2 * copyright (c) 2001 Fabrice Bellard
4 * This file is part of FFmpeg.
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.
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.
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
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
27 * Libavcodec external API header
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"
46 #include "codec_desc.h"
47 #include "codec_par.h"
53 * @defgroup libavc libavcodec
54 * Encoding/Decoding Library
58 * @defgroup lavc_decoding Decoding
62 * @defgroup lavc_encoding Encoding
66 * @defgroup lavc_codec Codecs
68 * @defgroup lavc_codec_native Native Codecs
71 * @defgroup lavc_codec_wrappers External library wrappers
74 * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
78 * @defgroup lavc_internal Internal
86 * @defgroup lavc_encdec send/receive encoding and decoding API overview
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.
93 * The API is very similar for encoding/decoding and audio/video, and works as
95 * - Set up and open the AVCodecContext as usual.
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.
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.
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.
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
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
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
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().
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.
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.
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
173 * - The new API does not handle subtitles yet.
175 * Mixing new and old function calls on the same AVCodecContext is not allowed,
176 * and will result in undefined behavior.
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.
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.
199 * @defgroup lavc_core Core functions/structures.
202 * Basic definitions, functions for querying libavcodec capabilities,
203 * allocating core structures, etc.
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.
215 #define AV_INPUT_BUFFER_PADDING_SIZE 64
218 * @ingroup lavc_encoding
219 * minimum encoding buffer size
220 * Used to avoid some checks during header writing.
222 #define AV_INPUT_BUFFER_MIN_SIZE 16384
225 * @ingroup lavc_decoding
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
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
253 * @ingroup lavc_encoding
255 typedef struct RcOverride{
258 int qscale; // If this is 0 then quality_factor will be used instead.
259 float quality_factor;
263 These flags can be passed in AVCodecContext.flags before initialization.
264 Note: Not everything is supported yet.
268 * Allow decoders to produce frames with data planes that are not aligned
269 * to CPU requirements (e.g. due to cropping).
271 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
275 #define AV_CODEC_FLAG_QSCALE (1 << 1)
277 * 4 MV per MB allowed / advanced prediction for H.263.
279 #define AV_CODEC_FLAG_4MV (1 << 2)
281 * Output even those frames that might be corrupted.
283 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
287 #define AV_CODEC_FLAG_QPEL (1 << 4)
289 * Don't output frames whose parameters differ from first
290 * decoded frame in stream.
292 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
294 * Use internal 2pass ratecontrol in first pass mode.
296 #define AV_CODEC_FLAG_PASS1 (1 << 9)
298 * Use internal 2pass ratecontrol in second pass mode.
300 #define AV_CODEC_FLAG_PASS2 (1 << 10)
304 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
306 * Only decode/encode grayscale.
308 #define AV_CODEC_FLAG_GRAY (1 << 13)
310 * error[?] variables will be set during encoding.
312 #define AV_CODEC_FLAG_PSNR (1 << 15)
314 * Input bitstream might be truncated at a random location
315 * instead of only at frame boundaries.
317 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
319 * Use interlaced DCT.
321 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
325 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
327 * Place global headers in extradata instead of every keyframe.
329 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
331 * Use only bitexact stuff (except (I)DCT).
333 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
334 /* Fx : Flag for H.263+ extra options */
336 * H.263 advanced intra coding / MPEG-4 AC prediction
338 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
340 * interlaced motion estimation
342 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
343 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
346 * Allow non spec compliant speedup tricks.
348 #define AV_CODEC_FLAG2_FAST (1 << 0)
350 * Skip bitstream encoding.
352 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
354 * Place global headers at every keyframe instead of in extradata.
356 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
359 * timecode is in drop frame format. DEPRECATED!!!!
361 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
364 * Input bitstream might be truncated at a packet boundaries
365 * instead of only at frame boundaries.
367 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
369 * Discard cropping information from SPS.
371 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
374 * Show all frames before the first keyframe
376 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
378 * Export motion vectors through frame side data
380 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
382 * Do not skip samples and export skip information as frame side data
384 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
386 * Do not reset ASS ReadOrder field on flush (subtitles decoding)
388 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
390 /* Unsupported options :
391 * Syntax Arithmetic coding (SAC)
392 * Reference Picture Selection
393 * Independent Segment Decoding */
395 /* codec capabilities */
397 /* Exported side data.
398 These flags can be passed in AVCodecContext.export_side_data before initialization.
401 * Export motion vectors through frame side data
403 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
405 * Export encoder Producer Reference Time through packet side data
407 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
410 * Export the AVVideoEncParams structure through frame side data.
412 #define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
415 * Do not apply film grain, export it instead.
417 #define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
421 * This specifies the area which should be displayed.
422 * Note there may be multiple such areas for one frame.
424 typedef struct AVPanScan {
427 * - encoding: Set by user.
428 * - decoding: Set by libavcodec.
433 * width and height in 1/16 pel
434 * - encoding: Set by user.
435 * - decoding: Set by libavcodec.
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.
445 int16_t position[3][2];
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.
453 typedef struct AVCPBProperties {
455 * Maximum bitrate of the stream, in bits per second.
456 * Zero if unknown or unspecified.
458 #if FF_API_UNSANITIZED_BITRATES
464 * Minimum bitrate of the stream, in bits per second.
465 * Zero if unknown or unspecified.
467 #if FF_API_UNSANITIZED_BITRATES
473 * Average bitrate of the stream, in bits per second.
474 * Zero if unknown or unspecified.
476 #if FF_API_UNSANITIZED_BITRATES
483 * The size of the buffer to which the ratecontrol is applied, in bits.
484 * Zero if unknown or unspecified.
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
493 * UINT64_MAX when unknown or unspecified.
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
503 typedef struct AVProducerReferenceTime {
505 * A UTC timestamp, in microseconds, since Unix epoch (e.g, av_gettime()).
509 } AVProducerReferenceTime;
512 * The decoder will keep a reference to the frame and may reuse it later.
514 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
517 * The encoder will keep a reference to the packet and may reuse it later.
519 #define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
521 struct AVCodecInternal;
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
528 * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
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*.
536 typedef struct AVCodecContext {
538 * information on struct for av_log
539 * - set by avcodec_alloc_context3
541 const AVClass *av_class;
542 int log_level_offset;
544 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
545 const struct AVCodec *codec;
546 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
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
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.
561 unsigned int codec_tag;
566 * Private context used for internal data.
568 * Unlike priv_data, this is not codec-specific. It is used in general
569 * libavcodec functions.
571 struct AVCodecInternal *internal;
574 * Private data of the user, can be used to carry app specific stuff.
575 * - encoding: Set by user.
576 * - decoding: Set by user.
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
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.
594 int bit_rate_tolerance;
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.
605 * - encoding: Set by user.
608 int compression_level;
609 #define FF_COMPRESSION_DEFAULT -1
613 * - encoding: Set by user.
614 * - decoding: Set by user.
620 * - encoding: Set by user.
621 * - decoding: Set by user.
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.
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
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
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)
655 * - encoding: MUST be set by user.
656 * - decoding: the use of this field for decoding is deprecated.
657 * Use framerate instead.
659 AVRational time_base;
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 ...
666 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
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.
679 * Number of frames the decoded output will be delayed relative to the
683 * For encoding, this field is unused (see initial_padding).
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.
689 * - encoding: Set by libavcodec.
690 * - decoding: Set by libavcodec.
697 * picture width / height.
699 * @note Those fields may not match the values of the last
700 * AVFrame output by avcodec_decode_video2 due frame
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.
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.
715 * @note Those field may not match the value of the last
716 * AVFrame output by avcodec_receive_frame() due frame
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.
724 int coded_width, coded_height;
727 * the number of pictures in a group of pictures, or 0 for intra_only
728 * - encoding: Set by user.
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.
738 * @note This field may not match the value of the last
739 * AVFrame output by avcodec_receive_frame() due frame
742 * - encoding: Set by user.
743 * - decoding: Set by user if known, overridden by libavcodec while
746 enum AVPixelFormat pix_fmt;
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
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
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
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
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);
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
786 * - decoding: Set by user, if not set the native format will be chosen.
788 enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
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.
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.
805 float b_quant_factor;
807 #if FF_API_PRIVATE_OPT
808 /** @deprecated use encoder private options instead */
810 int b_frame_strategy;
814 * qscale offset between IP and B-frames
815 * - encoding: Set by user.
818 float b_quant_offset;
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.
828 #if FF_API_PRIVATE_OPT
829 /** @deprecated use encoder private options instead */
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.
841 float i_quant_factor;
844 * qscale offset between P and I-frames
845 * - encoding: Set by user.
848 float i_quant_offset;
851 * luminance masking (0-> disabled)
852 * - encoding: Set by user.
858 * temporary complexity masking (0-> disabled)
859 * - encoding: Set by user.
862 float temporal_cplx_masking;
865 * spatial complexity masking (0-> disabled)
866 * - encoding: Set by user.
869 float spatial_cplx_masking;
872 * p block masking (0-> disabled)
873 * - encoding: Set by user.
879 * darkness masking (0-> disabled)
880 * - encoding: Set by user.
887 * - encoding: Set by libavcodec.
888 * - decoding: Set by user (or 0).
892 #if FF_API_PRIVATE_OPT
893 /** @deprecated use encoder private options instead */
895 int prediction_method;
896 #define FF_PRED_LEFT 0
897 #define FF_PRED_PLANE 1
898 #define FF_PRED_MEDIAN 2
902 * slice offsets in the frame in bytes
903 * - encoding: Set/allocated by libavcodec.
904 * - decoding: Set/allocated by user (or NULL).
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.
915 AVRational sample_aspect_ratio;
918 * motion estimation comparison function
919 * - encoding: Set by user.
924 * subpixel motion estimation comparison function
925 * - encoding: Set by user.
930 * macroblock comparison function (not supported yet)
931 * - encoding: Set by user.
936 * interlaced DCT comparison function
937 * - encoding: Set by user.
943 #define FF_CMP_SATD 2
945 #define FF_CMP_PSNR 4
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
960 * ME diamond size & shape
961 * - encoding: Set by user.
967 * amount of previous MV predictors (2a+1 x 2a+1 square)
968 * - encoding: Set by user.
971 int last_predictor_count;
973 #if FF_API_PRIVATE_OPT
974 /** @deprecated use encoder private options instead */
980 * motion estimation prepass comparison function
981 * - encoding: Set by user.
987 * ME prepass diamond size & shape
988 * - encoding: Set by user.
995 * - encoding: Set by user.
998 int me_subpel_quality;
1001 * maximum motion estimation search range in subpel units
1002 * If 0 then no limit.
1004 * - encoding: Set by user.
1005 * - decoding: unused
1011 * - encoding: unused
1012 * - decoding: Set by user.
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)
1020 * macroblock decision mode
1021 * - encoding: Set by user.
1022 * - decoding: unused
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
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.
1036 uint16_t *intra_matrix;
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.
1045 uint16_t *inter_matrix;
1047 #if FF_API_PRIVATE_OPT
1048 /** @deprecated use encoder private options instead */
1049 attribute_deprecated
1050 int scenechange_threshold;
1052 /** @deprecated use encoder private options instead */
1053 attribute_deprecated
1054 int noise_reduction;
1058 * precision of the intra DC coefficient - 8
1059 * - encoding: Set by user.
1060 * - decoding: Set by libavcodec
1062 int intra_dc_precision;
1065 * Number of macroblock rows at the top which are skipped.
1066 * - encoding: unused
1067 * - decoding: Set by user.
1072 * Number of macroblock rows at the bottom which are skipped.
1073 * - encoding: unused
1074 * - decoding: Set by user.
1079 * minimum MB Lagrange multiplier
1080 * - encoding: Set by user.
1081 * - decoding: unused
1086 * maximum MB Lagrange multiplier
1087 * - encoding: Set by user.
1088 * - decoding: unused
1092 #if FF_API_PRIVATE_OPT
1094 * @deprecated use encoder private options instead
1096 attribute_deprecated
1097 int me_penalty_compensation;
1101 * - encoding: Set by user.
1102 * - decoding: unused
1106 #if FF_API_PRIVATE_OPT
1107 /** @deprecated use encoder private options instead */
1108 attribute_deprecated
1114 * - encoding: Set by user.
1115 * - decoding: unused
1120 * number of reference frames
1121 * - encoding: Set by user.
1122 * - decoding: Set by lavc.
1126 #if FF_API_PRIVATE_OPT
1127 /** @deprecated use encoder private options instead */
1128 attribute_deprecated
1133 * Note: Value depends upon the compare function used for fullpel ME.
1134 * - encoding: Set by user.
1135 * - decoding: unused
1139 #if FF_API_PRIVATE_OPT
1140 /** @deprecated use encoder private options instead */
1141 attribute_deprecated
1146 * Chromaticity coordinates of the source primaries.
1147 * - encoding: Set by user
1148 * - decoding: Set by libavcodec
1150 enum AVColorPrimaries color_primaries;
1153 * Color Transfer Characteristic.
1154 * - encoding: Set by user
1155 * - decoding: Set by libavcodec
1157 enum AVColorTransferCharacteristic color_trc;
1160 * YUV colorspace type.
1161 * - encoding: Set by user
1162 * - decoding: Set by libavcodec
1164 enum AVColorSpace colorspace;
1167 * MPEG vs JPEG YUV range.
1168 * - encoding: Set by user
1169 * - decoding: Set by libavcodec
1171 enum AVColorRange color_range;
1174 * This defines the location of chroma samples.
1175 * - encoding: Set by user
1176 * - decoding: Set by libavcodec
1178 enum AVChromaLocation chroma_sample_location;
1182 * Indicates number of picture subdivisions. Used for parallelized
1184 * - encoding: Set by user
1185 * - decoding: unused
1190 * - encoding: set by libavcodec
1191 * - decoding: Set by user.
1193 enum AVFieldOrder field_order;
1196 int sample_rate; ///< samples per second
1197 int channels; ///< number of audio channels
1200 * audio sample format
1201 * - encoding: Set by user.
1202 * - decoding: Set by libavcodec.
1204 enum AVSampleFormat sample_fmt; ///< sample format
1206 /* The following data should not be initialized. */
1208 * Number of samples per channel in an audio frame.
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
1219 * Frame counter, set by libavcodec.
1221 * - decoding: total number of frames returned from the decoder so far.
1222 * - encoding: total number of frames passed to the encoder so far.
1224 * @note the counter is not incremented if encoding/decoding resulted in
1230 * number of bytes per packet if constant and known or 0
1231 * Used by some WAV based audio codecs.
1236 * Audio cutoff bandwidth (0 means "automatic")
1237 * - encoding: Set by user.
1238 * - decoding: unused
1243 * Audio channel layout.
1244 * - encoding: set by user.
1245 * - decoding: set by user, may be overwritten by libavcodec.
1247 uint64_t channel_layout;
1250 * Request decoder to use this channel layout if it can (0 for default)
1251 * - encoding: unused
1252 * - decoding: Set by user.
1254 uint64_t request_channel_layout;
1257 * Type of service that the audio stream conveys.
1258 * - encoding: Set by user.
1259 * - decoding: Set by libavcodec.
1261 enum AVAudioServiceType audio_service_type;
1264 * desired sample format
1265 * - encoding: Not used.
1266 * - decoding: Set by user.
1267 * Decoder will decode to this format if it can.
1269 enum AVSampleFormat request_sample_fmt;
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
1279 * The following fields will be set in the frame before this callback is
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.
1288 * This callback must fill the following fields in the frame:
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
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
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
1312 * Each data plane must be aligned to the maximum required by the target
1315 * @see avcodec_default_get_buffer2()
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.
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.
1325 * Some decoders do not support linesizes changing between frames.
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
1331 * @see avcodec_align_dimensions2()
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.
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.
1346 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1348 * - encoding: unused
1349 * - decoding: Set by libavcodec, user can override.
1351 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
1353 #if FF_API_OLD_ENCDEC
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.
1362 * This is always automatically enabled if avcodec_receive_frame() is used.
1364 * - encoding: unused
1365 * - decoding: set by the caller before avcodec_open2().
1367 attribute_deprecated
1368 int refcounted_frames;
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)
1377 * - encoding: Set by user.
1378 * - decoding: unused
1384 * - encoding: Set by user.
1385 * - decoding: unused
1390 * maximum quantizer difference between frames
1391 * - encoding: Set by user.
1392 * - decoding: unused
1397 * decoder bitstream buffer size
1398 * - encoding: Set by user.
1399 * - decoding: unused
1404 * ratecontrol override, see RcOverride
1405 * - encoding: Allocated/set/freed by user.
1406 * - decoding: unused
1408 int rc_override_count;
1409 RcOverride *rc_override;
1413 * - encoding: Set by user.
1414 * - decoding: Set by user, may be overwritten by libavcodec.
1416 int64_t rc_max_rate;
1420 * - encoding: Set by user.
1421 * - decoding: unused
1423 int64_t rc_min_rate;
1426 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1427 * - encoding: Set by user.
1428 * - decoding: unused.
1430 float rc_max_available_vbv_use;
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.
1437 float rc_min_vbv_overflow_use;
1440 * Number of bits which should be loaded into the rc buffer before decoding starts.
1441 * - encoding: Set by user.
1442 * - decoding: unused
1444 int rc_initial_buffer_occupancy;
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
1452 * @deprecated use encoder private options instead
1454 attribute_deprecated
1456 #endif /* FF_API_CODER_TYPE */
1458 #if FF_API_PRIVATE_OPT
1459 /** @deprecated use encoder private options instead */
1460 attribute_deprecated
1464 #if FF_API_PRIVATE_OPT
1465 /** @deprecated use encoder private options instead */
1466 attribute_deprecated
1467 int frame_skip_threshold;
1469 /** @deprecated use encoder private options instead */
1470 attribute_deprecated
1471 int frame_skip_factor;
1473 /** @deprecated use encoder private options instead */
1474 attribute_deprecated
1477 /** @deprecated use encoder private options instead */
1478 attribute_deprecated
1480 #endif /* FF_API_PRIVATE_OPT */
1483 * trellis RD quantization
1484 * - encoding: Set by user.
1485 * - decoding: unused
1489 #if FF_API_PRIVATE_OPT
1490 /** @deprecated use encoder private options instead */
1491 attribute_deprecated
1492 int min_prediction_order;
1494 /** @deprecated use encoder private options instead */
1495 attribute_deprecated
1496 int max_prediction_order;
1498 /** @deprecated use encoder private options instead */
1499 attribute_deprecated
1500 int64_t timecode_frame_start;
1503 #if FF_API_RTP_CALLBACK
1505 * @deprecated unused
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);
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. */
1529 * pass1 encoding statistics output buffer
1530 * - encoding: Set by libavcodec.
1531 * - decoding: unused
1536 * pass2 encoding statistics input buffer
1537 * Concatenated stuff from stats_out of pass1 should be placed here.
1538 * - encoding: Allocated/set/freed by user.
1539 * - decoding: unused
1544 * Work around bugs in encoders which sometimes cannot be detected automatically.
1545 * - encoding: Set by user
1546 * - decoding: Set by user
1548 int workaround_bugs;
1549 #define FF_BUG_AUTODETECT 1 ///< autodetection
1550 #define FF_BUG_XVID_ILACE 4
1551 #define FF_BUG_UMP4 8
1552 #define FF_BUG_NO_PADDING 16
1553 #define FF_BUG_AMV 32
1554 #define FF_BUG_QPEL_CHROMA 64
1555 #define FF_BUG_STD_QPEL 128
1556 #define FF_BUG_QPEL_CHROMA2 256
1557 #define FF_BUG_DIRECT_BLOCKSIZE 512
1558 #define FF_BUG_EDGE 1024
1559 #define FF_BUG_HPEL_CHROMA 2048
1560 #define FF_BUG_DC_CLIP 4096
1561 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1562 #define FF_BUG_TRUNCATED 16384
1563 #define FF_BUG_IEDGE 32768
1566 * strictly follow the standard (MPEG-4, ...).
1567 * - encoding: Set by user.
1568 * - decoding: Set by user.
1569 * Setting this to STRICT or higher means the encoder and decoder will
1570 * generally do stupid things, whereas setting it to unofficial or lower
1571 * will mean the encoder might produce output that is not supported by all
1572 * spec-compliant decoders. Decoders don't differentiate between normal,
1573 * unofficial and experimental (that is, they always try to decode things
1574 * when they can) unless they are explicitly asked to behave stupidly
1575 * (=strictly conform to the specs)
1577 int strict_std_compliance;
1578 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
1579 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
1580 #define FF_COMPLIANCE_NORMAL 0
1581 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
1582 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
1585 * error concealment flags
1586 * - encoding: unused
1587 * - decoding: Set by user.
1589 int error_concealment;
1590 #define FF_EC_GUESS_MVS 1
1591 #define FF_EC_DEBLOCK 2
1592 #define FF_EC_FAVOR_INTER 256
1596 * - encoding: Set by user.
1597 * - decoding: Set by user.
1600 #define FF_DEBUG_PICT_INFO 1
1601 #define FF_DEBUG_RC 2
1602 #define FF_DEBUG_BITSTREAM 4
1603 #define FF_DEBUG_MB_TYPE 8
1604 #define FF_DEBUG_QP 16
1605 #define FF_DEBUG_DCT_COEFF 0x00000040
1606 #define FF_DEBUG_SKIP 0x00000080
1607 #define FF_DEBUG_STARTCODE 0x00000100
1608 #define FF_DEBUG_ER 0x00000400
1609 #define FF_DEBUG_MMCO 0x00000800
1610 #define FF_DEBUG_BUGS 0x00001000
1611 #define FF_DEBUG_BUFFERS 0x00008000
1612 #define FF_DEBUG_THREADS 0x00010000
1613 #define FF_DEBUG_GREEN_MD 0x00800000
1614 #define FF_DEBUG_NOMC 0x01000000
1617 * Error recognition; may misdetect some more or less valid parts as errors.
1618 * - encoding: Set by user.
1619 * - decoding: Set by user.
1621 int err_recognition;
1624 * Verify checksums embedded in the bitstream (could be of either encoded or
1625 * decoded data, depending on the codec) and print an error message on mismatch.
1626 * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
1627 * decoder returning an error.
1629 #define AV_EF_CRCCHECK (1<<0)
1630 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
1631 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
1632 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
1634 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
1635 #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
1636 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
1637 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
1641 * opaque 64-bit number (generally a PTS) that will be reordered and
1642 * output in AVFrame.reordered_opaque
1643 * - encoding: Set by libavcodec to the reordered_opaque of the input
1644 * frame corresponding to the last returned packet. Only
1645 * supported by encoders with the
1646 * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1647 * - decoding: Set by user.
1649 int64_t reordered_opaque;
1652 * Hardware accelerator in use
1653 * - encoding: unused.
1654 * - decoding: Set by libavcodec
1656 const struct AVHWAccel *hwaccel;
1659 * Hardware accelerator context.
1660 * For some hardware accelerators, a global context needs to be
1661 * provided by the user. In that case, this holds display-dependent
1662 * data FFmpeg cannot instantiate itself. Please refer to the
1663 * FFmpeg HW accelerator documentation to know how to fill this
1664 * is. e.g. for VA API, this is a struct vaapi_context.
1665 * - encoding: unused
1666 * - decoding: Set by user
1668 void *hwaccel_context;
1672 * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1673 * - decoding: unused
1675 uint64_t error[AV_NUM_DATA_POINTERS];
1678 * DCT algorithm, see FF_DCT_* below
1679 * - encoding: Set by user.
1680 * - decoding: unused
1683 #define FF_DCT_AUTO 0
1684 #define FF_DCT_FASTINT 1
1685 #define FF_DCT_INT 2
1686 #define FF_DCT_MMX 3
1687 #define FF_DCT_ALTIVEC 5
1688 #define FF_DCT_FAAN 6
1691 * IDCT algorithm, see FF_IDCT_* below.
1692 * - encoding: Set by user.
1693 * - decoding: Set by user.
1696 #define FF_IDCT_AUTO 0
1697 #define FF_IDCT_INT 1
1698 #define FF_IDCT_SIMPLE 2
1699 #define FF_IDCT_SIMPLEMMX 3
1700 #define FF_IDCT_ARM 7
1701 #define FF_IDCT_ALTIVEC 8
1702 #define FF_IDCT_SIMPLEARM 10
1703 #define FF_IDCT_XVID 14
1704 #define FF_IDCT_SIMPLEARMV5TE 16
1705 #define FF_IDCT_SIMPLEARMV6 17
1706 #define FF_IDCT_FAAN 20
1707 #define FF_IDCT_SIMPLENEON 22
1708 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
1709 #define FF_IDCT_SIMPLEAUTO 128
1712 * bits per sample/pixel from the demuxer (needed for huffyuv).
1713 * - encoding: Set by libavcodec.
1714 * - decoding: Set by user.
1716 int bits_per_coded_sample;
1719 * Bits per sample/pixel of internal libavcodec pixel/sample format.
1720 * - encoding: set by user.
1721 * - decoding: set by libavcodec.
1723 int bits_per_raw_sample;
1726 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1727 * - encoding: unused
1728 * - decoding: Set by user.
1732 #if FF_API_CODED_FRAME
1734 * the picture in the bitstream
1735 * - encoding: Set by libavcodec.
1736 * - decoding: unused
1738 * @deprecated use the quality factor packet side data instead
1740 attribute_deprecated AVFrame *coded_frame;
1745 * is used to decide how many independent tasks should be passed to execute()
1746 * - encoding: Set by user.
1747 * - decoding: Set by user.
1752 * Which multithreading methods to use.
1753 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1754 * so clients which cannot provide future frames should not use it.
1756 * - encoding: Set by user, otherwise the default is used.
1757 * - decoding: Set by user, otherwise the default is used.
1760 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1761 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1764 * Which multithreading methods are in use by the codec.
1765 * - encoding: Set by libavcodec.
1766 * - decoding: Set by libavcodec.
1768 int active_thread_type;
1770 #if FF_API_THREAD_SAFE_CALLBACKS
1772 * Set by the client if its custom get_buffer() callback can be called
1773 * synchronously from another thread, which allows faster multithreaded decoding.
1774 * draw_horiz_band() will be called from other threads regardless of this setting.
1775 * Ignored if the default get_buffer() is used.
1776 * - encoding: Set by user.
1777 * - decoding: Set by user.
1779 * @deprecated the custom get_buffer2() callback should always be
1780 * thread-safe. Thread-unsafe get_buffer2() implementations will be
1781 * invalid starting with LIBAVCODEC_VERSION_MAJOR=60; in other words,
1782 * libavcodec will behave as if this field was always set to 1.
1783 * Callers that want to be forward compatible with future libavcodec
1784 * versions should wrap access to this field in
1785 * #if LIBAVCODEC_VERSION_MAJOR < 60
1787 attribute_deprecated
1788 int thread_safe_callbacks;
1792 * The codec may call this to execute several independent things.
1793 * It will return only after finishing all tasks.
1794 * The user may replace this with some multithreaded implementation,
1795 * the default implementation will execute the parts serially.
1796 * @param count the number of things to execute
1797 * - encoding: Set by libavcodec, user can override.
1798 * - decoding: Set by libavcodec, user can override.
1800 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1803 * The codec may call this to execute several independent things.
1804 * It will return only after finishing all tasks.
1805 * The user may replace this with some multithreaded implementation,
1806 * the default implementation will execute the parts serially.
1807 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
1808 * @param c context passed also to func
1809 * @param count the number of things to execute
1810 * @param arg2 argument passed unchanged to func
1811 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1812 * @param func function that will be called count times, with jobnr from 0 to count-1.
1813 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1814 * two instances of func executing at the same time will have the same threadnr.
1815 * @return always 0 currently, but code should handle a future improvement where when any call to func
1816 * returns < 0 no further calls to func may be done and < 0 is returned.
1817 * - encoding: Set by libavcodec, user can override.
1818 * - decoding: Set by libavcodec, user can override.
1820 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1823 * noise vs. sse weight for the nsse comparison function
1824 * - encoding: Set by user.
1825 * - decoding: unused
1831 * - encoding: Set by user.
1832 * - decoding: Set by libavcodec.
1835 #define FF_PROFILE_UNKNOWN -99
1836 #define FF_PROFILE_RESERVED -100
1838 #define FF_PROFILE_AAC_MAIN 0
1839 #define FF_PROFILE_AAC_LOW 1
1840 #define FF_PROFILE_AAC_SSR 2
1841 #define FF_PROFILE_AAC_LTP 3
1842 #define FF_PROFILE_AAC_HE 4
1843 #define FF_PROFILE_AAC_HE_V2 28
1844 #define FF_PROFILE_AAC_LD 22
1845 #define FF_PROFILE_AAC_ELD 38
1846 #define FF_PROFILE_MPEG2_AAC_LOW 128
1847 #define FF_PROFILE_MPEG2_AAC_HE 131
1849 #define FF_PROFILE_DNXHD 0
1850 #define FF_PROFILE_DNXHR_LB 1
1851 #define FF_PROFILE_DNXHR_SQ 2
1852 #define FF_PROFILE_DNXHR_HQ 3
1853 #define FF_PROFILE_DNXHR_HQX 4
1854 #define FF_PROFILE_DNXHR_444 5
1856 #define FF_PROFILE_DTS 20
1857 #define FF_PROFILE_DTS_ES 30
1858 #define FF_PROFILE_DTS_96_24 40
1859 #define FF_PROFILE_DTS_HD_HRA 50
1860 #define FF_PROFILE_DTS_HD_MA 60
1861 #define FF_PROFILE_DTS_EXPRESS 70
1863 #define FF_PROFILE_MPEG2_422 0
1864 #define FF_PROFILE_MPEG2_HIGH 1
1865 #define FF_PROFILE_MPEG2_SS 2
1866 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1867 #define FF_PROFILE_MPEG2_MAIN 4
1868 #define FF_PROFILE_MPEG2_SIMPLE 5
1870 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1871 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1873 #define FF_PROFILE_H264_BASELINE 66
1874 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1875 #define FF_PROFILE_H264_MAIN 77
1876 #define FF_PROFILE_H264_EXTENDED 88
1877 #define FF_PROFILE_H264_HIGH 100
1878 #define FF_PROFILE_H264_HIGH_10 110
1879 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1880 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1881 #define FF_PROFILE_H264_HIGH_422 122
1882 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1883 #define FF_PROFILE_H264_STEREO_HIGH 128
1884 #define FF_PROFILE_H264_HIGH_444 144
1885 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1886 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1887 #define FF_PROFILE_H264_CAVLC_444 44
1889 #define FF_PROFILE_VC1_SIMPLE 0
1890 #define FF_PROFILE_VC1_MAIN 1
1891 #define FF_PROFILE_VC1_COMPLEX 2
1892 #define FF_PROFILE_VC1_ADVANCED 3
1894 #define FF_PROFILE_MPEG4_SIMPLE 0
1895 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1896 #define FF_PROFILE_MPEG4_CORE 2
1897 #define FF_PROFILE_MPEG4_MAIN 3
1898 #define FF_PROFILE_MPEG4_N_BIT 4
1899 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1900 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1901 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1902 #define FF_PROFILE_MPEG4_HYBRID 8
1903 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1904 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1905 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1906 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1907 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1908 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1909 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1911 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1912 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1913 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1914 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1915 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1917 #define FF_PROFILE_VP9_0 0
1918 #define FF_PROFILE_VP9_1 1
1919 #define FF_PROFILE_VP9_2 2
1920 #define FF_PROFILE_VP9_3 3
1922 #define FF_PROFILE_HEVC_MAIN 1
1923 #define FF_PROFILE_HEVC_MAIN_10 2
1924 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1925 #define FF_PROFILE_HEVC_REXT 4
1927 #define FF_PROFILE_VVC_MAIN_10 1
1928 #define FF_PROFILE_VVC_MAIN_10_444 33
1930 #define FF_PROFILE_AV1_MAIN 0
1931 #define FF_PROFILE_AV1_HIGH 1
1932 #define FF_PROFILE_AV1_PROFESSIONAL 2
1934 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1935 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1936 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1937 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1938 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1940 #define FF_PROFILE_SBC_MSBC 1
1942 #define FF_PROFILE_PRORES_PROXY 0
1943 #define FF_PROFILE_PRORES_LT 1
1944 #define FF_PROFILE_PRORES_STANDARD 2
1945 #define FF_PROFILE_PRORES_HQ 3
1946 #define FF_PROFILE_PRORES_4444 4
1947 #define FF_PROFILE_PRORES_XQ 5
1949 #define FF_PROFILE_ARIB_PROFILE_A 0
1950 #define FF_PROFILE_ARIB_PROFILE_C 1
1952 #define FF_PROFILE_KLVA_SYNC 0
1953 #define FF_PROFILE_KLVA_ASYNC 1
1957 * - encoding: Set by user.
1958 * - decoding: Set by libavcodec.
1961 #define FF_LEVEL_UNKNOWN -99
1964 * Skip loop filtering for selected frames.
1965 * - encoding: unused
1966 * - decoding: Set by user.
1968 enum AVDiscard skip_loop_filter;
1971 * Skip IDCT/dequantization for selected frames.
1972 * - encoding: unused
1973 * - decoding: Set by user.
1975 enum AVDiscard skip_idct;
1978 * Skip decoding for selected frames.
1979 * - encoding: unused
1980 * - decoding: Set by user.
1982 enum AVDiscard skip_frame;
1985 * Header containing style information for text subtitles.
1986 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
1987 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
1988 * the Format line following. It shouldn't include any Dialogue line.
1989 * - encoding: Set/allocated/freed by user (before avcodec_open2())
1990 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
1992 uint8_t *subtitle_header;
1993 int subtitle_header_size;
1995 #if FF_API_VBV_DELAY
1997 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
1998 * Used for compliant TS muxing.
1999 * - encoding: Set by libavcodec.
2000 * - decoding: unused.
2001 * @deprecated this value is now exported as a part of
2002 * AV_PKT_DATA_CPB_PROPERTIES packet side data
2004 attribute_deprecated
2009 * Audio only. The number of "priming" samples (padding) inserted by the
2010 * encoder at the beginning of the audio. I.e. this number of leading
2011 * decoded samples must be discarded by the caller to get the original audio
2012 * without leading padding.
2014 * - decoding: unused
2015 * - encoding: Set by libavcodec. The timestamps on the output packets are
2016 * adjusted by the encoder so that they always refer to the
2017 * first sample of the data actually contained in the packet,
2018 * including any added padding. E.g. if the timebase is
2019 * 1/samplerate and the timestamp of the first input sample is
2020 * 0, the timestamp of the first output packet will be
2023 int initial_padding;
2026 * - decoding: For codecs that store a framerate value in the compressed
2027 * bitstream, the decoder may export it here. { 0, 1} when
2029 * - encoding: May be used to signal the framerate of CFR content to an
2032 AVRational framerate;
2035 * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
2036 * - encoding: unused.
2037 * - decoding: Set by libavcodec before calling get_format()
2039 enum AVPixelFormat sw_pix_fmt;
2042 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
2043 * - encoding unused.
2044 * - decoding set by user.
2046 AVRational pkt_timebase;
2050 * - encoding: unused.
2051 * - decoding: set by libavcodec.
2053 const AVCodecDescriptor *codec_descriptor;
2056 * Current statistics for PTS correction.
2057 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
2058 * - encoding: unused
2060 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
2061 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
2062 int64_t pts_correction_last_pts; /// PTS of the last frame
2063 int64_t pts_correction_last_dts; /// DTS of the last frame
2066 * Character encoding of the input subtitles file.
2067 * - decoding: set by user
2068 * - encoding: unused
2073 * Subtitles character encoding mode. Formats or codecs might be adjusting
2074 * this setting (if they are doing the conversion themselves for instance).
2075 * - decoding: set by libavcodec
2076 * - encoding: unused
2078 int sub_charenc_mode;
2079 #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)
2080 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
2081 #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
2082 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
2085 * Skip processing alpha if supported by codec.
2086 * Note that if the format uses pre-multiplied alpha (common with VP6,
2087 * and recommended due to better video quality/compression)
2088 * the image will look as if alpha-blended onto a black background.
2089 * However for formats that do not use pre-multiplied alpha
2090 * there might be serious artefacts (though e.g. libswscale currently
2091 * assumes pre-multiplied alpha anyway).
2093 * - decoding: set by user
2094 * - encoding: unused
2099 * Number of samples to skip after a discontinuity
2100 * - decoding: unused
2101 * - encoding: set by libavcodec
2107 * @deprecated unused
2109 attribute_deprecated
2111 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
2112 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
2113 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2117 * custom intra quantization matrix
2118 * - encoding: Set by user, can be NULL.
2119 * - decoding: unused.
2121 uint16_t *chroma_intra_matrix;
2124 * dump format separator.
2125 * can be ", " or "\n " or anything else
2126 * - encoding: Set by user.
2127 * - decoding: Set by user.
2129 uint8_t *dump_separator;
2132 * ',' separated list of allowed decoders.
2133 * If NULL then all are allowed
2134 * - encoding: unused
2135 * - decoding: set by user
2137 char *codec_whitelist;
2140 * Properties of the stream that gets decoded
2141 * - encoding: unused
2142 * - decoding: set by libavcodec
2144 unsigned properties;
2145 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
2146 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
2149 * Additional data associated with the entire coded stream.
2151 * - decoding: unused
2152 * - encoding: may be set by libavcodec after avcodec_open2().
2154 AVPacketSideData *coded_side_data;
2155 int nb_coded_side_data;
2158 * A reference to the AVHWFramesContext describing the input (for encoding)
2159 * or output (decoding) frames. The reference is set by the caller and
2160 * afterwards owned (and freed) by libavcodec - it should never be read by
2161 * the caller after being set.
2163 * - decoding: This field should be set by the caller from the get_format()
2164 * callback. The previous reference (if any) will always be
2165 * unreffed by libavcodec before the get_format() call.
2167 * If the default get_buffer2() is used with a hwaccel pixel
2168 * format, then this AVHWFramesContext will be used for
2169 * allocating the frame buffers.
2171 * - encoding: For hardware encoders configured to use a hwaccel pixel
2172 * format, this field should be set by the caller to a reference
2173 * to the AVHWFramesContext describing input frames.
2174 * AVHWFramesContext.format must be equal to
2175 * AVCodecContext.pix_fmt.
2177 * This field should be set before avcodec_open2() is called.
2179 AVBufferRef *hw_frames_ctx;
2182 * Control the form of AVSubtitle.rects[N]->ass
2183 * - decoding: set by user
2184 * - encoding: unused
2186 int sub_text_format;
2187 #define FF_SUB_TEXT_FMT_ASS 0
2188 #if FF_API_ASS_TIMING
2189 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
2193 * Audio only. The amount of padding (in samples) appended by the encoder to
2194 * the end of the audio. I.e. this number of decoded samples must be
2195 * discarded by the caller from the end of the stream to get the original
2196 * audio without any trailing padding.
2198 * - decoding: unused
2199 * - encoding: unused
2201 int trailing_padding;
2204 * The number of pixels per image to maximally accept.
2206 * - decoding: set by user
2207 * - encoding: set by user
2212 * A reference to the AVHWDeviceContext describing the device which will
2213 * be used by a hardware encoder/decoder. The reference is set by the
2214 * caller and afterwards owned (and freed) by libavcodec.
2216 * This should be used if either the codec device does not require
2217 * hardware frames or any that are used are to be allocated internally by
2218 * libavcodec. If the user wishes to supply any of the frames used as
2219 * encoder input or decoder output then hw_frames_ctx should be used
2220 * instead. When hw_frames_ctx is set in get_format() for a decoder, this
2221 * field will be ignored while decoding the associated stream segment, but
2222 * may again be used on a following one after another get_format() call.
2224 * For both encoders and decoders this field should be set before
2225 * avcodec_open2() is called and must not be written to thereafter.
2227 * Note that some decoders may require this field to be set initially in
2228 * order to support hw_frames_ctx at all - in that case, all frames
2229 * contexts used must be created on the same device.
2231 AVBufferRef *hw_device_ctx;
2234 * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
2235 * decoding (if active).
2236 * - encoding: unused
2237 * - decoding: Set by user (either before avcodec_open2(), or in the
2238 * AVCodecContext.get_format callback)
2243 * Video decoding only. Certain video codecs support cropping, meaning that
2244 * only a sub-rectangle of the decoded frame is intended for display. This
2245 * option controls how cropping is handled by libavcodec.
2247 * When set to 1 (the default), libavcodec will apply cropping internally.
2248 * I.e. it will modify the output frame width/height fields and offset the
2249 * data pointers (only by as much as possible while preserving alignment, or
2250 * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
2251 * the frames output by the decoder refer only to the cropped area. The
2252 * crop_* fields of the output frames will be zero.
2254 * When set to 0, the width/height fields of the output frames will be set
2255 * to the coded dimensions and the crop_* fields will describe the cropping
2256 * rectangle. Applying the cropping is left to the caller.
2258 * @warning When hardware acceleration with opaque output frames is used,
2259 * libavcodec is unable to apply cropping from the top/left border.
2261 * @note when this option is set to zero, the width/height fields of the
2262 * AVCodecContext and output AVFrames have different meanings. The codec
2263 * context fields store display dimensions (with the coded dimensions in
2264 * coded_width/height), while the frame fields store the coded dimensions
2265 * (with the display dimensions being determined by the crop_* fields).
2270 * Video decoding only. Sets the number of extra hardware frames which
2271 * the decoder will allocate for use by the caller. This must be set
2272 * before avcodec_open2() is called.
2274 * Some hardware decoders require all frames that they will use for
2275 * output to be defined in advance before decoding starts. For such
2276 * decoders, the hardware frame pool must therefore be of a fixed size.
2277 * The extra frames set here are on top of any number that the decoder
2278 * needs internally in order to operate normally (for example, frames
2279 * used as reference pictures).
2281 int extra_hw_frames;
2284 * The percentage of damaged samples to discard a frame.
2286 * - decoding: set by user
2287 * - encoding: unused
2289 int discard_damaged_percentage;
2292 * The number of samples per frame to maximally accept.
2294 * - decoding: set by user
2295 * - encoding: set by user
2297 int64_t max_samples;
2300 * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
2301 * metadata exported in frame, packet, or coded stream side data by
2302 * decoders and encoders.
2304 * - decoding: set by user
2305 * - encoding: set by user
2307 int export_side_data;
2310 * This callback is called at the beginning of each packet to get a data
2313 * The following field will be set in the packet before this callback is
2316 * This callback must use the above value to calculate the required buffer size,
2317 * which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
2319 * This callback must fill the following fields in the packet:
2320 * - data: alignment requirements for AVPacket apply, if any. Some architectures and
2321 * encoders may benefit from having aligned data.
2322 * - buf: must contain a pointer to an AVBufferRef structure. The packet's
2323 * data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
2324 * and av_buffer_ref().
2326 * If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2327 * avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2330 * The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2331 * They may be used for example to hint what use the buffer may get after being
2333 * Implementations of this callback may ignore flags they don't understand.
2334 * If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2335 * (read and/or written to if it is writable) later by libavcodec.
2337 * This callback must be thread-safe, as when frame threading is used, it may
2338 * be called from multiple threads simultaneously.
2340 * @see avcodec_default_get_encode_buffer()
2342 * - encoding: Set by libavcodec, user can override.
2343 * - decoding: unused
2345 int (*get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags);
2348 #if FF_API_CODEC_GET_SET
2350 * Accessors for some AVCodecContext fields. These used to be provided for ABI
2351 * compatibility, and do not need to be used anymore.
2353 attribute_deprecated
2354 AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
2355 attribute_deprecated
2356 void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
2358 attribute_deprecated
2359 const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
2360 attribute_deprecated
2361 void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
2363 attribute_deprecated
2364 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
2366 attribute_deprecated
2367 int av_codec_get_lowres(const AVCodecContext *avctx);
2368 attribute_deprecated
2369 void av_codec_set_lowres(AVCodecContext *avctx, int val);
2371 attribute_deprecated
2372 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
2373 attribute_deprecated
2374 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
2376 attribute_deprecated
2377 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
2378 attribute_deprecated
2379 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
2384 #if FF_API_CODEC_GET_SET
2385 attribute_deprecated
2386 int av_codec_get_max_lowres(const AVCodec *codec);
2389 struct MpegEncContext;
2392 * @defgroup lavc_hwaccel AVHWAccel
2394 * @note Nothing in this structure should be accessed by the user. At some
2395 * point in future it will not be externally visible at all.
2399 typedef struct AVHWAccel {
2401 * Name of the hardware accelerated codec.
2402 * The name is globally unique among encoders and among decoders (but an
2403 * encoder and a decoder can share the same name).
2408 * Type of codec implemented by the hardware accelerator.
2410 * See AVMEDIA_TYPE_xxx
2412 enum AVMediaType type;
2415 * Codec implemented by the hardware accelerator.
2417 * See AV_CODEC_ID_xxx
2422 * Supported pixel format.
2424 * Only hardware accelerated formats are supported here.
2426 enum AVPixelFormat pix_fmt;
2429 * Hardware accelerated codec capabilities.
2430 * see AV_HWACCEL_CODEC_CAP_*
2434 /*****************************************************************
2435 * No fields below this line are part of the public API. They
2436 * may not be used outside of libavcodec and can be changed and
2438 * New public fields should be added right above.
2439 *****************************************************************
2443 * Allocate a custom buffer
2445 int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
2448 * Called at the beginning of each frame or field picture.
2450 * Meaningful frame information (codec specific) is guaranteed to
2451 * be parsed at this point. This function is mandatory.
2453 * Note that buf can be NULL along with buf_size set to 0.
2454 * Otherwise, this means the whole frame is available at this point.
2456 * @param avctx the codec context
2457 * @param buf the frame data buffer base
2458 * @param buf_size the size of the frame in bytes
2459 * @return zero if successful, a negative value otherwise
2461 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2464 * Callback for parameter data (SPS/PPS/VPS etc).
2466 * Useful for hardware decoders which keep persistent state about the
2467 * video parameters, and need to receive any changes to update that state.
2469 * @param avctx the codec context
2470 * @param type the nal unit type
2471 * @param buf the nal unit data buffer
2472 * @param buf_size the size of the nal unit in bytes
2473 * @return zero if successful, a negative value otherwise
2475 int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
2478 * Callback for each slice.
2480 * Meaningful slice information (codec specific) is guaranteed to
2481 * be parsed at this point. This function is mandatory.
2482 * The only exception is XvMC, that works on MB level.
2484 * @param avctx the codec context
2485 * @param buf the slice data buffer base
2486 * @param buf_size the size of the slice in bytes
2487 * @return zero if successful, a negative value otherwise
2489 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2492 * Called at the end of each frame or field picture.
2494 * The whole picture is parsed at this point and can now be sent
2495 * to the hardware accelerator. This function is mandatory.
2497 * @param avctx the codec context
2498 * @return zero if successful, a negative value otherwise
2500 int (*end_frame)(AVCodecContext *avctx);
2503 * Size of per-frame hardware accelerator private data.
2505 * Private data is allocated with av_mallocz() before
2506 * AVCodecContext.get_buffer() and deallocated after
2507 * AVCodecContext.release_buffer().
2509 int frame_priv_data_size;
2512 * Called for every Macroblock in a slice.
2514 * XvMC uses it to replace the ff_mpv_reconstruct_mb().
2515 * Instead of decoding to raw picture, MB parameters are
2516 * stored in an array provided by the video driver.
2518 * @param s the mpeg context
2520 void (*decode_mb)(struct MpegEncContext *s);
2523 * Initialize the hwaccel private data.
2525 * This will be called from ff_get_format(), after hwaccel and
2526 * hwaccel_context are set and the hwaccel private data in AVCodecInternal
2529 int (*init)(AVCodecContext *avctx);
2532 * Uninitialize the hwaccel private data.
2534 * This will be called from get_format() or avcodec_close(), after hwaccel
2535 * and hwaccel_context are already uninitialized.
2537 int (*uninit)(AVCodecContext *avctx);
2540 * Size of the private data to allocate in
2541 * AVCodecInternal.hwaccel_priv_data.
2546 * Internal hwaccel capabilities.
2551 * Fill the given hw_frames context with current codec parameters. Called
2552 * from get_format. Refer to avcodec_get_hw_frames_parameters() for
2555 * This CAN be called before AVHWAccel.init is called, and you must assume
2556 * that avctx->hwaccel_priv_data is invalid.
2558 int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
2562 * HWAccel is experimental and is thus avoided in favor of non experimental
2565 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2568 * Hardware acceleration should be used for decoding even if the codec level
2569 * used is unknown or higher than the maximum supported level reported by the
2572 * It's generally a good idea to pass this flag unless you have a specific
2573 * reason not to, as hardware tends to under-report supported levels.
2575 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2578 * Hardware acceleration can output YUV pixel formats with a different chroma
2579 * sampling than 4:2:0 and/or other than 8 bits per component.
2581 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2584 * Hardware acceleration should still be attempted for decoding when the
2585 * codec profile does not match the reported capabilities of the hardware.
2587 * For example, this can be used to try to decode baseline profile H.264
2588 * streams in hardware - it will often succeed, because many streams marked
2589 * as baseline profile actually conform to constrained baseline profile.
2591 * @warning If the stream is actually not supported then the behaviour is
2592 * undefined, and may include returning entirely incorrect output
2593 * while indicating success.
2595 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2601 #if FF_API_AVPICTURE
2603 * @defgroup lavc_picture AVPicture
2605 * Functions for working with AVPicture
2610 * Picture data structure.
2612 * Up to four components can be stored into it, the last component is
2614 * @deprecated use AVFrame or imgutils functions instead
2616 typedef struct AVPicture {
2617 attribute_deprecated
2618 uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
2619 attribute_deprecated
2620 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
2628 enum AVSubtitleType {
2631 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2634 * Plain text, the text field must be set by the decoder and is
2635 * authoritative. ass and pict fields may contain approximations.
2640 * Formatted text, the ass field must be set by the decoder and is
2641 * authoritative. pict and text fields may contain approximations.
2646 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
2648 typedef struct AVSubtitleRect {
2649 int x; ///< top left corner of pict, undefined when pict is not set
2650 int y; ///< top left corner of pict, undefined when pict is not set
2651 int w; ///< width of pict, undefined when pict is not set
2652 int h; ///< height of pict, undefined when pict is not set
2653 int nb_colors; ///< number of colors in pict, undefined when pict is not set
2655 #if FF_API_AVPICTURE
2657 * @deprecated unused
2659 attribute_deprecated
2663 * data+linesize for the bitmap of this subtitle.
2664 * Can be set for text/ass as well once they are rendered.
2669 enum AVSubtitleType type;
2671 char *text; ///< 0 terminated plain UTF-8 text
2674 * 0 terminated ASS/SSA compatible event line.
2675 * The presentation of this is unaffected by the other values in this
2683 typedef struct AVSubtitle {
2684 uint16_t format; /* 0 = graphics */
2685 uint32_t start_display_time; /* relative to packet pts, in ms */
2686 uint32_t end_display_time; /* relative to packet pts, in ms */
2688 AVSubtitleRect **rects;
2689 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2693 * Return the LIBAVCODEC_VERSION_INT constant.
2695 unsigned avcodec_version(void);
2698 * Return the libavcodec build-time configuration.
2700 const char *avcodec_configuration(void);
2703 * Return the libavcodec license.
2705 const char *avcodec_license(void);
2708 * Allocate an AVCodecContext and set its fields to default values. The
2709 * resulting struct should be freed with avcodec_free_context().
2711 * @param codec if non-NULL, allocate private data and initialize defaults
2712 * for the given codec. It is illegal to then call avcodec_open2()
2713 * with a different codec.
2714 * If NULL, then the codec-specific defaults won't be initialized,
2715 * which may result in suboptimal default settings (this is
2716 * important mainly for encoders, e.g. libx264).
2718 * @return An AVCodecContext filled with default values or NULL on failure.
2720 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
2723 * Free the codec context and everything associated with it and write NULL to
2724 * the provided pointer.
2726 void avcodec_free_context(AVCodecContext **avctx);
2728 #if FF_API_GET_CONTEXT_DEFAULTS
2730 * @deprecated This function should not be used, as closing and opening a codec
2731 * context multiple time is not supported. A new codec context should be
2732 * allocated for each new use.
2734 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
2738 * Get the AVClass for AVCodecContext. It can be used in combination with
2739 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2741 * @see av_opt_find().
2743 const AVClass *avcodec_get_class(void);
2745 #if FF_API_GET_FRAME_CLASS
2747 * @deprecated This function should not be used.
2749 attribute_deprecated
2750 const AVClass *avcodec_get_frame_class(void);
2754 * Get the AVClass for AVSubtitleRect. It can be used in combination with
2755 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2757 * @see av_opt_find().
2759 const AVClass *avcodec_get_subtitle_rect_class(void);
2761 #if FF_API_COPY_CONTEXT
2763 * Copy the settings of the source AVCodecContext into the destination
2764 * AVCodecContext. The resulting destination codec context will be
2765 * unopened, i.e. you are required to call avcodec_open2() before you
2766 * can use this AVCodecContext to decode/encode video/audio data.
2768 * @param dest target codec context, should be initialized with
2769 * avcodec_alloc_context3(NULL), but otherwise uninitialized
2770 * @param src source codec context
2771 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
2773 * @deprecated The semantics of this function are ill-defined and it should not
2774 * be used. If you need to transfer the stream parameters from one codec context
2775 * to another, use an intermediate AVCodecParameters instance and the
2776 * avcodec_parameters_from_context() / avcodec_parameters_to_context()
2779 attribute_deprecated
2780 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
2784 * Fill the parameters struct based on the values from the supplied codec
2785 * context. Any allocated fields in par are freed and replaced with duplicates
2786 * of the corresponding fields in codec.
2788 * @return >= 0 on success, a negative AVERROR code on failure
2790 int avcodec_parameters_from_context(AVCodecParameters *par,
2791 const AVCodecContext *codec);
2794 * Fill the codec context based on the values from the supplied codec
2795 * parameters. Any allocated fields in codec that have a corresponding field in
2796 * par are freed and replaced with duplicates of the corresponding field in par.
2797 * Fields in codec that do not have a counterpart in par are not touched.
2799 * @return >= 0 on success, a negative AVERROR code on failure.
2801 int avcodec_parameters_to_context(AVCodecContext *codec,
2802 const AVCodecParameters *par);
2805 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2806 * function the context has to be allocated with avcodec_alloc_context3().
2808 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2809 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2810 * retrieving a codec.
2812 * @warning This function is not thread safe!
2814 * @note Always call this function before using decoding routines (such as
2815 * @ref avcodec_receive_frame()).
2818 * av_dict_set(&opts, "b", "2.5M", 0);
2819 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2823 * context = avcodec_alloc_context3(codec);
2825 * if (avcodec_open2(context, codec, opts) < 0)
2829 * @param avctx The context to initialize.
2830 * @param codec The codec to open this context for. If a non-NULL codec has been
2831 * previously passed to avcodec_alloc_context3() or
2832 * for this context, then this parameter MUST be either NULL or
2833 * equal to the previously passed codec.
2834 * @param options A dictionary filled with AVCodecContext and codec-private options.
2835 * On return this object will be filled with options that were not found.
2837 * @return zero on success, a negative value on error
2838 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2839 * av_dict_set(), av_opt_find().
2841 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2844 * Close a given AVCodecContext and free all the data associated with it
2845 * (but not the AVCodecContext itself).
2847 * Calling this function on an AVCodecContext that hasn't been opened will free
2848 * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2849 * codec. Subsequent calls will do nothing.
2851 * @note Do not use this function. Use avcodec_free_context() to destroy a
2852 * codec context (either open or closed). Opening and closing a codec context
2853 * multiple times is not supported anymore -- use multiple codec contexts
2856 int avcodec_close(AVCodecContext *avctx);
2859 * Free all allocated data in the given subtitle struct.
2861 * @param sub AVSubtitle to free.
2863 void avsubtitle_free(AVSubtitle *sub);
2870 * @addtogroup lavc_decoding
2875 * The default callback for AVCodecContext.get_buffer2(). It is made public so
2876 * it can be called by custom get_buffer2() implementations for decoders without
2877 * AV_CODEC_CAP_DR1 set.
2879 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
2882 * The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2883 * it can be called by custom get_encode_buffer() implementations for encoders without
2884 * AV_CODEC_CAP_DR1 set.
2886 int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags);
2889 * Modify width and height values so that they will result in a memory
2890 * buffer that is acceptable for the codec if you do not use any horizontal
2893 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2895 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
2898 * Modify width and height values so that they will result in a memory
2899 * buffer that is acceptable for the codec if you also ensure that all
2900 * line sizes are a multiple of the respective linesize_align[i].
2902 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2904 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
2905 int linesize_align[AV_NUM_DATA_POINTERS]);
2908 * Converts AVChromaLocation to swscale x/y chroma position.
2910 * The positions represent the chroma (0,0) position in a coordinates system
2911 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2913 * @param xpos horizontal chroma sample position
2914 * @param ypos vertical chroma sample position
2916 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
2919 * Converts swscale x/y chroma position to AVChromaLocation.
2921 * The positions represent the chroma (0,0) position in a coordinates system
2922 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2924 * @param xpos horizontal chroma sample position
2925 * @param ypos vertical chroma sample position
2927 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
2929 #if FF_API_OLD_ENCDEC
2931 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
2933 * Some decoders may support multiple frames in a single AVPacket. Such
2934 * decoders would then just decode the first frame and the return value would be
2935 * less than the packet size. In this case, avcodec_decode_audio4 has to be
2936 * called again with an AVPacket containing the remaining data in order to
2937 * decode the second frame, etc... Even if no frames are returned, the packet
2938 * needs to be fed to the decoder with remaining data until it is completely
2939 * consumed or an error occurs.
2941 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2942 * and output. This means that for some packets they will not immediately
2943 * produce decoded output and need to be flushed at the end of decoding to get
2944 * all the decoded data. Flushing is done by calling this function with packets
2945 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2946 * returning samples. It is safe to flush even those decoders that are not
2947 * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
2949 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2950 * larger than the actual read bytes because some optimized bitstream
2951 * readers read 32 or 64 bits at once and could read over the end.
2953 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2954 * before packets may be fed to the decoder.
2956 * @param avctx the codec context
2957 * @param[out] frame The AVFrame in which to store decoded audio samples.
2958 * The decoder will allocate a buffer for the decoded frame by
2959 * calling the AVCodecContext.get_buffer2() callback.
2960 * When AVCodecContext.refcounted_frames is set to 1, the frame is
2961 * reference counted and the returned reference belongs to the
2962 * caller. The caller must release the frame using av_frame_unref()
2963 * when the frame is no longer needed. The caller may safely write
2964 * to the frame if av_frame_is_writable() returns 1.
2965 * When AVCodecContext.refcounted_frames is set to 0, the returned
2966 * reference belongs to the decoder and is valid only until the
2967 * next call to this function or until closing or flushing the
2968 * decoder. The caller may not write to it.
2969 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
2970 * non-zero. Note that this field being set to zero
2971 * does not mean that an error has occurred. For
2972 * decoders with AV_CODEC_CAP_DELAY set, no given decode
2973 * call is guaranteed to produce a frame.
2974 * @param[in] avpkt The input AVPacket containing the input buffer.
2975 * At least avpkt->data and avpkt->size should be set. Some
2976 * decoders might also require additional fields to be set.
2977 * @return A negative error code is returned if an error occurred during
2978 * decoding, otherwise the number of bytes consumed from the input
2979 * AVPacket is returned.
2981 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
2983 attribute_deprecated
2984 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
2985 int *got_frame_ptr, const AVPacket *avpkt);
2988 * Decode the video frame of size avpkt->size from avpkt->data into picture.
2989 * Some decoders may support multiple frames in a single AVPacket, such
2990 * decoders would then just decode the first frame.
2992 * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
2993 * the actual read bytes because some optimized bitstream readers read 32 or 64
2994 * bits at once and could read over the end.
2996 * @warning The end of the input buffer buf should be set to 0 to ensure that
2997 * no overreading happens for damaged MPEG streams.
2999 * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
3000 * between input and output, these need to be fed with avpkt->data=NULL,
3001 * avpkt->size=0 at the end to return the remaining frames.
3003 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3004 * before packets may be fed to the decoder.
3006 * @param avctx the codec context
3007 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
3008 * Use av_frame_alloc() to get an AVFrame. The codec will
3009 * allocate memory for the actual bitmap by calling the
3010 * AVCodecContext.get_buffer2() callback.
3011 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3012 * reference counted and the returned reference belongs to the
3013 * caller. The caller must release the frame using av_frame_unref()
3014 * when the frame is no longer needed. The caller may safely write
3015 * to the frame if av_frame_is_writable() returns 1.
3016 * When AVCodecContext.refcounted_frames is set to 0, the returned
3017 * reference belongs to the decoder and is valid only until the
3018 * next call to this function or until closing or flushing the
3019 * decoder. The caller may not write to it.
3021 * @param[in] avpkt The input AVPacket containing the input buffer.
3022 * You can create such packet with av_init_packet() and by then setting
3023 * data and size, some decoders might in addition need other fields like
3024 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
3026 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
3027 * @return On error a negative value is returned, otherwise the number of bytes
3028 * used or zero if no frame could be decompressed.
3030 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
3032 attribute_deprecated
3033 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
3034 int *got_picture_ptr,
3035 const AVPacket *avpkt);
3039 * Decode a subtitle message.
3040 * Return a negative value on error, otherwise return the number of bytes used.
3041 * If no subtitle could be decompressed, got_sub_ptr is zero.
3042 * Otherwise, the subtitle is stored in *sub.
3043 * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
3044 * simplicity, because the performance difference is expected to be negligible
3045 * and reusing a get_buffer written for video codecs would probably perform badly
3046 * due to a potentially very different allocation pattern.
3048 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
3049 * and output. This means that for some packets they will not immediately
3050 * produce decoded output and need to be flushed at the end of decoding to get
3051 * all the decoded data. Flushing is done by calling this function with packets
3052 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3053 * returning subtitles. It is safe to flush even those decoders that are not
3054 * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
3056 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3057 * before packets may be fed to the decoder.
3059 * @param avctx the codec context
3060 * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
3061 * must be freed with avsubtitle_free if *got_sub_ptr is set.
3062 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
3063 * @param[in] avpkt The input AVPacket containing the input buffer.
3065 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
3070 * Supply raw packet data as input to a decoder.
3072 * Internally, this call will copy relevant AVCodecContext fields, which can
3073 * influence decoding per-packet, and apply them when the packet is actually
3074 * decoded. (For example AVCodecContext.skip_frame, which might direct the
3075 * decoder to drop the frame contained by the packet sent with this function.)
3077 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
3078 * larger than the actual read bytes because some optimized bitstream
3079 * readers read 32 or 64 bits at once and could read over the end.
3081 * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
3082 * on the same AVCodecContext. It will return unexpected results now
3083 * or in future libavcodec versions.
3085 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3086 * before packets may be fed to the decoder.
3088 * @param avctx codec context
3089 * @param[in] avpkt The input AVPacket. Usually, this will be a single video
3090 * frame, or several complete audio frames.
3091 * Ownership of the packet remains with the caller, and the
3092 * decoder will not write to the packet. The decoder may create
3093 * a reference to the packet data (or copy it if the packet is
3094 * not reference-counted).
3095 * Unlike with older APIs, the packet is always fully consumed,
3096 * and if it contains multiple frames (e.g. some audio codecs),
3097 * will require you to call avcodec_receive_frame() multiple
3098 * times afterwards before you can send a new packet.
3099 * It can be NULL (or an AVPacket with data set to NULL and
3100 * size set to 0); in this case, it is considered a flush
3101 * packet, which signals the end of the stream. Sending the
3102 * first flush packet will return success. Subsequent ones are
3103 * unnecessary and will return AVERROR_EOF. If the decoder
3104 * still has frames buffered, it will return them after sending
3107 * @return 0 on success, otherwise negative error code:
3108 * AVERROR(EAGAIN): input is not accepted in the current state - user
3109 * must read output with avcodec_receive_frame() (once
3110 * all output is read, the packet should be resent, and
3111 * the call will not fail with EAGAIN).
3112 * AVERROR_EOF: the decoder has been flushed, and no new packets can
3113 * be sent to it (also returned if more than 1 flush
3115 * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
3116 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
3117 * other errors: legitimate decoding errors
3119 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
3122 * Return decoded output data from a decoder.
3124 * @param avctx codec context
3125 * @param frame This will be set to a reference-counted video or audio
3126 * frame (depending on the decoder type) allocated by the
3127 * decoder. Note that the function will always call
3128 * av_frame_unref(frame) before doing anything else.
3131 * 0: success, a frame was returned
3132 * AVERROR(EAGAIN): output is not available in this state - user must try
3134 * AVERROR_EOF: the decoder has been fully flushed, and there will be
3135 * no more output frames
3136 * AVERROR(EINVAL): codec not opened, or it is an encoder
3137 * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
3138 * with respect to first decoded frame. Applicable
3139 * when flag AV_CODEC_FLAG_DROPCHANGED is set.
3140 * other negative values: legitimate decoding errors
3142 int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
3145 * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
3146 * to retrieve buffered output packets.
3148 * @param avctx codec context
3149 * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
3150 * Ownership of the frame remains with the caller, and the
3151 * encoder will not write to the frame. The encoder may create
3152 * a reference to the frame data (or copy it if the frame is
3153 * not reference-counted).
3154 * It can be NULL, in which case it is considered a flush
3155 * packet. This signals the end of the stream. If the encoder
3156 * still has packets buffered, it will return them after this
3157 * call. Once flushing mode has been entered, additional flush
3158 * packets are ignored, and sending frames will return
3162 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
3163 * can have any number of samples.
3164 * If it is not set, frame->nb_samples must be equal to
3165 * avctx->frame_size for all frames except the last.
3166 * The final frame may be smaller than avctx->frame_size.
3167 * @return 0 on success, otherwise negative error code:
3168 * AVERROR(EAGAIN): input is not accepted in the current state - user
3169 * must read output with avcodec_receive_packet() (once
3170 * all output is read, the packet should be resent, and
3171 * the call will not fail with EAGAIN).
3172 * AVERROR_EOF: the encoder has been flushed, and no new frames can
3174 * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
3175 * decoder, or requires flush
3176 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
3177 * other errors: legitimate encoding errors
3179 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
3182 * Read encoded data from the encoder.
3184 * @param avctx codec context
3185 * @param avpkt This will be set to a reference-counted packet allocated by the
3186 * encoder. Note that the function will always call
3187 * av_packet_unref(avpkt) before doing anything else.
3188 * @return 0 on success, otherwise negative error code:
3189 * AVERROR(EAGAIN): output is not available in the current state - user
3190 * must try to send input
3191 * AVERROR_EOF: the encoder has been fully flushed, and there will be
3192 * no more output packets
3193 * AVERROR(EINVAL): codec not opened, or it is a decoder
3194 * other errors: legitimate encoding errors
3196 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
3199 * Create and return a AVHWFramesContext with values adequate for hardware
3200 * decoding. This is meant to get called from the get_format callback, and is
3201 * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
3202 * This API is for decoding with certain hardware acceleration modes/APIs only.
3204 * The returned AVHWFramesContext is not initialized. The caller must do this
3205 * with av_hwframe_ctx_init().
3207 * Calling this function is not a requirement, but makes it simpler to avoid
3208 * codec or hardware API specific details when manually allocating frames.
3210 * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
3211 * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
3212 * it unnecessary to call this function or having to care about
3213 * AVHWFramesContext initialization at all.
3215 * There are a number of requirements for calling this function:
3217 * - It must be called from get_format with the same avctx parameter that was
3218 * passed to get_format. Calling it outside of get_format is not allowed, and
3219 * can trigger undefined behavior.
3220 * - The function is not always supported (see description of return values).
3221 * Even if this function returns successfully, hwaccel initialization could
3222 * fail later. (The degree to which implementations check whether the stream
3223 * is actually supported varies. Some do this check only after the user's
3224 * get_format callback returns.)
3225 * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
3226 * user decides to use a AVHWFramesContext prepared with this API function,
3227 * the user must return the same hw_pix_fmt from get_format.
3228 * - The device_ref passed to this function must support the given hw_pix_fmt.
3229 * - After calling this API function, it is the user's responsibility to
3230 * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
3231 * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
3232 * before returning from get_format (this is implied by the normal
3233 * AVCodecContext.hw_frames_ctx API rules).
3234 * - The AVHWFramesContext parameters may change every time time get_format is
3235 * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
3236 * you are inherently required to go through this process again on every
3238 * - It is perfectly possible to call this function without actually using
3239 * the resulting AVHWFramesContext. One use-case might be trying to reuse a
3240 * previously initialized AVHWFramesContext, and calling this API function
3241 * only to test whether the required frame parameters have changed.
3242 * - Fields that use dynamically allocated values of any kind must not be set
3243 * by the user unless setting them is explicitly allowed by the documentation.
3244 * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
3245 * the new free callback must call the potentially set previous free callback.
3246 * This API call may set any dynamically allocated fields, including the free
3249 * The function will set at least the following fields on AVHWFramesContext
3250 * (potentially more, depending on hwaccel API):
3252 * - All fields set by av_hwframe_ctx_alloc().
3253 * - Set the format field to hw_pix_fmt.
3254 * - Set the sw_format field to the most suited and most versatile format. (An
3255 * implication is that this will prefer generic formats over opaque formats
3256 * with arbitrary restrictions, if possible.)
3257 * - Set the width/height fields to the coded frame size, rounded up to the
3258 * API-specific minimum alignment.
3259 * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
3260 * field to the number of maximum reference surfaces possible with the codec,
3261 * plus 1 surface for the user to work (meaning the user can safely reference
3262 * at most 1 decoded surface at a time), plus additional buffering introduced
3263 * by frame threading. If the hwaccel does not require pre-allocation, the
3264 * field is left to 0, and the decoder will allocate new surfaces on demand
3266 * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
3269 * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
3270 * with basic frame parameters set.
3272 * The function is stateless, and does not change the AVCodecContext or the
3273 * device_ref AVHWDeviceContext.
3275 * @param avctx The context which is currently calling get_format, and which
3276 * implicitly contains all state needed for filling the returned
3277 * AVHWFramesContext properly.
3278 * @param device_ref A reference to the AVHWDeviceContext describing the device
3279 * which will be used by the hardware decoder.
3280 * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
3281 * @param out_frames_ref On success, set to a reference to an _uninitialized_
3282 * AVHWFramesContext, created from the given device_ref.
3283 * Fields will be set to values required for decoding.
3284 * Not changed if an error is returned.
3285 * @return zero on success, a negative value on error. The following error codes
3286 * have special semantics:
3287 * AVERROR(ENOENT): the decoder does not support this functionality. Setup
3288 * is always manual, or it is a decoder which does not
3289 * support setting AVCodecContext.hw_frames_ctx at all,
3290 * or it is a software format.
3291 * AVERROR(EINVAL): it is known that hardware decoding is not supported for
3292 * this configuration, or the device_ref is not supported
3293 * for the hwaccel referenced by hw_pix_fmt.
3295 int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
3296 AVBufferRef *device_ref,
3297 enum AVPixelFormat hw_pix_fmt,
3298 AVBufferRef **out_frames_ref);
3303 * @defgroup lavc_parsing Frame parsing
3307 enum AVPictureStructure {
3308 AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
3309 AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
3310 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
3311 AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
3314 typedef struct AVCodecParserContext {
3316 struct AVCodecParser *parser;
3317 int64_t frame_offset; /* offset of the current frame */
3318 int64_t cur_offset; /* current offset
3319 (incremented by each av_parser_parse()) */
3320 int64_t next_frame_offset; /* offset of the next frame */
3322 int pict_type; /* XXX: Put it back in AVCodecContext. */
3324 * This field is used for proper frame duration computation in lavf.
3325 * It signals, how much longer the frame duration of the current frame
3326 * is compared to normal frame duration.
3328 * frame_duration = (1 + repeat_pict) * time_base
3330 * It is used by codecs like H.264 to display telecined material.
3332 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
3333 int64_t pts; /* pts of the current frame */
3334 int64_t dts; /* dts of the current frame */
3339 int fetch_timestamp;
3341 #define AV_PARSER_PTS_NB 4
3342 int cur_frame_start_index;
3343 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
3344 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
3345 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
3348 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
3349 #define PARSER_FLAG_ONCE 0x0002
3350 /// Set if the parser has a valid file offset
3351 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
3352 #define PARSER_FLAG_USE_CODEC_TS 0x1000
3354 int64_t offset; ///< byte offset from starting packet start
3355 int64_t cur_frame_end[AV_PARSER_PTS_NB];
3358 * Set by parser to 1 for key frames and 0 for non-key frames.
3359 * It is initialized to -1, so if the parser doesn't set this flag,
3360 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
3365 // Timestamp generation support:
3367 * Synchronization point for start of timestamp generation.
3369 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
3372 * For example, this corresponds to presence of H.264 buffering period
3378 * Offset of the current timestamp against last timestamp sync point in
3379 * units of AVCodecContext.time_base.
3381 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3382 * contain a valid timestamp offset.
3384 * Note that the timestamp of sync point has usually a nonzero
3385 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
3386 * the next frame after timestamp sync point will be usually 1.
3388 * For example, this corresponds to H.264 cpb_removal_delay.
3390 int dts_ref_dts_delta;
3393 * Presentation delay of current frame in units of AVCodecContext.time_base.
3395 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3396 * contain valid non-negative timestamp delta (presentation time of a frame
3397 * must not lie in the past).
3399 * This delay represents the difference between decoding and presentation
3400 * time of the frame.
3402 * For example, this corresponds to H.264 dpb_output_delay.
3407 * Position of the packet in file.
3409 * Analogous to cur_frame_pts/dts
3411 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
3414 * Byte position of currently parsed frame in stream.
3419 * Previous frame byte position.
3424 * Duration of the current frame.
3425 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
3426 * For all other types, this is in units of AVCodecContext.time_base.
3430 enum AVFieldOrder field_order;
3433 * Indicate whether a picture is coded as a frame, top field or bottom field.
3435 * For example, H.264 field_pic_flag equal to 0 corresponds to
3436 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
3437 * equal to 1 and bottom_field_flag equal to 0 corresponds to
3438 * AV_PICTURE_STRUCTURE_TOP_FIELD.
3440 enum AVPictureStructure picture_structure;
3443 * Picture number incremented in presentation or output order.
3444 * This field may be reinitialized at the first picture of a new sequence.
3446 * For example, this corresponds to H.264 PicOrderCnt.
3448 int output_picture_number;
3451 * Dimensions of the decoded video intended for presentation.
3457 * Dimensions of the coded video.
3463 * The format of the coded data, corresponds to enum AVPixelFormat for video
3464 * and for enum AVSampleFormat for audio.
3466 * Note that a decoder can have considerable freedom in how exactly it
3467 * decodes the data, so the format reported here might be different from the
3468 * one returned by a decoder.
3471 } AVCodecParserContext;
3473 typedef struct AVCodecParser {
3474 int codec_ids[5]; /* several codec IDs are permitted */
3476 int (*parser_init)(AVCodecParserContext *s);
3477 /* This callback never returns an error, a negative value means that
3478 * the frame start was in a previous packet. */
3479 int (*parser_parse)(AVCodecParserContext *s,
3480 AVCodecContext *avctx,
3481 const uint8_t **poutbuf, int *poutbuf_size,
3482 const uint8_t *buf, int buf_size);
3483 void (*parser_close)(AVCodecParserContext *s);
3484 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
3488 * Iterate over all registered codec parsers.
3490 * @param opaque a pointer where libavcodec will store the iteration state. Must
3491 * point to NULL to start the iteration.
3493 * @return the next registered codec parser or NULL when the iteration is
3496 const AVCodecParser *av_parser_iterate(void **opaque);
3498 AVCodecParserContext *av_parser_init(int codec_id);
3503 * @param s parser context.
3504 * @param avctx codec context.
3505 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
3506 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
3507 * @param buf input buffer.
3508 * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
3509 size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
3510 To signal EOF, this should be 0 (so that the last frame
3512 * @param pts input presentation timestamp.
3513 * @param dts input decoding timestamp.
3514 * @param pos input byte position in stream.
3515 * @return the number of bytes of the input bitstream used.
3520 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
3527 * decode_frame(data, size);
3531 int av_parser_parse2(AVCodecParserContext *s,
3532 AVCodecContext *avctx,
3533 uint8_t **poutbuf, int *poutbuf_size,
3534 const uint8_t *buf, int buf_size,
3535 int64_t pts, int64_t dts,
3538 #if FF_API_PARSER_CHANGE
3540 * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
3541 * @deprecated Use dump_extradata, remove_extra or extract_extradata
3542 * bitstream filters instead.
3544 attribute_deprecated
3545 int av_parser_change(AVCodecParserContext *s,
3546 AVCodecContext *avctx,
3547 uint8_t **poutbuf, int *poutbuf_size,
3548 const uint8_t *buf, int buf_size, int keyframe);
3550 void av_parser_close(AVCodecParserContext *s);
3558 * @addtogroup lavc_encoding
3562 #if FF_API_OLD_ENCDEC
3564 * Encode a frame of audio.
3566 * Takes input samples from frame and writes the next output packet, if
3567 * available, to avpkt. The output packet does not necessarily contain data for
3568 * the most recent frame, as encoders can delay, split, and combine input frames
3569 * internally as needed.
3571 * @param avctx codec context
3572 * @param avpkt output AVPacket.
3573 * The user can supply an output buffer by setting
3574 * avpkt->data and avpkt->size prior to calling the
3575 * function, but if the size of the user-provided data is not
3576 * large enough, encoding will fail. If avpkt->data and
3577 * avpkt->size are set, avpkt->destruct must also be set. All
3578 * other AVPacket fields will be reset by the encoder using
3579 * av_init_packet(). If avpkt->data is NULL, the encoder will
3580 * allocate it. The encoder will set avpkt->size to the size
3581 * of the output packet.
3583 * If this function fails or produces no output, avpkt will be
3584 * freed using av_packet_unref().
3585 * @param[in] frame AVFrame containing the raw audio data to be encoded.
3586 * May be NULL when flushing an encoder that has the
3587 * AV_CODEC_CAP_DELAY capability set.
3588 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
3589 * can have any number of samples.
3590 * If it is not set, frame->nb_samples must be equal to
3591 * avctx->frame_size for all frames except the last.
3592 * The final frame may be smaller than avctx->frame_size.
3593 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
3594 * output packet is non-empty, and to 0 if it is
3595 * empty. If the function returns an error, the
3596 * packet can be assumed to be invalid, and the
3597 * value of got_packet_ptr is undefined and should
3599 * @return 0 on success, negative error code on failure
3601 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead.
3602 * If allowed and required, set AVCodecContext.get_encode_buffer to
3603 * a custom function to pass user supplied output buffers.
3605 attribute_deprecated
3606 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
3607 const AVFrame *frame, int *got_packet_ptr);
3610 * Encode a frame of video.
3612 * Takes input raw video data from frame and writes the next output packet, if
3613 * available, to avpkt. The output packet does not necessarily contain data for
3614 * the most recent frame, as encoders can delay and reorder input frames
3615 * internally as needed.
3617 * @param avctx codec context
3618 * @param avpkt output AVPacket.
3619 * The user can supply an output buffer by setting
3620 * avpkt->data and avpkt->size prior to calling the
3621 * function, but if the size of the user-provided data is not
3622 * large enough, encoding will fail. All other AVPacket fields
3623 * will be reset by the encoder using av_init_packet(). If
3624 * avpkt->data is NULL, the encoder will allocate it.
3625 * The encoder will set avpkt->size to the size of the
3626 * output packet. The returned data (if any) belongs to the
3627 * caller, he is responsible for freeing it.
3629 * If this function fails or produces no output, avpkt will be
3630 * freed using av_packet_unref().
3631 * @param[in] frame AVFrame containing the raw video data to be encoded.
3632 * May be NULL when flushing an encoder that has the
3633 * AV_CODEC_CAP_DELAY capability set.
3634 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
3635 * output packet is non-empty, and to 0 if it is
3636 * empty. If the function returns an error, the
3637 * packet can be assumed to be invalid, and the
3638 * value of got_packet_ptr is undefined and should
3640 * @return 0 on success, negative error code on failure
3642 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead.
3643 * If allowed and required, set AVCodecContext.get_encode_buffer to
3644 * a custom function to pass user supplied output buffers.
3646 attribute_deprecated
3647 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
3648 const AVFrame *frame, int *got_packet_ptr);
3651 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3652 const AVSubtitle *sub);
3659 #if FF_API_AVPICTURE
3661 * @addtogroup lavc_picture
3666 * @deprecated unused
3668 attribute_deprecated
3669 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
3672 * @deprecated unused
3674 attribute_deprecated
3675 void avpicture_free(AVPicture *picture);
3678 * @deprecated use av_image_fill_arrays() instead.
3680 attribute_deprecated
3681 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
3682 enum AVPixelFormat pix_fmt, int width, int height);
3685 * @deprecated use av_image_copy_to_buffer() instead.
3687 attribute_deprecated
3688 int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
3689 int width, int height,
3690 unsigned char *dest, int dest_size);
3693 * @deprecated use av_image_get_buffer_size() instead.
3695 attribute_deprecated
3696 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
3699 * @deprecated av_image_copy() instead.
3701 attribute_deprecated
3702 void av_picture_copy(AVPicture *dst, const AVPicture *src,
3703 enum AVPixelFormat pix_fmt, int width, int height);
3706 * @deprecated unused
3708 attribute_deprecated
3709 int av_picture_crop(AVPicture *dst, const AVPicture *src,
3710 enum AVPixelFormat pix_fmt, int top_band, int left_band);
3713 * @deprecated unused
3715 attribute_deprecated
3716 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
3717 int padtop, int padbottom, int padleft, int padright, int *color);
3725 * @defgroup lavc_misc Utility functions
3728 * Miscellaneous utility functions related to both encoding and decoding
3734 * @defgroup lavc_misc_pixfmt Pixel formats
3736 * Functions for working with pixel formats.
3740 #if FF_API_GETCHROMA
3742 * @deprecated Use av_pix_fmt_get_chroma_sub_sample
3745 attribute_deprecated
3746 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
3750 * Return a value representing the fourCC code associated to the
3751 * pixel format pix_fmt, or 0 if no associated fourCC code can be
3754 unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
3757 * Find the best pixel format to convert to given a certain source pixel
3758 * format. When converting from one pixel format to another, information loss
3759 * may occur. For example, when converting from RGB24 to GRAY, the color
3760 * information will be lost. Similarly, other losses occur when converting from
3761 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
3762 * the given pixel formats should be used to suffer the least amount of loss.
3763 * The pixel formats from which it chooses one, are determined by the
3764 * pix_fmt_list parameter.
3767 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
3768 * @param[in] src_pix_fmt source pixel format
3769 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
3770 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
3771 * @return The best pixel format to convert to or -1 if none was found.
3773 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
3774 enum AVPixelFormat src_pix_fmt,
3775 int has_alpha, int *loss_ptr);
3777 #if FF_API_AVCODEC_PIX_FMT
3779 * @deprecated see av_get_pix_fmt_loss()
3781 attribute_deprecated
3782 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
3785 * @deprecated see av_find_best_pix_fmt_of_2()
3787 attribute_deprecated
3788 enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
3789 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
3791 attribute_deprecated
3792 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
3793 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
3796 enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
3802 #if FF_API_TAG_STRING
3804 * Put a string representing the codec tag codec_tag in buf.
3806 * @param buf buffer to place codec tag in
3807 * @param buf_size size in bytes of buf
3808 * @param codec_tag codec tag to assign
3809 * @return the length of the string that would have been generated if
3810 * enough space had been available, excluding the trailing null
3812 * @deprecated see av_fourcc_make_string() and av_fourcc2str().
3814 attribute_deprecated
3815 size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
3818 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
3821 * Return a name for the specified profile, if available.
3823 * @param codec the codec that is searched for the given profile
3824 * @param profile the profile value for which a name is requested
3825 * @return A name for the profile if found, NULL otherwise.
3827 const char *av_get_profile_name(const AVCodec *codec, int profile);
3830 * Return a name for the specified profile, if available.
3832 * @param codec_id the ID of the codec to which the requested profile belongs
3833 * @param profile the profile value for which a name is requested
3834 * @return A name for the profile if found, NULL otherwise.
3836 * @note unlike av_get_profile_name(), which searches a list of profiles
3837 * supported by a specific decoder or encoder implementation, this
3838 * function searches the list of profiles from the AVCodecDescriptor
3840 const char *avcodec_profile_name(enum AVCodecID codec_id, int profile);
3842 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
3843 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
3844 //FIXME func typedef
3847 * Fill AVFrame audio data and linesize pointers.
3849 * The buffer buf must be a preallocated buffer with a size big enough
3850 * to contain the specified samples amount. The filled AVFrame data
3851 * pointers will point to this buffer.
3853 * AVFrame extended_data channel pointers are allocated if necessary for
3856 * @param frame the AVFrame
3857 * frame->nb_samples must be set prior to calling the
3858 * function. This function fills in frame->data,
3859 * frame->extended_data, frame->linesize[0].
3860 * @param nb_channels channel count
3861 * @param sample_fmt sample format
3862 * @param buf buffer to use for frame data
3863 * @param buf_size size of buffer
3864 * @param align plane size sample alignment (0 = default)
3865 * @return >=0 on success, negative error code on failure
3866 * @todo return the size in bytes required to store the samples in
3867 * case of success, at the next libavutil bump
3869 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
3870 enum AVSampleFormat sample_fmt, const uint8_t *buf,
3871 int buf_size, int align);
3874 * Reset the internal codec state / flush internal buffers. Should be called
3875 * e.g. when seeking or when switching to a different stream.
3877 * @note for decoders, when refcounted frames are not used
3878 * (i.e. avctx->refcounted_frames is 0), this invalidates the frames previously
3879 * returned from the decoder. When refcounted frames are used, the decoder just
3880 * releases any references it might keep internally, but the caller's reference
3883 * @note for encoders, this function will only do something if the encoder
3884 * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3885 * will drain any remaining packets, and can then be re-used for a different
3886 * stream (as opposed to sending a null frame which will leave the encoder
3887 * in a permanent EOF state after draining). This can be desirable if the
3888 * cost of tearing down and replacing the encoder instance is high.
3890 void avcodec_flush_buffers(AVCodecContext *avctx);
3893 * Return codec bits per sample.
3895 * @param[in] codec_id the codec
3896 * @return Number of bits per sample or zero if unknown for the given codec.
3898 int av_get_bits_per_sample(enum AVCodecID codec_id);
3901 * Return the PCM codec associated with a sample format.
3902 * @param be endianness, 0 for little, 1 for big,
3903 * -1 (or anything else) for native
3904 * @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
3906 enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
3909 * Return codec bits per sample.
3910 * Only return non-zero if the bits per sample is exactly correct, not an
3913 * @param[in] codec_id the codec
3914 * @return Number of bits per sample or zero if unknown for the given codec.
3916 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
3919 * Return audio frame duration.
3921 * @param avctx codec context
3922 * @param frame_bytes size of the frame, or 0 if unknown
3923 * @return frame duration, in samples, if known. 0 if not able to
3926 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
3929 * This function is the same as av_get_audio_frame_duration(), except it works
3930 * with AVCodecParameters instead of an AVCodecContext.
3932 int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
3937 * Same behaviour av_fast_malloc but the buffer has additional
3938 * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
3940 * In addition the whole buffer will initially and after resizes
3941 * be 0-initialized so that no uninitialized data will ever appear.
3943 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
3946 * Same behaviour av_fast_padded_malloc except that buffer will always
3947 * be 0-initialized after call.
3949 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
3952 * Encode extradata length to a buffer. Used by xiph codecs.
3954 * @param s buffer to write to; must be at least (v/255+1) bytes long
3955 * @param v size of extradata in bytes
3956 * @return number of bytes written to the buffer.
3958 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
3960 #if FF_API_USER_VISIBLE_AVHWACCEL
3962 * Register the hardware accelerator hwaccel.
3964 * @deprecated This function doesn't do anything.
3966 attribute_deprecated
3967 void av_register_hwaccel(AVHWAccel *hwaccel);
3970 * If hwaccel is NULL, returns the first registered hardware accelerator,
3971 * if hwaccel is non-NULL, returns the next registered hardware accelerator
3972 * after hwaccel, or NULL if hwaccel is the last one.
3974 * @deprecated AVHWaccel structures contain no user-serviceable parts, so
3975 * this function should not be used.
3977 attribute_deprecated
3978 AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel);
3983 * Lock operation used by lockmgr
3985 * @deprecated Deprecated together with av_lockmgr_register().
3988 AV_LOCK_CREATE, ///< Create a mutex
3989 AV_LOCK_OBTAIN, ///< Lock the mutex
3990 AV_LOCK_RELEASE, ///< Unlock the mutex
3991 AV_LOCK_DESTROY, ///< Free mutex resources
3995 * Register a user provided lock manager supporting the operations
3996 * specified by AVLockOp. The "mutex" argument to the function points
3997 * to a (void *) where the lockmgr should store/get a pointer to a user
3998 * allocated mutex. It is NULL upon AV_LOCK_CREATE and equal to the
3999 * value left by the last call for all other ops. If the lock manager is
4000 * unable to perform the op then it should leave the mutex in the same
4001 * state as when it was called and return a non-zero value. However,
4002 * when called with AV_LOCK_DESTROY the mutex will always be assumed to
4003 * have been successfully destroyed. If av_lockmgr_register succeeds
4004 * it will return a non-negative value, if it fails it will return a
4005 * negative value and destroy all mutex and unregister all callbacks.
4006 * av_lockmgr_register is not thread-safe, it must be called from a
4007 * single thread before any calls which make use of locking are used.
4009 * @param cb User defined callback. av_lockmgr_register invokes calls
4010 * to this callback and the previously registered callback.
4011 * The callback will be used to create more than one mutex
4012 * each of which must be backed by its own underlying locking
4013 * mechanism (i.e. do not use a single static object to
4014 * implement your lock manager). If cb is set to NULL the
4015 * lockmgr will be unregistered.
4017 * @deprecated This function does nothing, and always returns 0. Be sure to
4018 * build with thread support to get basic thread safety.
4020 attribute_deprecated
4021 int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
4025 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
4026 * with no corresponding avcodec_close()), 0 otherwise.
4028 int avcodec_is_open(AVCodecContext *s);
4031 * Allocate a CPB properties structure and initialize its fields to default
4034 * @param size if non-NULL, the size of the allocated struct will be written
4035 * here. This is useful for embedding it in side data.
4037 * @return the newly allocated struct or NULL on failure
4039 AVCPBProperties *av_cpb_properties_alloc(size_t *size);
4045 #endif /* AVCODEC_AVCODEC_H */