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"
44 #include "codec_desc.h"
50 * @defgroup libavc libavcodec
51 * Encoding/Decoding Library
55 * @defgroup lavc_decoding Decoding
59 * @defgroup lavc_encoding Encoding
63 * @defgroup lavc_codec Codecs
65 * @defgroup lavc_codec_native Native Codecs
68 * @defgroup lavc_codec_wrappers External library wrappers
71 * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
75 * @defgroup lavc_internal Internal
83 * @defgroup lavc_encdec send/receive encoding and decoding API overview
86 * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
87 * avcodec_receive_packet() functions provide an encode/decode API, which
88 * decouples input and output.
90 * The API is very similar for encoding/decoding and audio/video, and works as
92 * - Set up and open the AVCodecContext as usual.
94 * - For decoding, call avcodec_send_packet() to give the decoder raw
95 * compressed data in an AVPacket.
96 * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
97 * containing uncompressed audio or video.
99 * In both cases, it is recommended that AVPackets and AVFrames are
100 * refcounted, or libavcodec might have to copy the input data. (libavformat
101 * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
102 * refcounted AVFrames.)
103 * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
104 * functions and process their output:
105 * - For decoding, call avcodec_receive_frame(). On success, it will return
106 * an AVFrame containing uncompressed audio or video data.
107 * - For encoding, call avcodec_receive_packet(). On success, it will return
108 * an AVPacket with a compressed frame.
110 * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
111 * AVERROR(EAGAIN) return value means that new input data is required to
112 * return new output. In this case, continue with sending input. For each
113 * input frame/packet, the codec will typically return 1 output frame/packet,
114 * but it can also be 0 or more than 1.
116 * At the beginning of decoding or encoding, the codec might accept multiple
117 * input frames/packets without returning a frame, until its internal buffers
118 * are filled. This situation is handled transparently if you follow the steps
121 * In theory, sending input can result in EAGAIN - this should happen only if
122 * not all output was received. You can use this to structure alternative decode
123 * or encode loops other than the one suggested above. For example, you could
124 * try sending new input on each iteration, and try to receive output if that
127 * End of stream situations. These require "flushing" (aka draining) the codec,
128 * as the codec might buffer multiple frames or packets internally for
129 * performance or out of necessity (consider B-frames).
130 * This is handled as follows:
131 * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
132 * or avcodec_send_frame() (encoding) functions. This will enter draining
134 * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
135 * (encoding) in a loop until AVERROR_EOF is returned. The functions will
136 * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
137 * - Before decoding can be resumed again, the codec has to be reset with
138 * avcodec_flush_buffers().
140 * Using the API as outlined above is highly recommended. But it is also
141 * possible to call functions outside of this rigid schema. For example, you can
142 * call avcodec_send_packet() repeatedly without calling
143 * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
144 * until the codec's internal buffer has been filled up (which is typically of
145 * size 1 per output frame, after initial input), and then reject input with
146 * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
147 * read at least some output.
149 * Not all codecs will follow a rigid and predictable dataflow; the only
150 * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
151 * one end implies that a receive/send call on the other end will succeed, or
152 * at least will not fail with AVERROR(EAGAIN). In general, no codec will
153 * permit unlimited buffering of input or output.
155 * This API replaces the following legacy functions:
156 * - avcodec_decode_video2() and avcodec_decode_audio4():
157 * Use avcodec_send_packet() to feed input to the decoder, then use
158 * avcodec_receive_frame() to receive decoded frames after each packet.
159 * Unlike with the old video decoding API, multiple frames might result from
160 * a packet. For audio, splitting the input packet into frames by partially
161 * decoding packets becomes transparent to the API user. You never need to
162 * feed an AVPacket to the API twice (unless it is rejected with AVERROR(EAGAIN) - then
163 * no data was read from the packet).
164 * Additionally, sending a flush/draining packet is required only once.
165 * - avcodec_encode_video2()/avcodec_encode_audio2():
166 * Use avcodec_send_frame() to feed input to the encoder, then use
167 * avcodec_receive_packet() to receive encoded packets.
168 * Providing user-allocated buffers for avcodec_receive_packet() is not
170 * - The new API does not handle subtitles yet.
172 * Mixing new and old function calls on the same AVCodecContext is not allowed,
173 * and will result in undefined behavior.
175 * Some codecs might require using the new API; using the old API will return
176 * an error when calling it. All codecs support the new API.
178 * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
179 * would be an invalid state, which could put the codec user into an endless
180 * loop. The API has no concept of time either: it cannot happen that trying to
181 * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
182 * later accepts the packet (with no other receive/flush API calls involved).
183 * The API is a strict state machine, and the passage of time is not supposed
184 * to influence it. Some timing-dependent behavior might still be deemed
185 * acceptable in certain cases. But it must never result in both send/receive
186 * returning EAGAIN at the same time at any point. It must also absolutely be
187 * avoided that the current state is "unstable" and can "flip-flop" between
188 * the send/receive APIs allowing progress. For example, it's not allowed that
189 * the codec randomly decides that it actually wants to consume a packet now
190 * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
191 * avcodec_send_packet() call.
196 * @defgroup lavc_core Core functions/structures.
199 * Basic definitions, functions for querying libavcodec capabilities,
200 * allocating core structures, etc.
205 * @ingroup lavc_decoding
206 * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
207 * This is mainly needed because some optimized bitstream readers read
208 * 32 or 64 bit at once and could read over the end.<br>
209 * Note: If the first 23 bits of the additional bytes are not 0, then damaged
210 * MPEG bitstreams could cause overread and segfault.
212 #define AV_INPUT_BUFFER_PADDING_SIZE 64
215 * @ingroup lavc_encoding
216 * minimum encoding buffer size
217 * Used to avoid some checks during header writing.
219 #define AV_INPUT_BUFFER_MIN_SIZE 16384
222 * @ingroup lavc_decoding
225 /* We leave some space between them for extensions (drop some
226 * keyframes for intra-only or drop just some bidir frames). */
227 AVDISCARD_NONE =-16, ///< discard nothing
228 AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
229 AVDISCARD_NONREF = 8, ///< discard all non reference
230 AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
231 AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
232 AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
233 AVDISCARD_ALL = 48, ///< discard all
236 enum AVAudioServiceType {
237 AV_AUDIO_SERVICE_TYPE_MAIN = 0,
238 AV_AUDIO_SERVICE_TYPE_EFFECTS = 1,
239 AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
240 AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED = 3,
241 AV_AUDIO_SERVICE_TYPE_DIALOGUE = 4,
242 AV_AUDIO_SERVICE_TYPE_COMMENTARY = 5,
243 AV_AUDIO_SERVICE_TYPE_EMERGENCY = 6,
244 AV_AUDIO_SERVICE_TYPE_VOICE_OVER = 7,
245 AV_AUDIO_SERVICE_TYPE_KARAOKE = 8,
246 AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
250 * @ingroup lavc_encoding
252 typedef struct RcOverride{
255 int qscale; // If this is 0 then quality_factor will be used instead.
256 float quality_factor;
260 These flags can be passed in AVCodecContext.flags before initialization.
261 Note: Not everything is supported yet.
265 * Allow decoders to produce frames with data planes that are not aligned
266 * to CPU requirements (e.g. due to cropping).
268 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
272 #define AV_CODEC_FLAG_QSCALE (1 << 1)
274 * 4 MV per MB allowed / advanced prediction for H.263.
276 #define AV_CODEC_FLAG_4MV (1 << 2)
278 * Output even those frames that might be corrupted.
280 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
284 #define AV_CODEC_FLAG_QPEL (1 << 4)
286 * Don't output frames whose parameters differ from first
287 * decoded frame in stream.
289 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
291 * Use internal 2pass ratecontrol in first pass mode.
293 #define AV_CODEC_FLAG_PASS1 (1 << 9)
295 * Use internal 2pass ratecontrol in second pass mode.
297 #define AV_CODEC_FLAG_PASS2 (1 << 10)
301 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
303 * Only decode/encode grayscale.
305 #define AV_CODEC_FLAG_GRAY (1 << 13)
307 * error[?] variables will be set during encoding.
309 #define AV_CODEC_FLAG_PSNR (1 << 15)
311 * Input bitstream might be truncated at a random location
312 * instead of only at frame boundaries.
314 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
316 * Use interlaced DCT.
318 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
322 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
324 * Place global headers in extradata instead of every keyframe.
326 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
328 * Use only bitexact stuff (except (I)DCT).
330 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
331 /* Fx : Flag for H.263+ extra options */
333 * H.263 advanced intra coding / MPEG-4 AC prediction
335 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
337 * interlaced motion estimation
339 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
340 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
343 * Allow non spec compliant speedup tricks.
345 #define AV_CODEC_FLAG2_FAST (1 << 0)
347 * Skip bitstream encoding.
349 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
351 * Place global headers at every keyframe instead of in extradata.
353 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
356 * timecode is in drop frame format. DEPRECATED!!!!
358 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
361 * Input bitstream might be truncated at a packet boundaries
362 * instead of only at frame boundaries.
364 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
366 * Discard cropping information from SPS.
368 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
371 * Show all frames before the first keyframe
373 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
375 * Export motion vectors through frame side data
377 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
379 * Do not skip samples and export skip information as frame side data
381 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
383 * Do not reset ASS ReadOrder field on flush (subtitles decoding)
385 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
387 /* Unsupported options :
388 * Syntax Arithmetic coding (SAC)
389 * Reference Picture Selection
390 * Independent Segment Decoding */
392 /* codec capabilities */
395 * Decoder can use draw_horiz_band callback.
397 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
399 * Codec uses get_buffer() for allocating buffers and supports custom allocators.
400 * If not set, it might not use get_buffer() at all or use operations that
401 * assume the buffer was allocated by avcodec_default_get_buffer.
403 #define AV_CODEC_CAP_DR1 (1 << 1)
404 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
406 * Encoder or decoder requires flushing with NULL input at the end in order to
407 * give the complete and correct output.
409 * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
410 * with NULL data. The user can still send NULL data to the public encode
411 * or decode function, but libavcodec will not pass it along to the codec
412 * unless this flag is set.
415 * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
416 * avpkt->size=0 at the end to get the delayed data until the decoder no longer
420 * The encoder needs to be fed with NULL data at the end of encoding until the
421 * encoder no longer returns data.
423 * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
424 * flag also means that the encoder must set the pts and duration for
425 * each output packet. If this flag is not set, the pts and duration will
426 * be determined by libavcodec from the input frame.
428 #define AV_CODEC_CAP_DELAY (1 << 5)
430 * Codec can be fed a final frame with a smaller size.
431 * This can be used to prevent truncation of the last audio samples.
433 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
436 * Codec can output multiple frames per AVPacket
437 * Normally demuxers return one frame at a time, demuxers which do not do
438 * are connected to a parser to split what they return into proper frames.
439 * This flag is reserved to the very rare category of codecs which have a
440 * bitstream that cannot be split into frames without timeconsuming
441 * operations like full decoding. Demuxers carrying such bitstreams thus
442 * may return multiple frames in a packet. This has many disadvantages like
443 * prohibiting stream copy in many cases thus it should only be considered
446 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
448 * Codec is experimental and is thus avoided in favor of non experimental
451 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
453 * Codec should fill in channel configuration and samplerate instead of container
455 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
457 * Codec supports frame-level multithreading.
459 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
461 * Codec supports slice-based (or partition-based) multithreading.
463 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
465 * Codec supports changed parameters at any point.
467 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
469 * Codec supports avctx->thread_count == 0 (auto).
471 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
473 * Audio encoder supports receiving a different number of samples in each call.
475 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
477 * Decoder is not a preferred choice for probing.
478 * This indicates that the decoder is not a good choice for probing.
479 * It could for example be an expensive to spin up hardware decoder,
480 * or it could simply not provide a lot of useful information about
482 * A decoder marked with this flag should only be used as last resort
483 * choice for probing.
485 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
487 * Codec is intra only.
489 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
493 #define AV_CODEC_CAP_LOSSLESS 0x80000000
496 * Codec is backed by a hardware implementation. Typically used to
497 * identify a non-hwaccel hardware decoder. For information about hwaccels, use
498 * avcodec_get_hw_config() instead.
500 #define AV_CODEC_CAP_HARDWARE (1 << 18)
503 * Codec is potentially backed by a hardware implementation, but not
504 * necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
505 * implementation provides some sort of internal fallback.
507 #define AV_CODEC_CAP_HYBRID (1 << 19)
510 * This codec takes the reordered_opaque field from input AVFrames
511 * and returns it in the corresponding field in AVCodecContext after
514 #define AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE (1 << 20)
516 /* Exported side data.
517 These flags can be passed in AVCodecContext.export_side_data before initialization.
520 * Export motion vectors through frame side data
522 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
524 * Export encoder Producer Reference Time through packet side data
526 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
530 * This specifies the area which should be displayed.
531 * Note there may be multiple such areas for one frame.
533 typedef struct AVPanScan {
536 * - encoding: Set by user.
537 * - decoding: Set by libavcodec.
542 * width and height in 1/16 pel
543 * - encoding: Set by user.
544 * - decoding: Set by libavcodec.
550 * position of the top left corner in 1/16 pel for up to 3 fields/frames
551 * - encoding: Set by user.
552 * - decoding: Set by libavcodec.
554 int16_t position[3][2];
558 * This structure describes the bitrate properties of an encoded bitstream. It
559 * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
560 * parameters for H.264/HEVC.
562 typedef struct AVCPBProperties {
564 * Maximum bitrate of the stream, in bits per second.
565 * Zero if unknown or unspecified.
567 #if FF_API_UNSANITIZED_BITRATES
573 * Minimum bitrate of the stream, in bits per second.
574 * Zero if unknown or unspecified.
576 #if FF_API_UNSANITIZED_BITRATES
582 * Average bitrate of the stream, in bits per second.
583 * Zero if unknown or unspecified.
585 #if FF_API_UNSANITIZED_BITRATES
592 * The size of the buffer to which the ratecontrol is applied, in bits.
593 * Zero if unknown or unspecified.
598 * The delay between the time the packet this structure is associated with
599 * is received and the time when it should be decoded, in periods of a 27MHz
602 * UINT64_MAX when unknown or unspecified.
608 * This structure supplies correlation between a packet timestamp and a wall clock
609 * production time. The definition follows the Producer Reference Time ('prft')
610 * as defined in ISO/IEC 14496-12
612 typedef struct AVProducerReferenceTime {
614 * A UTC timestamp, in microseconds, since Unix epoch (e.g, av_gettime()).
618 } AVProducerReferenceTime;
621 * The decoder will keep a reference to the frame and may reuse it later.
623 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
625 struct AVCodecInternal;
629 AV_FIELD_PROGRESSIVE,
630 AV_FIELD_TT, //< Top coded_first, top displayed first
631 AV_FIELD_BB, //< Bottom coded first, bottom displayed first
632 AV_FIELD_TB, //< Top coded first, bottom displayed first
633 AV_FIELD_BT, //< Bottom coded first, top displayed first
637 * main external API structure.
638 * New fields can be added to the end with minor version bumps.
639 * Removal, reordering and changes to existing fields require a major
641 * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
643 * The name string for AVOptions options matches the associated command line
644 * parameter name and can be found in libavcodec/options_table.h
645 * The AVOption/command line parameter names differ in some cases from the C
646 * structure field names for historic reasons or brevity.
647 * sizeof(AVCodecContext) must not be used outside libav*.
649 typedef struct AVCodecContext {
651 * information on struct for av_log
652 * - set by avcodec_alloc_context3
654 const AVClass *av_class;
655 int log_level_offset;
657 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
658 const struct AVCodec *codec;
659 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
662 * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
663 * This is used to work around some encoder bugs.
664 * A demuxer should set this to what is stored in the field used to identify the codec.
665 * If there are multiple such fields in a container then the demuxer should choose the one
666 * which maximizes the information about the used codec.
667 * If the codec tag field in a container is larger than 32 bits then the demuxer should
668 * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
669 * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
671 * - encoding: Set by user, if not then the default based on codec_id will be used.
672 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
674 unsigned int codec_tag;
679 * Private context used for internal data.
681 * Unlike priv_data, this is not codec-specific. It is used in general
682 * libavcodec functions.
684 struct AVCodecInternal *internal;
687 * Private data of the user, can be used to carry app specific stuff.
688 * - encoding: Set by user.
689 * - decoding: Set by user.
694 * the average bitrate
695 * - encoding: Set by user; unused for constant quantizer encoding.
696 * - decoding: Set by user, may be overwritten by libavcodec
697 * if this info is available in the stream
702 * number of bits the bitstream is allowed to diverge from the reference.
703 * the reference can be CBR (for CBR pass1) or VBR (for pass2)
704 * - encoding: Set by user; unused for constant quantizer encoding.
707 int bit_rate_tolerance;
710 * Global quality for codecs which cannot change it per frame.
711 * This should be proportional to MPEG-1/2/4 qscale.
712 * - encoding: Set by user.
718 * - encoding: Set by user.
721 int compression_level;
722 #define FF_COMPRESSION_DEFAULT -1
726 * - encoding: Set by user.
727 * - decoding: Set by user.
733 * - encoding: Set by user.
734 * - decoding: Set by user.
739 * some codecs need / can use extradata like Huffman tables.
740 * MJPEG: Huffman tables
741 * rv10: additional flags
742 * MPEG-4: global headers (they can be in the bitstream or here)
743 * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
744 * than extradata_size to avoid problems if it is read with the bitstream reader.
745 * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
746 * Must be allocated with the av_malloc() family of functions.
747 * - encoding: Set/allocated/freed by libavcodec.
748 * - decoding: Set/allocated/freed by user.
754 * This is the fundamental unit of time (in seconds) in terms
755 * of which frame timestamps are represented. For fixed-fps content,
756 * timebase should be 1/framerate and timestamp increments should be
758 * This often, but not always is the inverse of the frame rate or field rate
759 * for video. 1/time_base is not the average frame rate if the frame rate is not
762 * Like containers, elementary streams also can store timestamps, 1/time_base
763 * is the unit in which these timestamps are specified.
764 * As example of such codec time base see ISO/IEC 14496-2:2001(E)
765 * vop_time_increment_resolution and fixed_vop_rate
766 * (fixed_vop_rate == 0 implies that it is different from the framerate)
768 * - encoding: MUST be set by user.
769 * - decoding: the use of this field for decoding is deprecated.
770 * Use framerate instead.
772 AVRational time_base;
775 * For some codecs, the time base is closer to the field rate than the frame rate.
776 * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
777 * if no telecine is used ...
779 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
786 * Encoding: Number of frames delay there will be from the encoder input to
787 * the decoder output. (we assume the decoder matches the spec)
788 * Decoding: Number of frames delay in addition to what a standard decoder
789 * as specified in the spec would produce.
792 * Number of frames the decoded output will be delayed relative to the
796 * For encoding, this field is unused (see initial_padding).
798 * For decoding, this is the number of samples the decoder needs to
799 * output before the decoder's output is valid. When seeking, you should
800 * start decoding this many samples prior to your desired seek point.
802 * - encoding: Set by libavcodec.
803 * - decoding: Set by libavcodec.
810 * picture width / height.
812 * @note Those fields may not match the values of the last
813 * AVFrame output by avcodec_decode_video2 due frame
816 * - encoding: MUST be set by user.
817 * - decoding: May be set by the user before opening the decoder if known e.g.
818 * from the container. Some decoders will require the dimensions
819 * to be set by the caller. During decoding, the decoder may
820 * overwrite those values as required while parsing the data.
825 * Bitstream width / height, may be different from width/height e.g. when
826 * the decoded frame is cropped before being output or lowres is enabled.
828 * @note Those field may not match the value of the last
829 * AVFrame output by avcodec_receive_frame() due frame
833 * - decoding: May be set by the user before opening the decoder if known
834 * e.g. from the container. During decoding, the decoder may
835 * overwrite those values as required while parsing the data.
837 int coded_width, coded_height;
840 * the number of pictures in a group of pictures, or 0 for intra_only
841 * - encoding: Set by user.
847 * Pixel format, see AV_PIX_FMT_xxx.
848 * May be set by the demuxer if known from headers.
849 * May be overridden by the decoder if it knows better.
851 * @note This field may not match the value of the last
852 * AVFrame output by avcodec_receive_frame() due frame
855 * - encoding: Set by user.
856 * - decoding: Set by user if known, overridden by libavcodec while
859 enum AVPixelFormat pix_fmt;
862 * If non NULL, 'draw_horiz_band' is called by the libavcodec
863 * decoder to draw a horizontal band. It improves cache usage. Not
864 * all codecs can do that. You must check the codec capabilities
866 * When multithreading is used, it may be called from multiple threads
867 * at the same time; threads might draw different parts of the same AVFrame,
868 * or multiple AVFrames, and there is no guarantee that slices will be drawn
870 * The function is also used by hardware acceleration APIs.
871 * It is called at least once during frame decoding to pass
872 * the data needed for hardware render.
873 * In that mode instead of pixel data, AVFrame points to
874 * a structure specific to the acceleration API. The application
875 * reads the structure and can change some fields to indicate progress
878 * - decoding: Set by user.
879 * @param height the height of the slice
880 * @param y the y position of the slice
881 * @param type 1->top field, 2->bottom field, 3->frame
882 * @param offset offset into the AVFrame.data from which the slice should be read
884 void (*draw_horiz_band)(struct AVCodecContext *s,
885 const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
886 int y, int type, int height);
889 * callback to negotiate the pixelFormat
890 * @param fmt is the list of formats which are supported by the codec,
891 * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
892 * The first is always the native one.
893 * @note The callback may be called again immediately if initialization for
894 * the selected (hardware-accelerated) pixel format failed.
895 * @warning Behavior is undefined if the callback returns a value not
896 * in the fmt list of formats.
897 * @return the chosen format
899 * - decoding: Set by user, if not set the native format will be chosen.
901 enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
904 * maximum number of B-frames between non-B-frames
905 * Note: The output will be delayed by max_b_frames+1 relative to the input.
906 * - encoding: Set by user.
912 * qscale factor between IP and B-frames
913 * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
914 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
915 * - encoding: Set by user.
918 float b_quant_factor;
920 #if FF_API_PRIVATE_OPT
921 /** @deprecated use encoder private options instead */
923 int b_frame_strategy;
927 * qscale offset between IP and B-frames
928 * - encoding: Set by user.
931 float b_quant_offset;
934 * Size of the frame reordering buffer in the decoder.
935 * For MPEG-2 it is 1 IPB or 0 low delay IP.
936 * - encoding: Set by libavcodec.
937 * - decoding: Set by libavcodec.
941 #if FF_API_PRIVATE_OPT
942 /** @deprecated use encoder private options instead */
948 * qscale factor between P- and I-frames
949 * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
950 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
951 * - encoding: Set by user.
954 float i_quant_factor;
957 * qscale offset between P and I-frames
958 * - encoding: Set by user.
961 float i_quant_offset;
964 * luminance masking (0-> disabled)
965 * - encoding: Set by user.
971 * temporary complexity masking (0-> disabled)
972 * - encoding: Set by user.
975 float temporal_cplx_masking;
978 * spatial complexity masking (0-> disabled)
979 * - encoding: Set by user.
982 float spatial_cplx_masking;
985 * p block masking (0-> disabled)
986 * - encoding: Set by user.
992 * darkness masking (0-> disabled)
993 * - encoding: Set by user.
1000 * - encoding: Set by libavcodec.
1001 * - decoding: Set by user (or 0).
1005 #if FF_API_PRIVATE_OPT
1006 /** @deprecated use encoder private options instead */
1007 attribute_deprecated
1008 int prediction_method;
1009 #define FF_PRED_LEFT 0
1010 #define FF_PRED_PLANE 1
1011 #define FF_PRED_MEDIAN 2
1015 * slice offsets in the frame in bytes
1016 * - encoding: Set/allocated by libavcodec.
1017 * - decoding: Set/allocated by user (or NULL).
1022 * sample aspect ratio (0 if unknown)
1023 * That is the width of a pixel divided by the height of the pixel.
1024 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1025 * - encoding: Set by user.
1026 * - decoding: Set by libavcodec.
1028 AVRational sample_aspect_ratio;
1031 * motion estimation comparison function
1032 * - encoding: Set by user.
1033 * - decoding: unused
1037 * subpixel motion estimation comparison function
1038 * - encoding: Set by user.
1039 * - decoding: unused
1043 * macroblock comparison function (not supported yet)
1044 * - encoding: Set by user.
1045 * - decoding: unused
1049 * interlaced DCT comparison function
1050 * - encoding: Set by user.
1051 * - decoding: unused
1054 #define FF_CMP_SAD 0
1055 #define FF_CMP_SSE 1
1056 #define FF_CMP_SATD 2
1057 #define FF_CMP_DCT 3
1058 #define FF_CMP_PSNR 4
1059 #define FF_CMP_BIT 5
1061 #define FF_CMP_ZERO 7
1062 #define FF_CMP_VSAD 8
1063 #define FF_CMP_VSSE 9
1064 #define FF_CMP_NSSE 10
1065 #define FF_CMP_W53 11
1066 #define FF_CMP_W97 12
1067 #define FF_CMP_DCTMAX 13
1068 #define FF_CMP_DCT264 14
1069 #define FF_CMP_MEDIAN_SAD 15
1070 #define FF_CMP_CHROMA 256
1073 * ME diamond size & shape
1074 * - encoding: Set by user.
1075 * - decoding: unused
1080 * amount of previous MV predictors (2a+1 x 2a+1 square)
1081 * - encoding: Set by user.
1082 * - decoding: unused
1084 int last_predictor_count;
1086 #if FF_API_PRIVATE_OPT
1087 /** @deprecated use encoder private options instead */
1088 attribute_deprecated
1093 * motion estimation prepass comparison function
1094 * - encoding: Set by user.
1095 * - decoding: unused
1100 * ME prepass diamond size & shape
1101 * - encoding: Set by user.
1102 * - decoding: unused
1108 * - encoding: Set by user.
1109 * - decoding: unused
1111 int me_subpel_quality;
1114 * maximum motion estimation search range in subpel units
1115 * If 0 then no limit.
1117 * - encoding: Set by user.
1118 * - decoding: unused
1124 * - encoding: unused
1125 * - decoding: Set by user.
1128 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1129 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
1130 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1133 * macroblock decision mode
1134 * - encoding: Set by user.
1135 * - decoding: unused
1138 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1139 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1140 #define FF_MB_DECISION_RD 2 ///< rate distortion
1143 * custom intra quantization matrix
1144 * Must be allocated with the av_malloc() family of functions, and will be freed in
1145 * avcodec_free_context().
1146 * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
1147 * - decoding: Set/allocated/freed by libavcodec.
1149 uint16_t *intra_matrix;
1152 * custom inter quantization matrix
1153 * Must be allocated with the av_malloc() family of functions, and will be freed in
1154 * avcodec_free_context().
1155 * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
1156 * - decoding: Set/allocated/freed by libavcodec.
1158 uint16_t *inter_matrix;
1160 #if FF_API_PRIVATE_OPT
1161 /** @deprecated use encoder private options instead */
1162 attribute_deprecated
1163 int scenechange_threshold;
1165 /** @deprecated use encoder private options instead */
1166 attribute_deprecated
1167 int noise_reduction;
1171 * precision of the intra DC coefficient - 8
1172 * - encoding: Set by user.
1173 * - decoding: Set by libavcodec
1175 int intra_dc_precision;
1178 * Number of macroblock rows at the top which are skipped.
1179 * - encoding: unused
1180 * - decoding: Set by user.
1185 * Number of macroblock rows at the bottom which are skipped.
1186 * - encoding: unused
1187 * - decoding: Set by user.
1192 * minimum MB Lagrange multiplier
1193 * - encoding: Set by user.
1194 * - decoding: unused
1199 * maximum MB Lagrange multiplier
1200 * - encoding: Set by user.
1201 * - decoding: unused
1205 #if FF_API_PRIVATE_OPT
1207 * @deprecated use encoder private options instead
1209 attribute_deprecated
1210 int me_penalty_compensation;
1214 * - encoding: Set by user.
1215 * - decoding: unused
1219 #if FF_API_PRIVATE_OPT
1220 /** @deprecated use encoder private options instead */
1221 attribute_deprecated
1227 * - encoding: Set by user.
1228 * - decoding: unused
1233 * number of reference frames
1234 * - encoding: Set by user.
1235 * - decoding: Set by lavc.
1239 #if FF_API_PRIVATE_OPT
1240 /** @deprecated use encoder private options instead */
1241 attribute_deprecated
1246 * Note: Value depends upon the compare function used for fullpel ME.
1247 * - encoding: Set by user.
1248 * - decoding: unused
1252 #if FF_API_PRIVATE_OPT
1253 /** @deprecated use encoder private options instead */
1254 attribute_deprecated
1259 * Chromaticity coordinates of the source primaries.
1260 * - encoding: Set by user
1261 * - decoding: Set by libavcodec
1263 enum AVColorPrimaries color_primaries;
1266 * Color Transfer Characteristic.
1267 * - encoding: Set by user
1268 * - decoding: Set by libavcodec
1270 enum AVColorTransferCharacteristic color_trc;
1273 * YUV colorspace type.
1274 * - encoding: Set by user
1275 * - decoding: Set by libavcodec
1277 enum AVColorSpace colorspace;
1280 * MPEG vs JPEG YUV range.
1281 * - encoding: Set by user
1282 * - decoding: Set by libavcodec
1284 enum AVColorRange color_range;
1287 * This defines the location of chroma samples.
1288 * - encoding: Set by user
1289 * - decoding: Set by libavcodec
1291 enum AVChromaLocation chroma_sample_location;
1295 * Indicates number of picture subdivisions. Used for parallelized
1297 * - encoding: Set by user
1298 * - decoding: unused
1303 * - encoding: set by libavcodec
1304 * - decoding: Set by user.
1306 enum AVFieldOrder field_order;
1309 int sample_rate; ///< samples per second
1310 int channels; ///< number of audio channels
1313 * audio sample format
1314 * - encoding: Set by user.
1315 * - decoding: Set by libavcodec.
1317 enum AVSampleFormat sample_fmt; ///< sample format
1319 /* The following data should not be initialized. */
1321 * Number of samples per channel in an audio frame.
1323 * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1324 * except the last must contain exactly frame_size samples per channel.
1325 * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1326 * frame size is not restricted.
1327 * - decoding: may be set by some decoders to indicate constant frame size
1332 * Frame counter, set by libavcodec.
1334 * - decoding: total number of frames returned from the decoder so far.
1335 * - encoding: total number of frames passed to the encoder so far.
1337 * @note the counter is not incremented if encoding/decoding resulted in
1343 * number of bytes per packet if constant and known or 0
1344 * Used by some WAV based audio codecs.
1349 * Audio cutoff bandwidth (0 means "automatic")
1350 * - encoding: Set by user.
1351 * - decoding: unused
1356 * Audio channel layout.
1357 * - encoding: set by user.
1358 * - decoding: set by user, may be overwritten by libavcodec.
1360 uint64_t channel_layout;
1363 * Request decoder to use this channel layout if it can (0 for default)
1364 * - encoding: unused
1365 * - decoding: Set by user.
1367 uint64_t request_channel_layout;
1370 * Type of service that the audio stream conveys.
1371 * - encoding: Set by user.
1372 * - decoding: Set by libavcodec.
1374 enum AVAudioServiceType audio_service_type;
1377 * desired sample format
1378 * - encoding: Not used.
1379 * - decoding: Set by user.
1380 * Decoder will decode to this format if it can.
1382 enum AVSampleFormat request_sample_fmt;
1385 * This callback is called at the beginning of each frame to get data
1386 * buffer(s) for it. There may be one contiguous buffer for all the data or
1387 * there may be a buffer per each data plane or anything in between. What
1388 * this means is, you may set however many entries in buf[] you feel necessary.
1389 * Each buffer must be reference-counted using the AVBuffer API (see description
1392 * The following fields will be set in the frame before this callback is
1395 * - width, height (video only)
1396 * - sample_rate, channel_layout, nb_samples (audio only)
1397 * Their values may differ from the corresponding values in
1398 * AVCodecContext. This callback must use the frame values, not the codec
1399 * context values, to calculate the required buffer size.
1401 * This callback must fill the following fields in the frame:
1405 * * if the data is planar audio with more than 8 channels, then this
1406 * callback must allocate and fill extended_data to contain all pointers
1407 * to all data planes. data[] must hold as many pointers as it can.
1408 * extended_data must be allocated with av_malloc() and will be freed in
1410 * * otherwise extended_data must point to data
1411 * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1412 * the frame's data and extended_data pointers must be contained in these. That
1413 * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1414 * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1415 * and av_buffer_ref().
1416 * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1417 * this callback and filled with the extra buffers if there are more
1418 * buffers than buf[] can hold. extended_buf will be freed in
1421 * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1422 * avcodec_default_get_buffer2() instead of providing buffers allocated by
1425 * Each data plane must be aligned to the maximum required by the target
1428 * @see avcodec_default_get_buffer2()
1432 * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1433 * (read and/or written to if it is writable) later by libavcodec.
1435 * avcodec_align_dimensions2() should be used to find the required width and
1436 * height, as they normally need to be rounded up to the next multiple of 16.
1438 * Some decoders do not support linesizes changing between frames.
1440 * If frame multithreading is used and thread_safe_callbacks is set,
1441 * this callback may be called from a different thread, but not from more
1442 * than one at once. Does not need to be reentrant.
1444 * @see avcodec_align_dimensions2()
1448 * Decoders request a buffer of a particular size by setting
1449 * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1450 * however, utilize only part of the buffer by setting AVFrame.nb_samples
1451 * to a smaller value in the output frame.
1453 * As a convenience, av_samples_get_buffer_size() and
1454 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1455 * functions to find the required data size and to fill data pointers and
1456 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1457 * since all planes must be the same size.
1459 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1461 * - encoding: unused
1462 * - decoding: Set by libavcodec, user can override.
1464 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
1467 * If non-zero, the decoded audio and video frames returned from
1468 * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
1469 * and are valid indefinitely. The caller must free them with
1470 * av_frame_unref() when they are not needed anymore.
1471 * Otherwise, the decoded frames must not be freed by the caller and are
1472 * only valid until the next decode call.
1474 * This is always automatically enabled if avcodec_receive_frame() is used.
1476 * - encoding: unused
1477 * - decoding: set by the caller before avcodec_open2().
1479 attribute_deprecated
1480 int refcounted_frames;
1482 /* - encoding parameters */
1483 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1484 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1488 * - encoding: Set by user.
1489 * - decoding: unused
1495 * - encoding: Set by user.
1496 * - decoding: unused
1501 * maximum quantizer difference between frames
1502 * - encoding: Set by user.
1503 * - decoding: unused
1508 * decoder bitstream buffer size
1509 * - encoding: Set by user.
1510 * - decoding: unused
1515 * ratecontrol override, see RcOverride
1516 * - encoding: Allocated/set/freed by user.
1517 * - decoding: unused
1519 int rc_override_count;
1520 RcOverride *rc_override;
1524 * - encoding: Set by user.
1525 * - decoding: Set by user, may be overwritten by libavcodec.
1527 int64_t rc_max_rate;
1531 * - encoding: Set by user.
1532 * - decoding: unused
1534 int64_t rc_min_rate;
1537 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1538 * - encoding: Set by user.
1539 * - decoding: unused.
1541 float rc_max_available_vbv_use;
1544 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1545 * - encoding: Set by user.
1546 * - decoding: unused.
1548 float rc_min_vbv_overflow_use;
1551 * Number of bits which should be loaded into the rc buffer before decoding starts.
1552 * - encoding: Set by user.
1553 * - decoding: unused
1555 int rc_initial_buffer_occupancy;
1557 #if FF_API_CODER_TYPE
1558 #define FF_CODER_TYPE_VLC 0
1559 #define FF_CODER_TYPE_AC 1
1560 #define FF_CODER_TYPE_RAW 2
1561 #define FF_CODER_TYPE_RLE 3
1563 * @deprecated use encoder private options instead
1565 attribute_deprecated
1567 #endif /* FF_API_CODER_TYPE */
1569 #if FF_API_PRIVATE_OPT
1570 /** @deprecated use encoder private options instead */
1571 attribute_deprecated
1575 #if FF_API_PRIVATE_OPT
1576 /** @deprecated use encoder private options instead */
1577 attribute_deprecated
1578 int frame_skip_threshold;
1580 /** @deprecated use encoder private options instead */
1581 attribute_deprecated
1582 int frame_skip_factor;
1584 /** @deprecated use encoder private options instead */
1585 attribute_deprecated
1588 /** @deprecated use encoder private options instead */
1589 attribute_deprecated
1591 #endif /* FF_API_PRIVATE_OPT */
1594 * trellis RD quantization
1595 * - encoding: Set by user.
1596 * - decoding: unused
1600 #if FF_API_PRIVATE_OPT
1601 /** @deprecated use encoder private options instead */
1602 attribute_deprecated
1603 int min_prediction_order;
1605 /** @deprecated use encoder private options instead */
1606 attribute_deprecated
1607 int max_prediction_order;
1609 /** @deprecated use encoder private options instead */
1610 attribute_deprecated
1611 int64_t timecode_frame_start;
1614 #if FF_API_RTP_CALLBACK
1616 * @deprecated unused
1618 /* The RTP callback: This function is called */
1619 /* every time the encoder has a packet to send. */
1620 /* It depends on the encoder if the data starts */
1621 /* with a Start Code (it should). H.263 does. */
1622 /* mb_nb contains the number of macroblocks */
1623 /* encoded in the RTP payload. */
1624 attribute_deprecated
1625 void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
1628 #if FF_API_PRIVATE_OPT
1629 /** @deprecated use encoder private options instead */
1630 attribute_deprecated
1631 int rtp_payload_size; /* The size of the RTP payload: the coder will */
1632 /* do its best to deliver a chunk with size */
1633 /* below rtp_payload_size, the chunk will start */
1634 /* with a start code on some codecs like H.263. */
1635 /* This doesn't take account of any particular */
1636 /* headers inside the transmitted RTP payload. */
1639 #if FF_API_STAT_BITS
1640 /* statistics, used for 2-pass encoding */
1641 attribute_deprecated
1643 attribute_deprecated
1645 attribute_deprecated
1647 attribute_deprecated
1649 attribute_deprecated
1651 attribute_deprecated
1653 attribute_deprecated
1655 attribute_deprecated
1658 /** @deprecated this field is unused */
1659 attribute_deprecated
1664 * pass1 encoding statistics output buffer
1665 * - encoding: Set by libavcodec.
1666 * - decoding: unused
1671 * pass2 encoding statistics input buffer
1672 * Concatenated stuff from stats_out of pass1 should be placed here.
1673 * - encoding: Allocated/set/freed by user.
1674 * - decoding: unused
1679 * Work around bugs in encoders which sometimes cannot be detected automatically.
1680 * - encoding: Set by user
1681 * - decoding: Set by user
1683 int workaround_bugs;
1684 #define FF_BUG_AUTODETECT 1 ///< autodetection
1685 #define FF_BUG_XVID_ILACE 4
1686 #define FF_BUG_UMP4 8
1687 #define FF_BUG_NO_PADDING 16
1688 #define FF_BUG_AMV 32
1689 #define FF_BUG_QPEL_CHROMA 64
1690 #define FF_BUG_STD_QPEL 128
1691 #define FF_BUG_QPEL_CHROMA2 256
1692 #define FF_BUG_DIRECT_BLOCKSIZE 512
1693 #define FF_BUG_EDGE 1024
1694 #define FF_BUG_HPEL_CHROMA 2048
1695 #define FF_BUG_DC_CLIP 4096
1696 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1697 #define FF_BUG_TRUNCATED 16384
1698 #define FF_BUG_IEDGE 32768
1701 * strictly follow the standard (MPEG-4, ...).
1702 * - encoding: Set by user.
1703 * - decoding: Set by user.
1704 * Setting this to STRICT or higher means the encoder and decoder will
1705 * generally do stupid things, whereas setting it to unofficial or lower
1706 * will mean the encoder might produce output that is not supported by all
1707 * spec-compliant decoders. Decoders don't differentiate between normal,
1708 * unofficial and experimental (that is, they always try to decode things
1709 * when they can) unless they are explicitly asked to behave stupidly
1710 * (=strictly conform to the specs)
1712 int strict_std_compliance;
1713 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
1714 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
1715 #define FF_COMPLIANCE_NORMAL 0
1716 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
1717 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
1720 * error concealment flags
1721 * - encoding: unused
1722 * - decoding: Set by user.
1724 int error_concealment;
1725 #define FF_EC_GUESS_MVS 1
1726 #define FF_EC_DEBLOCK 2
1727 #define FF_EC_FAVOR_INTER 256
1731 * - encoding: Set by user.
1732 * - decoding: Set by user.
1735 #define FF_DEBUG_PICT_INFO 1
1736 #define FF_DEBUG_RC 2
1737 #define FF_DEBUG_BITSTREAM 4
1738 #define FF_DEBUG_MB_TYPE 8
1739 #define FF_DEBUG_QP 16
1742 * @deprecated this option does nothing
1744 #define FF_DEBUG_MV 32
1746 #define FF_DEBUG_DCT_COEFF 0x00000040
1747 #define FF_DEBUG_SKIP 0x00000080
1748 #define FF_DEBUG_STARTCODE 0x00000100
1749 #define FF_DEBUG_ER 0x00000400
1750 #define FF_DEBUG_MMCO 0x00000800
1751 #define FF_DEBUG_BUGS 0x00001000
1753 #define FF_DEBUG_VIS_QP 0x00002000
1754 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
1756 #define FF_DEBUG_BUFFERS 0x00008000
1757 #define FF_DEBUG_THREADS 0x00010000
1758 #define FF_DEBUG_GREEN_MD 0x00800000
1759 #define FF_DEBUG_NOMC 0x01000000
1764 * - encoding: Set by user.
1765 * - decoding: Set by user.
1768 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
1769 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
1770 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
1774 * Error recognition; may misdetect some more or less valid parts as errors.
1775 * - encoding: unused
1776 * - decoding: Set by user.
1778 int err_recognition;
1781 * Verify checksums embedded in the bitstream (could be of either encoded or
1782 * decoded data, depending on the codec) and print an error message on mismatch.
1783 * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
1784 * decoder returning an error.
1786 #define AV_EF_CRCCHECK (1<<0)
1787 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
1788 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
1789 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
1791 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
1792 #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
1793 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
1794 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
1798 * opaque 64-bit number (generally a PTS) that will be reordered and
1799 * output in AVFrame.reordered_opaque
1800 * - encoding: Set by libavcodec to the reordered_opaque of the input
1801 * frame corresponding to the last returned packet. Only
1802 * supported by encoders with the
1803 * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1804 * - decoding: Set by user.
1806 int64_t reordered_opaque;
1809 * Hardware accelerator in use
1810 * - encoding: unused.
1811 * - decoding: Set by libavcodec
1813 const struct AVHWAccel *hwaccel;
1816 * Hardware accelerator context.
1817 * For some hardware accelerators, a global context needs to be
1818 * provided by the user. In that case, this holds display-dependent
1819 * data FFmpeg cannot instantiate itself. Please refer to the
1820 * FFmpeg HW accelerator documentation to know how to fill this
1821 * is. e.g. for VA API, this is a struct vaapi_context.
1822 * - encoding: unused
1823 * - decoding: Set by user
1825 void *hwaccel_context;
1829 * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1830 * - decoding: unused
1832 uint64_t error[AV_NUM_DATA_POINTERS];
1835 * DCT algorithm, see FF_DCT_* below
1836 * - encoding: Set by user.
1837 * - decoding: unused
1840 #define FF_DCT_AUTO 0
1841 #define FF_DCT_FASTINT 1
1842 #define FF_DCT_INT 2
1843 #define FF_DCT_MMX 3
1844 #define FF_DCT_ALTIVEC 5
1845 #define FF_DCT_FAAN 6
1848 * IDCT algorithm, see FF_IDCT_* below.
1849 * - encoding: Set by user.
1850 * - decoding: Set by user.
1853 #define FF_IDCT_AUTO 0
1854 #define FF_IDCT_INT 1
1855 #define FF_IDCT_SIMPLE 2
1856 #define FF_IDCT_SIMPLEMMX 3
1857 #define FF_IDCT_ARM 7
1858 #define FF_IDCT_ALTIVEC 8
1859 #define FF_IDCT_SIMPLEARM 10
1860 #define FF_IDCT_XVID 14
1861 #define FF_IDCT_SIMPLEARMV5TE 16
1862 #define FF_IDCT_SIMPLEARMV6 17
1863 #define FF_IDCT_FAAN 20
1864 #define FF_IDCT_SIMPLENEON 22
1865 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
1866 #define FF_IDCT_SIMPLEAUTO 128
1869 * bits per sample/pixel from the demuxer (needed for huffyuv).
1870 * - encoding: Set by libavcodec.
1871 * - decoding: Set by user.
1873 int bits_per_coded_sample;
1876 * Bits per sample/pixel of internal libavcodec pixel/sample format.
1877 * - encoding: set by user.
1878 * - decoding: set by libavcodec.
1880 int bits_per_raw_sample;
1884 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1885 * - encoding: unused
1886 * - decoding: Set by user.
1891 #if FF_API_CODED_FRAME
1893 * the picture in the bitstream
1894 * - encoding: Set by libavcodec.
1895 * - decoding: unused
1897 * @deprecated use the quality factor packet side data instead
1899 attribute_deprecated AVFrame *coded_frame;
1904 * is used to decide how many independent tasks should be passed to execute()
1905 * - encoding: Set by user.
1906 * - decoding: Set by user.
1911 * Which multithreading methods to use.
1912 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1913 * so clients which cannot provide future frames should not use it.
1915 * - encoding: Set by user, otherwise the default is used.
1916 * - decoding: Set by user, otherwise the default is used.
1919 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1920 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1923 * Which multithreading methods are in use by the codec.
1924 * - encoding: Set by libavcodec.
1925 * - decoding: Set by libavcodec.
1927 int active_thread_type;
1930 * Set by the client if its custom get_buffer() callback can be called
1931 * synchronously from another thread, which allows faster multithreaded decoding.
1932 * draw_horiz_band() will be called from other threads regardless of this setting.
1933 * Ignored if the default get_buffer() is used.
1934 * - encoding: Set by user.
1935 * - decoding: Set by user.
1937 int thread_safe_callbacks;
1940 * The codec may call this to execute several independent things.
1941 * It will return only after finishing all tasks.
1942 * The user may replace this with some multithreaded implementation,
1943 * the default implementation will execute the parts serially.
1944 * @param count the number of things to execute
1945 * - encoding: Set by libavcodec, user can override.
1946 * - decoding: Set by libavcodec, user can override.
1948 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1951 * The codec may call this to execute several independent things.
1952 * It will return only after finishing all tasks.
1953 * The user may replace this with some multithreaded implementation,
1954 * the default implementation will execute the parts serially.
1955 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
1956 * @param c context passed also to func
1957 * @param count the number of things to execute
1958 * @param arg2 argument passed unchanged to func
1959 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1960 * @param func function that will be called count times, with jobnr from 0 to count-1.
1961 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1962 * two instances of func executing at the same time will have the same threadnr.
1963 * @return always 0 currently, but code should handle a future improvement where when any call to func
1964 * returns < 0 no further calls to func may be done and < 0 is returned.
1965 * - encoding: Set by libavcodec, user can override.
1966 * - decoding: Set by libavcodec, user can override.
1968 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1971 * noise vs. sse weight for the nsse comparison function
1972 * - encoding: Set by user.
1973 * - decoding: unused
1979 * - encoding: Set by user.
1980 * - decoding: Set by libavcodec.
1983 #define FF_PROFILE_UNKNOWN -99
1984 #define FF_PROFILE_RESERVED -100
1986 #define FF_PROFILE_AAC_MAIN 0
1987 #define FF_PROFILE_AAC_LOW 1
1988 #define FF_PROFILE_AAC_SSR 2
1989 #define FF_PROFILE_AAC_LTP 3
1990 #define FF_PROFILE_AAC_HE 4
1991 #define FF_PROFILE_AAC_HE_V2 28
1992 #define FF_PROFILE_AAC_LD 22
1993 #define FF_PROFILE_AAC_ELD 38
1994 #define FF_PROFILE_MPEG2_AAC_LOW 128
1995 #define FF_PROFILE_MPEG2_AAC_HE 131
1997 #define FF_PROFILE_DNXHD 0
1998 #define FF_PROFILE_DNXHR_LB 1
1999 #define FF_PROFILE_DNXHR_SQ 2
2000 #define FF_PROFILE_DNXHR_HQ 3
2001 #define FF_PROFILE_DNXHR_HQX 4
2002 #define FF_PROFILE_DNXHR_444 5
2004 #define FF_PROFILE_DTS 20
2005 #define FF_PROFILE_DTS_ES 30
2006 #define FF_PROFILE_DTS_96_24 40
2007 #define FF_PROFILE_DTS_HD_HRA 50
2008 #define FF_PROFILE_DTS_HD_MA 60
2009 #define FF_PROFILE_DTS_EXPRESS 70
2011 #define FF_PROFILE_MPEG2_422 0
2012 #define FF_PROFILE_MPEG2_HIGH 1
2013 #define FF_PROFILE_MPEG2_SS 2
2014 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2015 #define FF_PROFILE_MPEG2_MAIN 4
2016 #define FF_PROFILE_MPEG2_SIMPLE 5
2018 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2019 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2021 #define FF_PROFILE_H264_BASELINE 66
2022 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2023 #define FF_PROFILE_H264_MAIN 77
2024 #define FF_PROFILE_H264_EXTENDED 88
2025 #define FF_PROFILE_H264_HIGH 100
2026 #define FF_PROFILE_H264_HIGH_10 110
2027 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2028 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
2029 #define FF_PROFILE_H264_HIGH_422 122
2030 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2031 #define FF_PROFILE_H264_STEREO_HIGH 128
2032 #define FF_PROFILE_H264_HIGH_444 144
2033 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2034 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2035 #define FF_PROFILE_H264_CAVLC_444 44
2037 #define FF_PROFILE_VC1_SIMPLE 0
2038 #define FF_PROFILE_VC1_MAIN 1
2039 #define FF_PROFILE_VC1_COMPLEX 2
2040 #define FF_PROFILE_VC1_ADVANCED 3
2042 #define FF_PROFILE_MPEG4_SIMPLE 0
2043 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2044 #define FF_PROFILE_MPEG4_CORE 2
2045 #define FF_PROFILE_MPEG4_MAIN 3
2046 #define FF_PROFILE_MPEG4_N_BIT 4
2047 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2048 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2049 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2050 #define FF_PROFILE_MPEG4_HYBRID 8
2051 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2052 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2053 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2054 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2055 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2056 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2057 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2059 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
2060 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
2061 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
2062 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2063 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2065 #define FF_PROFILE_VP9_0 0
2066 #define FF_PROFILE_VP9_1 1
2067 #define FF_PROFILE_VP9_2 2
2068 #define FF_PROFILE_VP9_3 3
2070 #define FF_PROFILE_HEVC_MAIN 1
2071 #define FF_PROFILE_HEVC_MAIN_10 2
2072 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2073 #define FF_PROFILE_HEVC_REXT 4
2075 #define FF_PROFILE_AV1_MAIN 0
2076 #define FF_PROFILE_AV1_HIGH 1
2077 #define FF_PROFILE_AV1_PROFESSIONAL 2
2079 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
2080 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
2081 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
2082 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
2083 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
2085 #define FF_PROFILE_SBC_MSBC 1
2087 #define FF_PROFILE_PRORES_PROXY 0
2088 #define FF_PROFILE_PRORES_LT 1
2089 #define FF_PROFILE_PRORES_STANDARD 2
2090 #define FF_PROFILE_PRORES_HQ 3
2091 #define FF_PROFILE_PRORES_4444 4
2092 #define FF_PROFILE_PRORES_XQ 5
2094 #define FF_PROFILE_ARIB_PROFILE_A 0
2095 #define FF_PROFILE_ARIB_PROFILE_C 1
2099 * - encoding: Set by user.
2100 * - decoding: Set by libavcodec.
2103 #define FF_LEVEL_UNKNOWN -99
2106 * Skip loop filtering for selected frames.
2107 * - encoding: unused
2108 * - decoding: Set by user.
2110 enum AVDiscard skip_loop_filter;
2113 * Skip IDCT/dequantization for selected frames.
2114 * - encoding: unused
2115 * - decoding: Set by user.
2117 enum AVDiscard skip_idct;
2120 * Skip decoding for selected frames.
2121 * - encoding: unused
2122 * - decoding: Set by user.
2124 enum AVDiscard skip_frame;
2127 * Header containing style information for text subtitles.
2128 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2129 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2130 * the Format line following. It shouldn't include any Dialogue line.
2131 * - encoding: Set/allocated/freed by user (before avcodec_open2())
2132 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2134 uint8_t *subtitle_header;
2135 int subtitle_header_size;
2137 #if FF_API_VBV_DELAY
2139 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2140 * Used for compliant TS muxing.
2141 * - encoding: Set by libavcodec.
2142 * - decoding: unused.
2143 * @deprecated this value is now exported as a part of
2144 * AV_PKT_DATA_CPB_PROPERTIES packet side data
2146 attribute_deprecated
2150 #if FF_API_SIDEDATA_ONLY_PKT
2152 * Encoding only and set by default. Allow encoders to output packets
2153 * that do not contain any encoded data, only side data.
2155 * Some encoders need to output such packets, e.g. to update some stream
2156 * parameters at the end of encoding.
2158 * @deprecated this field disables the default behaviour and
2159 * it is kept only for compatibility.
2161 attribute_deprecated
2162 int side_data_only_packets;
2166 * Audio only. The number of "priming" samples (padding) inserted by the
2167 * encoder at the beginning of the audio. I.e. this number of leading
2168 * decoded samples must be discarded by the caller to get the original audio
2169 * without leading padding.
2171 * - decoding: unused
2172 * - encoding: Set by libavcodec. The timestamps on the output packets are
2173 * adjusted by the encoder so that they always refer to the
2174 * first sample of the data actually contained in the packet,
2175 * including any added padding. E.g. if the timebase is
2176 * 1/samplerate and the timestamp of the first input sample is
2177 * 0, the timestamp of the first output packet will be
2180 int initial_padding;
2183 * - decoding: For codecs that store a framerate value in the compressed
2184 * bitstream, the decoder may export it here. { 0, 1} when
2186 * - encoding: May be used to signal the framerate of CFR content to an
2189 AVRational framerate;
2192 * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
2193 * - encoding: unused.
2194 * - decoding: Set by libavcodec before calling get_format()
2196 enum AVPixelFormat sw_pix_fmt;
2199 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
2200 * - encoding unused.
2201 * - decoding set by user.
2203 AVRational pkt_timebase;
2207 * - encoding: unused.
2208 * - decoding: set by libavcodec.
2210 const AVCodecDescriptor *codec_descriptor;
2214 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2215 * - encoding: unused
2216 * - decoding: Set by user.
2222 * Current statistics for PTS correction.
2223 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
2224 * - encoding: unused
2226 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
2227 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
2228 int64_t pts_correction_last_pts; /// PTS of the last frame
2229 int64_t pts_correction_last_dts; /// DTS of the last frame
2232 * Character encoding of the input subtitles file.
2233 * - decoding: set by user
2234 * - encoding: unused
2239 * Subtitles character encoding mode. Formats or codecs might be adjusting
2240 * this setting (if they are doing the conversion themselves for instance).
2241 * - decoding: set by libavcodec
2242 * - encoding: unused
2244 int sub_charenc_mode;
2245 #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)
2246 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
2247 #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
2248 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
2251 * Skip processing alpha if supported by codec.
2252 * Note that if the format uses pre-multiplied alpha (common with VP6,
2253 * and recommended due to better video quality/compression)
2254 * the image will look as if alpha-blended onto a black background.
2255 * However for formats that do not use pre-multiplied alpha
2256 * there might be serious artefacts (though e.g. libswscale currently
2257 * assumes pre-multiplied alpha anyway).
2259 * - decoding: set by user
2260 * - encoding: unused
2265 * Number of samples to skip after a discontinuity
2266 * - decoding: unused
2267 * - encoding: set by libavcodec
2271 #if !FF_API_DEBUG_MV
2273 * debug motion vectors
2274 * - encoding: Set by user.
2275 * - decoding: Set by user.
2278 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
2279 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
2280 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2284 * custom intra quantization matrix
2285 * - encoding: Set by user, can be NULL.
2286 * - decoding: unused.
2288 uint16_t *chroma_intra_matrix;
2291 * dump format separator.
2292 * can be ", " or "\n " or anything else
2293 * - encoding: Set by user.
2294 * - decoding: Set by user.
2296 uint8_t *dump_separator;
2299 * ',' separated list of allowed decoders.
2300 * If NULL then all are allowed
2301 * - encoding: unused
2302 * - decoding: set by user
2304 char *codec_whitelist;
2307 * Properties of the stream that gets decoded
2308 * - encoding: unused
2309 * - decoding: set by libavcodec
2311 unsigned properties;
2312 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
2313 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
2316 * Additional data associated with the entire coded stream.
2318 * - decoding: unused
2319 * - encoding: may be set by libavcodec after avcodec_open2().
2321 AVPacketSideData *coded_side_data;
2322 int nb_coded_side_data;
2325 * A reference to the AVHWFramesContext describing the input (for encoding)
2326 * or output (decoding) frames. The reference is set by the caller and
2327 * afterwards owned (and freed) by libavcodec - it should never be read by
2328 * the caller after being set.
2330 * - decoding: This field should be set by the caller from the get_format()
2331 * callback. The previous reference (if any) will always be
2332 * unreffed by libavcodec before the get_format() call.
2334 * If the default get_buffer2() is used with a hwaccel pixel
2335 * format, then this AVHWFramesContext will be used for
2336 * allocating the frame buffers.
2338 * - encoding: For hardware encoders configured to use a hwaccel pixel
2339 * format, this field should be set by the caller to a reference
2340 * to the AVHWFramesContext describing input frames.
2341 * AVHWFramesContext.format must be equal to
2342 * AVCodecContext.pix_fmt.
2344 * This field should be set before avcodec_open2() is called.
2346 AVBufferRef *hw_frames_ctx;
2349 * Control the form of AVSubtitle.rects[N]->ass
2350 * - decoding: set by user
2351 * - encoding: unused
2353 int sub_text_format;
2354 #define FF_SUB_TEXT_FMT_ASS 0
2355 #if FF_API_ASS_TIMING
2356 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
2360 * Audio only. The amount of padding (in samples) appended by the encoder to
2361 * the end of the audio. I.e. this number of decoded samples must be
2362 * discarded by the caller from the end of the stream to get the original
2363 * audio without any trailing padding.
2365 * - decoding: unused
2366 * - encoding: unused
2368 int trailing_padding;
2371 * The number of pixels per image to maximally accept.
2373 * - decoding: set by user
2374 * - encoding: set by user
2379 * A reference to the AVHWDeviceContext describing the device which will
2380 * be used by a hardware encoder/decoder. The reference is set by the
2381 * caller and afterwards owned (and freed) by libavcodec.
2383 * This should be used if either the codec device does not require
2384 * hardware frames or any that are used are to be allocated internally by
2385 * libavcodec. If the user wishes to supply any of the frames used as
2386 * encoder input or decoder output then hw_frames_ctx should be used
2387 * instead. When hw_frames_ctx is set in get_format() for a decoder, this
2388 * field will be ignored while decoding the associated stream segment, but
2389 * may again be used on a following one after another get_format() call.
2391 * For both encoders and decoders this field should be set before
2392 * avcodec_open2() is called and must not be written to thereafter.
2394 * Note that some decoders may require this field to be set initially in
2395 * order to support hw_frames_ctx at all - in that case, all frames
2396 * contexts used must be created on the same device.
2398 AVBufferRef *hw_device_ctx;
2401 * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
2402 * decoding (if active).
2403 * - encoding: unused
2404 * - decoding: Set by user (either before avcodec_open2(), or in the
2405 * AVCodecContext.get_format callback)
2410 * Video decoding only. Certain video codecs support cropping, meaning that
2411 * only a sub-rectangle of the decoded frame is intended for display. This
2412 * option controls how cropping is handled by libavcodec.
2414 * When set to 1 (the default), libavcodec will apply cropping internally.
2415 * I.e. it will modify the output frame width/height fields and offset the
2416 * data pointers (only by as much as possible while preserving alignment, or
2417 * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
2418 * the frames output by the decoder refer only to the cropped area. The
2419 * crop_* fields of the output frames will be zero.
2421 * When set to 0, the width/height fields of the output frames will be set
2422 * to the coded dimensions and the crop_* fields will describe the cropping
2423 * rectangle. Applying the cropping is left to the caller.
2425 * @warning When hardware acceleration with opaque output frames is used,
2426 * libavcodec is unable to apply cropping from the top/left border.
2428 * @note when this option is set to zero, the width/height fields of the
2429 * AVCodecContext and output AVFrames have different meanings. The codec
2430 * context fields store display dimensions (with the coded dimensions in
2431 * coded_width/height), while the frame fields store the coded dimensions
2432 * (with the display dimensions being determined by the crop_* fields).
2437 * Video decoding only. Sets the number of extra hardware frames which
2438 * the decoder will allocate for use by the caller. This must be set
2439 * before avcodec_open2() is called.
2441 * Some hardware decoders require all frames that they will use for
2442 * output to be defined in advance before decoding starts. For such
2443 * decoders, the hardware frame pool must therefore be of a fixed size.
2444 * The extra frames set here are on top of any number that the decoder
2445 * needs internally in order to operate normally (for example, frames
2446 * used as reference pictures).
2448 int extra_hw_frames;
2451 * The percentage of damaged samples to discard a frame.
2453 * - decoding: set by user
2454 * - encoding: unused
2456 int discard_damaged_percentage;
2459 * The number of samples per frame to maximally accept.
2461 * - decoding: set by user
2462 * - encoding: set by user
2464 int64_t max_samples;
2467 * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
2468 * metadata exported in frame, packet, or coded stream side data by
2469 * decoders and encoders.
2471 * - decoding: set by user
2472 * - encoding: set by user
2474 int export_side_data;
2477 #if FF_API_CODEC_GET_SET
2479 * Accessors for some AVCodecContext fields. These used to be provided for ABI
2480 * compatibility, and do not need to be used anymore.
2482 attribute_deprecated
2483 AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
2484 attribute_deprecated
2485 void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
2487 attribute_deprecated
2488 const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
2489 attribute_deprecated
2490 void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
2492 attribute_deprecated
2493 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
2496 attribute_deprecated
2497 int av_codec_get_lowres(const AVCodecContext *avctx);
2498 attribute_deprecated
2499 void av_codec_set_lowres(AVCodecContext *avctx, int val);
2502 attribute_deprecated
2503 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
2504 attribute_deprecated
2505 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
2507 attribute_deprecated
2508 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
2509 attribute_deprecated
2510 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
2516 typedef struct AVProfile {
2518 const char *name; ///< short name for the profile
2523 * The codec supports this format via the hw_device_ctx interface.
2525 * When selecting this format, AVCodecContext.hw_device_ctx should
2526 * have been set to a device of the specified type before calling
2529 AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX = 0x01,
2531 * The codec supports this format via the hw_frames_ctx interface.
2533 * When selecting this format for a decoder,
2534 * AVCodecContext.hw_frames_ctx should be set to a suitable frames
2535 * context inside the get_format() callback. The frames context
2536 * must have been created on a device of the specified type.
2538 AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX = 0x02,
2540 * The codec supports this format by some internal method.
2542 * This format can be selected without any additional configuration -
2543 * no device or frames context is required.
2545 AV_CODEC_HW_CONFIG_METHOD_INTERNAL = 0x04,
2547 * The codec supports this format by some ad-hoc method.
2549 * Additional settings and/or function calls are required. See the
2550 * codec-specific documentation for details. (Methods requiring
2551 * this sort of configuration are deprecated and others should be
2552 * used in preference.)
2554 AV_CODEC_HW_CONFIG_METHOD_AD_HOC = 0x08,
2557 typedef struct AVCodecHWConfig {
2559 * A hardware pixel format which the codec can use.
2561 enum AVPixelFormat pix_fmt;
2563 * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
2564 * setup methods which can be used with this configuration.
2568 * The device type associated with the configuration.
2570 * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
2571 * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
2573 enum AVHWDeviceType device_type;
2576 typedef struct AVCodecDefault AVCodecDefault;
2583 typedef struct AVCodec {
2585 * Name of the codec implementation.
2586 * The name is globally unique among encoders and among decoders (but an
2587 * encoder and a decoder can share the same name).
2588 * This is the primary way to find a codec from the user perspective.
2592 * Descriptive name for the codec, meant to be more human readable than name.
2593 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
2595 const char *long_name;
2596 enum AVMediaType type;
2599 * Codec capabilities.
2600 * see AV_CODEC_CAP_*
2603 const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
2604 const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
2605 const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
2606 const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
2607 const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
2608 uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
2609 const AVClass *priv_class; ///< AVClass for the private context
2610 const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
2613 * Group name of the codec implementation.
2614 * This is a short symbolic name of the wrapper backing this codec. A
2615 * wrapper uses some kind of external implementation for the codec, such
2616 * as an external library, or a codec implementation provided by the OS or
2618 * If this field is NULL, this is a builtin, libavcodec native codec.
2619 * If non-NULL, this will be the suffix in AVCodec.name in most cases
2620 * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
2622 const char *wrapper_name;
2624 /*****************************************************************
2625 * No fields below this line are part of the public API. They
2626 * may not be used outside of libavcodec and can be changed and
2628 * New public fields should be added right above.
2629 *****************************************************************
2632 struct AVCodec *next;
2634 * @name Frame-level threading support functions
2638 * If defined, called on thread contexts when they are created.
2639 * If the codec allocates writable tables in init(), re-allocate them here.
2640 * priv_data will be set to a copy of the original.
2642 int (*init_thread_copy)(AVCodecContext *);
2644 * Copy necessary context variables from a previous thread context to the current one.
2645 * If not defined, the next thread will start automatically; otherwise, the codec
2646 * must call ff_thread_finish_setup().
2648 * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
2650 int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
2654 * Private codec-specific defaults.
2656 const AVCodecDefault *defaults;
2659 * Initialize codec static data, called from avcodec_register().
2661 * This is not intended for time consuming operations as it is
2662 * run for every codec regardless of that codec being used.
2664 void (*init_static_data)(struct AVCodec *codec);
2666 int (*init)(AVCodecContext *);
2667 int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
2668 const struct AVSubtitle *sub);
2670 * Encode data to an AVPacket.
2672 * @param avctx codec context
2673 * @param avpkt output AVPacket (may contain a user-provided buffer)
2674 * @param[in] frame AVFrame containing the raw data to be encoded
2675 * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
2676 * non-empty packet was returned in avpkt.
2677 * @return 0 on success, negative error code on failure
2679 int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
2680 int *got_packet_ptr);
2681 int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
2682 int (*close)(AVCodecContext *);
2684 * Encode API with decoupled packet/frame dataflow. The API is the
2685 * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
2687 * - never called if the codec is closed or the wrong type,
2688 * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
2689 * - only one drain frame is ever passed down,
2691 int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
2692 int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
2695 * Decode API with decoupled packet/frame dataflow. This function is called
2696 * to get one output frame. It should call ff_decode_get_packet() to obtain
2699 int (*receive_frame)(AVCodecContext *avctx, AVFrame *frame);
2702 * Will be called when seeking
2704 void (*flush)(AVCodecContext *);
2706 * Internal codec capabilities.
2707 * See FF_CODEC_CAP_* in internal.h
2712 * Decoding only, a comma-separated list of bitstream filters to apply to
2713 * packets before decoding.
2718 * Array of pointers to hardware configurations supported by the codec,
2719 * or NULL if no hardware supported. The array is terminated by a NULL
2722 * The user can only access this field via avcodec_get_hw_config().
2724 const struct AVCodecHWConfigInternal **hw_configs;
2727 * List of supported codec_tags, terminated by FF_CODEC_TAGS_END.
2729 const uint32_t *codec_tags;
2732 #if FF_API_CODEC_GET_SET
2733 attribute_deprecated
2734 int av_codec_get_max_lowres(const AVCodec *codec);
2737 struct MpegEncContext;
2740 * Retrieve supported hardware configurations for a codec.
2742 * Values of index from zero to some maximum return the indexed configuration
2743 * descriptor; all other values return NULL. If the codec does not support
2744 * any hardware configurations then it will always return NULL.
2746 const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
2749 * @defgroup lavc_hwaccel AVHWAccel
2751 * @note Nothing in this structure should be accessed by the user. At some
2752 * point in future it will not be externally visible at all.
2756 typedef struct AVHWAccel {
2758 * Name of the hardware accelerated codec.
2759 * The name is globally unique among encoders and among decoders (but an
2760 * encoder and a decoder can share the same name).
2765 * Type of codec implemented by the hardware accelerator.
2767 * See AVMEDIA_TYPE_xxx
2769 enum AVMediaType type;
2772 * Codec implemented by the hardware accelerator.
2774 * See AV_CODEC_ID_xxx
2779 * Supported pixel format.
2781 * Only hardware accelerated formats are supported here.
2783 enum AVPixelFormat pix_fmt;
2786 * Hardware accelerated codec capabilities.
2787 * see AV_HWACCEL_CODEC_CAP_*
2791 /*****************************************************************
2792 * No fields below this line are part of the public API. They
2793 * may not be used outside of libavcodec and can be changed and
2795 * New public fields should be added right above.
2796 *****************************************************************
2800 * Allocate a custom buffer
2802 int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
2805 * Called at the beginning of each frame or field picture.
2807 * Meaningful frame information (codec specific) is guaranteed to
2808 * be parsed at this point. This function is mandatory.
2810 * Note that buf can be NULL along with buf_size set to 0.
2811 * Otherwise, this means the whole frame is available at this point.
2813 * @param avctx the codec context
2814 * @param buf the frame data buffer base
2815 * @param buf_size the size of the frame in bytes
2816 * @return zero if successful, a negative value otherwise
2818 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2821 * Callback for parameter data (SPS/PPS/VPS etc).
2823 * Useful for hardware decoders which keep persistent state about the
2824 * video parameters, and need to receive any changes to update that state.
2826 * @param avctx the codec context
2827 * @param type the nal unit type
2828 * @param buf the nal unit data buffer
2829 * @param buf_size the size of the nal unit in bytes
2830 * @return zero if successful, a negative value otherwise
2832 int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
2835 * Callback for each slice.
2837 * Meaningful slice information (codec specific) is guaranteed to
2838 * be parsed at this point. This function is mandatory.
2839 * The only exception is XvMC, that works on MB level.
2841 * @param avctx the codec context
2842 * @param buf the slice data buffer base
2843 * @param buf_size the size of the slice in bytes
2844 * @return zero if successful, a negative value otherwise
2846 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2849 * Called at the end of each frame or field picture.
2851 * The whole picture is parsed at this point and can now be sent
2852 * to the hardware accelerator. This function is mandatory.
2854 * @param avctx the codec context
2855 * @return zero if successful, a negative value otherwise
2857 int (*end_frame)(AVCodecContext *avctx);
2860 * Size of per-frame hardware accelerator private data.
2862 * Private data is allocated with av_mallocz() before
2863 * AVCodecContext.get_buffer() and deallocated after
2864 * AVCodecContext.release_buffer().
2866 int frame_priv_data_size;
2869 * Called for every Macroblock in a slice.
2871 * XvMC uses it to replace the ff_mpv_reconstruct_mb().
2872 * Instead of decoding to raw picture, MB parameters are
2873 * stored in an array provided by the video driver.
2875 * @param s the mpeg context
2877 void (*decode_mb)(struct MpegEncContext *s);
2880 * Initialize the hwaccel private data.
2882 * This will be called from ff_get_format(), after hwaccel and
2883 * hwaccel_context are set and the hwaccel private data in AVCodecInternal
2886 int (*init)(AVCodecContext *avctx);
2889 * Uninitialize the hwaccel private data.
2891 * This will be called from get_format() or avcodec_close(), after hwaccel
2892 * and hwaccel_context are already uninitialized.
2894 int (*uninit)(AVCodecContext *avctx);
2897 * Size of the private data to allocate in
2898 * AVCodecInternal.hwaccel_priv_data.
2903 * Internal hwaccel capabilities.
2908 * Fill the given hw_frames context with current codec parameters. Called
2909 * from get_format. Refer to avcodec_get_hw_frames_parameters() for
2912 * This CAN be called before AVHWAccel.init is called, and you must assume
2913 * that avctx->hwaccel_priv_data is invalid.
2915 int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
2919 * HWAccel is experimental and is thus avoided in favor of non experimental
2922 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2925 * Hardware acceleration should be used for decoding even if the codec level
2926 * used is unknown or higher than the maximum supported level reported by the
2929 * It's generally a good idea to pass this flag unless you have a specific
2930 * reason not to, as hardware tends to under-report supported levels.
2932 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2935 * Hardware acceleration can output YUV pixel formats with a different chroma
2936 * sampling than 4:2:0 and/or other than 8 bits per component.
2938 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2941 * Hardware acceleration should still be attempted for decoding when the
2942 * codec profile does not match the reported capabilities of the hardware.
2944 * For example, this can be used to try to decode baseline profile H.264
2945 * streams in hardware - it will often succeed, because many streams marked
2946 * as baseline profile actually conform to constrained baseline profile.
2948 * @warning If the stream is actually not supported then the behaviour is
2949 * undefined, and may include returning entirely incorrect output
2950 * while indicating success.
2952 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2958 #if FF_API_AVPICTURE
2960 * @defgroup lavc_picture AVPicture
2962 * Functions for working with AVPicture
2967 * Picture data structure.
2969 * Up to four components can be stored into it, the last component is
2971 * @deprecated use AVFrame or imgutils functions instead
2973 typedef struct AVPicture {
2974 attribute_deprecated
2975 uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
2976 attribute_deprecated
2977 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
2985 enum AVSubtitleType {
2988 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2991 * Plain text, the text field must be set by the decoder and is
2992 * authoritative. ass and pict fields may contain approximations.
2997 * Formatted text, the ass field must be set by the decoder and is
2998 * authoritative. pict and text fields may contain approximations.
3003 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3005 typedef struct AVSubtitleRect {
3006 int x; ///< top left corner of pict, undefined when pict is not set
3007 int y; ///< top left corner of pict, undefined when pict is not set
3008 int w; ///< width of pict, undefined when pict is not set
3009 int h; ///< height of pict, undefined when pict is not set
3010 int nb_colors; ///< number of colors in pict, undefined when pict is not set
3012 #if FF_API_AVPICTURE
3014 * @deprecated unused
3016 attribute_deprecated
3020 * data+linesize for the bitmap of this subtitle.
3021 * Can be set for text/ass as well once they are rendered.
3026 enum AVSubtitleType type;
3028 char *text; ///< 0 terminated plain UTF-8 text
3031 * 0 terminated ASS/SSA compatible event line.
3032 * The presentation of this is unaffected by the other values in this
3040 typedef struct AVSubtitle {
3041 uint16_t format; /* 0 = graphics */
3042 uint32_t start_display_time; /* relative to packet pts, in ms */
3043 uint32_t end_display_time; /* relative to packet pts, in ms */
3045 AVSubtitleRect **rects;
3046 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3050 * This struct describes the properties of an encoded stream.
3052 * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3053 * be allocated with avcodec_parameters_alloc() and freed with
3054 * avcodec_parameters_free().
3056 typedef struct AVCodecParameters {
3058 * General type of the encoded data.
3060 enum AVMediaType codec_type;
3062 * Specific type of the encoded data (the codec used).
3064 enum AVCodecID codec_id;
3066 * Additional information about the codec (corresponds to the AVI FOURCC).
3071 * Extra binary data needed for initializing the decoder, codec-dependent.
3073 * Must be allocated with av_malloc() and will be freed by
3074 * avcodec_parameters_free(). The allocated size of extradata must be at
3075 * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3080 * Size of the extradata content in bytes.
3085 * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3086 * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3091 * The average bitrate of the encoded data (in bits per second).
3096 * The number of bits per sample in the codedwords.
3098 * This is basically the bitrate per sample. It is mandatory for a bunch of
3099 * formats to actually decode them. It's the number of bits for one sample in
3100 * the actual coded bitstream.
3102 * This could be for example 4 for ADPCM
3103 * For PCM formats this matches bits_per_raw_sample
3106 int bits_per_coded_sample;
3109 * This is the number of valid bits in each output sample. If the
3110 * sample format has more bits, the least significant bits are additional
3111 * padding bits, which are always 0. Use right shifts to reduce the sample
3112 * to its actual size. For example, audio formats with 24 bit samples will
3113 * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
3114 * To get the original sample use "(int32_t)sample >> 8"."
3116 * For ADPCM this might be 12 or 16 or similar
3119 int bits_per_raw_sample;
3122 * Codec-specific bitstream restrictions that the stream conforms to.
3128 * Video only. The dimensions of the video frame in pixels.
3134 * Video only. The aspect ratio (width / height) which a single pixel
3135 * should have when displayed.
3137 * When the aspect ratio is unknown / undefined, the numerator should be
3138 * set to 0 (the denominator may have any value).
3140 AVRational sample_aspect_ratio;
3143 * Video only. The order of the fields in interlaced video.
3145 enum AVFieldOrder field_order;
3148 * Video only. Additional colorspace characteristics.
3150 enum AVColorRange color_range;
3151 enum AVColorPrimaries color_primaries;
3152 enum AVColorTransferCharacteristic color_trc;
3153 enum AVColorSpace color_space;
3154 enum AVChromaLocation chroma_location;
3157 * Video only. Number of delayed frames.
3162 * Audio only. The channel layout bitmask. May be 0 if the channel layout is
3163 * unknown or unspecified, otherwise the number of bits set must be equal to
3164 * the channels field.
3166 uint64_t channel_layout;
3168 * Audio only. The number of audio channels.
3172 * Audio only. The number of audio samples per second.
3176 * Audio only. The number of bytes per coded audio frame, required by some
3179 * Corresponds to nBlockAlign in WAVEFORMATEX.
3183 * Audio only. Audio frame size, if known. Required by some formats to be static.
3188 * Audio only. The amount of padding (in samples) inserted by the encoder at
3189 * the beginning of the audio. I.e. this number of leading decoded samples
3190 * must be discarded by the caller to get the original audio without leading
3193 int initial_padding;
3195 * Audio only. The amount of padding (in samples) appended by the encoder to
3196 * the end of the audio. I.e. this number of decoded samples must be
3197 * discarded by the caller from the end of the stream to get the original
3198 * audio without any trailing padding.
3200 int trailing_padding;
3202 * Audio only. Number of samples to skip after a discontinuity.
3205 } AVCodecParameters;
3208 * Iterate over all registered codecs.
3210 * @param opaque a pointer where libavcodec will store the iteration state. Must
3211 * point to NULL to start the iteration.
3213 * @return the next registered codec or NULL when the iteration is
3216 const AVCodec *av_codec_iterate(void **opaque);
3220 * If c is NULL, returns the first registered codec,
3221 * if c is non-NULL, returns the next registered codec after c,
3222 * or NULL if c is the last one.
3224 attribute_deprecated
3225 AVCodec *av_codec_next(const AVCodec *c);
3229 * Return the LIBAVCODEC_VERSION_INT constant.
3231 unsigned avcodec_version(void);
3234 * Return the libavcodec build-time configuration.
3236 const char *avcodec_configuration(void);
3239 * Return the libavcodec license.
3241 const char *avcodec_license(void);
3245 * Register the codec codec and initialize libavcodec.
3247 * @warning either this function or avcodec_register_all() must be called
3248 * before any other libavcodec functions.
3250 * @see avcodec_register_all()
3252 attribute_deprecated
3253 void avcodec_register(AVCodec *codec);
3256 * Register all the codecs, parsers and bitstream filters which were enabled at
3257 * configuration time. If you do not call this function you can select exactly
3258 * which formats you want to support, by using the individual registration
3261 * @see avcodec_register
3262 * @see av_register_codec_parser
3263 * @see av_register_bitstream_filter
3265 attribute_deprecated
3266 void avcodec_register_all(void);
3270 * Allocate an AVCodecContext and set its fields to default values. The
3271 * resulting struct should be freed with avcodec_free_context().
3273 * @param codec if non-NULL, allocate private data and initialize defaults
3274 * for the given codec. It is illegal to then call avcodec_open2()
3275 * with a different codec.
3276 * If NULL, then the codec-specific defaults won't be initialized,
3277 * which may result in suboptimal default settings (this is
3278 * important mainly for encoders, e.g. libx264).
3280 * @return An AVCodecContext filled with default values or NULL on failure.
3282 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
3285 * Free the codec context and everything associated with it and write NULL to
3286 * the provided pointer.
3288 void avcodec_free_context(AVCodecContext **avctx);
3290 #if FF_API_GET_CONTEXT_DEFAULTS
3292 * @deprecated This function should not be used, as closing and opening a codec
3293 * context multiple time is not supported. A new codec context should be
3294 * allocated for each new use.
3296 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
3300 * Get the AVClass for AVCodecContext. It can be used in combination with
3301 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3303 * @see av_opt_find().
3305 const AVClass *avcodec_get_class(void);
3307 #if FF_API_COPY_CONTEXT
3309 * Get the AVClass for AVFrame. It can be used in combination with
3310 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3312 * @see av_opt_find().
3314 const AVClass *avcodec_get_frame_class(void);
3317 * Get the AVClass for AVSubtitleRect. It can be used in combination with
3318 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3320 * @see av_opt_find().
3322 const AVClass *avcodec_get_subtitle_rect_class(void);
3325 * Copy the settings of the source AVCodecContext into the destination
3326 * AVCodecContext. The resulting destination codec context will be
3327 * unopened, i.e. you are required to call avcodec_open2() before you
3328 * can use this AVCodecContext to decode/encode video/audio data.
3330 * @param dest target codec context, should be initialized with
3331 * avcodec_alloc_context3(NULL), but otherwise uninitialized
3332 * @param src source codec context
3333 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
3335 * @deprecated The semantics of this function are ill-defined and it should not
3336 * be used. If you need to transfer the stream parameters from one codec context
3337 * to another, use an intermediate AVCodecParameters instance and the
3338 * avcodec_parameters_from_context() / avcodec_parameters_to_context()
3341 attribute_deprecated
3342 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
3346 * Allocate a new AVCodecParameters and set its fields to default values
3347 * (unknown/invalid/0). The returned struct must be freed with
3348 * avcodec_parameters_free().
3350 AVCodecParameters *avcodec_parameters_alloc(void);
3353 * Free an AVCodecParameters instance and everything associated with it and
3354 * write NULL to the supplied pointer.
3356 void avcodec_parameters_free(AVCodecParameters **par);
3359 * Copy the contents of src to dst. Any allocated fields in dst are freed and
3360 * replaced with newly allocated duplicates of the corresponding fields in src.
3362 * @return >= 0 on success, a negative AVERROR code on failure.
3364 int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src);
3367 * Fill the parameters struct based on the values from the supplied codec
3368 * context. Any allocated fields in par are freed and replaced with duplicates
3369 * of the corresponding fields in codec.
3371 * @return >= 0 on success, a negative AVERROR code on failure
3373 int avcodec_parameters_from_context(AVCodecParameters *par,
3374 const AVCodecContext *codec);
3377 * Fill the codec context based on the values from the supplied codec
3378 * parameters. Any allocated fields in codec that have a corresponding field in
3379 * par are freed and replaced with duplicates of the corresponding field in par.
3380 * Fields in codec that do not have a counterpart in par are not touched.
3382 * @return >= 0 on success, a negative AVERROR code on failure.
3384 int avcodec_parameters_to_context(AVCodecContext *codec,
3385 const AVCodecParameters *par);
3388 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
3389 * function the context has to be allocated with avcodec_alloc_context3().
3391 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
3392 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
3393 * retrieving a codec.
3395 * @warning This function is not thread safe!
3397 * @note Always call this function before using decoding routines (such as
3398 * @ref avcodec_receive_frame()).
3401 * avcodec_register_all();
3402 * av_dict_set(&opts, "b", "2.5M", 0);
3403 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
3407 * context = avcodec_alloc_context3(codec);
3409 * if (avcodec_open2(context, codec, opts) < 0)
3413 * @param avctx The context to initialize.
3414 * @param codec The codec to open this context for. If a non-NULL codec has been
3415 * previously passed to avcodec_alloc_context3() or
3416 * for this context, then this parameter MUST be either NULL or
3417 * equal to the previously passed codec.
3418 * @param options A dictionary filled with AVCodecContext and codec-private options.
3419 * On return this object will be filled with options that were not found.
3421 * @return zero on success, a negative value on error
3422 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
3423 * av_dict_set(), av_opt_find().
3425 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
3428 * Close a given AVCodecContext and free all the data associated with it
3429 * (but not the AVCodecContext itself).
3431 * Calling this function on an AVCodecContext that hasn't been opened will free
3432 * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
3433 * codec. Subsequent calls will do nothing.
3435 * @note Do not use this function. Use avcodec_free_context() to destroy a
3436 * codec context (either open or closed). Opening and closing a codec context
3437 * multiple times is not supported anymore -- use multiple codec contexts
3440 int avcodec_close(AVCodecContext *avctx);
3443 * Free all allocated data in the given subtitle struct.
3445 * @param sub AVSubtitle to free.
3447 void avsubtitle_free(AVSubtitle *sub);
3454 * @addtogroup lavc_decoding
3459 * Find a registered decoder with a matching codec ID.
3461 * @param id AVCodecID of the requested decoder
3462 * @return A decoder if one was found, NULL otherwise.
3464 AVCodec *avcodec_find_decoder(enum AVCodecID id);
3467 * Find a registered decoder with the specified name.
3469 * @param name name of the requested decoder
3470 * @return A decoder if one was found, NULL otherwise.
3472 AVCodec *avcodec_find_decoder_by_name(const char *name);
3475 * The default callback for AVCodecContext.get_buffer2(). It is made public so
3476 * it can be called by custom get_buffer2() implementations for decoders without
3477 * AV_CODEC_CAP_DR1 set.
3479 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
3482 * Modify width and height values so that they will result in a memory
3483 * buffer that is acceptable for the codec if you do not use any horizontal
3486 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
3488 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
3491 * Modify width and height values so that they will result in a memory
3492 * buffer that is acceptable for the codec if you also ensure that all
3493 * line sizes are a multiple of the respective linesize_align[i].
3495 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
3497 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
3498 int linesize_align[AV_NUM_DATA_POINTERS]);
3501 * Converts AVChromaLocation to swscale x/y chroma position.
3503 * The positions represent the chroma (0,0) position in a coordinates system
3504 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3506 * @param xpos horizontal chroma sample position
3507 * @param ypos vertical chroma sample position
3509 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
3512 * Converts swscale x/y chroma position to AVChromaLocation.
3514 * The positions represent the chroma (0,0) position in a coordinates system
3515 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3517 * @param xpos horizontal chroma sample position
3518 * @param ypos vertical chroma sample position
3520 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
3523 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
3525 * Some decoders may support multiple frames in a single AVPacket. Such
3526 * decoders would then just decode the first frame and the return value would be
3527 * less than the packet size. In this case, avcodec_decode_audio4 has to be
3528 * called again with an AVPacket containing the remaining data in order to
3529 * decode the second frame, etc... Even if no frames are returned, the packet
3530 * needs to be fed to the decoder with remaining data until it is completely
3531 * consumed or an error occurs.
3533 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
3534 * and output. This means that for some packets they will not immediately
3535 * produce decoded output and need to be flushed at the end of decoding to get
3536 * all the decoded data. Flushing is done by calling this function with packets
3537 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3538 * returning samples. It is safe to flush even those decoders that are not
3539 * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
3541 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
3542 * larger than the actual read bytes because some optimized bitstream
3543 * readers read 32 or 64 bits at once and could read over the end.
3545 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3546 * before packets may be fed to the decoder.
3548 * @param avctx the codec context
3549 * @param[out] frame The AVFrame in which to store decoded audio samples.
3550 * The decoder will allocate a buffer for the decoded frame by
3551 * calling the AVCodecContext.get_buffer2() callback.
3552 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3553 * reference counted and the returned reference belongs to the
3554 * caller. The caller must release the frame using av_frame_unref()
3555 * when the frame is no longer needed. The caller may safely write
3556 * to the frame if av_frame_is_writable() returns 1.
3557 * When AVCodecContext.refcounted_frames is set to 0, the returned
3558 * reference belongs to the decoder and is valid only until the
3559 * next call to this function or until closing or flushing the
3560 * decoder. The caller may not write to it.
3561 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
3562 * non-zero. Note that this field being set to zero
3563 * does not mean that an error has occurred. For
3564 * decoders with AV_CODEC_CAP_DELAY set, no given decode
3565 * call is guaranteed to produce a frame.
3566 * @param[in] avpkt The input AVPacket containing the input buffer.
3567 * At least avpkt->data and avpkt->size should be set. Some
3568 * decoders might also require additional fields to be set.
3569 * @return A negative error code is returned if an error occurred during
3570 * decoding, otherwise the number of bytes consumed from the input
3571 * AVPacket is returned.
3573 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
3575 attribute_deprecated
3576 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
3577 int *got_frame_ptr, const AVPacket *avpkt);
3580 * Decode the video frame of size avpkt->size from avpkt->data into picture.
3581 * Some decoders may support multiple frames in a single AVPacket, such
3582 * decoders would then just decode the first frame.
3584 * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
3585 * the actual read bytes because some optimized bitstream readers read 32 or 64
3586 * bits at once and could read over the end.
3588 * @warning The end of the input buffer buf should be set to 0 to ensure that
3589 * no overreading happens for damaged MPEG streams.
3591 * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
3592 * between input and output, these need to be fed with avpkt->data=NULL,
3593 * avpkt->size=0 at the end to return the remaining frames.
3595 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3596 * before packets may be fed to the decoder.
3598 * @param avctx the codec context
3599 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
3600 * Use av_frame_alloc() to get an AVFrame. The codec will
3601 * allocate memory for the actual bitmap by calling the
3602 * AVCodecContext.get_buffer2() callback.
3603 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3604 * reference counted and the returned reference belongs to the
3605 * caller. The caller must release the frame using av_frame_unref()
3606 * when the frame is no longer needed. The caller may safely write
3607 * to the frame if av_frame_is_writable() returns 1.
3608 * When AVCodecContext.refcounted_frames is set to 0, the returned
3609 * reference belongs to the decoder and is valid only until the
3610 * next call to this function or until closing or flushing the
3611 * decoder. The caller may not write to it.
3613 * @param[in] avpkt The input AVPacket containing the input buffer.
3614 * You can create such packet with av_init_packet() and by then setting
3615 * data and size, some decoders might in addition need other fields like
3616 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
3618 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
3619 * @return On error a negative value is returned, otherwise the number of bytes
3620 * used or zero if no frame could be decompressed.
3622 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
3624 attribute_deprecated
3625 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
3626 int *got_picture_ptr,
3627 const AVPacket *avpkt);
3630 * Decode a subtitle message.
3631 * Return a negative value on error, otherwise return the number of bytes used.
3632 * If no subtitle could be decompressed, got_sub_ptr is zero.
3633 * Otherwise, the subtitle is stored in *sub.
3634 * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
3635 * simplicity, because the performance difference is expected to be negligible
3636 * and reusing a get_buffer written for video codecs would probably perform badly
3637 * due to a potentially very different allocation pattern.
3639 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
3640 * and output. This means that for some packets they will not immediately
3641 * produce decoded output and need to be flushed at the end of decoding to get
3642 * all the decoded data. Flushing is done by calling this function with packets
3643 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3644 * returning subtitles. It is safe to flush even those decoders that are not
3645 * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
3647 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3648 * before packets may be fed to the decoder.
3650 * @param avctx the codec context
3651 * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
3652 * must be freed with avsubtitle_free if *got_sub_ptr is set.
3653 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
3654 * @param[in] avpkt The input AVPacket containing the input buffer.
3656 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
3661 * Supply raw packet data as input to a decoder.
3663 * Internally, this call will copy relevant AVCodecContext fields, which can
3664 * influence decoding per-packet, and apply them when the packet is actually
3665 * decoded. (For example AVCodecContext.skip_frame, which might direct the
3666 * decoder to drop the frame contained by the packet sent with this function.)
3668 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
3669 * larger than the actual read bytes because some optimized bitstream
3670 * readers read 32 or 64 bits at once and could read over the end.
3672 * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
3673 * on the same AVCodecContext. It will return unexpected results now
3674 * or in future libavcodec versions.
3676 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3677 * before packets may be fed to the decoder.
3679 * @param avctx codec context
3680 * @param[in] avpkt The input AVPacket. Usually, this will be a single video
3681 * frame, or several complete audio frames.
3682 * Ownership of the packet remains with the caller, and the
3683 * decoder will not write to the packet. The decoder may create
3684 * a reference to the packet data (or copy it if the packet is
3685 * not reference-counted).
3686 * Unlike with older APIs, the packet is always fully consumed,
3687 * and if it contains multiple frames (e.g. some audio codecs),
3688 * will require you to call avcodec_receive_frame() multiple
3689 * times afterwards before you can send a new packet.
3690 * It can be NULL (or an AVPacket with data set to NULL and
3691 * size set to 0); in this case, it is considered a flush
3692 * packet, which signals the end of the stream. Sending the
3693 * first flush packet will return success. Subsequent ones are
3694 * unnecessary and will return AVERROR_EOF. If the decoder
3695 * still has frames buffered, it will return them after sending
3698 * @return 0 on success, otherwise negative error code:
3699 * AVERROR(EAGAIN): input is not accepted in the current state - user
3700 * must read output with avcodec_receive_frame() (once
3701 * all output is read, the packet should be resent, and
3702 * the call will not fail with EAGAIN).
3703 * AVERROR_EOF: the decoder has been flushed, and no new packets can
3704 * be sent to it (also returned if more than 1 flush
3706 * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
3707 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
3708 * other errors: legitimate decoding errors
3710 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
3713 * Return decoded output data from a decoder.
3715 * @param avctx codec context
3716 * @param frame This will be set to a reference-counted video or audio
3717 * frame (depending on the decoder type) allocated by the
3718 * decoder. Note that the function will always call
3719 * av_frame_unref(frame) before doing anything else.
3722 * 0: success, a frame was returned
3723 * AVERROR(EAGAIN): output is not available in this state - user must try
3725 * AVERROR_EOF: the decoder has been fully flushed, and there will be
3726 * no more output frames
3727 * AVERROR(EINVAL): codec not opened, or it is an encoder
3728 * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
3729 * with respect to first decoded frame. Applicable
3730 * when flag AV_CODEC_FLAG_DROPCHANGED is set.
3731 * other negative values: legitimate decoding errors
3733 int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
3736 * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
3737 * to retrieve buffered output packets.
3739 * @param avctx codec context
3740 * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
3741 * Ownership of the frame remains with the caller, and the
3742 * encoder will not write to the frame. The encoder may create
3743 * a reference to the frame data (or copy it if the frame is
3744 * not reference-counted).
3745 * It can be NULL, in which case it is considered a flush
3746 * packet. This signals the end of the stream. If the encoder
3747 * still has packets buffered, it will return them after this
3748 * call. Once flushing mode has been entered, additional flush
3749 * packets are ignored, and sending frames will return
3753 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
3754 * can have any number of samples.
3755 * If it is not set, frame->nb_samples must be equal to
3756 * avctx->frame_size for all frames except the last.
3757 * The final frame may be smaller than avctx->frame_size.
3758 * @return 0 on success, otherwise negative error code:
3759 * AVERROR(EAGAIN): input is not accepted in the current state - user
3760 * must read output with avcodec_receive_packet() (once
3761 * all output is read, the packet should be resent, and
3762 * the call will not fail with EAGAIN).
3763 * AVERROR_EOF: the encoder has been flushed, and no new frames can
3765 * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
3766 * decoder, or requires flush
3767 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
3768 * other errors: legitimate encoding errors
3770 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
3773 * Read encoded data from the encoder.
3775 * @param avctx codec context
3776 * @param avpkt This will be set to a reference-counted packet allocated by the
3777 * encoder. Note that the function will always call
3778 * av_packet_unref(avpkt) before doing anything else.
3779 * @return 0 on success, otherwise negative error code:
3780 * AVERROR(EAGAIN): output is not available in the current state - user
3781 * must try to send input
3782 * AVERROR_EOF: the encoder has been fully flushed, and there will be
3783 * no more output packets
3784 * AVERROR(EINVAL): codec not opened, or it is a decoder
3785 * other errors: legitimate encoding errors
3787 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
3790 * Create and return a AVHWFramesContext with values adequate for hardware
3791 * decoding. This is meant to get called from the get_format callback, and is
3792 * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
3793 * This API is for decoding with certain hardware acceleration modes/APIs only.
3795 * The returned AVHWFramesContext is not initialized. The caller must do this
3796 * with av_hwframe_ctx_init().
3798 * Calling this function is not a requirement, but makes it simpler to avoid
3799 * codec or hardware API specific details when manually allocating frames.
3801 * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
3802 * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
3803 * it unnecessary to call this function or having to care about
3804 * AVHWFramesContext initialization at all.
3806 * There are a number of requirements for calling this function:
3808 * - It must be called from get_format with the same avctx parameter that was
3809 * passed to get_format. Calling it outside of get_format is not allowed, and
3810 * can trigger undefined behavior.
3811 * - The function is not always supported (see description of return values).
3812 * Even if this function returns successfully, hwaccel initialization could
3813 * fail later. (The degree to which implementations check whether the stream
3814 * is actually supported varies. Some do this check only after the user's
3815 * get_format callback returns.)
3816 * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
3817 * user decides to use a AVHWFramesContext prepared with this API function,
3818 * the user must return the same hw_pix_fmt from get_format.
3819 * - The device_ref passed to this function must support the given hw_pix_fmt.
3820 * - After calling this API function, it is the user's responsibility to
3821 * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
3822 * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
3823 * before returning from get_format (this is implied by the normal
3824 * AVCodecContext.hw_frames_ctx API rules).
3825 * - The AVHWFramesContext parameters may change every time time get_format is
3826 * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
3827 * you are inherently required to go through this process again on every
3829 * - It is perfectly possible to call this function without actually using
3830 * the resulting AVHWFramesContext. One use-case might be trying to reuse a
3831 * previously initialized AVHWFramesContext, and calling this API function
3832 * only to test whether the required frame parameters have changed.
3833 * - Fields that use dynamically allocated values of any kind must not be set
3834 * by the user unless setting them is explicitly allowed by the documentation.
3835 * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
3836 * the new free callback must call the potentially set previous free callback.
3837 * This API call may set any dynamically allocated fields, including the free
3840 * The function will set at least the following fields on AVHWFramesContext
3841 * (potentially more, depending on hwaccel API):
3843 * - All fields set by av_hwframe_ctx_alloc().
3844 * - Set the format field to hw_pix_fmt.
3845 * - Set the sw_format field to the most suited and most versatile format. (An
3846 * implication is that this will prefer generic formats over opaque formats
3847 * with arbitrary restrictions, if possible.)
3848 * - Set the width/height fields to the coded frame size, rounded up to the
3849 * API-specific minimum alignment.
3850 * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
3851 * field to the number of maximum reference surfaces possible with the codec,
3852 * plus 1 surface for the user to work (meaning the user can safely reference
3853 * at most 1 decoded surface at a time), plus additional buffering introduced
3854 * by frame threading. If the hwaccel does not require pre-allocation, the
3855 * field is left to 0, and the decoder will allocate new surfaces on demand
3857 * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
3860 * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
3861 * with basic frame parameters set.
3863 * The function is stateless, and does not change the AVCodecContext or the
3864 * device_ref AVHWDeviceContext.
3866 * @param avctx The context which is currently calling get_format, and which
3867 * implicitly contains all state needed for filling the returned
3868 * AVHWFramesContext properly.
3869 * @param device_ref A reference to the AVHWDeviceContext describing the device
3870 * which will be used by the hardware decoder.
3871 * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
3872 * @param out_frames_ref On success, set to a reference to an _uninitialized_
3873 * AVHWFramesContext, created from the given device_ref.
3874 * Fields will be set to values required for decoding.
3875 * Not changed if an error is returned.
3876 * @return zero on success, a negative value on error. The following error codes
3877 * have special semantics:
3878 * AVERROR(ENOENT): the decoder does not support this functionality. Setup
3879 * is always manual, or it is a decoder which does not
3880 * support setting AVCodecContext.hw_frames_ctx at all,
3881 * or it is a software format.
3882 * AVERROR(EINVAL): it is known that hardware decoding is not supported for
3883 * this configuration, or the device_ref is not supported
3884 * for the hwaccel referenced by hw_pix_fmt.
3886 int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
3887 AVBufferRef *device_ref,
3888 enum AVPixelFormat hw_pix_fmt,
3889 AVBufferRef **out_frames_ref);
3894 * @defgroup lavc_parsing Frame parsing
3898 enum AVPictureStructure {
3899 AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
3900 AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
3901 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
3902 AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
3905 typedef struct AVCodecParserContext {
3907 struct AVCodecParser *parser;
3908 int64_t frame_offset; /* offset of the current frame */
3909 int64_t cur_offset; /* current offset
3910 (incremented by each av_parser_parse()) */
3911 int64_t next_frame_offset; /* offset of the next frame */
3913 int pict_type; /* XXX: Put it back in AVCodecContext. */
3915 * This field is used for proper frame duration computation in lavf.
3916 * It signals, how much longer the frame duration of the current frame
3917 * is compared to normal frame duration.
3919 * frame_duration = (1 + repeat_pict) * time_base
3921 * It is used by codecs like H.264 to display telecined material.
3923 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
3924 int64_t pts; /* pts of the current frame */
3925 int64_t dts; /* dts of the current frame */
3930 int fetch_timestamp;
3932 #define AV_PARSER_PTS_NB 4
3933 int cur_frame_start_index;
3934 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
3935 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
3936 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
3939 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
3940 #define PARSER_FLAG_ONCE 0x0002
3941 /// Set if the parser has a valid file offset
3942 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
3943 #define PARSER_FLAG_USE_CODEC_TS 0x1000
3945 int64_t offset; ///< byte offset from starting packet start
3946 int64_t cur_frame_end[AV_PARSER_PTS_NB];
3949 * Set by parser to 1 for key frames and 0 for non-key frames.
3950 * It is initialized to -1, so if the parser doesn't set this flag,
3951 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
3956 #if FF_API_CONVERGENCE_DURATION
3958 * @deprecated unused
3960 attribute_deprecated
3961 int64_t convergence_duration;
3964 // Timestamp generation support:
3966 * Synchronization point for start of timestamp generation.
3968 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
3971 * For example, this corresponds to presence of H.264 buffering period
3977 * Offset of the current timestamp against last timestamp sync point in
3978 * units of AVCodecContext.time_base.
3980 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3981 * contain a valid timestamp offset.
3983 * Note that the timestamp of sync point has usually a nonzero
3984 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
3985 * the next frame after timestamp sync point will be usually 1.
3987 * For example, this corresponds to H.264 cpb_removal_delay.
3989 int dts_ref_dts_delta;
3992 * Presentation delay of current frame in units of AVCodecContext.time_base.
3994 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3995 * contain valid non-negative timestamp delta (presentation time of a frame
3996 * must not lie in the past).
3998 * This delay represents the difference between decoding and presentation
3999 * time of the frame.
4001 * For example, this corresponds to H.264 dpb_output_delay.
4006 * Position of the packet in file.
4008 * Analogous to cur_frame_pts/dts
4010 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
4013 * Byte position of currently parsed frame in stream.
4018 * Previous frame byte position.
4023 * Duration of the current frame.
4024 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
4025 * For all other types, this is in units of AVCodecContext.time_base.
4029 enum AVFieldOrder field_order;
4032 * Indicate whether a picture is coded as a frame, top field or bottom field.
4034 * For example, H.264 field_pic_flag equal to 0 corresponds to
4035 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
4036 * equal to 1 and bottom_field_flag equal to 0 corresponds to
4037 * AV_PICTURE_STRUCTURE_TOP_FIELD.
4039 enum AVPictureStructure picture_structure;
4042 * Picture number incremented in presentation or output order.
4043 * This field may be reinitialized at the first picture of a new sequence.
4045 * For example, this corresponds to H.264 PicOrderCnt.
4047 int output_picture_number;
4050 * Dimensions of the decoded video intended for presentation.
4056 * Dimensions of the coded video.
4062 * The format of the coded data, corresponds to enum AVPixelFormat for video
4063 * and for enum AVSampleFormat for audio.
4065 * Note that a decoder can have considerable freedom in how exactly it
4066 * decodes the data, so the format reported here might be different from the
4067 * one returned by a decoder.
4070 } AVCodecParserContext;
4072 typedef struct AVCodecParser {
4073 int codec_ids[5]; /* several codec IDs are permitted */
4075 int (*parser_init)(AVCodecParserContext *s);
4076 /* This callback never returns an error, a negative value means that
4077 * the frame start was in a previous packet. */
4078 int (*parser_parse)(AVCodecParserContext *s,
4079 AVCodecContext *avctx,
4080 const uint8_t **poutbuf, int *poutbuf_size,
4081 const uint8_t *buf, int buf_size);
4082 void (*parser_close)(AVCodecParserContext *s);
4083 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
4084 struct AVCodecParser *next;
4088 * Iterate over all registered codec parsers.
4090 * @param opaque a pointer where libavcodec will store the iteration state. Must
4091 * point to NULL to start the iteration.
4093 * @return the next registered codec parser or NULL when the iteration is
4096 const AVCodecParser *av_parser_iterate(void **opaque);
4098 attribute_deprecated
4099 AVCodecParser *av_parser_next(const AVCodecParser *c);
4101 attribute_deprecated
4102 void av_register_codec_parser(AVCodecParser *parser);
4103 AVCodecParserContext *av_parser_init(int codec_id);
4108 * @param s parser context.
4109 * @param avctx codec context.
4110 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
4111 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
4112 * @param buf input buffer.
4113 * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
4114 size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
4115 To signal EOF, this should be 0 (so that the last frame
4117 * @param pts input presentation timestamp.
4118 * @param dts input decoding timestamp.
4119 * @param pos input byte position in stream.
4120 * @return the number of bytes of the input bitstream used.
4125 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
4132 * decode_frame(data, size);
4136 int av_parser_parse2(AVCodecParserContext *s,
4137 AVCodecContext *avctx,
4138 uint8_t **poutbuf, int *poutbuf_size,
4139 const uint8_t *buf, int buf_size,
4140 int64_t pts, int64_t dts,
4144 * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
4145 * @deprecated use AVBitStreamFilter
4147 int av_parser_change(AVCodecParserContext *s,
4148 AVCodecContext *avctx,
4149 uint8_t **poutbuf, int *poutbuf_size,
4150 const uint8_t *buf, int buf_size, int keyframe);
4151 void av_parser_close(AVCodecParserContext *s);
4159 * @addtogroup lavc_encoding
4164 * Find a registered encoder with a matching codec ID.
4166 * @param id AVCodecID of the requested encoder
4167 * @return An encoder if one was found, NULL otherwise.
4169 AVCodec *avcodec_find_encoder(enum AVCodecID id);
4172 * Find a registered encoder with the specified name.
4174 * @param name name of the requested encoder
4175 * @return An encoder if one was found, NULL otherwise.
4177 AVCodec *avcodec_find_encoder_by_name(const char *name);
4180 * Encode a frame of audio.
4182 * Takes input samples from frame and writes the next output packet, if
4183 * available, to avpkt. The output packet does not necessarily contain data for
4184 * the most recent frame, as encoders can delay, split, and combine input frames
4185 * internally as needed.
4187 * @param avctx codec context
4188 * @param avpkt output AVPacket.
4189 * The user can supply an output buffer by setting
4190 * avpkt->data and avpkt->size prior to calling the
4191 * function, but if the size of the user-provided data is not
4192 * large enough, encoding will fail. If avpkt->data and
4193 * avpkt->size are set, avpkt->destruct must also be set. All
4194 * other AVPacket fields will be reset by the encoder using
4195 * av_init_packet(). If avpkt->data is NULL, the encoder will
4196 * allocate it. The encoder will set avpkt->size to the size
4197 * of the output packet.
4199 * If this function fails or produces no output, avpkt will be
4200 * freed using av_packet_unref().
4201 * @param[in] frame AVFrame containing the raw audio data to be encoded.
4202 * May be NULL when flushing an encoder that has the
4203 * AV_CODEC_CAP_DELAY capability set.
4204 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4205 * can have any number of samples.
4206 * If it is not set, frame->nb_samples must be equal to
4207 * avctx->frame_size for all frames except the last.
4208 * The final frame may be smaller than avctx->frame_size.
4209 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4210 * output packet is non-empty, and to 0 if it is
4211 * empty. If the function returns an error, the
4212 * packet can be assumed to be invalid, and the
4213 * value of got_packet_ptr is undefined and should
4215 * @return 0 on success, negative error code on failure
4217 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
4219 attribute_deprecated
4220 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
4221 const AVFrame *frame, int *got_packet_ptr);
4224 * Encode a frame of video.
4226 * Takes input raw video data from frame and writes the next output packet, if
4227 * available, to avpkt. The output packet does not necessarily contain data for
4228 * the most recent frame, as encoders can delay and reorder input frames
4229 * internally as needed.
4231 * @param avctx codec context
4232 * @param avpkt output AVPacket.
4233 * The user can supply an output buffer by setting
4234 * avpkt->data and avpkt->size prior to calling the
4235 * function, but if the size of the user-provided data is not
4236 * large enough, encoding will fail. All other AVPacket fields
4237 * will be reset by the encoder using av_init_packet(). If
4238 * avpkt->data is NULL, the encoder will allocate it.
4239 * The encoder will set avpkt->size to the size of the
4240 * output packet. The returned data (if any) belongs to the
4241 * caller, he is responsible for freeing it.
4243 * If this function fails or produces no output, avpkt will be
4244 * freed using av_packet_unref().
4245 * @param[in] frame AVFrame containing the raw video data to be encoded.
4246 * May be NULL when flushing an encoder that has the
4247 * AV_CODEC_CAP_DELAY capability set.
4248 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4249 * output packet is non-empty, and to 0 if it is
4250 * empty. If the function returns an error, the
4251 * packet can be assumed to be invalid, and the
4252 * value of got_packet_ptr is undefined and should
4254 * @return 0 on success, negative error code on failure
4256 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
4258 attribute_deprecated
4259 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
4260 const AVFrame *frame, int *got_packet_ptr);
4262 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4263 const AVSubtitle *sub);
4270 #if FF_API_AVPICTURE
4272 * @addtogroup lavc_picture
4277 * @deprecated unused
4279 attribute_deprecated
4280 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
4283 * @deprecated unused
4285 attribute_deprecated
4286 void avpicture_free(AVPicture *picture);
4289 * @deprecated use av_image_fill_arrays() instead.
4291 attribute_deprecated
4292 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
4293 enum AVPixelFormat pix_fmt, int width, int height);
4296 * @deprecated use av_image_copy_to_buffer() instead.
4298 attribute_deprecated
4299 int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
4300 int width, int height,
4301 unsigned char *dest, int dest_size);
4304 * @deprecated use av_image_get_buffer_size() instead.
4306 attribute_deprecated
4307 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
4310 * @deprecated av_image_copy() instead.
4312 attribute_deprecated
4313 void av_picture_copy(AVPicture *dst, const AVPicture *src,
4314 enum AVPixelFormat pix_fmt, int width, int height);
4317 * @deprecated unused
4319 attribute_deprecated
4320 int av_picture_crop(AVPicture *dst, const AVPicture *src,
4321 enum AVPixelFormat pix_fmt, int top_band, int left_band);
4324 * @deprecated unused
4326 attribute_deprecated
4327 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
4328 int padtop, int padbottom, int padleft, int padright, int *color);
4336 * @defgroup lavc_misc Utility functions
4339 * Miscellaneous utility functions related to both encoding and decoding
4345 * @defgroup lavc_misc_pixfmt Pixel formats
4347 * Functions for working with pixel formats.
4351 #if FF_API_GETCHROMA
4353 * @deprecated Use av_pix_fmt_get_chroma_sub_sample
4356 attribute_deprecated
4357 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
4361 * Return a value representing the fourCC code associated to the
4362 * pixel format pix_fmt, or 0 if no associated fourCC code can be
4365 unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
4368 * @deprecated see av_get_pix_fmt_loss()
4370 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
4374 * Find the best pixel format to convert to given a certain source pixel
4375 * format. When converting from one pixel format to another, information loss
4376 * may occur. For example, when converting from RGB24 to GRAY, the color
4377 * information will be lost. Similarly, other losses occur when converting from
4378 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
4379 * the given pixel formats should be used to suffer the least amount of loss.
4380 * The pixel formats from which it chooses one, are determined by the
4381 * pix_fmt_list parameter.
4384 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
4385 * @param[in] src_pix_fmt source pixel format
4386 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4387 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
4388 * @return The best pixel format to convert to or -1 if none was found.
4390 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
4391 enum AVPixelFormat src_pix_fmt,
4392 int has_alpha, int *loss_ptr);
4395 * @deprecated see av_find_best_pix_fmt_of_2()
4397 enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4398 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4400 attribute_deprecated
4401 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4402 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4404 enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
4410 #if FF_API_TAG_STRING
4412 * Put a string representing the codec tag codec_tag in buf.
4414 * @param buf buffer to place codec tag in
4415 * @param buf_size size in bytes of buf
4416 * @param codec_tag codec tag to assign
4417 * @return the length of the string that would have been generated if
4418 * enough space had been available, excluding the trailing null
4420 * @deprecated see av_fourcc_make_string() and av_fourcc2str().
4422 attribute_deprecated
4423 size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
4426 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
4429 * Return a name for the specified profile, if available.
4431 * @param codec the codec that is searched for the given profile
4432 * @param profile the profile value for which a name is requested
4433 * @return A name for the profile if found, NULL otherwise.
4435 const char *av_get_profile_name(const AVCodec *codec, int profile);
4438 * Return a name for the specified profile, if available.
4440 * @param codec_id the ID of the codec to which the requested profile belongs
4441 * @param profile the profile value for which a name is requested
4442 * @return A name for the profile if found, NULL otherwise.
4444 * @note unlike av_get_profile_name(), which searches a list of profiles
4445 * supported by a specific decoder or encoder implementation, this
4446 * function searches the list of profiles from the AVCodecDescriptor
4448 const char *avcodec_profile_name(enum AVCodecID codec_id, int profile);
4450 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
4451 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
4452 //FIXME func typedef
4455 * Fill AVFrame audio data and linesize pointers.
4457 * The buffer buf must be a preallocated buffer with a size big enough
4458 * to contain the specified samples amount. The filled AVFrame data
4459 * pointers will point to this buffer.
4461 * AVFrame extended_data channel pointers are allocated if necessary for
4464 * @param frame the AVFrame
4465 * frame->nb_samples must be set prior to calling the
4466 * function. This function fills in frame->data,
4467 * frame->extended_data, frame->linesize[0].
4468 * @param nb_channels channel count
4469 * @param sample_fmt sample format
4470 * @param buf buffer to use for frame data
4471 * @param buf_size size of buffer
4472 * @param align plane size sample alignment (0 = default)
4473 * @return >=0 on success, negative error code on failure
4474 * @todo return the size in bytes required to store the samples in
4475 * case of success, at the next libavutil bump
4477 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
4478 enum AVSampleFormat sample_fmt, const uint8_t *buf,
4479 int buf_size, int align);
4482 * Reset the internal decoder state / flush internal buffers. Should be called
4483 * e.g. when seeking or when switching to a different stream.
4485 * @note when refcounted frames are not used (i.e. avctx->refcounted_frames is 0),
4486 * this invalidates the frames previously returned from the decoder. When
4487 * refcounted frames are used, the decoder just releases any references it might
4488 * keep internally, but the caller's reference remains valid.
4490 void avcodec_flush_buffers(AVCodecContext *avctx);
4493 * Return codec bits per sample.
4495 * @param[in] codec_id the codec
4496 * @return Number of bits per sample or zero if unknown for the given codec.
4498 int av_get_bits_per_sample(enum AVCodecID codec_id);
4501 * Return the PCM codec associated with a sample format.
4502 * @param be endianness, 0 for little, 1 for big,
4503 * -1 (or anything else) for native
4504 * @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
4506 enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
4509 * Return codec bits per sample.
4510 * Only return non-zero if the bits per sample is exactly correct, not an
4513 * @param[in] codec_id the codec
4514 * @return Number of bits per sample or zero if unknown for the given codec.
4516 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
4519 * Return audio frame duration.
4521 * @param avctx codec context
4522 * @param frame_bytes size of the frame, or 0 if unknown
4523 * @return frame duration, in samples, if known. 0 if not able to
4526 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
4529 * This function is the same as av_get_audio_frame_duration(), except it works
4530 * with AVCodecParameters instead of an AVCodecContext.
4532 int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
4535 typedef struct AVBitStreamFilterContext {
4537 const struct AVBitStreamFilter *filter;
4538 AVCodecParserContext *parser;
4539 struct AVBitStreamFilterContext *next;
4541 * Internal default arguments, used if NULL is passed to av_bitstream_filter_filter().
4542 * Not for access by library users.
4545 } AVBitStreamFilterContext;
4548 typedef struct AVBSFInternal AVBSFInternal;
4551 * The bitstream filter state.
4553 * This struct must be allocated with av_bsf_alloc() and freed with
4556 * The fields in the struct will only be changed (by the caller or by the
4557 * filter) as described in their documentation, and are to be considered
4558 * immutable otherwise.
4560 typedef struct AVBSFContext {
4562 * A class for logging and AVOptions
4564 const AVClass *av_class;
4567 * The bitstream filter this context is an instance of.
4569 const struct AVBitStreamFilter *filter;
4572 * Opaque libavcodec internal data. Must not be touched by the caller in any
4575 AVBSFInternal *internal;
4578 * Opaque filter-specific private data. If filter->priv_class is non-NULL,
4579 * this is an AVOptions-enabled struct.
4584 * Parameters of the input stream. This field is allocated in
4585 * av_bsf_alloc(), it needs to be filled by the caller before
4588 AVCodecParameters *par_in;
4591 * Parameters of the output stream. This field is allocated in
4592 * av_bsf_alloc(), it is set by the filter in av_bsf_init().
4594 AVCodecParameters *par_out;
4597 * The timebase used for the timestamps of the input packets. Set by the
4598 * caller before av_bsf_init().
4600 AVRational time_base_in;
4603 * The timebase used for the timestamps of the output packets. Set by the
4604 * filter in av_bsf_init().
4606 AVRational time_base_out;
4609 typedef struct AVBitStreamFilter {
4613 * A list of codec ids supported by the filter, terminated by
4615 * May be NULL, in that case the bitstream filter works with any codec id.
4617 const enum AVCodecID *codec_ids;
4620 * A class for the private data, used to declare bitstream filter private
4621 * AVOptions. This field is NULL for bitstream filters that do not declare
4624 * If this field is non-NULL, the first member of the filter private data
4625 * must be a pointer to AVClass, which will be set by libavcodec generic
4626 * code to this class.
4628 const AVClass *priv_class;
4630 /*****************************************************************
4631 * No fields below this line are part of the public API. They
4632 * may not be used outside of libavcodec and can be changed and
4634 * New public fields should be added right above.
4635 *****************************************************************
4639 int (*init)(AVBSFContext *ctx);
4640 int (*filter)(AVBSFContext *ctx, AVPacket *pkt);
4641 void (*close)(AVBSFContext *ctx);
4642 void (*flush)(AVBSFContext *ctx);
4643 } AVBitStreamFilter;
4647 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4648 * is deprecated. Use the new bitstream filtering API (using AVBSFContext).
4650 attribute_deprecated
4651 void av_register_bitstream_filter(AVBitStreamFilter *bsf);
4653 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4654 * is deprecated. Use av_bsf_get_by_name(), av_bsf_alloc(), and av_bsf_init()
4655 * from the new bitstream filtering API (using AVBSFContext).
4657 attribute_deprecated
4658 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
4660 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4661 * is deprecated. Use av_bsf_send_packet() and av_bsf_receive_packet() from the
4662 * new bitstream filtering API (using AVBSFContext).
4664 attribute_deprecated
4665 int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
4666 AVCodecContext *avctx, const char *args,
4667 uint8_t **poutbuf, int *poutbuf_size,
4668 const uint8_t *buf, int buf_size, int keyframe);
4670 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4671 * is deprecated. Use av_bsf_free() from the new bitstream filtering API (using
4674 attribute_deprecated
4675 void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
4677 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4678 * is deprecated. Use av_bsf_iterate() from the new bitstream filtering API (using
4681 attribute_deprecated
4682 const AVBitStreamFilter *av_bitstream_filter_next(const AVBitStreamFilter *f);
4686 * @return a bitstream filter with the specified name or NULL if no such
4687 * bitstream filter exists.
4689 const AVBitStreamFilter *av_bsf_get_by_name(const char *name);
4692 * Iterate over all registered bitstream filters.
4694 * @param opaque a pointer where libavcodec will store the iteration state. Must
4695 * point to NULL to start the iteration.
4697 * @return the next registered bitstream filter or NULL when the iteration is
4700 const AVBitStreamFilter *av_bsf_iterate(void **opaque);
4702 attribute_deprecated
4703 const AVBitStreamFilter *av_bsf_next(void **opaque);
4707 * Allocate a context for a given bitstream filter. The caller must fill in the
4708 * context parameters as described in the documentation and then call
4709 * av_bsf_init() before sending any data to the filter.
4711 * @param filter the filter for which to allocate an instance.
4712 * @param ctx a pointer into which the pointer to the newly-allocated context
4713 * will be written. It must be freed with av_bsf_free() after the
4714 * filtering is done.
4716 * @return 0 on success, a negative AVERROR code on failure
4718 int av_bsf_alloc(const AVBitStreamFilter *filter, AVBSFContext **ctx);
4721 * Prepare the filter for use, after all the parameters and options have been
4724 int av_bsf_init(AVBSFContext *ctx);
4727 * Submit a packet for filtering.
4729 * After sending each packet, the filter must be completely drained by calling
4730 * av_bsf_receive_packet() repeatedly until it returns AVERROR(EAGAIN) or
4733 * @param pkt the packet to filter. The bitstream filter will take ownership of
4734 * the packet and reset the contents of pkt. pkt is not touched if an error occurs.
4735 * If pkt is empty (i.e. NULL, or pkt->data is NULL and pkt->side_data_elems zero),
4736 * it signals the end of the stream (i.e. no more non-empty packets will be sent;
4737 * sending more empty packets does nothing) and will cause the filter to output
4738 * any packets it may have buffered internally.
4740 * @return 0 on success, a negative AVERROR on error. This function never fails if
4743 int av_bsf_send_packet(AVBSFContext *ctx, AVPacket *pkt);
4746 * Retrieve a filtered packet.
4748 * @param[out] pkt this struct will be filled with the contents of the filtered
4749 * packet. It is owned by the caller and must be freed using
4750 * av_packet_unref() when it is no longer needed.
4751 * This parameter should be "clean" (i.e. freshly allocated
4752 * with av_packet_alloc() or unreffed with av_packet_unref())
4753 * when this function is called. If this function returns
4754 * successfully, the contents of pkt will be completely
4755 * overwritten by the returned data. On failure, pkt is not
4758 * @return 0 on success. AVERROR(EAGAIN) if more packets need to be sent to the
4759 * filter (using av_bsf_send_packet()) to get more output. AVERROR_EOF if there
4760 * will be no further output from the filter. Another negative AVERROR value if
4763 * @note one input packet may result in several output packets, so after sending
4764 * a packet with av_bsf_send_packet(), this function needs to be called
4765 * repeatedly until it stops returning 0. It is also possible for a filter to
4766 * output fewer packets than were sent to it, so this function may return
4767 * AVERROR(EAGAIN) immediately after a successful av_bsf_send_packet() call.
4769 int av_bsf_receive_packet(AVBSFContext *ctx, AVPacket *pkt);
4772 * Reset the internal bitstream filter state / flush internal buffers.
4774 void av_bsf_flush(AVBSFContext *ctx);
4777 * Free a bitstream filter context and everything associated with it; write NULL
4778 * into the supplied pointer.
4780 void av_bsf_free(AVBSFContext **ctx);
4783 * Get the AVClass for AVBSFContext. It can be used in combination with
4784 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4786 * @see av_opt_find().
4788 const AVClass *av_bsf_get_class(void);
4791 * Structure for chain/list of bitstream filters.
4792 * Empty list can be allocated by av_bsf_list_alloc().
4794 typedef struct AVBSFList AVBSFList;
4797 * Allocate empty list of bitstream filters.
4798 * The list must be later freed by av_bsf_list_free()
4799 * or finalized by av_bsf_list_finalize().
4801 * @return Pointer to @ref AVBSFList on success, NULL in case of failure
4803 AVBSFList *av_bsf_list_alloc(void);
4806 * Free list of bitstream filters.
4808 * @param lst Pointer to pointer returned by av_bsf_list_alloc()
4810 void av_bsf_list_free(AVBSFList **lst);
4813 * Append bitstream filter to the list of bitstream filters.
4815 * @param lst List to append to
4816 * @param bsf Filter context to be appended
4818 * @return >=0 on success, negative AVERROR in case of failure
4820 int av_bsf_list_append(AVBSFList *lst, AVBSFContext *bsf);
4823 * Construct new bitstream filter context given it's name and options
4824 * and append it to the list of bitstream filters.
4826 * @param lst List to append to
4827 * @param bsf_name Name of the bitstream filter
4828 * @param options Options for the bitstream filter, can be set to NULL
4830 * @return >=0 on success, negative AVERROR in case of failure
4832 int av_bsf_list_append2(AVBSFList *lst, const char * bsf_name, AVDictionary **options);
4834 * Finalize list of bitstream filters.
4836 * This function will transform @ref AVBSFList to single @ref AVBSFContext,
4837 * so the whole chain of bitstream filters can be treated as single filter
4838 * freshly allocated by av_bsf_alloc().
4839 * If the call is successful, @ref AVBSFList structure is freed and lst
4840 * will be set to NULL. In case of failure, caller is responsible for
4841 * freeing the structure by av_bsf_list_free()
4843 * @param lst Filter list structure to be transformed
4844 * @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
4845 * representing the chain of bitstream filters
4847 * @return >=0 on success, negative AVERROR in case of failure
4849 int av_bsf_list_finalize(AVBSFList **lst, AVBSFContext **bsf);
4852 * Parse string describing list of bitstream filters and create single
4853 * @ref AVBSFContext describing the whole chain of bitstream filters.
4854 * Resulting @ref AVBSFContext can be treated as any other @ref AVBSFContext freshly
4855 * allocated by av_bsf_alloc().
4857 * @param str String describing chain of bitstream filters in format
4858 * `bsf1[=opt1=val1:opt2=val2][,bsf2]`
4859 * @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
4860 * representing the chain of bitstream filters
4862 * @return >=0 on success, negative AVERROR in case of failure
4864 int av_bsf_list_parse_str(const char *str, AVBSFContext **bsf);
4867 * Get null/pass-through bitstream filter.
4869 * @param[out] bsf Pointer to be set to new instance of pass-through bitstream filter
4873 int av_bsf_get_null_filter(AVBSFContext **bsf);
4878 * Same behaviour av_fast_malloc but the buffer has additional
4879 * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
4881 * In addition the whole buffer will initially and after resizes
4882 * be 0-initialized so that no uninitialized data will ever appear.
4884 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
4887 * Same behaviour av_fast_padded_malloc except that buffer will always
4888 * be 0-initialized after call.
4890 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
4893 * Encode extradata length to a buffer. Used by xiph codecs.
4895 * @param s buffer to write to; must be at least (v/255+1) bytes long
4896 * @param v size of extradata in bytes
4897 * @return number of bytes written to the buffer.
4899 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
4901 #if FF_API_USER_VISIBLE_AVHWACCEL
4903 * Register the hardware accelerator hwaccel.
4905 * @deprecated This function doesn't do anything.
4907 attribute_deprecated
4908 void av_register_hwaccel(AVHWAccel *hwaccel);
4911 * If hwaccel is NULL, returns the first registered hardware accelerator,
4912 * if hwaccel is non-NULL, returns the next registered hardware accelerator
4913 * after hwaccel, or NULL if hwaccel is the last one.
4915 * @deprecated AVHWaccel structures contain no user-serviceable parts, so
4916 * this function should not be used.
4918 attribute_deprecated
4919 AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel);
4924 * Lock operation used by lockmgr
4926 * @deprecated Deprecated together with av_lockmgr_register().
4929 AV_LOCK_CREATE, ///< Create a mutex
4930 AV_LOCK_OBTAIN, ///< Lock the mutex
4931 AV_LOCK_RELEASE, ///< Unlock the mutex
4932 AV_LOCK_DESTROY, ///< Free mutex resources
4936 * Register a user provided lock manager supporting the operations
4937 * specified by AVLockOp. The "mutex" argument to the function points
4938 * to a (void *) where the lockmgr should store/get a pointer to a user
4939 * allocated mutex. It is NULL upon AV_LOCK_CREATE and equal to the
4940 * value left by the last call for all other ops. If the lock manager is
4941 * unable to perform the op then it should leave the mutex in the same
4942 * state as when it was called and return a non-zero value. However,
4943 * when called with AV_LOCK_DESTROY the mutex will always be assumed to
4944 * have been successfully destroyed. If av_lockmgr_register succeeds
4945 * it will return a non-negative value, if it fails it will return a
4946 * negative value and destroy all mutex and unregister all callbacks.
4947 * av_lockmgr_register is not thread-safe, it must be called from a
4948 * single thread before any calls which make use of locking are used.
4950 * @param cb User defined callback. av_lockmgr_register invokes calls
4951 * to this callback and the previously registered callback.
4952 * The callback will be used to create more than one mutex
4953 * each of which must be backed by its own underlying locking
4954 * mechanism (i.e. do not use a single static object to
4955 * implement your lock manager). If cb is set to NULL the
4956 * lockmgr will be unregistered.
4958 * @deprecated This function does nothing, and always returns 0. Be sure to
4959 * build with thread support to get basic thread safety.
4961 attribute_deprecated
4962 int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
4966 * Get the type of the given codec.
4968 enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
4971 * Get the name of a codec.
4972 * @return a static string identifying the codec; never NULL
4974 const char *avcodec_get_name(enum AVCodecID id);
4977 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
4978 * with no corresponding avcodec_close()), 0 otherwise.
4980 int avcodec_is_open(AVCodecContext *s);
4983 * @return a non-zero number if codec is an encoder, zero otherwise
4985 int av_codec_is_encoder(const AVCodec *codec);
4988 * @return a non-zero number if codec is a decoder, zero otherwise
4990 int av_codec_is_decoder(const AVCodec *codec);
4993 * Allocate a CPB properties structure and initialize its fields to default
4996 * @param size if non-NULL, the size of the allocated struct will be written
4997 * here. This is useful for embedding it in side data.
4999 * @return the newly allocated struct or NULL on failure
5001 AVCPBProperties *av_cpb_properties_alloc(size_t *size);
5007 #endif /* AVCODEC_AVCODEC_H */