4127	AV_LOCK_CREATE, ///< Create a mutex
4128	AV_LOCK_OBTAIN, ///< Lock the mutex
4129	AV_LOCK_RELEASE, ///< Unlock the mutex
4130	AV_LOCK_DESTROY, ///< Free mutex resources
4131	};
4132
4133	/**
4134	* Register a user provided lock manager supporting the operations
4135	* specified by AVLockOp. The "mutex" argument to the function points
4136	* to a (void *) where the lockmgr should store/get a pointer to a user
4137	* allocated mutex. It is NULL upon AV_LOCK_CREATE and equal to the
4138	* value left by the last call for all other ops. If the lock manager is
4139	* unable to perform the op then it should leave the mutex in the same
4140	* state as when it was called and return a non-zero value. However,
4141	* when called with AV_LOCK_DESTROY the mutex will always be assumed to
4142	* have been successfully destroyed. If av_lockmgr_register succeeds
4143	* it will return a non-negative value, if it fails it will return a
4144	* negative value and destroy all mutex and unregister all callbacks.
4145	* av_lockmgr_register is not thread-safe, it must be called from a
4146	* single thread before any calls which make use of locking are used.
4147	*
4148	* @param cb User defined callback. av_lockmgr_register invokes calls
4149	* to this callback and the previously registered callback.
4150	* The callback will be used to create more than one mutex
4151	* each of which must be backed by its own underlying locking
4152	* mechanism (i.e. do not use a single static object to
4153	* implement your lock manager). If cb is set to NULL the
4154	* lockmgr will be unregistered.
4155	*
4156	* @deprecated This function does nothing, and always returns 0. Be sure to
4157	* build with thread support to get basic thread safety.
4158	*/
4159	attribute_deprecated
4160	int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
4161	#endif
4162
4163	/**
4164	* @return a positive value if s is open (i.e. avcodec_open2() was called on it
4165	* with no corresponding avcodec_close()), 0 otherwise.
4166	*/
4167	int avcodec_is_open(AVCodecContext *s);
4168
4169	/**
4170	* Allocate a CPB properties structure and initialize its fields to default
4171	* values.
4172	*
4173	* @param size if non-NULL, the size of the allocated struct will be written
4174	* here. This is useful for embedding it in side data.
4175	*
4176	* @return the newly allocated struct or NULL on failure
4177	*/
4178	AVCPBProperties *av_cpb_properties_alloc(size_t *size);
4179
4180	/**
4181	* @}
4182	*/
4183
4184	#endif /* AVCODEC_AVCODEC_H */
4185