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;
808 * qscale offset between IP and B-frames
809 * - encoding: Set by user.
812 float b_quant_offset;
815 * Size of the frame reordering buffer in the decoder.
816 * For MPEG-2 it is 1 IPB or 0 low delay IP.
817 * - encoding: Set by libavcodec.
818 * - decoding: Set by libavcodec.
823 * qscale factor between P- and I-frames
824 * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
825 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
826 * - encoding: Set by user.
829 float i_quant_factor;
832 * qscale offset between P and I-frames
833 * - encoding: Set by user.
836 float i_quant_offset;
839 * luminance masking (0-> disabled)
840 * - encoding: Set by user.
846 * temporary complexity masking (0-> disabled)
847 * - encoding: Set by user.
850 float temporal_cplx_masking;
853 * spatial complexity masking (0-> disabled)
854 * - encoding: Set by user.
857 float spatial_cplx_masking;
860 * p block masking (0-> disabled)
861 * - encoding: Set by user.
867 * darkness masking (0-> disabled)
868 * - encoding: Set by user.
875 * - encoding: Set by libavcodec.
876 * - decoding: Set by user (or 0).
881 * slice offsets in the frame in bytes
882 * - encoding: Set/allocated by libavcodec.
883 * - decoding: Set/allocated by user (or NULL).
888 * sample aspect ratio (0 if unknown)
889 * That is the width of a pixel divided by the height of the pixel.
890 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
891 * - encoding: Set by user.
892 * - decoding: Set by libavcodec.
894 AVRational sample_aspect_ratio;
897 * motion estimation comparison function
898 * - encoding: Set by user.
903 * subpixel motion estimation comparison function
904 * - encoding: Set by user.
909 * macroblock comparison function (not supported yet)
910 * - encoding: Set by user.
915 * interlaced DCT comparison function
916 * - encoding: Set by user.
922 #define FF_CMP_SATD 2
924 #define FF_CMP_PSNR 4
927 #define FF_CMP_ZERO 7
928 #define FF_CMP_VSAD 8
929 #define FF_CMP_VSSE 9
930 #define FF_CMP_NSSE 10
931 #define FF_CMP_W53 11
932 #define FF_CMP_W97 12
933 #define FF_CMP_DCTMAX 13
934 #define FF_CMP_DCT264 14
935 #define FF_CMP_MEDIAN_SAD 15
936 #define FF_CMP_CHROMA 256
939 * ME diamond size & shape
940 * - encoding: Set by user.
946 * amount of previous MV predictors (2a+1 x 2a+1 square)
947 * - encoding: Set by user.
950 int last_predictor_count;
953 * motion estimation prepass comparison function
954 * - encoding: Set by user.
960 * ME prepass diamond size & shape
961 * - encoding: Set by user.
968 * - encoding: Set by user.
971 int me_subpel_quality;
974 * maximum motion estimation search range in subpel units
975 * If 0 then no limit.
977 * - encoding: Set by user.
985 * - decoding: Set by user.
988 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
989 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
990 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
993 * macroblock decision mode
994 * - encoding: Set by user.
998 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
999 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1000 #define FF_MB_DECISION_RD 2 ///< rate distortion
1003 * custom intra quantization matrix
1004 * Must be allocated with the av_malloc() family of functions, and will be freed in
1005 * avcodec_free_context().
1006 * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
1007 * - decoding: Set/allocated/freed by libavcodec.
1009 uint16_t *intra_matrix;
1012 * custom inter quantization matrix
1013 * Must be allocated with the av_malloc() family of functions, and will be freed in
1014 * avcodec_free_context().
1015 * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
1016 * - decoding: Set/allocated/freed by libavcodec.
1018 uint16_t *inter_matrix;
1021 * precision of the intra DC coefficient - 8
1022 * - encoding: Set by user.
1023 * - decoding: Set by libavcodec
1025 int intra_dc_precision;
1028 * Number of macroblock rows at the top which are skipped.
1029 * - encoding: unused
1030 * - decoding: Set by user.
1035 * Number of macroblock rows at the bottom which are skipped.
1036 * - encoding: unused
1037 * - decoding: Set by user.
1042 * minimum MB Lagrange multiplier
1043 * - encoding: Set by user.
1044 * - decoding: unused
1049 * maximum MB Lagrange multiplier
1050 * - encoding: Set by user.
1051 * - decoding: unused
1056 * - encoding: Set by user.
1057 * - decoding: unused
1063 * - encoding: Set by user.
1064 * - decoding: unused
1069 * number of reference frames
1070 * - encoding: Set by user.
1071 * - decoding: Set by lavc.
1076 * Note: Value depends upon the compare function used for fullpel ME.
1077 * - encoding: Set by user.
1078 * - decoding: unused
1083 * Chromaticity coordinates of the source primaries.
1084 * - encoding: Set by user
1085 * - decoding: Set by libavcodec
1087 enum AVColorPrimaries color_primaries;
1090 * Color Transfer Characteristic.
1091 * - encoding: Set by user
1092 * - decoding: Set by libavcodec
1094 enum AVColorTransferCharacteristic color_trc;
1097 * YUV colorspace type.
1098 * - encoding: Set by user
1099 * - decoding: Set by libavcodec
1101 enum AVColorSpace colorspace;
1104 * MPEG vs JPEG YUV range.
1105 * - encoding: Set by user
1106 * - decoding: Set by libavcodec
1108 enum AVColorRange color_range;
1111 * This defines the location of chroma samples.
1112 * - encoding: Set by user
1113 * - decoding: Set by libavcodec
1115 enum AVChromaLocation chroma_sample_location;
1119 * Indicates number of picture subdivisions. Used for parallelized
1121 * - encoding: Set by user
1122 * - decoding: unused
1127 * - encoding: set by libavcodec
1128 * - decoding: Set by user.
1130 enum AVFieldOrder field_order;
1133 int sample_rate; ///< samples per second
1134 int channels; ///< number of audio channels
1137 * audio sample format
1138 * - encoding: Set by user.
1139 * - decoding: Set by libavcodec.
1141 enum AVSampleFormat sample_fmt; ///< sample format
1143 /* The following data should not be initialized. */
1145 * Number of samples per channel in an audio frame.
1147 * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1148 * except the last must contain exactly frame_size samples per channel.
1149 * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1150 * frame size is not restricted.
1151 * - decoding: may be set by some decoders to indicate constant frame size
1156 * Frame counter, set by libavcodec.
1158 * - decoding: total number of frames returned from the decoder so far.
1159 * - encoding: total number of frames passed to the encoder so far.
1161 * @note the counter is not incremented if encoding/decoding resulted in
1167 * number of bytes per packet if constant and known or 0
1168 * Used by some WAV based audio codecs.
1173 * Audio cutoff bandwidth (0 means "automatic")
1174 * - encoding: Set by user.
1175 * - decoding: unused
1180 * Audio channel layout.
1181 * - encoding: set by user.
1182 * - decoding: set by user, may be overwritten by libavcodec.
1184 uint64_t channel_layout;
1187 * Request decoder to use this channel layout if it can (0 for default)
1188 * - encoding: unused
1189 * - decoding: Set by user.
1191 uint64_t request_channel_layout;
1194 * Type of service that the audio stream conveys.
1195 * - encoding: Set by user.
1196 * - decoding: Set by libavcodec.
1198 enum AVAudioServiceType audio_service_type;
1201 * desired sample format
1202 * - encoding: Not used.
1203 * - decoding: Set by user.
1204 * Decoder will decode to this format if it can.
1206 enum AVSampleFormat request_sample_fmt;
1209 * This callback is called at the beginning of each frame to get data
1210 * buffer(s) for it. There may be one contiguous buffer for all the data or
1211 * there may be a buffer per each data plane or anything in between. What
1212 * this means is, you may set however many entries in buf[] you feel necessary.
1213 * Each buffer must be reference-counted using the AVBuffer API (see description
1216 * The following fields will be set in the frame before this callback is
1219 * - width, height (video only)
1220 * - sample_rate, channel_layout, nb_samples (audio only)
1221 * Their values may differ from the corresponding values in
1222 * AVCodecContext. This callback must use the frame values, not the codec
1223 * context values, to calculate the required buffer size.
1225 * This callback must fill the following fields in the frame:
1229 * * if the data is planar audio with more than 8 channels, then this
1230 * callback must allocate and fill extended_data to contain all pointers
1231 * to all data planes. data[] must hold as many pointers as it can.
1232 * extended_data must be allocated with av_malloc() and will be freed in
1234 * * otherwise extended_data must point to data
1235 * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1236 * the frame's data and extended_data pointers must be contained in these. That
1237 * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1238 * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1239 * and av_buffer_ref().
1240 * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1241 * this callback and filled with the extra buffers if there are more
1242 * buffers than buf[] can hold. extended_buf will be freed in
1245 * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1246 * avcodec_default_get_buffer2() instead of providing buffers allocated by
1249 * Each data plane must be aligned to the maximum required by the target
1252 * @see avcodec_default_get_buffer2()
1256 * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1257 * (read and/or written to if it is writable) later by libavcodec.
1259 * avcodec_align_dimensions2() should be used to find the required width and
1260 * height, as they normally need to be rounded up to the next multiple of 16.
1262 * Some decoders do not support linesizes changing between frames.
1264 * If frame multithreading is used, this callback may be called from a
1265 * different thread, but not from more than one at once. Does not need to be
1268 * @see avcodec_align_dimensions2()
1272 * Decoders request a buffer of a particular size by setting
1273 * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1274 * however, utilize only part of the buffer by setting AVFrame.nb_samples
1275 * to a smaller value in the output frame.
1277 * As a convenience, av_samples_get_buffer_size() and
1278 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1279 * functions to find the required data size and to fill data pointers and
1280 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1281 * since all planes must be the same size.
1283 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1285 * - encoding: unused
1286 * - decoding: Set by libavcodec, user can override.
1288 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
1290 #if FF_API_OLD_ENCDEC
1292 * If non-zero, the decoded audio and video frames returned from
1293 * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
1294 * and are valid indefinitely. The caller must free them with
1295 * av_frame_unref() when they are not needed anymore.
1296 * Otherwise, the decoded frames must not be freed by the caller and are
1297 * only valid until the next decode call.
1299 * This is always automatically enabled if avcodec_receive_frame() is used.
1301 * - encoding: unused
1302 * - decoding: set by the caller before avcodec_open2().
1304 attribute_deprecated
1305 int refcounted_frames;
1308 /* - encoding parameters */
1309 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1310 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1314 * - encoding: Set by user.
1315 * - decoding: unused
1321 * - encoding: Set by user.
1322 * - decoding: unused
1327 * maximum quantizer difference between frames
1328 * - encoding: Set by user.
1329 * - decoding: unused
1334 * decoder bitstream buffer size
1335 * - encoding: Set by user.
1336 * - decoding: unused
1341 * ratecontrol override, see RcOverride
1342 * - encoding: Allocated/set/freed by user.
1343 * - decoding: unused
1345 int rc_override_count;
1346 RcOverride *rc_override;
1350 * - encoding: Set by user.
1351 * - decoding: Set by user, may be overwritten by libavcodec.
1353 int64_t rc_max_rate;
1357 * - encoding: Set by user.
1358 * - decoding: unused
1360 int64_t rc_min_rate;
1363 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1364 * - encoding: Set by user.
1365 * - decoding: unused.
1367 float rc_max_available_vbv_use;
1370 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1371 * - encoding: Set by user.
1372 * - decoding: unused.
1374 float rc_min_vbv_overflow_use;
1377 * Number of bits which should be loaded into the rc buffer before decoding starts.
1378 * - encoding: Set by user.
1379 * - decoding: unused
1381 int rc_initial_buffer_occupancy;
1384 * trellis RD quantization
1385 * - encoding: Set by user.
1386 * - decoding: unused
1390 #if FF_API_RTP_CALLBACK
1392 * @deprecated unused
1394 /* The RTP callback: This function is called */
1395 /* every time the encoder has a packet to send. */
1396 /* It depends on the encoder if the data starts */
1397 /* with a Start Code (it should). H.263 does. */
1398 /* mb_nb contains the number of macroblocks */
1399 /* encoded in the RTP payload. */
1400 attribute_deprecated
1401 void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
1405 * pass1 encoding statistics output buffer
1406 * - encoding: Set by libavcodec.
1407 * - decoding: unused
1412 * pass2 encoding statistics input buffer
1413 * Concatenated stuff from stats_out of pass1 should be placed here.
1414 * - encoding: Allocated/set/freed by user.
1415 * - decoding: unused
1420 * Work around bugs in encoders which sometimes cannot be detected automatically.
1421 * - encoding: Set by user
1422 * - decoding: Set by user
1424 int workaround_bugs;
1425 #define FF_BUG_AUTODETECT 1 ///< autodetection
1426 #define FF_BUG_XVID_ILACE 4
1427 #define FF_BUG_UMP4 8
1428 #define FF_BUG_NO_PADDING 16
1429 #define FF_BUG_AMV 32
1430 #define FF_BUG_QPEL_CHROMA 64
1431 #define FF_BUG_STD_QPEL 128
1432 #define FF_BUG_QPEL_CHROMA2 256
1433 #define FF_BUG_DIRECT_BLOCKSIZE 512
1434 #define FF_BUG_EDGE 1024
1435 #define FF_BUG_HPEL_CHROMA 2048
1436 #define FF_BUG_DC_CLIP 4096
1437 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1438 #define FF_BUG_TRUNCATED 16384
1439 #define FF_BUG_IEDGE 32768
1442 * strictly follow the standard (MPEG-4, ...).
1443 * - encoding: Set by user.
1444 * - decoding: Set by user.
1445 * Setting this to STRICT or higher means the encoder and decoder will
1446 * generally do stupid things, whereas setting it to unofficial or lower
1447 * will mean the encoder might produce output that is not supported by all
1448 * spec-compliant decoders. Decoders don't differentiate between normal,
1449 * unofficial and experimental (that is, they always try to decode things
1450 * when they can) unless they are explicitly asked to behave stupidly
1451 * (=strictly conform to the specs)
1453 int strict_std_compliance;
1454 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
1455 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
1456 #define FF_COMPLIANCE_NORMAL 0
1457 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
1458 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
1461 * error concealment flags
1462 * - encoding: unused
1463 * - decoding: Set by user.
1465 int error_concealment;
1466 #define FF_EC_GUESS_MVS 1
1467 #define FF_EC_DEBLOCK 2
1468 #define FF_EC_FAVOR_INTER 256
1472 * - encoding: Set by user.
1473 * - decoding: Set by user.
1476 #define FF_DEBUG_PICT_INFO 1
1477 #define FF_DEBUG_RC 2
1478 #define FF_DEBUG_BITSTREAM 4
1479 #define FF_DEBUG_MB_TYPE 8
1480 #define FF_DEBUG_QP 16
1481 #define FF_DEBUG_DCT_COEFF 0x00000040
1482 #define FF_DEBUG_SKIP 0x00000080
1483 #define FF_DEBUG_STARTCODE 0x00000100
1484 #define FF_DEBUG_ER 0x00000400
1485 #define FF_DEBUG_MMCO 0x00000800
1486 #define FF_DEBUG_BUGS 0x00001000
1487 #define FF_DEBUG_BUFFERS 0x00008000
1488 #define FF_DEBUG_THREADS 0x00010000
1489 #define FF_DEBUG_GREEN_MD 0x00800000
1490 #define FF_DEBUG_NOMC 0x01000000
1493 * Error recognition; may misdetect some more or less valid parts as errors.
1494 * - encoding: Set by user.
1495 * - decoding: Set by user.
1497 int err_recognition;
1500 * Verify checksums embedded in the bitstream (could be of either encoded or
1501 * decoded data, depending on the codec) and print an error message on mismatch.
1502 * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
1503 * decoder returning an error.
1505 #define AV_EF_CRCCHECK (1<<0)
1506 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
1507 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
1508 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
1510 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
1511 #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
1512 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
1513 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
1517 * opaque 64-bit number (generally a PTS) that will be reordered and
1518 * output in AVFrame.reordered_opaque
1519 * - encoding: Set by libavcodec to the reordered_opaque of the input
1520 * frame corresponding to the last returned packet. Only
1521 * supported by encoders with the
1522 * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1523 * - decoding: Set by user.
1525 int64_t reordered_opaque;
1528 * Hardware accelerator in use
1529 * - encoding: unused.
1530 * - decoding: Set by libavcodec
1532 const struct AVHWAccel *hwaccel;
1535 * Hardware accelerator context.
1536 * For some hardware accelerators, a global context needs to be
1537 * provided by the user. In that case, this holds display-dependent
1538 * data FFmpeg cannot instantiate itself. Please refer to the
1539 * FFmpeg HW accelerator documentation to know how to fill this
1540 * is. e.g. for VA API, this is a struct vaapi_context.
1541 * - encoding: unused
1542 * - decoding: Set by user
1544 void *hwaccel_context;
1548 * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1549 * - decoding: unused
1551 uint64_t error[AV_NUM_DATA_POINTERS];
1554 * DCT algorithm, see FF_DCT_* below
1555 * - encoding: Set by user.
1556 * - decoding: unused
1559 #define FF_DCT_AUTO 0
1560 #define FF_DCT_FASTINT 1
1561 #define FF_DCT_INT 2
1562 #define FF_DCT_MMX 3
1563 #define FF_DCT_ALTIVEC 5
1564 #define FF_DCT_FAAN 6
1567 * IDCT algorithm, see FF_IDCT_* below.
1568 * - encoding: Set by user.
1569 * - decoding: Set by user.
1572 #define FF_IDCT_AUTO 0
1573 #define FF_IDCT_INT 1
1574 #define FF_IDCT_SIMPLE 2
1575 #define FF_IDCT_SIMPLEMMX 3
1576 #define FF_IDCT_ARM 7
1577 #define FF_IDCT_ALTIVEC 8
1578 #define FF_IDCT_SIMPLEARM 10
1579 #define FF_IDCT_XVID 14
1580 #define FF_IDCT_SIMPLEARMV5TE 16
1581 #define FF_IDCT_SIMPLEARMV6 17
1582 #define FF_IDCT_FAAN 20
1583 #define FF_IDCT_SIMPLENEON 22
1584 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
1585 #define FF_IDCT_SIMPLEAUTO 128
1588 * bits per sample/pixel from the demuxer (needed for huffyuv).
1589 * - encoding: Set by libavcodec.
1590 * - decoding: Set by user.
1592 int bits_per_coded_sample;
1595 * Bits per sample/pixel of internal libavcodec pixel/sample format.
1596 * - encoding: set by user.
1597 * - decoding: set by libavcodec.
1599 int bits_per_raw_sample;
1602 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1603 * - encoding: unused
1604 * - decoding: Set by user.
1608 #if FF_API_CODED_FRAME
1610 * the picture in the bitstream
1611 * - encoding: Set by libavcodec.
1612 * - decoding: unused
1614 * @deprecated use the quality factor packet side data instead
1616 attribute_deprecated AVFrame *coded_frame;
1621 * is used to decide how many independent tasks should be passed to execute()
1622 * - encoding: Set by user.
1623 * - decoding: Set by user.
1628 * Which multithreading methods to use.
1629 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1630 * so clients which cannot provide future frames should not use it.
1632 * - encoding: Set by user, otherwise the default is used.
1633 * - decoding: Set by user, otherwise the default is used.
1636 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1637 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1640 * Which multithreading methods are in use by the codec.
1641 * - encoding: Set by libavcodec.
1642 * - decoding: Set by libavcodec.
1644 int active_thread_type;
1646 #if FF_API_THREAD_SAFE_CALLBACKS
1648 * Set by the client if its custom get_buffer() callback can be called
1649 * synchronously from another thread, which allows faster multithreaded decoding.
1650 * draw_horiz_band() will be called from other threads regardless of this setting.
1651 * Ignored if the default get_buffer() is used.
1652 * - encoding: Set by user.
1653 * - decoding: Set by user.
1655 * @deprecated the custom get_buffer2() callback should always be
1656 * thread-safe. Thread-unsafe get_buffer2() implementations will be
1657 * invalid starting with LIBAVCODEC_VERSION_MAJOR=60; in other words,
1658 * libavcodec will behave as if this field was always set to 1.
1659 * Callers that want to be forward compatible with future libavcodec
1660 * versions should wrap access to this field in
1661 * #if LIBAVCODEC_VERSION_MAJOR < 60
1663 attribute_deprecated
1664 int thread_safe_callbacks;
1668 * The codec may call this to execute several independent things.
1669 * It will return only after finishing all tasks.
1670 * The user may replace this with some multithreaded implementation,
1671 * the default implementation will execute the parts serially.
1672 * @param count the number of things to execute
1673 * - encoding: Set by libavcodec, user can override.
1674 * - decoding: Set by libavcodec, user can override.
1676 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1679 * The codec may call this to execute several independent things.
1680 * It will return only after finishing all tasks.
1681 * The user may replace this with some multithreaded implementation,
1682 * the default implementation will execute the parts serially.
1683 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
1684 * @param c context passed also to func
1685 * @param count the number of things to execute
1686 * @param arg2 argument passed unchanged to func
1687 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1688 * @param func function that will be called count times, with jobnr from 0 to count-1.
1689 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1690 * two instances of func executing at the same time will have the same threadnr.
1691 * @return always 0 currently, but code should handle a future improvement where when any call to func
1692 * returns < 0 no further calls to func may be done and < 0 is returned.
1693 * - encoding: Set by libavcodec, user can override.
1694 * - decoding: Set by libavcodec, user can override.
1696 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1699 * noise vs. sse weight for the nsse comparison function
1700 * - encoding: Set by user.
1701 * - decoding: unused
1707 * - encoding: Set by user.
1708 * - decoding: Set by libavcodec.
1711 #define FF_PROFILE_UNKNOWN -99
1712 #define FF_PROFILE_RESERVED -100
1714 #define FF_PROFILE_AAC_MAIN 0
1715 #define FF_PROFILE_AAC_LOW 1
1716 #define FF_PROFILE_AAC_SSR 2
1717 #define FF_PROFILE_AAC_LTP 3
1718 #define FF_PROFILE_AAC_HE 4
1719 #define FF_PROFILE_AAC_HE_V2 28
1720 #define FF_PROFILE_AAC_LD 22
1721 #define FF_PROFILE_AAC_ELD 38
1722 #define FF_PROFILE_MPEG2_AAC_LOW 128
1723 #define FF_PROFILE_MPEG2_AAC_HE 131
1725 #define FF_PROFILE_DNXHD 0
1726 #define FF_PROFILE_DNXHR_LB 1
1727 #define FF_PROFILE_DNXHR_SQ 2
1728 #define FF_PROFILE_DNXHR_HQ 3
1729 #define FF_PROFILE_DNXHR_HQX 4
1730 #define FF_PROFILE_DNXHR_444 5
1732 #define FF_PROFILE_DTS 20
1733 #define FF_PROFILE_DTS_ES 30
1734 #define FF_PROFILE_DTS_96_24 40
1735 #define FF_PROFILE_DTS_HD_HRA 50
1736 #define FF_PROFILE_DTS_HD_MA 60
1737 #define FF_PROFILE_DTS_EXPRESS 70
1739 #define FF_PROFILE_MPEG2_422 0
1740 #define FF_PROFILE_MPEG2_HIGH 1
1741 #define FF_PROFILE_MPEG2_SS 2
1742 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1743 #define FF_PROFILE_MPEG2_MAIN 4
1744 #define FF_PROFILE_MPEG2_SIMPLE 5
1746 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1747 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1749 #define FF_PROFILE_H264_BASELINE 66
1750 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1751 #define FF_PROFILE_H264_MAIN 77
1752 #define FF_PROFILE_H264_EXTENDED 88
1753 #define FF_PROFILE_H264_HIGH 100
1754 #define FF_PROFILE_H264_HIGH_10 110
1755 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1756 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1757 #define FF_PROFILE_H264_HIGH_422 122
1758 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1759 #define FF_PROFILE_H264_STEREO_HIGH 128
1760 #define FF_PROFILE_H264_HIGH_444 144
1761 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1762 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1763 #define FF_PROFILE_H264_CAVLC_444 44
1765 #define FF_PROFILE_VC1_SIMPLE 0
1766 #define FF_PROFILE_VC1_MAIN 1
1767 #define FF_PROFILE_VC1_COMPLEX 2
1768 #define FF_PROFILE_VC1_ADVANCED 3
1770 #define FF_PROFILE_MPEG4_SIMPLE 0
1771 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1772 #define FF_PROFILE_MPEG4_CORE 2
1773 #define FF_PROFILE_MPEG4_MAIN 3
1774 #define FF_PROFILE_MPEG4_N_BIT 4
1775 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1776 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1777 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1778 #define FF_PROFILE_MPEG4_HYBRID 8
1779 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1780 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1781 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1782 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1783 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1784 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1785 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1787 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1788 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1789 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1790 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1791 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1793 #define FF_PROFILE_VP9_0 0
1794 #define FF_PROFILE_VP9_1 1
1795 #define FF_PROFILE_VP9_2 2
1796 #define FF_PROFILE_VP9_3 3
1798 #define FF_PROFILE_HEVC_MAIN 1
1799 #define FF_PROFILE_HEVC_MAIN_10 2
1800 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1801 #define FF_PROFILE_HEVC_REXT 4
1803 #define FF_PROFILE_VVC_MAIN_10 1
1804 #define FF_PROFILE_VVC_MAIN_10_444 33
1806 #define FF_PROFILE_AV1_MAIN 0
1807 #define FF_PROFILE_AV1_HIGH 1
1808 #define FF_PROFILE_AV1_PROFESSIONAL 2
1810 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1811 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1812 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1813 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1814 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1816 #define FF_PROFILE_SBC_MSBC 1
1818 #define FF_PROFILE_PRORES_PROXY 0
1819 #define FF_PROFILE_PRORES_LT 1
1820 #define FF_PROFILE_PRORES_STANDARD 2
1821 #define FF_PROFILE_PRORES_HQ 3
1822 #define FF_PROFILE_PRORES_4444 4
1823 #define FF_PROFILE_PRORES_XQ 5
1825 #define FF_PROFILE_ARIB_PROFILE_A 0
1826 #define FF_PROFILE_ARIB_PROFILE_C 1
1828 #define FF_PROFILE_KLVA_SYNC 0
1829 #define FF_PROFILE_KLVA_ASYNC 1
1833 * - encoding: Set by user.
1834 * - decoding: Set by libavcodec.
1837 #define FF_LEVEL_UNKNOWN -99
1840 * Skip loop filtering for selected frames.
1841 * - encoding: unused
1842 * - decoding: Set by user.
1844 enum AVDiscard skip_loop_filter;
1847 * Skip IDCT/dequantization for selected frames.
1848 * - encoding: unused
1849 * - decoding: Set by user.
1851 enum AVDiscard skip_idct;
1854 * Skip decoding for selected frames.
1855 * - encoding: unused
1856 * - decoding: Set by user.
1858 enum AVDiscard skip_frame;
1861 * Header containing style information for text subtitles.
1862 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
1863 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
1864 * the Format line following. It shouldn't include any Dialogue line.
1865 * - encoding: Set/allocated/freed by user (before avcodec_open2())
1866 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
1868 uint8_t *subtitle_header;
1869 int subtitle_header_size;
1871 #if FF_API_VBV_DELAY
1873 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
1874 * Used for compliant TS muxing.
1875 * - encoding: Set by libavcodec.
1876 * - decoding: unused.
1877 * @deprecated this value is now exported as a part of
1878 * AV_PKT_DATA_CPB_PROPERTIES packet side data
1880 attribute_deprecated
1885 * Audio only. The number of "priming" samples (padding) inserted by the
1886 * encoder at the beginning of the audio. I.e. this number of leading
1887 * decoded samples must be discarded by the caller to get the original audio
1888 * without leading padding.
1890 * - decoding: unused
1891 * - encoding: Set by libavcodec. The timestamps on the output packets are
1892 * adjusted by the encoder so that they always refer to the
1893 * first sample of the data actually contained in the packet,
1894 * including any added padding. E.g. if the timebase is
1895 * 1/samplerate and the timestamp of the first input sample is
1896 * 0, the timestamp of the first output packet will be
1899 int initial_padding;
1902 * - decoding: For codecs that store a framerate value in the compressed
1903 * bitstream, the decoder may export it here. { 0, 1} when
1905 * - encoding: May be used to signal the framerate of CFR content to an
1908 AVRational framerate;
1911 * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
1912 * - encoding: unused.
1913 * - decoding: Set by libavcodec before calling get_format()
1915 enum AVPixelFormat sw_pix_fmt;
1918 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
1919 * - encoding unused.
1920 * - decoding set by user.
1922 AVRational pkt_timebase;
1926 * - encoding: unused.
1927 * - decoding: set by libavcodec.
1929 const AVCodecDescriptor *codec_descriptor;
1932 * Current statistics for PTS correction.
1933 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
1934 * - encoding: unused
1936 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
1937 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
1938 int64_t pts_correction_last_pts; /// PTS of the last frame
1939 int64_t pts_correction_last_dts; /// DTS of the last frame
1942 * Character encoding of the input subtitles file.
1943 * - decoding: set by user
1944 * - encoding: unused
1949 * Subtitles character encoding mode. Formats or codecs might be adjusting
1950 * this setting (if they are doing the conversion themselves for instance).
1951 * - decoding: set by libavcodec
1952 * - encoding: unused
1954 int sub_charenc_mode;
1955 #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)
1956 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
1957 #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
1958 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
1961 * Skip processing alpha if supported by codec.
1962 * Note that if the format uses pre-multiplied alpha (common with VP6,
1963 * and recommended due to better video quality/compression)
1964 * the image will look as if alpha-blended onto a black background.
1965 * However for formats that do not use pre-multiplied alpha
1966 * there might be serious artefacts (though e.g. libswscale currently
1967 * assumes pre-multiplied alpha anyway).
1969 * - decoding: set by user
1970 * - encoding: unused
1975 * Number of samples to skip after a discontinuity
1976 * - decoding: unused
1977 * - encoding: set by libavcodec
1983 * @deprecated unused
1985 attribute_deprecated
1987 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
1988 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
1989 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
1993 * custom intra quantization matrix
1994 * - encoding: Set by user, can be NULL.
1995 * - decoding: unused.
1997 uint16_t *chroma_intra_matrix;
2000 * dump format separator.
2001 * can be ", " or "\n " or anything else
2002 * - encoding: Set by user.
2003 * - decoding: Set by user.
2005 uint8_t *dump_separator;
2008 * ',' separated list of allowed decoders.
2009 * If NULL then all are allowed
2010 * - encoding: unused
2011 * - decoding: set by user
2013 char *codec_whitelist;
2016 * Properties of the stream that gets decoded
2017 * - encoding: unused
2018 * - decoding: set by libavcodec
2020 unsigned properties;
2021 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
2022 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
2025 * Additional data associated with the entire coded stream.
2027 * - decoding: unused
2028 * - encoding: may be set by libavcodec after avcodec_open2().
2030 AVPacketSideData *coded_side_data;
2031 int nb_coded_side_data;
2034 * A reference to the AVHWFramesContext describing the input (for encoding)
2035 * or output (decoding) frames. The reference is set by the caller and
2036 * afterwards owned (and freed) by libavcodec - it should never be read by
2037 * the caller after being set.
2039 * - decoding: This field should be set by the caller from the get_format()
2040 * callback. The previous reference (if any) will always be
2041 * unreffed by libavcodec before the get_format() call.
2043 * If the default get_buffer2() is used with a hwaccel pixel
2044 * format, then this AVHWFramesContext will be used for
2045 * allocating the frame buffers.
2047 * - encoding: For hardware encoders configured to use a hwaccel pixel
2048 * format, this field should be set by the caller to a reference
2049 * to the AVHWFramesContext describing input frames.
2050 * AVHWFramesContext.format must be equal to
2051 * AVCodecContext.pix_fmt.
2053 * This field should be set before avcodec_open2() is called.
2055 AVBufferRef *hw_frames_ctx;
2058 * Control the form of AVSubtitle.rects[N]->ass
2059 * - decoding: set by user
2060 * - encoding: unused
2062 int sub_text_format;
2063 #define FF_SUB_TEXT_FMT_ASS 0
2064 #if FF_API_ASS_TIMING
2065 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
2069 * Audio only. The amount of padding (in samples) appended by the encoder to
2070 * the end of the audio. I.e. this number of decoded samples must be
2071 * discarded by the caller from the end of the stream to get the original
2072 * audio without any trailing padding.
2074 * - decoding: unused
2075 * - encoding: unused
2077 int trailing_padding;
2080 * The number of pixels per image to maximally accept.
2082 * - decoding: set by user
2083 * - encoding: set by user
2088 * A reference to the AVHWDeviceContext describing the device which will
2089 * be used by a hardware encoder/decoder. The reference is set by the
2090 * caller and afterwards owned (and freed) by libavcodec.
2092 * This should be used if either the codec device does not require
2093 * hardware frames or any that are used are to be allocated internally by
2094 * libavcodec. If the user wishes to supply any of the frames used as
2095 * encoder input or decoder output then hw_frames_ctx should be used
2096 * instead. When hw_frames_ctx is set in get_format() for a decoder, this
2097 * field will be ignored while decoding the associated stream segment, but
2098 * may again be used on a following one after another get_format() call.
2100 * For both encoders and decoders this field should be set before
2101 * avcodec_open2() is called and must not be written to thereafter.
2103 * Note that some decoders may require this field to be set initially in
2104 * order to support hw_frames_ctx at all - in that case, all frames
2105 * contexts used must be created on the same device.
2107 AVBufferRef *hw_device_ctx;
2110 * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
2111 * decoding (if active).
2112 * - encoding: unused
2113 * - decoding: Set by user (either before avcodec_open2(), or in the
2114 * AVCodecContext.get_format callback)
2119 * Video decoding only. Certain video codecs support cropping, meaning that
2120 * only a sub-rectangle of the decoded frame is intended for display. This
2121 * option controls how cropping is handled by libavcodec.
2123 * When set to 1 (the default), libavcodec will apply cropping internally.
2124 * I.e. it will modify the output frame width/height fields and offset the
2125 * data pointers (only by as much as possible while preserving alignment, or
2126 * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
2127 * the frames output by the decoder refer only to the cropped area. The
2128 * crop_* fields of the output frames will be zero.
2130 * When set to 0, the width/height fields of the output frames will be set
2131 * to the coded dimensions and the crop_* fields will describe the cropping
2132 * rectangle. Applying the cropping is left to the caller.
2134 * @warning When hardware acceleration with opaque output frames is used,
2135 * libavcodec is unable to apply cropping from the top/left border.
2137 * @note when this option is set to zero, the width/height fields of the
2138 * AVCodecContext and output AVFrames have different meanings. The codec
2139 * context fields store display dimensions (with the coded dimensions in
2140 * coded_width/height), while the frame fields store the coded dimensions
2141 * (with the display dimensions being determined by the crop_* fields).
2146 * Video decoding only. Sets the number of extra hardware frames which
2147 * the decoder will allocate for use by the caller. This must be set
2148 * before avcodec_open2() is called.
2150 * Some hardware decoders require all frames that they will use for
2151 * output to be defined in advance before decoding starts. For such
2152 * decoders, the hardware frame pool must therefore be of a fixed size.
2153 * The extra frames set here are on top of any number that the decoder
2154 * needs internally in order to operate normally (for example, frames
2155 * used as reference pictures).
2157 int extra_hw_frames;
2160 * The percentage of damaged samples to discard a frame.
2162 * - decoding: set by user
2163 * - encoding: unused
2165 int discard_damaged_percentage;
2168 * The number of samples per frame to maximally accept.
2170 * - decoding: set by user
2171 * - encoding: set by user
2173 int64_t max_samples;
2176 * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
2177 * metadata exported in frame, packet, or coded stream side data by
2178 * decoders and encoders.
2180 * - decoding: set by user
2181 * - encoding: set by user
2183 int export_side_data;
2186 * This callback is called at the beginning of each packet to get a data
2189 * The following field will be set in the packet before this callback is
2192 * This callback must use the above value to calculate the required buffer size,
2193 * which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
2195 * This callback must fill the following fields in the packet:
2196 * - data: alignment requirements for AVPacket apply, if any. Some architectures and
2197 * encoders may benefit from having aligned data.
2198 * - buf: must contain a pointer to an AVBufferRef structure. The packet's
2199 * data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
2200 * and av_buffer_ref().
2202 * If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2203 * avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2206 * The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2207 * They may be used for example to hint what use the buffer may get after being
2209 * Implementations of this callback may ignore flags they don't understand.
2210 * If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2211 * (read and/or written to if it is writable) later by libavcodec.
2213 * This callback must be thread-safe, as when frame threading is used, it may
2214 * be called from multiple threads simultaneously.
2216 * @see avcodec_default_get_encode_buffer()
2218 * - encoding: Set by libavcodec, user can override.
2219 * - decoding: unused
2221 int (*get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags);
2226 struct MpegEncContext;
2229 * @defgroup lavc_hwaccel AVHWAccel
2231 * @note Nothing in this structure should be accessed by the user. At some
2232 * point in future it will not be externally visible at all.
2236 typedef struct AVHWAccel {
2238 * Name of the hardware accelerated codec.
2239 * The name is globally unique among encoders and among decoders (but an
2240 * encoder and a decoder can share the same name).
2245 * Type of codec implemented by the hardware accelerator.
2247 * See AVMEDIA_TYPE_xxx
2249 enum AVMediaType type;
2252 * Codec implemented by the hardware accelerator.
2254 * See AV_CODEC_ID_xxx
2259 * Supported pixel format.
2261 * Only hardware accelerated formats are supported here.
2263 enum AVPixelFormat pix_fmt;
2266 * Hardware accelerated codec capabilities.
2267 * see AV_HWACCEL_CODEC_CAP_*
2271 /*****************************************************************
2272 * No fields below this line are part of the public API. They
2273 * may not be used outside of libavcodec and can be changed and
2275 * New public fields should be added right above.
2276 *****************************************************************
2280 * Allocate a custom buffer
2282 int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
2285 * Called at the beginning of each frame or field picture.
2287 * Meaningful frame information (codec specific) is guaranteed to
2288 * be parsed at this point. This function is mandatory.
2290 * Note that buf can be NULL along with buf_size set to 0.
2291 * Otherwise, this means the whole frame is available at this point.
2293 * @param avctx the codec context
2294 * @param buf the frame data buffer base
2295 * @param buf_size the size of the frame in bytes
2296 * @return zero if successful, a negative value otherwise
2298 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2301 * Callback for parameter data (SPS/PPS/VPS etc).
2303 * Useful for hardware decoders which keep persistent state about the
2304 * video parameters, and need to receive any changes to update that state.
2306 * @param avctx the codec context
2307 * @param type the nal unit type
2308 * @param buf the nal unit data buffer
2309 * @param buf_size the size of the nal unit in bytes
2310 * @return zero if successful, a negative value otherwise
2312 int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
2315 * Callback for each slice.
2317 * Meaningful slice information (codec specific) is guaranteed to
2318 * be parsed at this point. This function is mandatory.
2319 * The only exception is XvMC, that works on MB level.
2321 * @param avctx the codec context
2322 * @param buf the slice data buffer base
2323 * @param buf_size the size of the slice in bytes
2324 * @return zero if successful, a negative value otherwise
2326 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2329 * Called at the end of each frame or field picture.
2331 * The whole picture is parsed at this point and can now be sent
2332 * to the hardware accelerator. This function is mandatory.
2334 * @param avctx the codec context
2335 * @return zero if successful, a negative value otherwise
2337 int (*end_frame)(AVCodecContext *avctx);
2340 * Size of per-frame hardware accelerator private data.
2342 * Private data is allocated with av_mallocz() before
2343 * AVCodecContext.get_buffer() and deallocated after
2344 * AVCodecContext.release_buffer().
2346 int frame_priv_data_size;
2349 * Called for every Macroblock in a slice.
2351 * XvMC uses it to replace the ff_mpv_reconstruct_mb().
2352 * Instead of decoding to raw picture, MB parameters are
2353 * stored in an array provided by the video driver.
2355 * @param s the mpeg context
2357 void (*decode_mb)(struct MpegEncContext *s);
2360 * Initialize the hwaccel private data.
2362 * This will be called from ff_get_format(), after hwaccel and
2363 * hwaccel_context are set and the hwaccel private data in AVCodecInternal
2366 int (*init)(AVCodecContext *avctx);
2369 * Uninitialize the hwaccel private data.
2371 * This will be called from get_format() or avcodec_close(), after hwaccel
2372 * and hwaccel_context are already uninitialized.
2374 int (*uninit)(AVCodecContext *avctx);
2377 * Size of the private data to allocate in
2378 * AVCodecInternal.hwaccel_priv_data.
2383 * Internal hwaccel capabilities.
2388 * Fill the given hw_frames context with current codec parameters. Called
2389 * from get_format. Refer to avcodec_get_hw_frames_parameters() for
2392 * This CAN be called before AVHWAccel.init is called, and you must assume
2393 * that avctx->hwaccel_priv_data is invalid.
2395 int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
2399 * HWAccel is experimental and is thus avoided in favor of non experimental
2402 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2405 * Hardware acceleration should be used for decoding even if the codec level
2406 * used is unknown or higher than the maximum supported level reported by the
2409 * It's generally a good idea to pass this flag unless you have a specific
2410 * reason not to, as hardware tends to under-report supported levels.
2412 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2415 * Hardware acceleration can output YUV pixel formats with a different chroma
2416 * sampling than 4:2:0 and/or other than 8 bits per component.
2418 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2421 * Hardware acceleration should still be attempted for decoding when the
2422 * codec profile does not match the reported capabilities of the hardware.
2424 * For example, this can be used to try to decode baseline profile H.264
2425 * streams in hardware - it will often succeed, because many streams marked
2426 * as baseline profile actually conform to constrained baseline profile.
2428 * @warning If the stream is actually not supported then the behaviour is
2429 * undefined, and may include returning entirely incorrect output
2430 * while indicating success.
2432 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2438 #if FF_API_AVPICTURE
2440 * @defgroup lavc_picture AVPicture
2442 * Functions for working with AVPicture
2447 * Picture data structure.
2449 * Up to four components can be stored into it, the last component is
2451 * @deprecated use AVFrame or imgutils functions instead
2453 typedef struct AVPicture {
2454 attribute_deprecated
2455 uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
2456 attribute_deprecated
2457 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
2465 enum AVSubtitleType {
2468 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2471 * Plain text, the text field must be set by the decoder and is
2472 * authoritative. ass and pict fields may contain approximations.
2477 * Formatted text, the ass field must be set by the decoder and is
2478 * authoritative. pict and text fields may contain approximations.
2483 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
2485 typedef struct AVSubtitleRect {
2486 int x; ///< top left corner of pict, undefined when pict is not set
2487 int y; ///< top left corner of pict, undefined when pict is not set
2488 int w; ///< width of pict, undefined when pict is not set
2489 int h; ///< height of pict, undefined when pict is not set
2490 int nb_colors; ///< number of colors in pict, undefined when pict is not set
2492 #if FF_API_AVPICTURE
2494 * @deprecated unused
2496 attribute_deprecated
2500 * data+linesize for the bitmap of this subtitle.
2501 * Can be set for text/ass as well once they are rendered.
2506 enum AVSubtitleType type;
2508 char *text; ///< 0 terminated plain UTF-8 text
2511 * 0 terminated ASS/SSA compatible event line.
2512 * The presentation of this is unaffected by the other values in this
2520 typedef struct AVSubtitle {
2521 uint16_t format; /* 0 = graphics */
2522 uint32_t start_display_time; /* relative to packet pts, in ms */
2523 uint32_t end_display_time; /* relative to packet pts, in ms */
2525 AVSubtitleRect **rects;
2526 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2530 * Return the LIBAVCODEC_VERSION_INT constant.
2532 unsigned avcodec_version(void);
2535 * Return the libavcodec build-time configuration.
2537 const char *avcodec_configuration(void);
2540 * Return the libavcodec license.
2542 const char *avcodec_license(void);
2545 * Allocate an AVCodecContext and set its fields to default values. The
2546 * resulting struct should be freed with avcodec_free_context().
2548 * @param codec if non-NULL, allocate private data and initialize defaults
2549 * for the given codec. It is illegal to then call avcodec_open2()
2550 * with a different codec.
2551 * If NULL, then the codec-specific defaults won't be initialized,
2552 * which may result in suboptimal default settings (this is
2553 * important mainly for encoders, e.g. libx264).
2555 * @return An AVCodecContext filled with default values or NULL on failure.
2557 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
2560 * Free the codec context and everything associated with it and write NULL to
2561 * the provided pointer.
2563 void avcodec_free_context(AVCodecContext **avctx);
2565 #if FF_API_GET_CONTEXT_DEFAULTS
2567 * @deprecated This function should not be used, as closing and opening a codec
2568 * context multiple time is not supported. A new codec context should be
2569 * allocated for each new use.
2571 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
2575 * Get the AVClass for AVCodecContext. It can be used in combination with
2576 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2578 * @see av_opt_find().
2580 const AVClass *avcodec_get_class(void);
2582 #if FF_API_GET_FRAME_CLASS
2584 * @deprecated This function should not be used.
2586 attribute_deprecated
2587 const AVClass *avcodec_get_frame_class(void);
2591 * Get the AVClass for AVSubtitleRect. It can be used in combination with
2592 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2594 * @see av_opt_find().
2596 const AVClass *avcodec_get_subtitle_rect_class(void);
2598 #if FF_API_COPY_CONTEXT
2600 * Copy the settings of the source AVCodecContext into the destination
2601 * AVCodecContext. The resulting destination codec context will be
2602 * unopened, i.e. you are required to call avcodec_open2() before you
2603 * can use this AVCodecContext to decode/encode video/audio data.
2605 * @param dest target codec context, should be initialized with
2606 * avcodec_alloc_context3(NULL), but otherwise uninitialized
2607 * @param src source codec context
2608 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
2610 * @deprecated The semantics of this function are ill-defined and it should not
2611 * be used. If you need to transfer the stream parameters from one codec context
2612 * to another, use an intermediate AVCodecParameters instance and the
2613 * avcodec_parameters_from_context() / avcodec_parameters_to_context()
2616 attribute_deprecated
2617 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
2621 * Fill the parameters struct based on the values from the supplied codec
2622 * context. Any allocated fields in par are freed and replaced with duplicates
2623 * of the corresponding fields in codec.
2625 * @return >= 0 on success, a negative AVERROR code on failure
2627 int avcodec_parameters_from_context(AVCodecParameters *par,
2628 const AVCodecContext *codec);
2631 * Fill the codec context based on the values from the supplied codec
2632 * parameters. Any allocated fields in codec that have a corresponding field in
2633 * par are freed and replaced with duplicates of the corresponding field in par.
2634 * Fields in codec that do not have a counterpart in par are not touched.
2636 * @return >= 0 on success, a negative AVERROR code on failure.
2638 int avcodec_parameters_to_context(AVCodecContext *codec,
2639 const AVCodecParameters *par);
2642 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2643 * function the context has to be allocated with avcodec_alloc_context3().
2645 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2646 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2647 * retrieving a codec.
2649 * @warning This function is not thread safe!
2651 * @note Always call this function before using decoding routines (such as
2652 * @ref avcodec_receive_frame()).
2655 * av_dict_set(&opts, "b", "2.5M", 0);
2656 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2660 * context = avcodec_alloc_context3(codec);
2662 * if (avcodec_open2(context, codec, opts) < 0)
2666 * @param avctx The context to initialize.
2667 * @param codec The codec to open this context for. If a non-NULL codec has been
2668 * previously passed to avcodec_alloc_context3() or
2669 * for this context, then this parameter MUST be either NULL or
2670 * equal to the previously passed codec.
2671 * @param options A dictionary filled with AVCodecContext and codec-private options.
2672 * On return this object will be filled with options that were not found.
2674 * @return zero on success, a negative value on error
2675 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2676 * av_dict_set(), av_opt_find().
2678 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2681 * Close a given AVCodecContext and free all the data associated with it
2682 * (but not the AVCodecContext itself).
2684 * Calling this function on an AVCodecContext that hasn't been opened will free
2685 * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2686 * codec. Subsequent calls will do nothing.
2688 * @note Do not use this function. Use avcodec_free_context() to destroy a
2689 * codec context (either open or closed). Opening and closing a codec context
2690 * multiple times is not supported anymore -- use multiple codec contexts
2693 int avcodec_close(AVCodecContext *avctx);
2696 * Free all allocated data in the given subtitle struct.
2698 * @param sub AVSubtitle to free.
2700 void avsubtitle_free(AVSubtitle *sub);
2707 * @addtogroup lavc_decoding
2712 * The default callback for AVCodecContext.get_buffer2(). It is made public so
2713 * it can be called by custom get_buffer2() implementations for decoders without
2714 * AV_CODEC_CAP_DR1 set.
2716 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
2719 * The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2720 * it can be called by custom get_encode_buffer() implementations for encoders without
2721 * AV_CODEC_CAP_DR1 set.
2723 int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags);
2726 * Modify width and height values so that they will result in a memory
2727 * buffer that is acceptable for the codec if you do not use any horizontal
2730 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2732 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
2735 * Modify width and height values so that they will result in a memory
2736 * buffer that is acceptable for the codec if you also ensure that all
2737 * line sizes are a multiple of the respective linesize_align[i].
2739 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2741 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
2742 int linesize_align[AV_NUM_DATA_POINTERS]);
2745 * Converts AVChromaLocation to swscale x/y chroma position.
2747 * The positions represent the chroma (0,0) position in a coordinates system
2748 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2750 * @param xpos horizontal chroma sample position
2751 * @param ypos vertical chroma sample position
2753 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
2756 * Converts swscale x/y chroma position to AVChromaLocation.
2758 * The positions represent the chroma (0,0) position in a coordinates system
2759 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
2761 * @param xpos horizontal chroma sample position
2762 * @param ypos vertical chroma sample position
2764 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
2766 #if FF_API_OLD_ENCDEC
2768 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
2770 * Some decoders may support multiple frames in a single AVPacket. Such
2771 * decoders would then just decode the first frame and the return value would be
2772 * less than the packet size. In this case, avcodec_decode_audio4 has to be
2773 * called again with an AVPacket containing the remaining data in order to
2774 * decode the second frame, etc... Even if no frames are returned, the packet
2775 * needs to be fed to the decoder with remaining data until it is completely
2776 * consumed or an error occurs.
2778 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2779 * and output. This means that for some packets they will not immediately
2780 * produce decoded output and need to be flushed at the end of decoding to get
2781 * all the decoded data. Flushing is done by calling this function with packets
2782 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2783 * returning samples. It is safe to flush even those decoders that are not
2784 * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
2786 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2787 * larger than the actual read bytes because some optimized bitstream
2788 * readers read 32 or 64 bits at once and could read over the end.
2790 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2791 * before packets may be fed to the decoder.
2793 * @param avctx the codec context
2794 * @param[out] frame The AVFrame in which to store decoded audio samples.
2795 * The decoder will allocate a buffer for the decoded frame by
2796 * calling the AVCodecContext.get_buffer2() callback.
2797 * When AVCodecContext.refcounted_frames is set to 1, the frame is
2798 * reference counted and the returned reference belongs to the
2799 * caller. The caller must release the frame using av_frame_unref()
2800 * when the frame is no longer needed. The caller may safely write
2801 * to the frame if av_frame_is_writable() returns 1.
2802 * When AVCodecContext.refcounted_frames is set to 0, the returned
2803 * reference belongs to the decoder and is valid only until the
2804 * next call to this function or until closing or flushing the
2805 * decoder. The caller may not write to it.
2806 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
2807 * non-zero. Note that this field being set to zero
2808 * does not mean that an error has occurred. For
2809 * decoders with AV_CODEC_CAP_DELAY set, no given decode
2810 * call is guaranteed to produce a frame.
2811 * @param[in] avpkt The input AVPacket containing the input buffer.
2812 * At least avpkt->data and avpkt->size should be set. Some
2813 * decoders might also require additional fields to be set.
2814 * @return A negative error code is returned if an error occurred during
2815 * decoding, otherwise the number of bytes consumed from the input
2816 * AVPacket is returned.
2818 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
2820 attribute_deprecated
2821 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
2822 int *got_frame_ptr, const AVPacket *avpkt);
2825 * Decode the video frame of size avpkt->size from avpkt->data into picture.
2826 * Some decoders may support multiple frames in a single AVPacket, such
2827 * decoders would then just decode the first frame.
2829 * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
2830 * the actual read bytes because some optimized bitstream readers read 32 or 64
2831 * bits at once and could read over the end.
2833 * @warning The end of the input buffer buf should be set to 0 to ensure that
2834 * no overreading happens for damaged MPEG streams.
2836 * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
2837 * between input and output, these need to be fed with avpkt->data=NULL,
2838 * avpkt->size=0 at the end to return the remaining frames.
2840 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2841 * before packets may be fed to the decoder.
2843 * @param avctx the codec context
2844 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
2845 * Use av_frame_alloc() to get an AVFrame. The codec will
2846 * allocate memory for the actual bitmap by calling the
2847 * AVCodecContext.get_buffer2() callback.
2848 * When AVCodecContext.refcounted_frames is set to 1, the frame is
2849 * reference counted and the returned reference belongs to the
2850 * caller. The caller must release the frame using av_frame_unref()
2851 * when the frame is no longer needed. The caller may safely write
2852 * to the frame if av_frame_is_writable() returns 1.
2853 * When AVCodecContext.refcounted_frames is set to 0, the returned
2854 * reference belongs to the decoder and is valid only until the
2855 * next call to this function or until closing or flushing the
2856 * decoder. The caller may not write to it.
2858 * @param[in] avpkt The input AVPacket containing the input buffer.
2859 * You can create such packet with av_init_packet() and by then setting
2860 * data and size, some decoders might in addition need other fields like
2861 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
2863 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
2864 * @return On error a negative value is returned, otherwise the number of bytes
2865 * used or zero if no frame could be decompressed.
2867 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
2869 attribute_deprecated
2870 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
2871 int *got_picture_ptr,
2872 const AVPacket *avpkt);
2876 * Decode a subtitle message.
2877 * Return a negative value on error, otherwise return the number of bytes used.
2878 * If no subtitle could be decompressed, got_sub_ptr is zero.
2879 * Otherwise, the subtitle is stored in *sub.
2880 * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
2881 * simplicity, because the performance difference is expected to be negligible
2882 * and reusing a get_buffer written for video codecs would probably perform badly
2883 * due to a potentially very different allocation pattern.
2885 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2886 * and output. This means that for some packets they will not immediately
2887 * produce decoded output and need to be flushed at the end of decoding to get
2888 * all the decoded data. Flushing is done by calling this function with packets
2889 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2890 * returning subtitles. It is safe to flush even those decoders that are not
2891 * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
2893 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2894 * before packets may be fed to the decoder.
2896 * @param avctx the codec context
2897 * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
2898 * must be freed with avsubtitle_free if *got_sub_ptr is set.
2899 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
2900 * @param[in] avpkt The input AVPacket containing the input buffer.
2902 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
2907 * Supply raw packet data as input to a decoder.
2909 * Internally, this call will copy relevant AVCodecContext fields, which can
2910 * influence decoding per-packet, and apply them when the packet is actually
2911 * decoded. (For example AVCodecContext.skip_frame, which might direct the
2912 * decoder to drop the frame contained by the packet sent with this function.)
2914 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2915 * larger than the actual read bytes because some optimized bitstream
2916 * readers read 32 or 64 bits at once and could read over the end.
2918 * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
2919 * on the same AVCodecContext. It will return unexpected results now
2920 * or in future libavcodec versions.
2922 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2923 * before packets may be fed to the decoder.
2925 * @param avctx codec context
2926 * @param[in] avpkt The input AVPacket. Usually, this will be a single video
2927 * frame, or several complete audio frames.
2928 * Ownership of the packet remains with the caller, and the
2929 * decoder will not write to the packet. The decoder may create
2930 * a reference to the packet data (or copy it if the packet is
2931 * not reference-counted).
2932 * Unlike with older APIs, the packet is always fully consumed,
2933 * and if it contains multiple frames (e.g. some audio codecs),
2934 * will require you to call avcodec_receive_frame() multiple
2935 * times afterwards before you can send a new packet.
2936 * It can be NULL (or an AVPacket with data set to NULL and
2937 * size set to 0); in this case, it is considered a flush
2938 * packet, which signals the end of the stream. Sending the
2939 * first flush packet will return success. Subsequent ones are
2940 * unnecessary and will return AVERROR_EOF. If the decoder
2941 * still has frames buffered, it will return them after sending
2944 * @return 0 on success, otherwise negative error code:
2945 * AVERROR(EAGAIN): input is not accepted in the current state - user
2946 * must read output with avcodec_receive_frame() (once
2947 * all output is read, the packet should be resent, and
2948 * the call will not fail with EAGAIN).
2949 * AVERROR_EOF: the decoder has been flushed, and no new packets can
2950 * be sent to it (also returned if more than 1 flush
2952 * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
2953 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
2954 * other errors: legitimate decoding errors
2956 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
2959 * Return decoded output data from a decoder.
2961 * @param avctx codec context
2962 * @param frame This will be set to a reference-counted video or audio
2963 * frame (depending on the decoder type) allocated by the
2964 * decoder. Note that the function will always call
2965 * av_frame_unref(frame) before doing anything else.
2968 * 0: success, a frame was returned
2969 * AVERROR(EAGAIN): output is not available in this state - user must try
2971 * AVERROR_EOF: the decoder has been fully flushed, and there will be
2972 * no more output frames
2973 * AVERROR(EINVAL): codec not opened, or it is an encoder
2974 * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
2975 * with respect to first decoded frame. Applicable
2976 * when flag AV_CODEC_FLAG_DROPCHANGED is set.
2977 * other negative values: legitimate decoding errors
2979 int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
2982 * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
2983 * to retrieve buffered output packets.
2985 * @param avctx codec context
2986 * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
2987 * Ownership of the frame remains with the caller, and the
2988 * encoder will not write to the frame. The encoder may create
2989 * a reference to the frame data (or copy it if the frame is
2990 * not reference-counted).
2991 * It can be NULL, in which case it is considered a flush
2992 * packet. This signals the end of the stream. If the encoder
2993 * still has packets buffered, it will return them after this
2994 * call. Once flushing mode has been entered, additional flush
2995 * packets are ignored, and sending frames will return
2999 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
3000 * can have any number of samples.
3001 * If it is not set, frame->nb_samples must be equal to
3002 * avctx->frame_size for all frames except the last.
3003 * The final frame may be smaller than avctx->frame_size.
3004 * @return 0 on success, otherwise negative error code:
3005 * AVERROR(EAGAIN): input is not accepted in the current state - user
3006 * must read output with avcodec_receive_packet() (once
3007 * all output is read, the packet should be resent, and
3008 * the call will not fail with EAGAIN).
3009 * AVERROR_EOF: the encoder has been flushed, and no new frames can
3011 * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
3012 * decoder, or requires flush
3013 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
3014 * other errors: legitimate encoding errors
3016 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
3019 * Read encoded data from the encoder.
3021 * @param avctx codec context
3022 * @param avpkt This will be set to a reference-counted packet allocated by the
3023 * encoder. Note that the function will always call
3024 * av_packet_unref(avpkt) before doing anything else.
3025 * @return 0 on success, otherwise negative error code:
3026 * AVERROR(EAGAIN): output is not available in the current state - user
3027 * must try to send input
3028 * AVERROR_EOF: the encoder has been fully flushed, and there will be
3029 * no more output packets
3030 * AVERROR(EINVAL): codec not opened, or it is a decoder
3031 * other errors: legitimate encoding errors
3033 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
3036 * Create and return a AVHWFramesContext with values adequate for hardware
3037 * decoding. This is meant to get called from the get_format callback, and is
3038 * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
3039 * This API is for decoding with certain hardware acceleration modes/APIs only.
3041 * The returned AVHWFramesContext is not initialized. The caller must do this
3042 * with av_hwframe_ctx_init().
3044 * Calling this function is not a requirement, but makes it simpler to avoid
3045 * codec or hardware API specific details when manually allocating frames.
3047 * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
3048 * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
3049 * it unnecessary to call this function or having to care about
3050 * AVHWFramesContext initialization at all.
3052 * There are a number of requirements for calling this function:
3054 * - It must be called from get_format with the same avctx parameter that was
3055 * passed to get_format. Calling it outside of get_format is not allowed, and
3056 * can trigger undefined behavior.
3057 * - The function is not always supported (see description of return values).
3058 * Even if this function returns successfully, hwaccel initialization could
3059 * fail later. (The degree to which implementations check whether the stream
3060 * is actually supported varies. Some do this check only after the user's
3061 * get_format callback returns.)
3062 * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
3063 * user decides to use a AVHWFramesContext prepared with this API function,
3064 * the user must return the same hw_pix_fmt from get_format.
3065 * - The device_ref passed to this function must support the given hw_pix_fmt.
3066 * - After calling this API function, it is the user's responsibility to
3067 * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
3068 * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
3069 * before returning from get_format (this is implied by the normal
3070 * AVCodecContext.hw_frames_ctx API rules).
3071 * - The AVHWFramesContext parameters may change every time time get_format is
3072 * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
3073 * you are inherently required to go through this process again on every
3075 * - It is perfectly possible to call this function without actually using
3076 * the resulting AVHWFramesContext. One use-case might be trying to reuse a
3077 * previously initialized AVHWFramesContext, and calling this API function
3078 * only to test whether the required frame parameters have changed.
3079 * - Fields that use dynamically allocated values of any kind must not be set
3080 * by the user unless setting them is explicitly allowed by the documentation.
3081 * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
3082 * the new free callback must call the potentially set previous free callback.
3083 * This API call may set any dynamically allocated fields, including the free
3086 * The function will set at least the following fields on AVHWFramesContext
3087 * (potentially more, depending on hwaccel API):
3089 * - All fields set by av_hwframe_ctx_alloc().
3090 * - Set the format field to hw_pix_fmt.
3091 * - Set the sw_format field to the most suited and most versatile format. (An
3092 * implication is that this will prefer generic formats over opaque formats
3093 * with arbitrary restrictions, if possible.)
3094 * - Set the width/height fields to the coded frame size, rounded up to the
3095 * API-specific minimum alignment.
3096 * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
3097 * field to the number of maximum reference surfaces possible with the codec,
3098 * plus 1 surface for the user to work (meaning the user can safely reference
3099 * at most 1 decoded surface at a time), plus additional buffering introduced
3100 * by frame threading. If the hwaccel does not require pre-allocation, the
3101 * field is left to 0, and the decoder will allocate new surfaces on demand
3103 * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
3106 * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
3107 * with basic frame parameters set.
3109 * The function is stateless, and does not change the AVCodecContext or the
3110 * device_ref AVHWDeviceContext.
3112 * @param avctx The context which is currently calling get_format, and which
3113 * implicitly contains all state needed for filling the returned
3114 * AVHWFramesContext properly.
3115 * @param device_ref A reference to the AVHWDeviceContext describing the device
3116 * which will be used by the hardware decoder.
3117 * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
3118 * @param out_frames_ref On success, set to a reference to an _uninitialized_
3119 * AVHWFramesContext, created from the given device_ref.
3120 * Fields will be set to values required for decoding.
3121 * Not changed if an error is returned.
3122 * @return zero on success, a negative value on error. The following error codes
3123 * have special semantics:
3124 * AVERROR(ENOENT): the decoder does not support this functionality. Setup
3125 * is always manual, or it is a decoder which does not
3126 * support setting AVCodecContext.hw_frames_ctx at all,
3127 * or it is a software format.
3128 * AVERROR(EINVAL): it is known that hardware decoding is not supported for
3129 * this configuration, or the device_ref is not supported
3130 * for the hwaccel referenced by hw_pix_fmt.
3132 int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
3133 AVBufferRef *device_ref,
3134 enum AVPixelFormat hw_pix_fmt,
3135 AVBufferRef **out_frames_ref);
3140 * @defgroup lavc_parsing Frame parsing
3144 enum AVPictureStructure {
3145 AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
3146 AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
3147 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
3148 AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
3151 typedef struct AVCodecParserContext {
3153 struct AVCodecParser *parser;
3154 int64_t frame_offset; /* offset of the current frame */
3155 int64_t cur_offset; /* current offset
3156 (incremented by each av_parser_parse()) */
3157 int64_t next_frame_offset; /* offset of the next frame */
3159 int pict_type; /* XXX: Put it back in AVCodecContext. */
3161 * This field is used for proper frame duration computation in lavf.
3162 * It signals, how much longer the frame duration of the current frame
3163 * is compared to normal frame duration.
3165 * frame_duration = (1 + repeat_pict) * time_base
3167 * It is used by codecs like H.264 to display telecined material.
3169 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
3170 int64_t pts; /* pts of the current frame */
3171 int64_t dts; /* dts of the current frame */
3176 int fetch_timestamp;
3178 #define AV_PARSER_PTS_NB 4
3179 int cur_frame_start_index;
3180 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
3181 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
3182 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
3185 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
3186 #define PARSER_FLAG_ONCE 0x0002
3187 /// Set if the parser has a valid file offset
3188 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
3189 #define PARSER_FLAG_USE_CODEC_TS 0x1000
3191 int64_t offset; ///< byte offset from starting packet start
3192 int64_t cur_frame_end[AV_PARSER_PTS_NB];
3195 * Set by parser to 1 for key frames and 0 for non-key frames.
3196 * It is initialized to -1, so if the parser doesn't set this flag,
3197 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
3202 // Timestamp generation support:
3204 * Synchronization point for start of timestamp generation.
3206 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
3209 * For example, this corresponds to presence of H.264 buffering period
3215 * Offset of the current timestamp against last timestamp sync point in
3216 * units of AVCodecContext.time_base.
3218 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3219 * contain a valid timestamp offset.
3221 * Note that the timestamp of sync point has usually a nonzero
3222 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
3223 * the next frame after timestamp sync point will be usually 1.
3225 * For example, this corresponds to H.264 cpb_removal_delay.
3227 int dts_ref_dts_delta;
3230 * Presentation delay of current frame in units of AVCodecContext.time_base.
3232 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3233 * contain valid non-negative timestamp delta (presentation time of a frame
3234 * must not lie in the past).
3236 * This delay represents the difference between decoding and presentation
3237 * time of the frame.
3239 * For example, this corresponds to H.264 dpb_output_delay.
3244 * Position of the packet in file.
3246 * Analogous to cur_frame_pts/dts
3248 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
3251 * Byte position of currently parsed frame in stream.
3256 * Previous frame byte position.
3261 * Duration of the current frame.
3262 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
3263 * For all other types, this is in units of AVCodecContext.time_base.
3267 enum AVFieldOrder field_order;
3270 * Indicate whether a picture is coded as a frame, top field or bottom field.
3272 * For example, H.264 field_pic_flag equal to 0 corresponds to
3273 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
3274 * equal to 1 and bottom_field_flag equal to 0 corresponds to
3275 * AV_PICTURE_STRUCTURE_TOP_FIELD.
3277 enum AVPictureStructure picture_structure;
3280 * Picture number incremented in presentation or output order.
3281 * This field may be reinitialized at the first picture of a new sequence.
3283 * For example, this corresponds to H.264 PicOrderCnt.
3285 int output_picture_number;
3288 * Dimensions of the decoded video intended for presentation.
3294 * Dimensions of the coded video.
3300 * The format of the coded data, corresponds to enum AVPixelFormat for video
3301 * and for enum AVSampleFormat for audio.
3303 * Note that a decoder can have considerable freedom in how exactly it
3304 * decodes the data, so the format reported here might be different from the
3305 * one returned by a decoder.
3308 } AVCodecParserContext;
3310 typedef struct AVCodecParser {
3311 int codec_ids[5]; /* several codec IDs are permitted */
3313 int (*parser_init)(AVCodecParserContext *s);
3314 /* This callback never returns an error, a negative value means that
3315 * the frame start was in a previous packet. */
3316 int (*parser_parse)(AVCodecParserContext *s,
3317 AVCodecContext *avctx,
3318 const uint8_t **poutbuf, int *poutbuf_size,
3319 const uint8_t *buf, int buf_size);
3320 void (*parser_close)(AVCodecParserContext *s);
3321 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
3325 * Iterate over all registered codec parsers.
3327 * @param opaque a pointer where libavcodec will store the iteration state. Must
3328 * point to NULL to start the iteration.
3330 * @return the next registered codec parser or NULL when the iteration is
3333 const AVCodecParser *av_parser_iterate(void **opaque);
3335 AVCodecParserContext *av_parser_init(int codec_id);
3340 * @param s parser context.
3341 * @param avctx codec context.
3342 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
3343 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
3344 * @param buf input buffer.
3345 * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
3346 size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
3347 To signal EOF, this should be 0 (so that the last frame
3349 * @param pts input presentation timestamp.
3350 * @param dts input decoding timestamp.
3351 * @param pos input byte position in stream.
3352 * @return the number of bytes of the input bitstream used.
3357 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
3364 * decode_frame(data, size);
3368 int av_parser_parse2(AVCodecParserContext *s,
3369 AVCodecContext *avctx,
3370 uint8_t **poutbuf, int *poutbuf_size,
3371 const uint8_t *buf, int buf_size,
3372 int64_t pts, int64_t dts,
3375 #if FF_API_PARSER_CHANGE
3377 * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
3378 * @deprecated Use dump_extradata, remove_extra or extract_extradata
3379 * bitstream filters instead.
3381 attribute_deprecated
3382 int av_parser_change(AVCodecParserContext *s,
3383 AVCodecContext *avctx,
3384 uint8_t **poutbuf, int *poutbuf_size,
3385 const uint8_t *buf, int buf_size, int keyframe);
3387 void av_parser_close(AVCodecParserContext *s);
3395 * @addtogroup lavc_encoding
3399 #if FF_API_OLD_ENCDEC
3401 * Encode a frame of audio.
3403 * Takes input samples from frame and writes the next output packet, if
3404 * available, to avpkt. The output packet does not necessarily contain data for
3405 * the most recent frame, as encoders can delay, split, and combine input frames
3406 * internally as needed.
3408 * @param avctx codec context
3409 * @param avpkt output AVPacket.
3410 * The user can supply an output buffer by setting
3411 * avpkt->data and avpkt->size prior to calling the
3412 * function, but if the size of the user-provided data is not
3413 * large enough, encoding will fail. If avpkt->data and
3414 * avpkt->size are set, avpkt->destruct must also be set. All
3415 * other AVPacket fields will be reset by the encoder using
3416 * av_init_packet(). If avpkt->data is NULL, the encoder will
3417 * allocate it. The encoder will set avpkt->size to the size
3418 * of the output packet.
3420 * If this function fails or produces no output, avpkt will be
3421 * freed using av_packet_unref().
3422 * @param[in] frame AVFrame containing the raw audio data to be encoded.
3423 * May be NULL when flushing an encoder that has the
3424 * AV_CODEC_CAP_DELAY capability set.
3425 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
3426 * can have any number of samples.
3427 * If it is not set, frame->nb_samples must be equal to
3428 * avctx->frame_size for all frames except the last.
3429 * The final frame may be smaller than avctx->frame_size.
3430 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
3431 * output packet is non-empty, and to 0 if it is
3432 * empty. If the function returns an error, the
3433 * packet can be assumed to be invalid, and the
3434 * value of got_packet_ptr is undefined and should
3436 * @return 0 on success, negative error code on failure
3438 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead.
3439 * If allowed and required, set AVCodecContext.get_encode_buffer to
3440 * a custom function to pass user supplied output buffers.
3442 attribute_deprecated
3443 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
3444 const AVFrame *frame, int *got_packet_ptr);
3447 * Encode a frame of video.
3449 * Takes input raw video data from frame and writes the next output packet, if
3450 * available, to avpkt. The output packet does not necessarily contain data for
3451 * the most recent frame, as encoders can delay and reorder input frames
3452 * internally as needed.
3454 * @param avctx codec context
3455 * @param avpkt output AVPacket.
3456 * The user can supply an output buffer by setting
3457 * avpkt->data and avpkt->size prior to calling the
3458 * function, but if the size of the user-provided data is not
3459 * large enough, encoding will fail. All other AVPacket fields
3460 * will be reset by the encoder using av_init_packet(). If
3461 * avpkt->data is NULL, the encoder will allocate it.
3462 * The encoder will set avpkt->size to the size of the
3463 * output packet. The returned data (if any) belongs to the
3464 * caller, he is responsible for freeing it.
3466 * If this function fails or produces no output, avpkt will be
3467 * freed using av_packet_unref().
3468 * @param[in] frame AVFrame containing the raw video data to be encoded.
3469 * May be NULL when flushing an encoder that has the
3470 * AV_CODEC_CAP_DELAY capability set.
3471 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
3472 * output packet is non-empty, and to 0 if it is
3473 * empty. If the function returns an error, the
3474 * packet can be assumed to be invalid, and the
3475 * value of got_packet_ptr is undefined and should
3477 * @return 0 on success, negative error code on failure
3479 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead.
3480 * If allowed and required, set AVCodecContext.get_encode_buffer to
3481 * a custom function to pass user supplied output buffers.
3483 attribute_deprecated
3484 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
3485 const AVFrame *frame, int *got_packet_ptr);
3488 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3489 const AVSubtitle *sub);
3496 #if FF_API_AVPICTURE
3498 * @addtogroup lavc_picture
3503 * @deprecated unused
3505 attribute_deprecated
3506 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
3509 * @deprecated unused
3511 attribute_deprecated
3512 void avpicture_free(AVPicture *picture);
3515 * @deprecated use av_image_fill_arrays() instead.
3517 attribute_deprecated
3518 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
3519 enum AVPixelFormat pix_fmt, int width, int height);
3522 * @deprecated use av_image_copy_to_buffer() instead.
3524 attribute_deprecated
3525 int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
3526 int width, int height,
3527 unsigned char *dest, int dest_size);
3530 * @deprecated use av_image_get_buffer_size() instead.
3532 attribute_deprecated
3533 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
3536 * @deprecated av_image_copy() instead.
3538 attribute_deprecated
3539 void av_picture_copy(AVPicture *dst, const AVPicture *src,
3540 enum AVPixelFormat pix_fmt, int width, int height);
3543 * @deprecated unused
3545 attribute_deprecated
3546 int av_picture_crop(AVPicture *dst, const AVPicture *src,
3547 enum AVPixelFormat pix_fmt, int top_band, int left_band);
3550 * @deprecated unused
3552 attribute_deprecated
3553 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
3554 int padtop, int padbottom, int padleft, int padright, int *color);
3562 * @defgroup lavc_misc Utility functions
3565 * Miscellaneous utility functions related to both encoding and decoding
3571 * @defgroup lavc_misc_pixfmt Pixel formats
3573 * Functions for working with pixel formats.
3578 * Return a value representing the fourCC code associated to the
3579 * pixel format pix_fmt, or 0 if no associated fourCC code can be
3582 unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
3585 * Find the best pixel format to convert to given a certain source pixel
3586 * format. When converting from one pixel format to another, information loss
3587 * may occur. For example, when converting from RGB24 to GRAY, the color
3588 * information will be lost. Similarly, other losses occur when converting from
3589 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
3590 * the given pixel formats should be used to suffer the least amount of loss.
3591 * The pixel formats from which it chooses one, are determined by the
3592 * pix_fmt_list parameter.
3595 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
3596 * @param[in] src_pix_fmt source pixel format
3597 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
3598 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
3599 * @return The best pixel format to convert to or -1 if none was found.
3601 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
3602 enum AVPixelFormat src_pix_fmt,
3603 int has_alpha, int *loss_ptr);
3605 #if FF_API_AVCODEC_PIX_FMT
3607 * @deprecated see av_get_pix_fmt_loss()
3609 attribute_deprecated
3610 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
3613 * @deprecated see av_find_best_pix_fmt_of_2()
3615 attribute_deprecated
3616 enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
3617 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
3619 attribute_deprecated
3620 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
3621 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
3624 enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
3630 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
3633 * Return a name for the specified profile, if available.
3635 * @param codec the codec that is searched for the given profile
3636 * @param profile the profile value for which a name is requested
3637 * @return A name for the profile if found, NULL otherwise.
3639 const char *av_get_profile_name(const AVCodec *codec, int profile);
3642 * Return a name for the specified profile, if available.
3644 * @param codec_id the ID of the codec to which the requested profile belongs
3645 * @param profile the profile value for which a name is requested
3646 * @return A name for the profile if found, NULL otherwise.
3648 * @note unlike av_get_profile_name(), which searches a list of profiles
3649 * supported by a specific decoder or encoder implementation, this
3650 * function searches the list of profiles from the AVCodecDescriptor
3652 const char *avcodec_profile_name(enum AVCodecID codec_id, int profile);
3654 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
3655 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
3656 //FIXME func typedef
3659 * Fill AVFrame audio data and linesize pointers.
3661 * The buffer buf must be a preallocated buffer with a size big enough
3662 * to contain the specified samples amount. The filled AVFrame data
3663 * pointers will point to this buffer.
3665 * AVFrame extended_data channel pointers are allocated if necessary for
3668 * @param frame the AVFrame
3669 * frame->nb_samples must be set prior to calling the
3670 * function. This function fills in frame->data,
3671 * frame->extended_data, frame->linesize[0].
3672 * @param nb_channels channel count
3673 * @param sample_fmt sample format
3674 * @param buf buffer to use for frame data
3675 * @param buf_size size of buffer
3676 * @param align plane size sample alignment (0 = default)
3677 * @return >=0 on success, negative error code on failure
3678 * @todo return the size in bytes required to store the samples in
3679 * case of success, at the next libavutil bump
3681 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
3682 enum AVSampleFormat sample_fmt, const uint8_t *buf,
3683 int buf_size, int align);
3686 * Reset the internal codec state / flush internal buffers. Should be called
3687 * e.g. when seeking or when switching to a different stream.
3689 * @note for decoders, when refcounted frames are not used
3690 * (i.e. avctx->refcounted_frames is 0), this invalidates the frames previously
3691 * returned from the decoder. When refcounted frames are used, the decoder just
3692 * releases any references it might keep internally, but the caller's reference
3695 * @note for encoders, this function will only do something if the encoder
3696 * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3697 * will drain any remaining packets, and can then be re-used for a different
3698 * stream (as opposed to sending a null frame which will leave the encoder
3699 * in a permanent EOF state after draining). This can be desirable if the
3700 * cost of tearing down and replacing the encoder instance is high.
3702 void avcodec_flush_buffers(AVCodecContext *avctx);
3705 * Return codec bits per sample.
3707 * @param[in] codec_id the codec
3708 * @return Number of bits per sample or zero if unknown for the given codec.
3710 int av_get_bits_per_sample(enum AVCodecID codec_id);
3713 * Return the PCM codec associated with a sample format.
3714 * @param be endianness, 0 for little, 1 for big,
3715 * -1 (or anything else) for native
3716 * @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
3718 enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
3721 * Return codec bits per sample.
3722 * Only return non-zero if the bits per sample is exactly correct, not an
3725 * @param[in] codec_id the codec
3726 * @return Number of bits per sample or zero if unknown for the given codec.
3728 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
3731 * Return audio frame duration.
3733 * @param avctx codec context
3734 * @param frame_bytes size of the frame, or 0 if unknown
3735 * @return frame duration, in samples, if known. 0 if not able to
3738 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
3741 * This function is the same as av_get_audio_frame_duration(), except it works
3742 * with AVCodecParameters instead of an AVCodecContext.
3744 int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
3749 * Same behaviour av_fast_malloc but the buffer has additional
3750 * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
3752 * In addition the whole buffer will initially and after resizes
3753 * be 0-initialized so that no uninitialized data will ever appear.
3755 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
3758 * Same behaviour av_fast_padded_malloc except that buffer will always
3759 * be 0-initialized after call.
3761 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
3764 * Encode extradata length to a buffer. Used by xiph codecs.
3766 * @param s buffer to write to; must be at least (v/255+1) bytes long
3767 * @param v size of extradata in bytes
3768 * @return number of bytes written to the buffer.
3770 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
3773 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
3774 * with no corresponding avcodec_close()), 0 otherwise.
3776 int avcodec_is_open(AVCodecContext *s);
3779 * Allocate a CPB properties structure and initialize its fields to default
3782 * @param size if non-NULL, the size of the allocated struct will be written
3783 * here. This is useful for embedding it in side data.
3785 * @return the newly allocated struct or NULL on failure
3787 AVCPBProperties *av_cpb_properties_alloc(size_t *size);
3793 #endif /* AVCODEC_AVCODEC_H */