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)
517 * This encoder can be flushed using avcodec_flush_buffers(). If this flag is
518 * not set, the encoder must be closed and reopened to ensure that no frames
521 #define AV_CODEC_CAP_ENCODER_FLUSH (1 << 21)
523 /* Exported side data.
524 These flags can be passed in AVCodecContext.export_side_data before initialization.
527 * Export motion vectors through frame side data
529 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
531 * Export encoder Producer Reference Time through packet side data
533 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
537 * This specifies the area which should be displayed.
538 * Note there may be multiple such areas for one frame.
540 typedef struct AVPanScan {
543 * - encoding: Set by user.
544 * - decoding: Set by libavcodec.
549 * width and height in 1/16 pel
550 * - encoding: Set by user.
551 * - decoding: Set by libavcodec.
557 * position of the top left corner in 1/16 pel for up to 3 fields/frames
558 * - encoding: Set by user.
559 * - decoding: Set by libavcodec.
561 int16_t position[3][2];
565 * This structure describes the bitrate properties of an encoded bitstream. It
566 * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
567 * parameters for H.264/HEVC.
569 typedef struct AVCPBProperties {
571 * Maximum bitrate of the stream, in bits per second.
572 * Zero if unknown or unspecified.
574 #if FF_API_UNSANITIZED_BITRATES
580 * Minimum bitrate of the stream, in bits per second.
581 * Zero if unknown or unspecified.
583 #if FF_API_UNSANITIZED_BITRATES
589 * Average bitrate of the stream, in bits per second.
590 * Zero if unknown or unspecified.
592 #if FF_API_UNSANITIZED_BITRATES
599 * The size of the buffer to which the ratecontrol is applied, in bits.
600 * Zero if unknown or unspecified.
605 * The delay between the time the packet this structure is associated with
606 * is received and the time when it should be decoded, in periods of a 27MHz
609 * UINT64_MAX when unknown or unspecified.
615 * This structure supplies correlation between a packet timestamp and a wall clock
616 * production time. The definition follows the Producer Reference Time ('prft')
617 * as defined in ISO/IEC 14496-12
619 typedef struct AVProducerReferenceTime {
621 * A UTC timestamp, in microseconds, since Unix epoch (e.g, av_gettime()).
625 } AVProducerReferenceTime;
628 * The decoder will keep a reference to the frame and may reuse it later.
630 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
632 struct AVCodecInternal;
636 AV_FIELD_PROGRESSIVE,
637 AV_FIELD_TT, //< Top coded_first, top displayed first
638 AV_FIELD_BB, //< Bottom coded first, bottom displayed first
639 AV_FIELD_TB, //< Top coded first, bottom displayed first
640 AV_FIELD_BT, //< Bottom coded first, top displayed first
644 * main external API structure.
645 * New fields can be added to the end with minor version bumps.
646 * Removal, reordering and changes to existing fields require a major
648 * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
650 * The name string for AVOptions options matches the associated command line
651 * parameter name and can be found in libavcodec/options_table.h
652 * The AVOption/command line parameter names differ in some cases from the C
653 * structure field names for historic reasons or brevity.
654 * sizeof(AVCodecContext) must not be used outside libav*.
656 typedef struct AVCodecContext {
658 * information on struct for av_log
659 * - set by avcodec_alloc_context3
661 const AVClass *av_class;
662 int log_level_offset;
664 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
665 const struct AVCodec *codec;
666 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
669 * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
670 * This is used to work around some encoder bugs.
671 * A demuxer should set this to what is stored in the field used to identify the codec.
672 * If there are multiple such fields in a container then the demuxer should choose the one
673 * which maximizes the information about the used codec.
674 * If the codec tag field in a container is larger than 32 bits then the demuxer should
675 * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
676 * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
678 * - encoding: Set by user, if not then the default based on codec_id will be used.
679 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
681 unsigned int codec_tag;
686 * Private context used for internal data.
688 * Unlike priv_data, this is not codec-specific. It is used in general
689 * libavcodec functions.
691 struct AVCodecInternal *internal;
694 * Private data of the user, can be used to carry app specific stuff.
695 * - encoding: Set by user.
696 * - decoding: Set by user.
701 * the average bitrate
702 * - encoding: Set by user; unused for constant quantizer encoding.
703 * - decoding: Set by user, may be overwritten by libavcodec
704 * if this info is available in the stream
709 * number of bits the bitstream is allowed to diverge from the reference.
710 * the reference can be CBR (for CBR pass1) or VBR (for pass2)
711 * - encoding: Set by user; unused for constant quantizer encoding.
714 int bit_rate_tolerance;
717 * Global quality for codecs which cannot change it per frame.
718 * This should be proportional to MPEG-1/2/4 qscale.
719 * - encoding: Set by user.
725 * - encoding: Set by user.
728 int compression_level;
729 #define FF_COMPRESSION_DEFAULT -1
733 * - encoding: Set by user.
734 * - decoding: Set by user.
740 * - encoding: Set by user.
741 * - decoding: Set by user.
746 * some codecs need / can use extradata like Huffman tables.
747 * MJPEG: Huffman tables
748 * rv10: additional flags
749 * MPEG-4: global headers (they can be in the bitstream or here)
750 * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
751 * than extradata_size to avoid problems if it is read with the bitstream reader.
752 * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
753 * Must be allocated with the av_malloc() family of functions.
754 * - encoding: Set/allocated/freed by libavcodec.
755 * - decoding: Set/allocated/freed by user.
761 * This is the fundamental unit of time (in seconds) in terms
762 * of which frame timestamps are represented. For fixed-fps content,
763 * timebase should be 1/framerate and timestamp increments should be
765 * This often, but not always is the inverse of the frame rate or field rate
766 * for video. 1/time_base is not the average frame rate if the frame rate is not
769 * Like containers, elementary streams also can store timestamps, 1/time_base
770 * is the unit in which these timestamps are specified.
771 * As example of such codec time base see ISO/IEC 14496-2:2001(E)
772 * vop_time_increment_resolution and fixed_vop_rate
773 * (fixed_vop_rate == 0 implies that it is different from the framerate)
775 * - encoding: MUST be set by user.
776 * - decoding: the use of this field for decoding is deprecated.
777 * Use framerate instead.
779 AVRational time_base;
782 * For some codecs, the time base is closer to the field rate than the frame rate.
783 * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
784 * if no telecine is used ...
786 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
793 * Encoding: Number of frames delay there will be from the encoder input to
794 * the decoder output. (we assume the decoder matches the spec)
795 * Decoding: Number of frames delay in addition to what a standard decoder
796 * as specified in the spec would produce.
799 * Number of frames the decoded output will be delayed relative to the
803 * For encoding, this field is unused (see initial_padding).
805 * For decoding, this is the number of samples the decoder needs to
806 * output before the decoder's output is valid. When seeking, you should
807 * start decoding this many samples prior to your desired seek point.
809 * - encoding: Set by libavcodec.
810 * - decoding: Set by libavcodec.
817 * picture width / height.
819 * @note Those fields may not match the values of the last
820 * AVFrame output by avcodec_decode_video2 due frame
823 * - encoding: MUST be set by user.
824 * - decoding: May be set by the user before opening the decoder if known e.g.
825 * from the container. Some decoders will require the dimensions
826 * to be set by the caller. During decoding, the decoder may
827 * overwrite those values as required while parsing the data.
832 * Bitstream width / height, may be different from width/height e.g. when
833 * the decoded frame is cropped before being output or lowres is enabled.
835 * @note Those field may not match the value of the last
836 * AVFrame output by avcodec_receive_frame() due frame
840 * - decoding: May be set by the user before opening the decoder if known
841 * e.g. from the container. During decoding, the decoder may
842 * overwrite those values as required while parsing the data.
844 int coded_width, coded_height;
847 * the number of pictures in a group of pictures, or 0 for intra_only
848 * - encoding: Set by user.
854 * Pixel format, see AV_PIX_FMT_xxx.
855 * May be set by the demuxer if known from headers.
856 * May be overridden by the decoder if it knows better.
858 * @note This field may not match the value of the last
859 * AVFrame output by avcodec_receive_frame() due frame
862 * - encoding: Set by user.
863 * - decoding: Set by user if known, overridden by libavcodec while
866 enum AVPixelFormat pix_fmt;
869 * If non NULL, 'draw_horiz_band' is called by the libavcodec
870 * decoder to draw a horizontal band. It improves cache usage. Not
871 * all codecs can do that. You must check the codec capabilities
873 * When multithreading is used, it may be called from multiple threads
874 * at the same time; threads might draw different parts of the same AVFrame,
875 * or multiple AVFrames, and there is no guarantee that slices will be drawn
877 * The function is also used by hardware acceleration APIs.
878 * It is called at least once during frame decoding to pass
879 * the data needed for hardware render.
880 * In that mode instead of pixel data, AVFrame points to
881 * a structure specific to the acceleration API. The application
882 * reads the structure and can change some fields to indicate progress
885 * - decoding: Set by user.
886 * @param height the height of the slice
887 * @param y the y position of the slice
888 * @param type 1->top field, 2->bottom field, 3->frame
889 * @param offset offset into the AVFrame.data from which the slice should be read
891 void (*draw_horiz_band)(struct AVCodecContext *s,
892 const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
893 int y, int type, int height);
896 * callback to negotiate the pixelFormat
897 * @param fmt is the list of formats which are supported by the codec,
898 * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
899 * The first is always the native one.
900 * @note The callback may be called again immediately if initialization for
901 * the selected (hardware-accelerated) pixel format failed.
902 * @warning Behavior is undefined if the callback returns a value not
903 * in the fmt list of formats.
904 * @return the chosen format
906 * - decoding: Set by user, if not set the native format will be chosen.
908 enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
911 * maximum number of B-frames between non-B-frames
912 * Note: The output will be delayed by max_b_frames+1 relative to the input.
913 * - encoding: Set by user.
919 * qscale factor between IP and B-frames
920 * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
921 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
922 * - encoding: Set by user.
925 float b_quant_factor;
927 #if FF_API_PRIVATE_OPT
928 /** @deprecated use encoder private options instead */
930 int b_frame_strategy;
934 * qscale offset between IP and B-frames
935 * - encoding: Set by user.
938 float b_quant_offset;
941 * Size of the frame reordering buffer in the decoder.
942 * For MPEG-2 it is 1 IPB or 0 low delay IP.
943 * - encoding: Set by libavcodec.
944 * - decoding: Set by libavcodec.
948 #if FF_API_PRIVATE_OPT
949 /** @deprecated use encoder private options instead */
955 * qscale factor between P- and I-frames
956 * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
957 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
958 * - encoding: Set by user.
961 float i_quant_factor;
964 * qscale offset between P and I-frames
965 * - encoding: Set by user.
968 float i_quant_offset;
971 * luminance masking (0-> disabled)
972 * - encoding: Set by user.
978 * temporary complexity masking (0-> disabled)
979 * - encoding: Set by user.
982 float temporal_cplx_masking;
985 * spatial complexity masking (0-> disabled)
986 * - encoding: Set by user.
989 float spatial_cplx_masking;
992 * p block masking (0-> disabled)
993 * - encoding: Set by user.
999 * darkness masking (0-> disabled)
1000 * - encoding: Set by user.
1001 * - decoding: unused
1007 * - encoding: Set by libavcodec.
1008 * - decoding: Set by user (or 0).
1012 #if FF_API_PRIVATE_OPT
1013 /** @deprecated use encoder private options instead */
1014 attribute_deprecated
1015 int prediction_method;
1016 #define FF_PRED_LEFT 0
1017 #define FF_PRED_PLANE 1
1018 #define FF_PRED_MEDIAN 2
1022 * slice offsets in the frame in bytes
1023 * - encoding: Set/allocated by libavcodec.
1024 * - decoding: Set/allocated by user (or NULL).
1029 * sample aspect ratio (0 if unknown)
1030 * That is the width of a pixel divided by the height of the pixel.
1031 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1032 * - encoding: Set by user.
1033 * - decoding: Set by libavcodec.
1035 AVRational sample_aspect_ratio;
1038 * motion estimation comparison function
1039 * - encoding: Set by user.
1040 * - decoding: unused
1044 * subpixel motion estimation comparison function
1045 * - encoding: Set by user.
1046 * - decoding: unused
1050 * macroblock comparison function (not supported yet)
1051 * - encoding: Set by user.
1052 * - decoding: unused
1056 * interlaced DCT comparison function
1057 * - encoding: Set by user.
1058 * - decoding: unused
1061 #define FF_CMP_SAD 0
1062 #define FF_CMP_SSE 1
1063 #define FF_CMP_SATD 2
1064 #define FF_CMP_DCT 3
1065 #define FF_CMP_PSNR 4
1066 #define FF_CMP_BIT 5
1068 #define FF_CMP_ZERO 7
1069 #define FF_CMP_VSAD 8
1070 #define FF_CMP_VSSE 9
1071 #define FF_CMP_NSSE 10
1072 #define FF_CMP_W53 11
1073 #define FF_CMP_W97 12
1074 #define FF_CMP_DCTMAX 13
1075 #define FF_CMP_DCT264 14
1076 #define FF_CMP_MEDIAN_SAD 15
1077 #define FF_CMP_CHROMA 256
1080 * ME diamond size & shape
1081 * - encoding: Set by user.
1082 * - decoding: unused
1087 * amount of previous MV predictors (2a+1 x 2a+1 square)
1088 * - encoding: Set by user.
1089 * - decoding: unused
1091 int last_predictor_count;
1093 #if FF_API_PRIVATE_OPT
1094 /** @deprecated use encoder private options instead */
1095 attribute_deprecated
1100 * motion estimation prepass comparison function
1101 * - encoding: Set by user.
1102 * - decoding: unused
1107 * ME prepass diamond size & shape
1108 * - encoding: Set by user.
1109 * - decoding: unused
1115 * - encoding: Set by user.
1116 * - decoding: unused
1118 int me_subpel_quality;
1121 * maximum motion estimation search range in subpel units
1122 * If 0 then no limit.
1124 * - encoding: Set by user.
1125 * - decoding: unused
1131 * - encoding: unused
1132 * - decoding: Set by user.
1135 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1136 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
1137 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1140 * macroblock decision mode
1141 * - encoding: Set by user.
1142 * - decoding: unused
1145 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1146 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1147 #define FF_MB_DECISION_RD 2 ///< rate distortion
1150 * custom intra quantization matrix
1151 * Must be allocated with the av_malloc() family of functions, and will be freed in
1152 * avcodec_free_context().
1153 * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
1154 * - decoding: Set/allocated/freed by libavcodec.
1156 uint16_t *intra_matrix;
1159 * custom inter quantization matrix
1160 * Must be allocated with the av_malloc() family of functions, and will be freed in
1161 * avcodec_free_context().
1162 * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
1163 * - decoding: Set/allocated/freed by libavcodec.
1165 uint16_t *inter_matrix;
1167 #if FF_API_PRIVATE_OPT
1168 /** @deprecated use encoder private options instead */
1169 attribute_deprecated
1170 int scenechange_threshold;
1172 /** @deprecated use encoder private options instead */
1173 attribute_deprecated
1174 int noise_reduction;
1178 * precision of the intra DC coefficient - 8
1179 * - encoding: Set by user.
1180 * - decoding: Set by libavcodec
1182 int intra_dc_precision;
1185 * Number of macroblock rows at the top which are skipped.
1186 * - encoding: unused
1187 * - decoding: Set by user.
1192 * Number of macroblock rows at the bottom which are skipped.
1193 * - encoding: unused
1194 * - decoding: Set by user.
1199 * minimum MB Lagrange multiplier
1200 * - encoding: Set by user.
1201 * - decoding: unused
1206 * maximum MB Lagrange multiplier
1207 * - encoding: Set by user.
1208 * - decoding: unused
1212 #if FF_API_PRIVATE_OPT
1214 * @deprecated use encoder private options instead
1216 attribute_deprecated
1217 int me_penalty_compensation;
1221 * - encoding: Set by user.
1222 * - decoding: unused
1226 #if FF_API_PRIVATE_OPT
1227 /** @deprecated use encoder private options instead */
1228 attribute_deprecated
1234 * - encoding: Set by user.
1235 * - decoding: unused
1240 * number of reference frames
1241 * - encoding: Set by user.
1242 * - decoding: Set by lavc.
1246 #if FF_API_PRIVATE_OPT
1247 /** @deprecated use encoder private options instead */
1248 attribute_deprecated
1253 * Note: Value depends upon the compare function used for fullpel ME.
1254 * - encoding: Set by user.
1255 * - decoding: unused
1259 #if FF_API_PRIVATE_OPT
1260 /** @deprecated use encoder private options instead */
1261 attribute_deprecated
1266 * Chromaticity coordinates of the source primaries.
1267 * - encoding: Set by user
1268 * - decoding: Set by libavcodec
1270 enum AVColorPrimaries color_primaries;
1273 * Color Transfer Characteristic.
1274 * - encoding: Set by user
1275 * - decoding: Set by libavcodec
1277 enum AVColorTransferCharacteristic color_trc;
1280 * YUV colorspace type.
1281 * - encoding: Set by user
1282 * - decoding: Set by libavcodec
1284 enum AVColorSpace colorspace;
1287 * MPEG vs JPEG YUV range.
1288 * - encoding: Set by user
1289 * - decoding: Set by libavcodec
1291 enum AVColorRange color_range;
1294 * This defines the location of chroma samples.
1295 * - encoding: Set by user
1296 * - decoding: Set by libavcodec
1298 enum AVChromaLocation chroma_sample_location;
1302 * Indicates number of picture subdivisions. Used for parallelized
1304 * - encoding: Set by user
1305 * - decoding: unused
1310 * - encoding: set by libavcodec
1311 * - decoding: Set by user.
1313 enum AVFieldOrder field_order;
1316 int sample_rate; ///< samples per second
1317 int channels; ///< number of audio channels
1320 * audio sample format
1321 * - encoding: Set by user.
1322 * - decoding: Set by libavcodec.
1324 enum AVSampleFormat sample_fmt; ///< sample format
1326 /* The following data should not be initialized. */
1328 * Number of samples per channel in an audio frame.
1330 * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1331 * except the last must contain exactly frame_size samples per channel.
1332 * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1333 * frame size is not restricted.
1334 * - decoding: may be set by some decoders to indicate constant frame size
1339 * Frame counter, set by libavcodec.
1341 * - decoding: total number of frames returned from the decoder so far.
1342 * - encoding: total number of frames passed to the encoder so far.
1344 * @note the counter is not incremented if encoding/decoding resulted in
1350 * number of bytes per packet if constant and known or 0
1351 * Used by some WAV based audio codecs.
1356 * Audio cutoff bandwidth (0 means "automatic")
1357 * - encoding: Set by user.
1358 * - decoding: unused
1363 * Audio channel layout.
1364 * - encoding: set by user.
1365 * - decoding: set by user, may be overwritten by libavcodec.
1367 uint64_t channel_layout;
1370 * Request decoder to use this channel layout if it can (0 for default)
1371 * - encoding: unused
1372 * - decoding: Set by user.
1374 uint64_t request_channel_layout;
1377 * Type of service that the audio stream conveys.
1378 * - encoding: Set by user.
1379 * - decoding: Set by libavcodec.
1381 enum AVAudioServiceType audio_service_type;
1384 * desired sample format
1385 * - encoding: Not used.
1386 * - decoding: Set by user.
1387 * Decoder will decode to this format if it can.
1389 enum AVSampleFormat request_sample_fmt;
1392 * This callback is called at the beginning of each frame to get data
1393 * buffer(s) for it. There may be one contiguous buffer for all the data or
1394 * there may be a buffer per each data plane or anything in between. What
1395 * this means is, you may set however many entries in buf[] you feel necessary.
1396 * Each buffer must be reference-counted using the AVBuffer API (see description
1399 * The following fields will be set in the frame before this callback is
1402 * - width, height (video only)
1403 * - sample_rate, channel_layout, nb_samples (audio only)
1404 * Their values may differ from the corresponding values in
1405 * AVCodecContext. This callback must use the frame values, not the codec
1406 * context values, to calculate the required buffer size.
1408 * This callback must fill the following fields in the frame:
1412 * * if the data is planar audio with more than 8 channels, then this
1413 * callback must allocate and fill extended_data to contain all pointers
1414 * to all data planes. data[] must hold as many pointers as it can.
1415 * extended_data must be allocated with av_malloc() and will be freed in
1417 * * otherwise extended_data must point to data
1418 * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1419 * the frame's data and extended_data pointers must be contained in these. That
1420 * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1421 * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1422 * and av_buffer_ref().
1423 * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1424 * this callback and filled with the extra buffers if there are more
1425 * buffers than buf[] can hold. extended_buf will be freed in
1428 * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1429 * avcodec_default_get_buffer2() instead of providing buffers allocated by
1432 * Each data plane must be aligned to the maximum required by the target
1435 * @see avcodec_default_get_buffer2()
1439 * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1440 * (read and/or written to if it is writable) later by libavcodec.
1442 * avcodec_align_dimensions2() should be used to find the required width and
1443 * height, as they normally need to be rounded up to the next multiple of 16.
1445 * Some decoders do not support linesizes changing between frames.
1447 * If frame multithreading is used and thread_safe_callbacks is set,
1448 * this callback may be called from a different thread, but not from more
1449 * than one at once. Does not need to be reentrant.
1451 * @see avcodec_align_dimensions2()
1455 * Decoders request a buffer of a particular size by setting
1456 * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1457 * however, utilize only part of the buffer by setting AVFrame.nb_samples
1458 * to a smaller value in the output frame.
1460 * As a convenience, av_samples_get_buffer_size() and
1461 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1462 * functions to find the required data size and to fill data pointers and
1463 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1464 * since all planes must be the same size.
1466 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1468 * - encoding: unused
1469 * - decoding: Set by libavcodec, user can override.
1471 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
1474 * If non-zero, the decoded audio and video frames returned from
1475 * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
1476 * and are valid indefinitely. The caller must free them with
1477 * av_frame_unref() when they are not needed anymore.
1478 * Otherwise, the decoded frames must not be freed by the caller and are
1479 * only valid until the next decode call.
1481 * This is always automatically enabled if avcodec_receive_frame() is used.
1483 * - encoding: unused
1484 * - decoding: set by the caller before avcodec_open2().
1486 attribute_deprecated
1487 int refcounted_frames;
1489 /* - encoding parameters */
1490 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1491 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1495 * - encoding: Set by user.
1496 * - decoding: unused
1502 * - encoding: Set by user.
1503 * - decoding: unused
1508 * maximum quantizer difference between frames
1509 * - encoding: Set by user.
1510 * - decoding: unused
1515 * decoder bitstream buffer size
1516 * - encoding: Set by user.
1517 * - decoding: unused
1522 * ratecontrol override, see RcOverride
1523 * - encoding: Allocated/set/freed by user.
1524 * - decoding: unused
1526 int rc_override_count;
1527 RcOverride *rc_override;
1531 * - encoding: Set by user.
1532 * - decoding: Set by user, may be overwritten by libavcodec.
1534 int64_t rc_max_rate;
1538 * - encoding: Set by user.
1539 * - decoding: unused
1541 int64_t rc_min_rate;
1544 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1545 * - encoding: Set by user.
1546 * - decoding: unused.
1548 float rc_max_available_vbv_use;
1551 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1552 * - encoding: Set by user.
1553 * - decoding: unused.
1555 float rc_min_vbv_overflow_use;
1558 * Number of bits which should be loaded into the rc buffer before decoding starts.
1559 * - encoding: Set by user.
1560 * - decoding: unused
1562 int rc_initial_buffer_occupancy;
1564 #if FF_API_CODER_TYPE
1565 #define FF_CODER_TYPE_VLC 0
1566 #define FF_CODER_TYPE_AC 1
1567 #define FF_CODER_TYPE_RAW 2
1568 #define FF_CODER_TYPE_RLE 3
1570 * @deprecated use encoder private options instead
1572 attribute_deprecated
1574 #endif /* FF_API_CODER_TYPE */
1576 #if FF_API_PRIVATE_OPT
1577 /** @deprecated use encoder private options instead */
1578 attribute_deprecated
1582 #if FF_API_PRIVATE_OPT
1583 /** @deprecated use encoder private options instead */
1584 attribute_deprecated
1585 int frame_skip_threshold;
1587 /** @deprecated use encoder private options instead */
1588 attribute_deprecated
1589 int frame_skip_factor;
1591 /** @deprecated use encoder private options instead */
1592 attribute_deprecated
1595 /** @deprecated use encoder private options instead */
1596 attribute_deprecated
1598 #endif /* FF_API_PRIVATE_OPT */
1601 * trellis RD quantization
1602 * - encoding: Set by user.
1603 * - decoding: unused
1607 #if FF_API_PRIVATE_OPT
1608 /** @deprecated use encoder private options instead */
1609 attribute_deprecated
1610 int min_prediction_order;
1612 /** @deprecated use encoder private options instead */
1613 attribute_deprecated
1614 int max_prediction_order;
1616 /** @deprecated use encoder private options instead */
1617 attribute_deprecated
1618 int64_t timecode_frame_start;
1621 #if FF_API_RTP_CALLBACK
1623 * @deprecated unused
1625 /* The RTP callback: This function is called */
1626 /* every time the encoder has a packet to send. */
1627 /* It depends on the encoder if the data starts */
1628 /* with a Start Code (it should). H.263 does. */
1629 /* mb_nb contains the number of macroblocks */
1630 /* encoded in the RTP payload. */
1631 attribute_deprecated
1632 void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
1635 #if FF_API_PRIVATE_OPT
1636 /** @deprecated use encoder private options instead */
1637 attribute_deprecated
1638 int rtp_payload_size; /* The size of the RTP payload: the coder will */
1639 /* do its best to deliver a chunk with size */
1640 /* below rtp_payload_size, the chunk will start */
1641 /* with a start code on some codecs like H.263. */
1642 /* This doesn't take account of any particular */
1643 /* headers inside the transmitted RTP payload. */
1646 #if FF_API_STAT_BITS
1647 /* statistics, used for 2-pass encoding */
1648 attribute_deprecated
1650 attribute_deprecated
1652 attribute_deprecated
1654 attribute_deprecated
1656 attribute_deprecated
1658 attribute_deprecated
1660 attribute_deprecated
1662 attribute_deprecated
1665 /** @deprecated this field is unused */
1666 attribute_deprecated
1671 * pass1 encoding statistics output buffer
1672 * - encoding: Set by libavcodec.
1673 * - decoding: unused
1678 * pass2 encoding statistics input buffer
1679 * Concatenated stuff from stats_out of pass1 should be placed here.
1680 * - encoding: Allocated/set/freed by user.
1681 * - decoding: unused
1686 * Work around bugs in encoders which sometimes cannot be detected automatically.
1687 * - encoding: Set by user
1688 * - decoding: Set by user
1690 int workaround_bugs;
1691 #define FF_BUG_AUTODETECT 1 ///< autodetection
1692 #define FF_BUG_XVID_ILACE 4
1693 #define FF_BUG_UMP4 8
1694 #define FF_BUG_NO_PADDING 16
1695 #define FF_BUG_AMV 32
1696 #define FF_BUG_QPEL_CHROMA 64
1697 #define FF_BUG_STD_QPEL 128
1698 #define FF_BUG_QPEL_CHROMA2 256
1699 #define FF_BUG_DIRECT_BLOCKSIZE 512
1700 #define FF_BUG_EDGE 1024
1701 #define FF_BUG_HPEL_CHROMA 2048
1702 #define FF_BUG_DC_CLIP 4096
1703 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1704 #define FF_BUG_TRUNCATED 16384
1705 #define FF_BUG_IEDGE 32768
1708 * strictly follow the standard (MPEG-4, ...).
1709 * - encoding: Set by user.
1710 * - decoding: Set by user.
1711 * Setting this to STRICT or higher means the encoder and decoder will
1712 * generally do stupid things, whereas setting it to unofficial or lower
1713 * will mean the encoder might produce output that is not supported by all
1714 * spec-compliant decoders. Decoders don't differentiate between normal,
1715 * unofficial and experimental (that is, they always try to decode things
1716 * when they can) unless they are explicitly asked to behave stupidly
1717 * (=strictly conform to the specs)
1719 int strict_std_compliance;
1720 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
1721 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
1722 #define FF_COMPLIANCE_NORMAL 0
1723 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
1724 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
1727 * error concealment flags
1728 * - encoding: unused
1729 * - decoding: Set by user.
1731 int error_concealment;
1732 #define FF_EC_GUESS_MVS 1
1733 #define FF_EC_DEBLOCK 2
1734 #define FF_EC_FAVOR_INTER 256
1738 * - encoding: Set by user.
1739 * - decoding: Set by user.
1742 #define FF_DEBUG_PICT_INFO 1
1743 #define FF_DEBUG_RC 2
1744 #define FF_DEBUG_BITSTREAM 4
1745 #define FF_DEBUG_MB_TYPE 8
1746 #define FF_DEBUG_QP 16
1749 * @deprecated this option does nothing
1751 #define FF_DEBUG_MV 32
1753 #define FF_DEBUG_DCT_COEFF 0x00000040
1754 #define FF_DEBUG_SKIP 0x00000080
1755 #define FF_DEBUG_STARTCODE 0x00000100
1756 #define FF_DEBUG_ER 0x00000400
1757 #define FF_DEBUG_MMCO 0x00000800
1758 #define FF_DEBUG_BUGS 0x00001000
1760 #define FF_DEBUG_VIS_QP 0x00002000
1761 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
1763 #define FF_DEBUG_BUFFERS 0x00008000
1764 #define FF_DEBUG_THREADS 0x00010000
1765 #define FF_DEBUG_GREEN_MD 0x00800000
1766 #define FF_DEBUG_NOMC 0x01000000
1771 * - encoding: Set by user.
1772 * - decoding: Set by user.
1775 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
1776 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
1777 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
1781 * Error recognition; may misdetect some more or less valid parts as errors.
1782 * - encoding: unused
1783 * - decoding: Set by user.
1785 int err_recognition;
1788 * Verify checksums embedded in the bitstream (could be of either encoded or
1789 * decoded data, depending on the codec) and print an error message on mismatch.
1790 * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
1791 * decoder returning an error.
1793 #define AV_EF_CRCCHECK (1<<0)
1794 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
1795 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
1796 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
1798 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
1799 #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
1800 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
1801 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
1805 * opaque 64-bit number (generally a PTS) that will be reordered and
1806 * output in AVFrame.reordered_opaque
1807 * - encoding: Set by libavcodec to the reordered_opaque of the input
1808 * frame corresponding to the last returned packet. Only
1809 * supported by encoders with the
1810 * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
1811 * - decoding: Set by user.
1813 int64_t reordered_opaque;
1816 * Hardware accelerator in use
1817 * - encoding: unused.
1818 * - decoding: Set by libavcodec
1820 const struct AVHWAccel *hwaccel;
1823 * Hardware accelerator context.
1824 * For some hardware accelerators, a global context needs to be
1825 * provided by the user. In that case, this holds display-dependent
1826 * data FFmpeg cannot instantiate itself. Please refer to the
1827 * FFmpeg HW accelerator documentation to know how to fill this
1828 * is. e.g. for VA API, this is a struct vaapi_context.
1829 * - encoding: unused
1830 * - decoding: Set by user
1832 void *hwaccel_context;
1836 * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1837 * - decoding: unused
1839 uint64_t error[AV_NUM_DATA_POINTERS];
1842 * DCT algorithm, see FF_DCT_* below
1843 * - encoding: Set by user.
1844 * - decoding: unused
1847 #define FF_DCT_AUTO 0
1848 #define FF_DCT_FASTINT 1
1849 #define FF_DCT_INT 2
1850 #define FF_DCT_MMX 3
1851 #define FF_DCT_ALTIVEC 5
1852 #define FF_DCT_FAAN 6
1855 * IDCT algorithm, see FF_IDCT_* below.
1856 * - encoding: Set by user.
1857 * - decoding: Set by user.
1860 #define FF_IDCT_AUTO 0
1861 #define FF_IDCT_INT 1
1862 #define FF_IDCT_SIMPLE 2
1863 #define FF_IDCT_SIMPLEMMX 3
1864 #define FF_IDCT_ARM 7
1865 #define FF_IDCT_ALTIVEC 8
1866 #define FF_IDCT_SIMPLEARM 10
1867 #define FF_IDCT_XVID 14
1868 #define FF_IDCT_SIMPLEARMV5TE 16
1869 #define FF_IDCT_SIMPLEARMV6 17
1870 #define FF_IDCT_FAAN 20
1871 #define FF_IDCT_SIMPLENEON 22
1872 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
1873 #define FF_IDCT_SIMPLEAUTO 128
1876 * bits per sample/pixel from the demuxer (needed for huffyuv).
1877 * - encoding: Set by libavcodec.
1878 * - decoding: Set by user.
1880 int bits_per_coded_sample;
1883 * Bits per sample/pixel of internal libavcodec pixel/sample format.
1884 * - encoding: set by user.
1885 * - decoding: set by libavcodec.
1887 int bits_per_raw_sample;
1891 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1892 * - encoding: unused
1893 * - decoding: Set by user.
1898 #if FF_API_CODED_FRAME
1900 * the picture in the bitstream
1901 * - encoding: Set by libavcodec.
1902 * - decoding: unused
1904 * @deprecated use the quality factor packet side data instead
1906 attribute_deprecated AVFrame *coded_frame;
1911 * is used to decide how many independent tasks should be passed to execute()
1912 * - encoding: Set by user.
1913 * - decoding: Set by user.
1918 * Which multithreading methods to use.
1919 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1920 * so clients which cannot provide future frames should not use it.
1922 * - encoding: Set by user, otherwise the default is used.
1923 * - decoding: Set by user, otherwise the default is used.
1926 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1927 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1930 * Which multithreading methods are in use by the codec.
1931 * - encoding: Set by libavcodec.
1932 * - decoding: Set by libavcodec.
1934 int active_thread_type;
1937 * Set by the client if its custom get_buffer() callback can be called
1938 * synchronously from another thread, which allows faster multithreaded decoding.
1939 * draw_horiz_band() will be called from other threads regardless of this setting.
1940 * Ignored if the default get_buffer() is used.
1941 * - encoding: Set by user.
1942 * - decoding: Set by user.
1944 int thread_safe_callbacks;
1947 * The codec may call this to execute several independent things.
1948 * It will return only after finishing all tasks.
1949 * The user may replace this with some multithreaded implementation,
1950 * the default implementation will execute the parts serially.
1951 * @param count the number of things to execute
1952 * - encoding: Set by libavcodec, user can override.
1953 * - decoding: Set by libavcodec, user can override.
1955 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1958 * The codec may call this to execute several independent things.
1959 * It will return only after finishing all tasks.
1960 * The user may replace this with some multithreaded implementation,
1961 * the default implementation will execute the parts serially.
1962 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
1963 * @param c context passed also to func
1964 * @param count the number of things to execute
1965 * @param arg2 argument passed unchanged to func
1966 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1967 * @param func function that will be called count times, with jobnr from 0 to count-1.
1968 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1969 * two instances of func executing at the same time will have the same threadnr.
1970 * @return always 0 currently, but code should handle a future improvement where when any call to func
1971 * returns < 0 no further calls to func may be done and < 0 is returned.
1972 * - encoding: Set by libavcodec, user can override.
1973 * - decoding: Set by libavcodec, user can override.
1975 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1978 * noise vs. sse weight for the nsse comparison function
1979 * - encoding: Set by user.
1980 * - decoding: unused
1986 * - encoding: Set by user.
1987 * - decoding: Set by libavcodec.
1990 #define FF_PROFILE_UNKNOWN -99
1991 #define FF_PROFILE_RESERVED -100
1993 #define FF_PROFILE_AAC_MAIN 0
1994 #define FF_PROFILE_AAC_LOW 1
1995 #define FF_PROFILE_AAC_SSR 2
1996 #define FF_PROFILE_AAC_LTP 3
1997 #define FF_PROFILE_AAC_HE 4
1998 #define FF_PROFILE_AAC_HE_V2 28
1999 #define FF_PROFILE_AAC_LD 22
2000 #define FF_PROFILE_AAC_ELD 38
2001 #define FF_PROFILE_MPEG2_AAC_LOW 128
2002 #define FF_PROFILE_MPEG2_AAC_HE 131
2004 #define FF_PROFILE_DNXHD 0
2005 #define FF_PROFILE_DNXHR_LB 1
2006 #define FF_PROFILE_DNXHR_SQ 2
2007 #define FF_PROFILE_DNXHR_HQ 3
2008 #define FF_PROFILE_DNXHR_HQX 4
2009 #define FF_PROFILE_DNXHR_444 5
2011 #define FF_PROFILE_DTS 20
2012 #define FF_PROFILE_DTS_ES 30
2013 #define FF_PROFILE_DTS_96_24 40
2014 #define FF_PROFILE_DTS_HD_HRA 50
2015 #define FF_PROFILE_DTS_HD_MA 60
2016 #define FF_PROFILE_DTS_EXPRESS 70
2018 #define FF_PROFILE_MPEG2_422 0
2019 #define FF_PROFILE_MPEG2_HIGH 1
2020 #define FF_PROFILE_MPEG2_SS 2
2021 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2022 #define FF_PROFILE_MPEG2_MAIN 4
2023 #define FF_PROFILE_MPEG2_SIMPLE 5
2025 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2026 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2028 #define FF_PROFILE_H264_BASELINE 66
2029 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2030 #define FF_PROFILE_H264_MAIN 77
2031 #define FF_PROFILE_H264_EXTENDED 88
2032 #define FF_PROFILE_H264_HIGH 100
2033 #define FF_PROFILE_H264_HIGH_10 110
2034 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2035 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
2036 #define FF_PROFILE_H264_HIGH_422 122
2037 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2038 #define FF_PROFILE_H264_STEREO_HIGH 128
2039 #define FF_PROFILE_H264_HIGH_444 144
2040 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2041 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2042 #define FF_PROFILE_H264_CAVLC_444 44
2044 #define FF_PROFILE_VC1_SIMPLE 0
2045 #define FF_PROFILE_VC1_MAIN 1
2046 #define FF_PROFILE_VC1_COMPLEX 2
2047 #define FF_PROFILE_VC1_ADVANCED 3
2049 #define FF_PROFILE_MPEG4_SIMPLE 0
2050 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2051 #define FF_PROFILE_MPEG4_CORE 2
2052 #define FF_PROFILE_MPEG4_MAIN 3
2053 #define FF_PROFILE_MPEG4_N_BIT 4
2054 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2055 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2056 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2057 #define FF_PROFILE_MPEG4_HYBRID 8
2058 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2059 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2060 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2061 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2062 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2063 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2064 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2066 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
2067 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
2068 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
2069 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2070 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2072 #define FF_PROFILE_VP9_0 0
2073 #define FF_PROFILE_VP9_1 1
2074 #define FF_PROFILE_VP9_2 2
2075 #define FF_PROFILE_VP9_3 3
2077 #define FF_PROFILE_HEVC_MAIN 1
2078 #define FF_PROFILE_HEVC_MAIN_10 2
2079 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2080 #define FF_PROFILE_HEVC_REXT 4
2082 #define FF_PROFILE_AV1_MAIN 0
2083 #define FF_PROFILE_AV1_HIGH 1
2084 #define FF_PROFILE_AV1_PROFESSIONAL 2
2086 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
2087 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
2088 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
2089 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
2090 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
2092 #define FF_PROFILE_SBC_MSBC 1
2094 #define FF_PROFILE_PRORES_PROXY 0
2095 #define FF_PROFILE_PRORES_LT 1
2096 #define FF_PROFILE_PRORES_STANDARD 2
2097 #define FF_PROFILE_PRORES_HQ 3
2098 #define FF_PROFILE_PRORES_4444 4
2099 #define FF_PROFILE_PRORES_XQ 5
2101 #define FF_PROFILE_ARIB_PROFILE_A 0
2102 #define FF_PROFILE_ARIB_PROFILE_C 1
2106 * - encoding: Set by user.
2107 * - decoding: Set by libavcodec.
2110 #define FF_LEVEL_UNKNOWN -99
2113 * Skip loop filtering for selected frames.
2114 * - encoding: unused
2115 * - decoding: Set by user.
2117 enum AVDiscard skip_loop_filter;
2120 * Skip IDCT/dequantization for selected frames.
2121 * - encoding: unused
2122 * - decoding: Set by user.
2124 enum AVDiscard skip_idct;
2127 * Skip decoding for selected frames.
2128 * - encoding: unused
2129 * - decoding: Set by user.
2131 enum AVDiscard skip_frame;
2134 * Header containing style information for text subtitles.
2135 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2136 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2137 * the Format line following. It shouldn't include any Dialogue line.
2138 * - encoding: Set/allocated/freed by user (before avcodec_open2())
2139 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2141 uint8_t *subtitle_header;
2142 int subtitle_header_size;
2144 #if FF_API_VBV_DELAY
2146 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2147 * Used for compliant TS muxing.
2148 * - encoding: Set by libavcodec.
2149 * - decoding: unused.
2150 * @deprecated this value is now exported as a part of
2151 * AV_PKT_DATA_CPB_PROPERTIES packet side data
2153 attribute_deprecated
2157 #if FF_API_SIDEDATA_ONLY_PKT
2159 * Encoding only and set by default. Allow encoders to output packets
2160 * that do not contain any encoded data, only side data.
2162 * Some encoders need to output such packets, e.g. to update some stream
2163 * parameters at the end of encoding.
2165 * @deprecated this field disables the default behaviour and
2166 * it is kept only for compatibility.
2168 attribute_deprecated
2169 int side_data_only_packets;
2173 * Audio only. The number of "priming" samples (padding) inserted by the
2174 * encoder at the beginning of the audio. I.e. this number of leading
2175 * decoded samples must be discarded by the caller to get the original audio
2176 * without leading padding.
2178 * - decoding: unused
2179 * - encoding: Set by libavcodec. The timestamps on the output packets are
2180 * adjusted by the encoder so that they always refer to the
2181 * first sample of the data actually contained in the packet,
2182 * including any added padding. E.g. if the timebase is
2183 * 1/samplerate and the timestamp of the first input sample is
2184 * 0, the timestamp of the first output packet will be
2187 int initial_padding;
2190 * - decoding: For codecs that store a framerate value in the compressed
2191 * bitstream, the decoder may export it here. { 0, 1} when
2193 * - encoding: May be used to signal the framerate of CFR content to an
2196 AVRational framerate;
2199 * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
2200 * - encoding: unused.
2201 * - decoding: Set by libavcodec before calling get_format()
2203 enum AVPixelFormat sw_pix_fmt;
2206 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
2207 * - encoding unused.
2208 * - decoding set by user.
2210 AVRational pkt_timebase;
2214 * - encoding: unused.
2215 * - decoding: set by libavcodec.
2217 const AVCodecDescriptor *codec_descriptor;
2221 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2222 * - encoding: unused
2223 * - decoding: Set by user.
2229 * Current statistics for PTS correction.
2230 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
2231 * - encoding: unused
2233 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
2234 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
2235 int64_t pts_correction_last_pts; /// PTS of the last frame
2236 int64_t pts_correction_last_dts; /// DTS of the last frame
2239 * Character encoding of the input subtitles file.
2240 * - decoding: set by user
2241 * - encoding: unused
2246 * Subtitles character encoding mode. Formats or codecs might be adjusting
2247 * this setting (if they are doing the conversion themselves for instance).
2248 * - decoding: set by libavcodec
2249 * - encoding: unused
2251 int sub_charenc_mode;
2252 #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)
2253 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
2254 #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
2255 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
2258 * Skip processing alpha if supported by codec.
2259 * Note that if the format uses pre-multiplied alpha (common with VP6,
2260 * and recommended due to better video quality/compression)
2261 * the image will look as if alpha-blended onto a black background.
2262 * However for formats that do not use pre-multiplied alpha
2263 * there might be serious artefacts (though e.g. libswscale currently
2264 * assumes pre-multiplied alpha anyway).
2266 * - decoding: set by user
2267 * - encoding: unused
2272 * Number of samples to skip after a discontinuity
2273 * - decoding: unused
2274 * - encoding: set by libavcodec
2278 #if !FF_API_DEBUG_MV
2280 * debug motion vectors
2281 * - encoding: Set by user.
2282 * - decoding: Set by user.
2285 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
2286 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
2287 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2291 * custom intra quantization matrix
2292 * - encoding: Set by user, can be NULL.
2293 * - decoding: unused.
2295 uint16_t *chroma_intra_matrix;
2298 * dump format separator.
2299 * can be ", " or "\n " or anything else
2300 * - encoding: Set by user.
2301 * - decoding: Set by user.
2303 uint8_t *dump_separator;
2306 * ',' separated list of allowed decoders.
2307 * If NULL then all are allowed
2308 * - encoding: unused
2309 * - decoding: set by user
2311 char *codec_whitelist;
2314 * Properties of the stream that gets decoded
2315 * - encoding: unused
2316 * - decoding: set by libavcodec
2318 unsigned properties;
2319 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
2320 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
2323 * Additional data associated with the entire coded stream.
2325 * - decoding: unused
2326 * - encoding: may be set by libavcodec after avcodec_open2().
2328 AVPacketSideData *coded_side_data;
2329 int nb_coded_side_data;
2332 * A reference to the AVHWFramesContext describing the input (for encoding)
2333 * or output (decoding) frames. The reference is set by the caller and
2334 * afterwards owned (and freed) by libavcodec - it should never be read by
2335 * the caller after being set.
2337 * - decoding: This field should be set by the caller from the get_format()
2338 * callback. The previous reference (if any) will always be
2339 * unreffed by libavcodec before the get_format() call.
2341 * If the default get_buffer2() is used with a hwaccel pixel
2342 * format, then this AVHWFramesContext will be used for
2343 * allocating the frame buffers.
2345 * - encoding: For hardware encoders configured to use a hwaccel pixel
2346 * format, this field should be set by the caller to a reference
2347 * to the AVHWFramesContext describing input frames.
2348 * AVHWFramesContext.format must be equal to
2349 * AVCodecContext.pix_fmt.
2351 * This field should be set before avcodec_open2() is called.
2353 AVBufferRef *hw_frames_ctx;
2356 * Control the form of AVSubtitle.rects[N]->ass
2357 * - decoding: set by user
2358 * - encoding: unused
2360 int sub_text_format;
2361 #define FF_SUB_TEXT_FMT_ASS 0
2362 #if FF_API_ASS_TIMING
2363 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
2367 * Audio only. The amount of padding (in samples) appended by the encoder to
2368 * the end of the audio. I.e. this number of decoded samples must be
2369 * discarded by the caller from the end of the stream to get the original
2370 * audio without any trailing padding.
2372 * - decoding: unused
2373 * - encoding: unused
2375 int trailing_padding;
2378 * The number of pixels per image to maximally accept.
2380 * - decoding: set by user
2381 * - encoding: set by user
2386 * A reference to the AVHWDeviceContext describing the device which will
2387 * be used by a hardware encoder/decoder. The reference is set by the
2388 * caller and afterwards owned (and freed) by libavcodec.
2390 * This should be used if either the codec device does not require
2391 * hardware frames or any that are used are to be allocated internally by
2392 * libavcodec. If the user wishes to supply any of the frames used as
2393 * encoder input or decoder output then hw_frames_ctx should be used
2394 * instead. When hw_frames_ctx is set in get_format() for a decoder, this
2395 * field will be ignored while decoding the associated stream segment, but
2396 * may again be used on a following one after another get_format() call.
2398 * For both encoders and decoders this field should be set before
2399 * avcodec_open2() is called and must not be written to thereafter.
2401 * Note that some decoders may require this field to be set initially in
2402 * order to support hw_frames_ctx at all - in that case, all frames
2403 * contexts used must be created on the same device.
2405 AVBufferRef *hw_device_ctx;
2408 * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
2409 * decoding (if active).
2410 * - encoding: unused
2411 * - decoding: Set by user (either before avcodec_open2(), or in the
2412 * AVCodecContext.get_format callback)
2417 * Video decoding only. Certain video codecs support cropping, meaning that
2418 * only a sub-rectangle of the decoded frame is intended for display. This
2419 * option controls how cropping is handled by libavcodec.
2421 * When set to 1 (the default), libavcodec will apply cropping internally.
2422 * I.e. it will modify the output frame width/height fields and offset the
2423 * data pointers (only by as much as possible while preserving alignment, or
2424 * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
2425 * the frames output by the decoder refer only to the cropped area. The
2426 * crop_* fields of the output frames will be zero.
2428 * When set to 0, the width/height fields of the output frames will be set
2429 * to the coded dimensions and the crop_* fields will describe the cropping
2430 * rectangle. Applying the cropping is left to the caller.
2432 * @warning When hardware acceleration with opaque output frames is used,
2433 * libavcodec is unable to apply cropping from the top/left border.
2435 * @note when this option is set to zero, the width/height fields of the
2436 * AVCodecContext and output AVFrames have different meanings. The codec
2437 * context fields store display dimensions (with the coded dimensions in
2438 * coded_width/height), while the frame fields store the coded dimensions
2439 * (with the display dimensions being determined by the crop_* fields).
2444 * Video decoding only. Sets the number of extra hardware frames which
2445 * the decoder will allocate for use by the caller. This must be set
2446 * before avcodec_open2() is called.
2448 * Some hardware decoders require all frames that they will use for
2449 * output to be defined in advance before decoding starts. For such
2450 * decoders, the hardware frame pool must therefore be of a fixed size.
2451 * The extra frames set here are on top of any number that the decoder
2452 * needs internally in order to operate normally (for example, frames
2453 * used as reference pictures).
2455 int extra_hw_frames;
2458 * The percentage of damaged samples to discard a frame.
2460 * - decoding: set by user
2461 * - encoding: unused
2463 int discard_damaged_percentage;
2466 * The number of samples per frame to maximally accept.
2468 * - decoding: set by user
2469 * - encoding: set by user
2471 int64_t max_samples;
2474 * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
2475 * metadata exported in frame, packet, or coded stream side data by
2476 * decoders and encoders.
2478 * - decoding: set by user
2479 * - encoding: set by user
2481 int export_side_data;
2484 #if FF_API_CODEC_GET_SET
2486 * Accessors for some AVCodecContext fields. These used to be provided for ABI
2487 * compatibility, and do not need to be used anymore.
2489 attribute_deprecated
2490 AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
2491 attribute_deprecated
2492 void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
2494 attribute_deprecated
2495 const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
2496 attribute_deprecated
2497 void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
2499 attribute_deprecated
2500 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
2503 attribute_deprecated
2504 int av_codec_get_lowres(const AVCodecContext *avctx);
2505 attribute_deprecated
2506 void av_codec_set_lowres(AVCodecContext *avctx, int val);
2509 attribute_deprecated
2510 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
2511 attribute_deprecated
2512 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
2514 attribute_deprecated
2515 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
2516 attribute_deprecated
2517 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
2523 typedef struct AVProfile {
2525 const char *name; ///< short name for the profile
2530 * The codec supports this format via the hw_device_ctx interface.
2532 * When selecting this format, AVCodecContext.hw_device_ctx should
2533 * have been set to a device of the specified type before calling
2536 AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX = 0x01,
2538 * The codec supports this format via the hw_frames_ctx interface.
2540 * When selecting this format for a decoder,
2541 * AVCodecContext.hw_frames_ctx should be set to a suitable frames
2542 * context inside the get_format() callback. The frames context
2543 * must have been created on a device of the specified type.
2545 AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX = 0x02,
2547 * The codec supports this format by some internal method.
2549 * This format can be selected without any additional configuration -
2550 * no device or frames context is required.
2552 AV_CODEC_HW_CONFIG_METHOD_INTERNAL = 0x04,
2554 * The codec supports this format by some ad-hoc method.
2556 * Additional settings and/or function calls are required. See the
2557 * codec-specific documentation for details. (Methods requiring
2558 * this sort of configuration are deprecated and others should be
2559 * used in preference.)
2561 AV_CODEC_HW_CONFIG_METHOD_AD_HOC = 0x08,
2564 typedef struct AVCodecHWConfig {
2566 * A hardware pixel format which the codec can use.
2568 enum AVPixelFormat pix_fmt;
2570 * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
2571 * setup methods which can be used with this configuration.
2575 * The device type associated with the configuration.
2577 * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
2578 * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
2580 enum AVHWDeviceType device_type;
2583 typedef struct AVCodecDefault AVCodecDefault;
2590 typedef struct AVCodec {
2592 * Name of the codec implementation.
2593 * The name is globally unique among encoders and among decoders (but an
2594 * encoder and a decoder can share the same name).
2595 * This is the primary way to find a codec from the user perspective.
2599 * Descriptive name for the codec, meant to be more human readable than name.
2600 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
2602 const char *long_name;
2603 enum AVMediaType type;
2606 * Codec capabilities.
2607 * see AV_CODEC_CAP_*
2610 const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
2611 const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
2612 const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
2613 const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
2614 const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
2615 uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
2616 const AVClass *priv_class; ///< AVClass for the private context
2617 const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
2620 * Group name of the codec implementation.
2621 * This is a short symbolic name of the wrapper backing this codec. A
2622 * wrapper uses some kind of external implementation for the codec, such
2623 * as an external library, or a codec implementation provided by the OS or
2625 * If this field is NULL, this is a builtin, libavcodec native codec.
2626 * If non-NULL, this will be the suffix in AVCodec.name in most cases
2627 * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
2629 const char *wrapper_name;
2631 /*****************************************************************
2632 * No fields below this line are part of the public API. They
2633 * may not be used outside of libavcodec and can be changed and
2635 * New public fields should be added right above.
2636 *****************************************************************
2639 struct AVCodec *next;
2641 * @name Frame-level threading support functions
2645 * Copy necessary context variables from a previous thread context to the current one.
2646 * If not defined, the next thread will start automatically; otherwise, the codec
2647 * must call ff_thread_finish_setup().
2649 * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
2651 int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
2655 * Private codec-specific defaults.
2657 const AVCodecDefault *defaults;
2660 * Initialize codec static data, called from avcodec_register().
2662 * This is not intended for time consuming operations as it is
2663 * run for every codec regardless of that codec being used.
2665 void (*init_static_data)(struct AVCodec *codec);
2667 int (*init)(AVCodecContext *);
2668 int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
2669 const struct AVSubtitle *sub);
2671 * Encode data to an AVPacket.
2673 * @param avctx codec context
2674 * @param avpkt output AVPacket (may contain a user-provided buffer)
2675 * @param[in] frame AVFrame containing the raw data to be encoded
2676 * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
2677 * non-empty packet was returned in avpkt.
2678 * @return 0 on success, negative error code on failure
2680 int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
2681 int *got_packet_ptr);
2682 int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
2683 int (*close)(AVCodecContext *);
2685 * Encode API with decoupled packet/frame dataflow. The API is the
2686 * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
2688 * - never called if the codec is closed or the wrong type,
2689 * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
2690 * - only one drain frame is ever passed down,
2692 int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
2693 int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
2696 * Decode API with decoupled packet/frame dataflow. This function is called
2697 * to get one output frame. It should call ff_decode_get_packet() to obtain
2700 int (*receive_frame)(AVCodecContext *avctx, AVFrame *frame);
2703 * Will be called when seeking
2705 void (*flush)(AVCodecContext *);
2707 * Internal codec capabilities.
2708 * See FF_CODEC_CAP_* in internal.h
2713 * Decoding only, a comma-separated list of bitstream filters to apply to
2714 * packets before decoding.
2719 * Array of pointers to hardware configurations supported by the codec,
2720 * or NULL if no hardware supported. The array is terminated by a NULL
2723 * The user can only access this field via avcodec_get_hw_config().
2725 const struct AVCodecHWConfigInternal **hw_configs;
2728 * List of supported codec_tags, terminated by FF_CODEC_TAGS_END.
2730 const uint32_t *codec_tags;
2733 #if FF_API_CODEC_GET_SET
2734 attribute_deprecated
2735 int av_codec_get_max_lowres(const AVCodec *codec);
2738 struct MpegEncContext;
2741 * Retrieve supported hardware configurations for a codec.
2743 * Values of index from zero to some maximum return the indexed configuration
2744 * descriptor; all other values return NULL. If the codec does not support
2745 * any hardware configurations then it will always return NULL.
2747 const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
2750 * @defgroup lavc_hwaccel AVHWAccel
2752 * @note Nothing in this structure should be accessed by the user. At some
2753 * point in future it will not be externally visible at all.
2757 typedef struct AVHWAccel {
2759 * Name of the hardware accelerated codec.
2760 * The name is globally unique among encoders and among decoders (but an
2761 * encoder and a decoder can share the same name).
2766 * Type of codec implemented by the hardware accelerator.
2768 * See AVMEDIA_TYPE_xxx
2770 enum AVMediaType type;
2773 * Codec implemented by the hardware accelerator.
2775 * See AV_CODEC_ID_xxx
2780 * Supported pixel format.
2782 * Only hardware accelerated formats are supported here.
2784 enum AVPixelFormat pix_fmt;
2787 * Hardware accelerated codec capabilities.
2788 * see AV_HWACCEL_CODEC_CAP_*
2792 /*****************************************************************
2793 * No fields below this line are part of the public API. They
2794 * may not be used outside of libavcodec and can be changed and
2796 * New public fields should be added right above.
2797 *****************************************************************
2801 * Allocate a custom buffer
2803 int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
2806 * Called at the beginning of each frame or field picture.
2808 * Meaningful frame information (codec specific) is guaranteed to
2809 * be parsed at this point. This function is mandatory.
2811 * Note that buf can be NULL along with buf_size set to 0.
2812 * Otherwise, this means the whole frame is available at this point.
2814 * @param avctx the codec context
2815 * @param buf the frame data buffer base
2816 * @param buf_size the size of the frame in bytes
2817 * @return zero if successful, a negative value otherwise
2819 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2822 * Callback for parameter data (SPS/PPS/VPS etc).
2824 * Useful for hardware decoders which keep persistent state about the
2825 * video parameters, and need to receive any changes to update that state.
2827 * @param avctx the codec context
2828 * @param type the nal unit type
2829 * @param buf the nal unit data buffer
2830 * @param buf_size the size of the nal unit in bytes
2831 * @return zero if successful, a negative value otherwise
2833 int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
2836 * Callback for each slice.
2838 * Meaningful slice information (codec specific) is guaranteed to
2839 * be parsed at this point. This function is mandatory.
2840 * The only exception is XvMC, that works on MB level.
2842 * @param avctx the codec context
2843 * @param buf the slice data buffer base
2844 * @param buf_size the size of the slice in bytes
2845 * @return zero if successful, a negative value otherwise
2847 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2850 * Called at the end of each frame or field picture.
2852 * The whole picture is parsed at this point and can now be sent
2853 * to the hardware accelerator. This function is mandatory.
2855 * @param avctx the codec context
2856 * @return zero if successful, a negative value otherwise
2858 int (*end_frame)(AVCodecContext *avctx);
2861 * Size of per-frame hardware accelerator private data.
2863 * Private data is allocated with av_mallocz() before
2864 * AVCodecContext.get_buffer() and deallocated after
2865 * AVCodecContext.release_buffer().
2867 int frame_priv_data_size;
2870 * Called for every Macroblock in a slice.
2872 * XvMC uses it to replace the ff_mpv_reconstruct_mb().
2873 * Instead of decoding to raw picture, MB parameters are
2874 * stored in an array provided by the video driver.
2876 * @param s the mpeg context
2878 void (*decode_mb)(struct MpegEncContext *s);
2881 * Initialize the hwaccel private data.
2883 * This will be called from ff_get_format(), after hwaccel and
2884 * hwaccel_context are set and the hwaccel private data in AVCodecInternal
2887 int (*init)(AVCodecContext *avctx);
2890 * Uninitialize the hwaccel private data.
2892 * This will be called from get_format() or avcodec_close(), after hwaccel
2893 * and hwaccel_context are already uninitialized.
2895 int (*uninit)(AVCodecContext *avctx);
2898 * Size of the private data to allocate in
2899 * AVCodecInternal.hwaccel_priv_data.
2904 * Internal hwaccel capabilities.
2909 * Fill the given hw_frames context with current codec parameters. Called
2910 * from get_format. Refer to avcodec_get_hw_frames_parameters() for
2913 * This CAN be called before AVHWAccel.init is called, and you must assume
2914 * that avctx->hwaccel_priv_data is invalid.
2916 int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
2920 * HWAccel is experimental and is thus avoided in favor of non experimental
2923 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2926 * Hardware acceleration should be used for decoding even if the codec level
2927 * used is unknown or higher than the maximum supported level reported by the
2930 * It's generally a good idea to pass this flag unless you have a specific
2931 * reason not to, as hardware tends to under-report supported levels.
2933 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2936 * Hardware acceleration can output YUV pixel formats with a different chroma
2937 * sampling than 4:2:0 and/or other than 8 bits per component.
2939 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2942 * Hardware acceleration should still be attempted for decoding when the
2943 * codec profile does not match the reported capabilities of the hardware.
2945 * For example, this can be used to try to decode baseline profile H.264
2946 * streams in hardware - it will often succeed, because many streams marked
2947 * as baseline profile actually conform to constrained baseline profile.
2949 * @warning If the stream is actually not supported then the behaviour is
2950 * undefined, and may include returning entirely incorrect output
2951 * while indicating success.
2953 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2959 #if FF_API_AVPICTURE
2961 * @defgroup lavc_picture AVPicture
2963 * Functions for working with AVPicture
2968 * Picture data structure.
2970 * Up to four components can be stored into it, the last component is
2972 * @deprecated use AVFrame or imgutils functions instead
2974 typedef struct AVPicture {
2975 attribute_deprecated
2976 uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
2977 attribute_deprecated
2978 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
2986 enum AVSubtitleType {
2989 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2992 * Plain text, the text field must be set by the decoder and is
2993 * authoritative. ass and pict fields may contain approximations.
2998 * Formatted text, the ass field must be set by the decoder and is
2999 * authoritative. pict and text fields may contain approximations.
3004 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3006 typedef struct AVSubtitleRect {
3007 int x; ///< top left corner of pict, undefined when pict is not set
3008 int y; ///< top left corner of pict, undefined when pict is not set
3009 int w; ///< width of pict, undefined when pict is not set
3010 int h; ///< height of pict, undefined when pict is not set
3011 int nb_colors; ///< number of colors in pict, undefined when pict is not set
3013 #if FF_API_AVPICTURE
3015 * @deprecated unused
3017 attribute_deprecated
3021 * data+linesize for the bitmap of this subtitle.
3022 * Can be set for text/ass as well once they are rendered.
3027 enum AVSubtitleType type;
3029 char *text; ///< 0 terminated plain UTF-8 text
3032 * 0 terminated ASS/SSA compatible event line.
3033 * The presentation of this is unaffected by the other values in this
3041 typedef struct AVSubtitle {
3042 uint16_t format; /* 0 = graphics */
3043 uint32_t start_display_time; /* relative to packet pts, in ms */
3044 uint32_t end_display_time; /* relative to packet pts, in ms */
3046 AVSubtitleRect **rects;
3047 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3051 * This struct describes the properties of an encoded stream.
3053 * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3054 * be allocated with avcodec_parameters_alloc() and freed with
3055 * avcodec_parameters_free().
3057 typedef struct AVCodecParameters {
3059 * General type of the encoded data.
3061 enum AVMediaType codec_type;
3063 * Specific type of the encoded data (the codec used).
3065 enum AVCodecID codec_id;
3067 * Additional information about the codec (corresponds to the AVI FOURCC).
3072 * Extra binary data needed for initializing the decoder, codec-dependent.
3074 * Must be allocated with av_malloc() and will be freed by
3075 * avcodec_parameters_free(). The allocated size of extradata must be at
3076 * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3081 * Size of the extradata content in bytes.
3086 * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3087 * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3092 * The average bitrate of the encoded data (in bits per second).
3097 * The number of bits per sample in the codedwords.
3099 * This is basically the bitrate per sample. It is mandatory for a bunch of
3100 * formats to actually decode them. It's the number of bits for one sample in
3101 * the actual coded bitstream.
3103 * This could be for example 4 for ADPCM
3104 * For PCM formats this matches bits_per_raw_sample
3107 int bits_per_coded_sample;
3110 * This is the number of valid bits in each output sample. If the
3111 * sample format has more bits, the least significant bits are additional
3112 * padding bits, which are always 0. Use right shifts to reduce the sample
3113 * to its actual size. For example, audio formats with 24 bit samples will
3114 * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
3115 * To get the original sample use "(int32_t)sample >> 8"."
3117 * For ADPCM this might be 12 or 16 or similar
3120 int bits_per_raw_sample;
3123 * Codec-specific bitstream restrictions that the stream conforms to.
3129 * Video only. The dimensions of the video frame in pixels.
3135 * Video only. The aspect ratio (width / height) which a single pixel
3136 * should have when displayed.
3138 * When the aspect ratio is unknown / undefined, the numerator should be
3139 * set to 0 (the denominator may have any value).
3141 AVRational sample_aspect_ratio;
3144 * Video only. The order of the fields in interlaced video.
3146 enum AVFieldOrder field_order;
3149 * Video only. Additional colorspace characteristics.
3151 enum AVColorRange color_range;
3152 enum AVColorPrimaries color_primaries;
3153 enum AVColorTransferCharacteristic color_trc;
3154 enum AVColorSpace color_space;
3155 enum AVChromaLocation chroma_location;
3158 * Video only. Number of delayed frames.
3163 * Audio only. The channel layout bitmask. May be 0 if the channel layout is
3164 * unknown or unspecified, otherwise the number of bits set must be equal to
3165 * the channels field.
3167 uint64_t channel_layout;
3169 * Audio only. The number of audio channels.
3173 * Audio only. The number of audio samples per second.
3177 * Audio only. The number of bytes per coded audio frame, required by some
3180 * Corresponds to nBlockAlign in WAVEFORMATEX.
3184 * Audio only. Audio frame size, if known. Required by some formats to be static.
3189 * Audio only. The amount of padding (in samples) inserted by the encoder at
3190 * the beginning of the audio. I.e. this number of leading decoded samples
3191 * must be discarded by the caller to get the original audio without leading
3194 int initial_padding;
3196 * Audio only. The amount of padding (in samples) appended by the encoder to
3197 * the end of the audio. I.e. this number of decoded samples must be
3198 * discarded by the caller from the end of the stream to get the original
3199 * audio without any trailing padding.
3201 int trailing_padding;
3203 * Audio only. Number of samples to skip after a discontinuity.
3206 } AVCodecParameters;
3209 * Iterate over all registered codecs.
3211 * @param opaque a pointer where libavcodec will store the iteration state. Must
3212 * point to NULL to start the iteration.
3214 * @return the next registered codec or NULL when the iteration is
3217 const AVCodec *av_codec_iterate(void **opaque);
3221 * If c is NULL, returns the first registered codec,
3222 * if c is non-NULL, returns the next registered codec after c,
3223 * or NULL if c is the last one.
3225 attribute_deprecated
3226 AVCodec *av_codec_next(const AVCodec *c);
3230 * Return the LIBAVCODEC_VERSION_INT constant.
3232 unsigned avcodec_version(void);
3235 * Return the libavcodec build-time configuration.
3237 const char *avcodec_configuration(void);
3240 * Return the libavcodec license.
3242 const char *avcodec_license(void);
3246 * Register the codec codec and initialize libavcodec.
3248 * @warning either this function or avcodec_register_all() must be called
3249 * before any other libavcodec functions.
3251 * @see avcodec_register_all()
3253 attribute_deprecated
3254 void avcodec_register(AVCodec *codec);
3257 * Register all the codecs, parsers and bitstream filters which were enabled at
3258 * configuration time. If you do not call this function you can select exactly
3259 * which formats you want to support, by using the individual registration
3262 * @see avcodec_register
3263 * @see av_register_codec_parser
3264 * @see av_register_bitstream_filter
3266 attribute_deprecated
3267 void avcodec_register_all(void);
3271 * Allocate an AVCodecContext and set its fields to default values. The
3272 * resulting struct should be freed with avcodec_free_context().
3274 * @param codec if non-NULL, allocate private data and initialize defaults
3275 * for the given codec. It is illegal to then call avcodec_open2()
3276 * with a different codec.
3277 * If NULL, then the codec-specific defaults won't be initialized,
3278 * which may result in suboptimal default settings (this is
3279 * important mainly for encoders, e.g. libx264).
3281 * @return An AVCodecContext filled with default values or NULL on failure.
3283 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
3286 * Free the codec context and everything associated with it and write NULL to
3287 * the provided pointer.
3289 void avcodec_free_context(AVCodecContext **avctx);
3291 #if FF_API_GET_CONTEXT_DEFAULTS
3293 * @deprecated This function should not be used, as closing and opening a codec
3294 * context multiple time is not supported. A new codec context should be
3295 * allocated for each new use.
3297 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
3301 * Get the AVClass for AVCodecContext. It can be used in combination with
3302 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3304 * @see av_opt_find().
3306 const AVClass *avcodec_get_class(void);
3308 #if FF_API_COPY_CONTEXT
3310 * Get the AVClass for AVFrame. It can be used in combination with
3311 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3313 * @see av_opt_find().
3315 const AVClass *avcodec_get_frame_class(void);
3318 * Get the AVClass for AVSubtitleRect. It can be used in combination with
3319 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3321 * @see av_opt_find().
3323 const AVClass *avcodec_get_subtitle_rect_class(void);
3326 * Copy the settings of the source AVCodecContext into the destination
3327 * AVCodecContext. The resulting destination codec context will be
3328 * unopened, i.e. you are required to call avcodec_open2() before you
3329 * can use this AVCodecContext to decode/encode video/audio data.
3331 * @param dest target codec context, should be initialized with
3332 * avcodec_alloc_context3(NULL), but otherwise uninitialized
3333 * @param src source codec context
3334 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
3336 * @deprecated The semantics of this function are ill-defined and it should not
3337 * be used. If you need to transfer the stream parameters from one codec context
3338 * to another, use an intermediate AVCodecParameters instance and the
3339 * avcodec_parameters_from_context() / avcodec_parameters_to_context()
3342 attribute_deprecated
3343 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
3347 * Allocate a new AVCodecParameters and set its fields to default values
3348 * (unknown/invalid/0). The returned struct must be freed with
3349 * avcodec_parameters_free().
3351 AVCodecParameters *avcodec_parameters_alloc(void);
3354 * Free an AVCodecParameters instance and everything associated with it and
3355 * write NULL to the supplied pointer.
3357 void avcodec_parameters_free(AVCodecParameters **par);
3360 * Copy the contents of src to dst. Any allocated fields in dst are freed and
3361 * replaced with newly allocated duplicates of the corresponding fields in src.
3363 * @return >= 0 on success, a negative AVERROR code on failure.
3365 int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src);
3368 * Fill the parameters struct based on the values from the supplied codec
3369 * context. Any allocated fields in par are freed and replaced with duplicates
3370 * of the corresponding fields in codec.
3372 * @return >= 0 on success, a negative AVERROR code on failure
3374 int avcodec_parameters_from_context(AVCodecParameters *par,
3375 const AVCodecContext *codec);
3378 * Fill the codec context based on the values from the supplied codec
3379 * parameters. Any allocated fields in codec that have a corresponding field in
3380 * par are freed and replaced with duplicates of the corresponding field in par.
3381 * Fields in codec that do not have a counterpart in par are not touched.
3383 * @return >= 0 on success, a negative AVERROR code on failure.
3385 int avcodec_parameters_to_context(AVCodecContext *codec,
3386 const AVCodecParameters *par);
3389 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
3390 * function the context has to be allocated with avcodec_alloc_context3().
3392 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
3393 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
3394 * retrieving a codec.
3396 * @warning This function is not thread safe!
3398 * @note Always call this function before using decoding routines (such as
3399 * @ref avcodec_receive_frame()).
3402 * avcodec_register_all();
3403 * av_dict_set(&opts, "b", "2.5M", 0);
3404 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
3408 * context = avcodec_alloc_context3(codec);
3410 * if (avcodec_open2(context, codec, opts) < 0)
3414 * @param avctx The context to initialize.
3415 * @param codec The codec to open this context for. If a non-NULL codec has been
3416 * previously passed to avcodec_alloc_context3() or
3417 * for this context, then this parameter MUST be either NULL or
3418 * equal to the previously passed codec.
3419 * @param options A dictionary filled with AVCodecContext and codec-private options.
3420 * On return this object will be filled with options that were not found.
3422 * @return zero on success, a negative value on error
3423 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
3424 * av_dict_set(), av_opt_find().
3426 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
3429 * Close a given AVCodecContext and free all the data associated with it
3430 * (but not the AVCodecContext itself).
3432 * Calling this function on an AVCodecContext that hasn't been opened will free
3433 * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
3434 * codec. Subsequent calls will do nothing.
3436 * @note Do not use this function. Use avcodec_free_context() to destroy a
3437 * codec context (either open or closed). Opening and closing a codec context
3438 * multiple times is not supported anymore -- use multiple codec contexts
3441 int avcodec_close(AVCodecContext *avctx);
3444 * Free all allocated data in the given subtitle struct.
3446 * @param sub AVSubtitle to free.
3448 void avsubtitle_free(AVSubtitle *sub);
3455 * @addtogroup lavc_decoding
3460 * Find a registered decoder with a matching codec ID.
3462 * @param id AVCodecID of the requested decoder
3463 * @return A decoder if one was found, NULL otherwise.
3465 AVCodec *avcodec_find_decoder(enum AVCodecID id);
3468 * Find a registered decoder with the specified name.
3470 * @param name name of the requested decoder
3471 * @return A decoder if one was found, NULL otherwise.
3473 AVCodec *avcodec_find_decoder_by_name(const char *name);
3476 * The default callback for AVCodecContext.get_buffer2(). It is made public so
3477 * it can be called by custom get_buffer2() implementations for decoders without
3478 * AV_CODEC_CAP_DR1 set.
3480 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
3483 * Modify width and height values so that they will result in a memory
3484 * buffer that is acceptable for the codec if you do not use any horizontal
3487 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
3489 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
3492 * Modify width and height values so that they will result in a memory
3493 * buffer that is acceptable for the codec if you also ensure that all
3494 * line sizes are a multiple of the respective linesize_align[i].
3496 * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
3498 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
3499 int linesize_align[AV_NUM_DATA_POINTERS]);
3502 * Converts AVChromaLocation to swscale x/y chroma position.
3504 * The positions represent the chroma (0,0) position in a coordinates system
3505 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3507 * @param xpos horizontal chroma sample position
3508 * @param ypos vertical chroma sample position
3510 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
3513 * Converts swscale x/y chroma position to AVChromaLocation.
3515 * The positions represent the chroma (0,0) position in a coordinates system
3516 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3518 * @param xpos horizontal chroma sample position
3519 * @param ypos vertical chroma sample position
3521 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
3524 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
3526 * Some decoders may support multiple frames in a single AVPacket. Such
3527 * decoders would then just decode the first frame and the return value would be
3528 * less than the packet size. In this case, avcodec_decode_audio4 has to be
3529 * called again with an AVPacket containing the remaining data in order to
3530 * decode the second frame, etc... Even if no frames are returned, the packet
3531 * needs to be fed to the decoder with remaining data until it is completely
3532 * consumed or an error occurs.
3534 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
3535 * and output. This means that for some packets they will not immediately
3536 * produce decoded output and need to be flushed at the end of decoding to get
3537 * all the decoded data. Flushing is done by calling this function with packets
3538 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3539 * returning samples. It is safe to flush even those decoders that are not
3540 * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
3542 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
3543 * larger than the actual read bytes because some optimized bitstream
3544 * readers read 32 or 64 bits at once and could read over the end.
3546 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3547 * before packets may be fed to the decoder.
3549 * @param avctx the codec context
3550 * @param[out] frame The AVFrame in which to store decoded audio samples.
3551 * The decoder will allocate a buffer for the decoded frame by
3552 * calling the AVCodecContext.get_buffer2() callback.
3553 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3554 * reference counted and the returned reference belongs to the
3555 * caller. The caller must release the frame using av_frame_unref()
3556 * when the frame is no longer needed. The caller may safely write
3557 * to the frame if av_frame_is_writable() returns 1.
3558 * When AVCodecContext.refcounted_frames is set to 0, the returned
3559 * reference belongs to the decoder and is valid only until the
3560 * next call to this function or until closing or flushing the
3561 * decoder. The caller may not write to it.
3562 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
3563 * non-zero. Note that this field being set to zero
3564 * does not mean that an error has occurred. For
3565 * decoders with AV_CODEC_CAP_DELAY set, no given decode
3566 * call is guaranteed to produce a frame.
3567 * @param[in] avpkt The input AVPacket containing the input buffer.
3568 * At least avpkt->data and avpkt->size should be set. Some
3569 * decoders might also require additional fields to be set.
3570 * @return A negative error code is returned if an error occurred during
3571 * decoding, otherwise the number of bytes consumed from the input
3572 * AVPacket is returned.
3574 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
3576 attribute_deprecated
3577 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
3578 int *got_frame_ptr, const AVPacket *avpkt);
3581 * Decode the video frame of size avpkt->size from avpkt->data into picture.
3582 * Some decoders may support multiple frames in a single AVPacket, such
3583 * decoders would then just decode the first frame.
3585 * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
3586 * the actual read bytes because some optimized bitstream readers read 32 or 64
3587 * bits at once and could read over the end.
3589 * @warning The end of the input buffer buf should be set to 0 to ensure that
3590 * no overreading happens for damaged MPEG streams.
3592 * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
3593 * between input and output, these need to be fed with avpkt->data=NULL,
3594 * avpkt->size=0 at the end to return the remaining frames.
3596 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3597 * before packets may be fed to the decoder.
3599 * @param avctx the codec context
3600 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
3601 * Use av_frame_alloc() to get an AVFrame. The codec will
3602 * allocate memory for the actual bitmap by calling the
3603 * AVCodecContext.get_buffer2() callback.
3604 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3605 * reference counted and the returned reference belongs to the
3606 * caller. The caller must release the frame using av_frame_unref()
3607 * when the frame is no longer needed. The caller may safely write
3608 * to the frame if av_frame_is_writable() returns 1.
3609 * When AVCodecContext.refcounted_frames is set to 0, the returned
3610 * reference belongs to the decoder and is valid only until the
3611 * next call to this function or until closing or flushing the
3612 * decoder. The caller may not write to it.
3614 * @param[in] avpkt The input AVPacket containing the input buffer.
3615 * You can create such packet with av_init_packet() and by then setting
3616 * data and size, some decoders might in addition need other fields like
3617 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
3619 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
3620 * @return On error a negative value is returned, otherwise the number of bytes
3621 * used or zero if no frame could be decompressed.
3623 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
3625 attribute_deprecated
3626 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
3627 int *got_picture_ptr,
3628 const AVPacket *avpkt);
3631 * Decode a subtitle message.
3632 * Return a negative value on error, otherwise return the number of bytes used.
3633 * If no subtitle could be decompressed, got_sub_ptr is zero.
3634 * Otherwise, the subtitle is stored in *sub.
3635 * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
3636 * simplicity, because the performance difference is expected to be negligible
3637 * and reusing a get_buffer written for video codecs would probably perform badly
3638 * due to a potentially very different allocation pattern.
3640 * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
3641 * and output. This means that for some packets they will not immediately
3642 * produce decoded output and need to be flushed at the end of decoding to get
3643 * all the decoded data. Flushing is done by calling this function with packets
3644 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3645 * returning subtitles. It is safe to flush even those decoders that are not
3646 * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
3648 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3649 * before packets may be fed to the decoder.
3651 * @param avctx the codec context
3652 * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
3653 * must be freed with avsubtitle_free if *got_sub_ptr is set.
3654 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
3655 * @param[in] avpkt The input AVPacket containing the input buffer.
3657 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
3662 * Supply raw packet data as input to a decoder.
3664 * Internally, this call will copy relevant AVCodecContext fields, which can
3665 * influence decoding per-packet, and apply them when the packet is actually
3666 * decoded. (For example AVCodecContext.skip_frame, which might direct the
3667 * decoder to drop the frame contained by the packet sent with this function.)
3669 * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
3670 * larger than the actual read bytes because some optimized bitstream
3671 * readers read 32 or 64 bits at once and could read over the end.
3673 * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
3674 * on the same AVCodecContext. It will return unexpected results now
3675 * or in future libavcodec versions.
3677 * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
3678 * before packets may be fed to the decoder.
3680 * @param avctx codec context
3681 * @param[in] avpkt The input AVPacket. Usually, this will be a single video
3682 * frame, or several complete audio frames.
3683 * Ownership of the packet remains with the caller, and the
3684 * decoder will not write to the packet. The decoder may create
3685 * a reference to the packet data (or copy it if the packet is
3686 * not reference-counted).
3687 * Unlike with older APIs, the packet is always fully consumed,
3688 * and if it contains multiple frames (e.g. some audio codecs),
3689 * will require you to call avcodec_receive_frame() multiple
3690 * times afterwards before you can send a new packet.
3691 * It can be NULL (or an AVPacket with data set to NULL and
3692 * size set to 0); in this case, it is considered a flush
3693 * packet, which signals the end of the stream. Sending the
3694 * first flush packet will return success. Subsequent ones are
3695 * unnecessary and will return AVERROR_EOF. If the decoder
3696 * still has frames buffered, it will return them after sending
3699 * @return 0 on success, otherwise negative error code:
3700 * AVERROR(EAGAIN): input is not accepted in the current state - user
3701 * must read output with avcodec_receive_frame() (once
3702 * all output is read, the packet should be resent, and
3703 * the call will not fail with EAGAIN).
3704 * AVERROR_EOF: the decoder has been flushed, and no new packets can
3705 * be sent to it (also returned if more than 1 flush
3707 * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
3708 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
3709 * other errors: legitimate decoding errors
3711 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
3714 * Return decoded output data from a decoder.
3716 * @param avctx codec context
3717 * @param frame This will be set to a reference-counted video or audio
3718 * frame (depending on the decoder type) allocated by the
3719 * decoder. Note that the function will always call
3720 * av_frame_unref(frame) before doing anything else.
3723 * 0: success, a frame was returned
3724 * AVERROR(EAGAIN): output is not available in this state - user must try
3726 * AVERROR_EOF: the decoder has been fully flushed, and there will be
3727 * no more output frames
3728 * AVERROR(EINVAL): codec not opened, or it is an encoder
3729 * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
3730 * with respect to first decoded frame. Applicable
3731 * when flag AV_CODEC_FLAG_DROPCHANGED is set.
3732 * other negative values: legitimate decoding errors
3734 int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
3737 * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
3738 * to retrieve buffered output packets.
3740 * @param avctx codec context
3741 * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
3742 * Ownership of the frame remains with the caller, and the
3743 * encoder will not write to the frame. The encoder may create
3744 * a reference to the frame data (or copy it if the frame is
3745 * not reference-counted).
3746 * It can be NULL, in which case it is considered a flush
3747 * packet. This signals the end of the stream. If the encoder
3748 * still has packets buffered, it will return them after this
3749 * call. Once flushing mode has been entered, additional flush
3750 * packets are ignored, and sending frames will return
3754 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
3755 * can have any number of samples.
3756 * If it is not set, frame->nb_samples must be equal to
3757 * avctx->frame_size for all frames except the last.
3758 * The final frame may be smaller than avctx->frame_size.
3759 * @return 0 on success, otherwise negative error code:
3760 * AVERROR(EAGAIN): input is not accepted in the current state - user
3761 * must read output with avcodec_receive_packet() (once
3762 * all output is read, the packet should be resent, and
3763 * the call will not fail with EAGAIN).
3764 * AVERROR_EOF: the encoder has been flushed, and no new frames can
3766 * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
3767 * decoder, or requires flush
3768 * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
3769 * other errors: legitimate encoding errors
3771 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
3774 * Read encoded data from the encoder.
3776 * @param avctx codec context
3777 * @param avpkt This will be set to a reference-counted packet allocated by the
3778 * encoder. Note that the function will always call
3779 * av_packet_unref(avpkt) before doing anything else.
3780 * @return 0 on success, otherwise negative error code:
3781 * AVERROR(EAGAIN): output is not available in the current state - user
3782 * must try to send input
3783 * AVERROR_EOF: the encoder has been fully flushed, and there will be
3784 * no more output packets
3785 * AVERROR(EINVAL): codec not opened, or it is a decoder
3786 * other errors: legitimate encoding errors
3788 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
3791 * Create and return a AVHWFramesContext with values adequate for hardware
3792 * decoding. This is meant to get called from the get_format callback, and is
3793 * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
3794 * This API is for decoding with certain hardware acceleration modes/APIs only.
3796 * The returned AVHWFramesContext is not initialized. The caller must do this
3797 * with av_hwframe_ctx_init().
3799 * Calling this function is not a requirement, but makes it simpler to avoid
3800 * codec or hardware API specific details when manually allocating frames.
3802 * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
3803 * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
3804 * it unnecessary to call this function or having to care about
3805 * AVHWFramesContext initialization at all.
3807 * There are a number of requirements for calling this function:
3809 * - It must be called from get_format with the same avctx parameter that was
3810 * passed to get_format. Calling it outside of get_format is not allowed, and
3811 * can trigger undefined behavior.
3812 * - The function is not always supported (see description of return values).
3813 * Even if this function returns successfully, hwaccel initialization could
3814 * fail later. (The degree to which implementations check whether the stream
3815 * is actually supported varies. Some do this check only after the user's
3816 * get_format callback returns.)
3817 * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
3818 * user decides to use a AVHWFramesContext prepared with this API function,
3819 * the user must return the same hw_pix_fmt from get_format.
3820 * - The device_ref passed to this function must support the given hw_pix_fmt.
3821 * - After calling this API function, it is the user's responsibility to
3822 * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
3823 * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
3824 * before returning from get_format (this is implied by the normal
3825 * AVCodecContext.hw_frames_ctx API rules).
3826 * - The AVHWFramesContext parameters may change every time time get_format is
3827 * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
3828 * you are inherently required to go through this process again on every
3830 * - It is perfectly possible to call this function without actually using
3831 * the resulting AVHWFramesContext. One use-case might be trying to reuse a
3832 * previously initialized AVHWFramesContext, and calling this API function
3833 * only to test whether the required frame parameters have changed.
3834 * - Fields that use dynamically allocated values of any kind must not be set
3835 * by the user unless setting them is explicitly allowed by the documentation.
3836 * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
3837 * the new free callback must call the potentially set previous free callback.
3838 * This API call may set any dynamically allocated fields, including the free
3841 * The function will set at least the following fields on AVHWFramesContext
3842 * (potentially more, depending on hwaccel API):
3844 * - All fields set by av_hwframe_ctx_alloc().
3845 * - Set the format field to hw_pix_fmt.
3846 * - Set the sw_format field to the most suited and most versatile format. (An
3847 * implication is that this will prefer generic formats over opaque formats
3848 * with arbitrary restrictions, if possible.)
3849 * - Set the width/height fields to the coded frame size, rounded up to the
3850 * API-specific minimum alignment.
3851 * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
3852 * field to the number of maximum reference surfaces possible with the codec,
3853 * plus 1 surface for the user to work (meaning the user can safely reference
3854 * at most 1 decoded surface at a time), plus additional buffering introduced
3855 * by frame threading. If the hwaccel does not require pre-allocation, the
3856 * field is left to 0, and the decoder will allocate new surfaces on demand
3858 * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
3861 * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
3862 * with basic frame parameters set.
3864 * The function is stateless, and does not change the AVCodecContext or the
3865 * device_ref AVHWDeviceContext.
3867 * @param avctx The context which is currently calling get_format, and which
3868 * implicitly contains all state needed for filling the returned
3869 * AVHWFramesContext properly.
3870 * @param device_ref A reference to the AVHWDeviceContext describing the device
3871 * which will be used by the hardware decoder.
3872 * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
3873 * @param out_frames_ref On success, set to a reference to an _uninitialized_
3874 * AVHWFramesContext, created from the given device_ref.
3875 * Fields will be set to values required for decoding.
3876 * Not changed if an error is returned.
3877 * @return zero on success, a negative value on error. The following error codes
3878 * have special semantics:
3879 * AVERROR(ENOENT): the decoder does not support this functionality. Setup
3880 * is always manual, or it is a decoder which does not
3881 * support setting AVCodecContext.hw_frames_ctx at all,
3882 * or it is a software format.
3883 * AVERROR(EINVAL): it is known that hardware decoding is not supported for
3884 * this configuration, or the device_ref is not supported
3885 * for the hwaccel referenced by hw_pix_fmt.
3887 int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
3888 AVBufferRef *device_ref,
3889 enum AVPixelFormat hw_pix_fmt,
3890 AVBufferRef **out_frames_ref);
3895 * @defgroup lavc_parsing Frame parsing
3899 enum AVPictureStructure {
3900 AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
3901 AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
3902 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
3903 AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
3906 typedef struct AVCodecParserContext {
3908 struct AVCodecParser *parser;
3909 int64_t frame_offset; /* offset of the current frame */
3910 int64_t cur_offset; /* current offset
3911 (incremented by each av_parser_parse()) */
3912 int64_t next_frame_offset; /* offset of the next frame */
3914 int pict_type; /* XXX: Put it back in AVCodecContext. */
3916 * This field is used for proper frame duration computation in lavf.
3917 * It signals, how much longer the frame duration of the current frame
3918 * is compared to normal frame duration.
3920 * frame_duration = (1 + repeat_pict) * time_base
3922 * It is used by codecs like H.264 to display telecined material.
3924 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
3925 int64_t pts; /* pts of the current frame */
3926 int64_t dts; /* dts of the current frame */
3931 int fetch_timestamp;
3933 #define AV_PARSER_PTS_NB 4
3934 int cur_frame_start_index;
3935 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
3936 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
3937 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
3940 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
3941 #define PARSER_FLAG_ONCE 0x0002
3942 /// Set if the parser has a valid file offset
3943 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
3944 #define PARSER_FLAG_USE_CODEC_TS 0x1000
3946 int64_t offset; ///< byte offset from starting packet start
3947 int64_t cur_frame_end[AV_PARSER_PTS_NB];
3950 * Set by parser to 1 for key frames and 0 for non-key frames.
3951 * It is initialized to -1, so if the parser doesn't set this flag,
3952 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
3957 #if FF_API_CONVERGENCE_DURATION
3959 * @deprecated unused
3961 attribute_deprecated
3962 int64_t convergence_duration;
3965 // Timestamp generation support:
3967 * Synchronization point for start of timestamp generation.
3969 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
3972 * For example, this corresponds to presence of H.264 buffering period
3978 * Offset of the current timestamp against last timestamp sync point in
3979 * units of AVCodecContext.time_base.
3981 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3982 * contain a valid timestamp offset.
3984 * Note that the timestamp of sync point has usually a nonzero
3985 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
3986 * the next frame after timestamp sync point will be usually 1.
3988 * For example, this corresponds to H.264 cpb_removal_delay.
3990 int dts_ref_dts_delta;
3993 * Presentation delay of current frame in units of AVCodecContext.time_base.
3995 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3996 * contain valid non-negative timestamp delta (presentation time of a frame
3997 * must not lie in the past).
3999 * This delay represents the difference between decoding and presentation
4000 * time of the frame.
4002 * For example, this corresponds to H.264 dpb_output_delay.
4007 * Position of the packet in file.
4009 * Analogous to cur_frame_pts/dts
4011 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
4014 * Byte position of currently parsed frame in stream.
4019 * Previous frame byte position.
4024 * Duration of the current frame.
4025 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
4026 * For all other types, this is in units of AVCodecContext.time_base.
4030 enum AVFieldOrder field_order;
4033 * Indicate whether a picture is coded as a frame, top field or bottom field.
4035 * For example, H.264 field_pic_flag equal to 0 corresponds to
4036 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
4037 * equal to 1 and bottom_field_flag equal to 0 corresponds to
4038 * AV_PICTURE_STRUCTURE_TOP_FIELD.
4040 enum AVPictureStructure picture_structure;
4043 * Picture number incremented in presentation or output order.
4044 * This field may be reinitialized at the first picture of a new sequence.
4046 * For example, this corresponds to H.264 PicOrderCnt.
4048 int output_picture_number;
4051 * Dimensions of the decoded video intended for presentation.
4057 * Dimensions of the coded video.
4063 * The format of the coded data, corresponds to enum AVPixelFormat for video
4064 * and for enum AVSampleFormat for audio.
4066 * Note that a decoder can have considerable freedom in how exactly it
4067 * decodes the data, so the format reported here might be different from the
4068 * one returned by a decoder.
4071 } AVCodecParserContext;
4073 typedef struct AVCodecParser {
4074 int codec_ids[5]; /* several codec IDs are permitted */
4076 int (*parser_init)(AVCodecParserContext *s);
4077 /* This callback never returns an error, a negative value means that
4078 * the frame start was in a previous packet. */
4079 int (*parser_parse)(AVCodecParserContext *s,
4080 AVCodecContext *avctx,
4081 const uint8_t **poutbuf, int *poutbuf_size,
4082 const uint8_t *buf, int buf_size);
4083 void (*parser_close)(AVCodecParserContext *s);
4084 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
4085 struct AVCodecParser *next;
4089 * Iterate over all registered codec parsers.
4091 * @param opaque a pointer where libavcodec will store the iteration state. Must
4092 * point to NULL to start the iteration.
4094 * @return the next registered codec parser or NULL when the iteration is
4097 const AVCodecParser *av_parser_iterate(void **opaque);
4099 attribute_deprecated
4100 AVCodecParser *av_parser_next(const AVCodecParser *c);
4102 attribute_deprecated
4103 void av_register_codec_parser(AVCodecParser *parser);
4104 AVCodecParserContext *av_parser_init(int codec_id);
4109 * @param s parser context.
4110 * @param avctx codec context.
4111 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
4112 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
4113 * @param buf input buffer.
4114 * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
4115 size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
4116 To signal EOF, this should be 0 (so that the last frame
4118 * @param pts input presentation timestamp.
4119 * @param dts input decoding timestamp.
4120 * @param pos input byte position in stream.
4121 * @return the number of bytes of the input bitstream used.
4126 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
4133 * decode_frame(data, size);
4137 int av_parser_parse2(AVCodecParserContext *s,
4138 AVCodecContext *avctx,
4139 uint8_t **poutbuf, int *poutbuf_size,
4140 const uint8_t *buf, int buf_size,
4141 int64_t pts, int64_t dts,
4145 * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
4146 * @deprecated use AVBitStreamFilter
4148 int av_parser_change(AVCodecParserContext *s,
4149 AVCodecContext *avctx,
4150 uint8_t **poutbuf, int *poutbuf_size,
4151 const uint8_t *buf, int buf_size, int keyframe);
4152 void av_parser_close(AVCodecParserContext *s);
4160 * @addtogroup lavc_encoding
4165 * Find a registered encoder with a matching codec ID.
4167 * @param id AVCodecID of the requested encoder
4168 * @return An encoder if one was found, NULL otherwise.
4170 AVCodec *avcodec_find_encoder(enum AVCodecID id);
4173 * Find a registered encoder with the specified name.
4175 * @param name name of the requested encoder
4176 * @return An encoder if one was found, NULL otherwise.
4178 AVCodec *avcodec_find_encoder_by_name(const char *name);
4181 * Encode a frame of audio.
4183 * Takes input samples from frame and writes the next output packet, if
4184 * available, to avpkt. The output packet does not necessarily contain data for
4185 * the most recent frame, as encoders can delay, split, and combine input frames
4186 * internally as needed.
4188 * @param avctx codec context
4189 * @param avpkt output AVPacket.
4190 * The user can supply an output buffer by setting
4191 * avpkt->data and avpkt->size prior to calling the
4192 * function, but if the size of the user-provided data is not
4193 * large enough, encoding will fail. If avpkt->data and
4194 * avpkt->size are set, avpkt->destruct must also be set. All
4195 * other AVPacket fields will be reset by the encoder using
4196 * av_init_packet(). If avpkt->data is NULL, the encoder will
4197 * allocate it. The encoder will set avpkt->size to the size
4198 * of the output packet.
4200 * If this function fails or produces no output, avpkt will be
4201 * freed using av_packet_unref().
4202 * @param[in] frame AVFrame containing the raw audio data to be encoded.
4203 * May be NULL when flushing an encoder that has the
4204 * AV_CODEC_CAP_DELAY capability set.
4205 * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4206 * can have any number of samples.
4207 * If it is not set, frame->nb_samples must be equal to
4208 * avctx->frame_size for all frames except the last.
4209 * The final frame may be smaller than avctx->frame_size.
4210 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4211 * output packet is non-empty, and to 0 if it is
4212 * empty. If the function returns an error, the
4213 * packet can be assumed to be invalid, and the
4214 * value of got_packet_ptr is undefined and should
4216 * @return 0 on success, negative error code on failure
4218 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
4220 attribute_deprecated
4221 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
4222 const AVFrame *frame, int *got_packet_ptr);
4225 * Encode a frame of video.
4227 * Takes input raw video data from frame and writes the next output packet, if
4228 * available, to avpkt. The output packet does not necessarily contain data for
4229 * the most recent frame, as encoders can delay and reorder input frames
4230 * internally as needed.
4232 * @param avctx codec context
4233 * @param avpkt output AVPacket.
4234 * The user can supply an output buffer by setting
4235 * avpkt->data and avpkt->size prior to calling the
4236 * function, but if the size of the user-provided data is not
4237 * large enough, encoding will fail. All other AVPacket fields
4238 * will be reset by the encoder using av_init_packet(). If
4239 * avpkt->data is NULL, the encoder will allocate it.
4240 * The encoder will set avpkt->size to the size of the
4241 * output packet. The returned data (if any) belongs to the
4242 * caller, he is responsible for freeing it.
4244 * If this function fails or produces no output, avpkt will be
4245 * freed using av_packet_unref().
4246 * @param[in] frame AVFrame containing the raw video data to be encoded.
4247 * May be NULL when flushing an encoder that has the
4248 * AV_CODEC_CAP_DELAY capability set.
4249 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4250 * output packet is non-empty, and to 0 if it is
4251 * empty. If the function returns an error, the
4252 * packet can be assumed to be invalid, and the
4253 * value of got_packet_ptr is undefined and should
4255 * @return 0 on success, negative error code on failure
4257 * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
4259 attribute_deprecated
4260 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
4261 const AVFrame *frame, int *got_packet_ptr);
4263 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4264 const AVSubtitle *sub);
4271 #if FF_API_AVPICTURE
4273 * @addtogroup lavc_picture
4278 * @deprecated unused
4280 attribute_deprecated
4281 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
4284 * @deprecated unused
4286 attribute_deprecated
4287 void avpicture_free(AVPicture *picture);
4290 * @deprecated use av_image_fill_arrays() instead.
4292 attribute_deprecated
4293 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
4294 enum AVPixelFormat pix_fmt, int width, int height);
4297 * @deprecated use av_image_copy_to_buffer() instead.
4299 attribute_deprecated
4300 int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
4301 int width, int height,
4302 unsigned char *dest, int dest_size);
4305 * @deprecated use av_image_get_buffer_size() instead.
4307 attribute_deprecated
4308 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
4311 * @deprecated av_image_copy() instead.
4313 attribute_deprecated
4314 void av_picture_copy(AVPicture *dst, const AVPicture *src,
4315 enum AVPixelFormat pix_fmt, int width, int height);
4318 * @deprecated unused
4320 attribute_deprecated
4321 int av_picture_crop(AVPicture *dst, const AVPicture *src,
4322 enum AVPixelFormat pix_fmt, int top_band, int left_band);
4325 * @deprecated unused
4327 attribute_deprecated
4328 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
4329 int padtop, int padbottom, int padleft, int padright, int *color);
4337 * @defgroup lavc_misc Utility functions
4340 * Miscellaneous utility functions related to both encoding and decoding
4346 * @defgroup lavc_misc_pixfmt Pixel formats
4348 * Functions for working with pixel formats.
4352 #if FF_API_GETCHROMA
4354 * @deprecated Use av_pix_fmt_get_chroma_sub_sample
4357 attribute_deprecated
4358 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
4362 * Return a value representing the fourCC code associated to the
4363 * pixel format pix_fmt, or 0 if no associated fourCC code can be
4366 unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
4369 * @deprecated see av_get_pix_fmt_loss()
4371 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
4375 * Find the best pixel format to convert to given a certain source pixel
4376 * format. When converting from one pixel format to another, information loss
4377 * may occur. For example, when converting from RGB24 to GRAY, the color
4378 * information will be lost. Similarly, other losses occur when converting from
4379 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
4380 * the given pixel formats should be used to suffer the least amount of loss.
4381 * The pixel formats from which it chooses one, are determined by the
4382 * pix_fmt_list parameter.
4385 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
4386 * @param[in] src_pix_fmt source pixel format
4387 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4388 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
4389 * @return The best pixel format to convert to or -1 if none was found.
4391 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
4392 enum AVPixelFormat src_pix_fmt,
4393 int has_alpha, int *loss_ptr);
4396 * @deprecated see av_find_best_pix_fmt_of_2()
4398 enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4399 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4401 attribute_deprecated
4402 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4403 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4405 enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
4411 #if FF_API_TAG_STRING
4413 * Put a string representing the codec tag codec_tag in buf.
4415 * @param buf buffer to place codec tag in
4416 * @param buf_size size in bytes of buf
4417 * @param codec_tag codec tag to assign
4418 * @return the length of the string that would have been generated if
4419 * enough space had been available, excluding the trailing null
4421 * @deprecated see av_fourcc_make_string() and av_fourcc2str().
4423 attribute_deprecated
4424 size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
4427 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
4430 * Return a name for the specified profile, if available.
4432 * @param codec the codec that is searched for the given profile
4433 * @param profile the profile value for which a name is requested
4434 * @return A name for the profile if found, NULL otherwise.
4436 const char *av_get_profile_name(const AVCodec *codec, int profile);
4439 * Return a name for the specified profile, if available.
4441 * @param codec_id the ID of the codec to which the requested profile belongs
4442 * @param profile the profile value for which a name is requested
4443 * @return A name for the profile if found, NULL otherwise.
4445 * @note unlike av_get_profile_name(), which searches a list of profiles
4446 * supported by a specific decoder or encoder implementation, this
4447 * function searches the list of profiles from the AVCodecDescriptor
4449 const char *avcodec_profile_name(enum AVCodecID codec_id, int profile);
4451 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
4452 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
4453 //FIXME func typedef
4456 * Fill AVFrame audio data and linesize pointers.
4458 * The buffer buf must be a preallocated buffer with a size big enough
4459 * to contain the specified samples amount. The filled AVFrame data
4460 * pointers will point to this buffer.
4462 * AVFrame extended_data channel pointers are allocated if necessary for
4465 * @param frame the AVFrame
4466 * frame->nb_samples must be set prior to calling the
4467 * function. This function fills in frame->data,
4468 * frame->extended_data, frame->linesize[0].
4469 * @param nb_channels channel count
4470 * @param sample_fmt sample format
4471 * @param buf buffer to use for frame data
4472 * @param buf_size size of buffer
4473 * @param align plane size sample alignment (0 = default)
4474 * @return >=0 on success, negative error code on failure
4475 * @todo return the size in bytes required to store the samples in
4476 * case of success, at the next libavutil bump
4478 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
4479 enum AVSampleFormat sample_fmt, const uint8_t *buf,
4480 int buf_size, int align);
4483 * Reset the internal codec state / flush internal buffers. Should be called
4484 * e.g. when seeking or when switching to a different stream.
4486 * @note for decoders, when refcounted frames are not used
4487 * (i.e. avctx->refcounted_frames is 0), this invalidates the frames previously
4488 * returned from the decoder. When refcounted frames are used, the decoder just
4489 * releases any references it might keep internally, but the caller's reference
4492 * @note for encoders, this function will only do something if the encoder
4493 * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
4494 * will drain any remaining packets, and can then be re-used for a different
4495 * stream (as opposed to sending a null frame which will leave the encoder
4496 * in a permanent EOF state after draining). This can be desirable if the
4497 * cost of tearing down and replacing the encoder instance is high.
4499 void avcodec_flush_buffers(AVCodecContext *avctx);
4502 * Return codec bits per sample.
4504 * @param[in] codec_id the codec
4505 * @return Number of bits per sample or zero if unknown for the given codec.
4507 int av_get_bits_per_sample(enum AVCodecID codec_id);
4510 * Return the PCM codec associated with a sample format.
4511 * @param be endianness, 0 for little, 1 for big,
4512 * -1 (or anything else) for native
4513 * @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
4515 enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
4518 * Return codec bits per sample.
4519 * Only return non-zero if the bits per sample is exactly correct, not an
4522 * @param[in] codec_id the codec
4523 * @return Number of bits per sample or zero if unknown for the given codec.
4525 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
4528 * Return audio frame duration.
4530 * @param avctx codec context
4531 * @param frame_bytes size of the frame, or 0 if unknown
4532 * @return frame duration, in samples, if known. 0 if not able to
4535 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
4538 * This function is the same as av_get_audio_frame_duration(), except it works
4539 * with AVCodecParameters instead of an AVCodecContext.
4541 int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
4544 typedef struct AVBitStreamFilterContext {
4546 const struct AVBitStreamFilter *filter;
4547 AVCodecParserContext *parser;
4548 struct AVBitStreamFilterContext *next;
4550 * Internal default arguments, used if NULL is passed to av_bitstream_filter_filter().
4551 * Not for access by library users.
4554 } AVBitStreamFilterContext;
4557 typedef struct AVBSFInternal AVBSFInternal;
4560 * The bitstream filter state.
4562 * This struct must be allocated with av_bsf_alloc() and freed with
4565 * The fields in the struct will only be changed (by the caller or by the
4566 * filter) as described in their documentation, and are to be considered
4567 * immutable otherwise.
4569 typedef struct AVBSFContext {
4571 * A class for logging and AVOptions
4573 const AVClass *av_class;
4576 * The bitstream filter this context is an instance of.
4578 const struct AVBitStreamFilter *filter;
4581 * Opaque libavcodec internal data. Must not be touched by the caller in any
4584 AVBSFInternal *internal;
4587 * Opaque filter-specific private data. If filter->priv_class is non-NULL,
4588 * this is an AVOptions-enabled struct.
4593 * Parameters of the input stream. This field is allocated in
4594 * av_bsf_alloc(), it needs to be filled by the caller before
4597 AVCodecParameters *par_in;
4600 * Parameters of the output stream. This field is allocated in
4601 * av_bsf_alloc(), it is set by the filter in av_bsf_init().
4603 AVCodecParameters *par_out;
4606 * The timebase used for the timestamps of the input packets. Set by the
4607 * caller before av_bsf_init().
4609 AVRational time_base_in;
4612 * The timebase used for the timestamps of the output packets. Set by the
4613 * filter in av_bsf_init().
4615 AVRational time_base_out;
4618 typedef struct AVBitStreamFilter {
4622 * A list of codec ids supported by the filter, terminated by
4624 * May be NULL, in that case the bitstream filter works with any codec id.
4626 const enum AVCodecID *codec_ids;
4629 * A class for the private data, used to declare bitstream filter private
4630 * AVOptions. This field is NULL for bitstream filters that do not declare
4633 * If this field is non-NULL, the first member of the filter private data
4634 * must be a pointer to AVClass, which will be set by libavcodec generic
4635 * code to this class.
4637 const AVClass *priv_class;
4639 /*****************************************************************
4640 * No fields below this line are part of the public API. They
4641 * may not be used outside of libavcodec and can be changed and
4643 * New public fields should be added right above.
4644 *****************************************************************
4648 int (*init)(AVBSFContext *ctx);
4649 int (*filter)(AVBSFContext *ctx, AVPacket *pkt);
4650 void (*close)(AVBSFContext *ctx);
4651 void (*flush)(AVBSFContext *ctx);
4652 } AVBitStreamFilter;
4656 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4657 * is deprecated. Use the new bitstream filtering API (using AVBSFContext).
4659 attribute_deprecated
4660 void av_register_bitstream_filter(AVBitStreamFilter *bsf);
4662 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4663 * is deprecated. Use av_bsf_get_by_name(), av_bsf_alloc(), and av_bsf_init()
4664 * from the new bitstream filtering API (using AVBSFContext).
4666 attribute_deprecated
4667 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
4669 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4670 * is deprecated. Use av_bsf_send_packet() and av_bsf_receive_packet() from the
4671 * new bitstream filtering API (using AVBSFContext).
4673 attribute_deprecated
4674 int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
4675 AVCodecContext *avctx, const char *args,
4676 uint8_t **poutbuf, int *poutbuf_size,
4677 const uint8_t *buf, int buf_size, int keyframe);
4679 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4680 * is deprecated. Use av_bsf_free() from the new bitstream filtering API (using
4683 attribute_deprecated
4684 void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
4686 * @deprecated the old bitstream filtering API (using AVBitStreamFilterContext)
4687 * is deprecated. Use av_bsf_iterate() from the new bitstream filtering API (using
4690 attribute_deprecated
4691 const AVBitStreamFilter *av_bitstream_filter_next(const AVBitStreamFilter *f);
4695 * @return a bitstream filter with the specified name or NULL if no such
4696 * bitstream filter exists.
4698 const AVBitStreamFilter *av_bsf_get_by_name(const char *name);
4701 * Iterate over all registered bitstream filters.
4703 * @param opaque a pointer where libavcodec will store the iteration state. Must
4704 * point to NULL to start the iteration.
4706 * @return the next registered bitstream filter or NULL when the iteration is
4709 const AVBitStreamFilter *av_bsf_iterate(void **opaque);
4711 attribute_deprecated
4712 const AVBitStreamFilter *av_bsf_next(void **opaque);
4716 * Allocate a context for a given bitstream filter. The caller must fill in the
4717 * context parameters as described in the documentation and then call
4718 * av_bsf_init() before sending any data to the filter.
4720 * @param filter the filter for which to allocate an instance.
4721 * @param ctx a pointer into which the pointer to the newly-allocated context
4722 * will be written. It must be freed with av_bsf_free() after the
4723 * filtering is done.
4725 * @return 0 on success, a negative AVERROR code on failure
4727 int av_bsf_alloc(const AVBitStreamFilter *filter, AVBSFContext **ctx);
4730 * Prepare the filter for use, after all the parameters and options have been
4733 int av_bsf_init(AVBSFContext *ctx);
4736 * Submit a packet for filtering.
4738 * After sending each packet, the filter must be completely drained by calling
4739 * av_bsf_receive_packet() repeatedly until it returns AVERROR(EAGAIN) or
4742 * @param pkt the packet to filter. The bitstream filter will take ownership of
4743 * the packet and reset the contents of pkt. pkt is not touched if an error occurs.
4744 * If pkt is empty (i.e. NULL, or pkt->data is NULL and pkt->side_data_elems zero),
4745 * it signals the end of the stream (i.e. no more non-empty packets will be sent;
4746 * sending more empty packets does nothing) and will cause the filter to output
4747 * any packets it may have buffered internally.
4749 * @return 0 on success, a negative AVERROR on error. This function never fails if
4752 int av_bsf_send_packet(AVBSFContext *ctx, AVPacket *pkt);
4755 * Retrieve a filtered packet.
4757 * @param[out] pkt this struct will be filled with the contents of the filtered
4758 * packet. It is owned by the caller and must be freed using
4759 * av_packet_unref() when it is no longer needed.
4760 * This parameter should be "clean" (i.e. freshly allocated
4761 * with av_packet_alloc() or unreffed with av_packet_unref())
4762 * when this function is called. If this function returns
4763 * successfully, the contents of pkt will be completely
4764 * overwritten by the returned data. On failure, pkt is not
4767 * @return 0 on success. AVERROR(EAGAIN) if more packets need to be sent to the
4768 * filter (using av_bsf_send_packet()) to get more output. AVERROR_EOF if there
4769 * will be no further output from the filter. Another negative AVERROR value if
4772 * @note one input packet may result in several output packets, so after sending
4773 * a packet with av_bsf_send_packet(), this function needs to be called
4774 * repeatedly until it stops returning 0. It is also possible for a filter to
4775 * output fewer packets than were sent to it, so this function may return
4776 * AVERROR(EAGAIN) immediately after a successful av_bsf_send_packet() call.
4778 int av_bsf_receive_packet(AVBSFContext *ctx, AVPacket *pkt);
4781 * Reset the internal bitstream filter state / flush internal buffers.
4783 void av_bsf_flush(AVBSFContext *ctx);
4786 * Free a bitstream filter context and everything associated with it; write NULL
4787 * into the supplied pointer.
4789 void av_bsf_free(AVBSFContext **ctx);
4792 * Get the AVClass for AVBSFContext. It can be used in combination with
4793 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4795 * @see av_opt_find().
4797 const AVClass *av_bsf_get_class(void);
4800 * Structure for chain/list of bitstream filters.
4801 * Empty list can be allocated by av_bsf_list_alloc().
4803 typedef struct AVBSFList AVBSFList;
4806 * Allocate empty list of bitstream filters.
4807 * The list must be later freed by av_bsf_list_free()
4808 * or finalized by av_bsf_list_finalize().
4810 * @return Pointer to @ref AVBSFList on success, NULL in case of failure
4812 AVBSFList *av_bsf_list_alloc(void);
4815 * Free list of bitstream filters.
4817 * @param lst Pointer to pointer returned by av_bsf_list_alloc()
4819 void av_bsf_list_free(AVBSFList **lst);
4822 * Append bitstream filter to the list of bitstream filters.
4824 * @param lst List to append to
4825 * @param bsf Filter context to be appended
4827 * @return >=0 on success, negative AVERROR in case of failure
4829 int av_bsf_list_append(AVBSFList *lst, AVBSFContext *bsf);
4832 * Construct new bitstream filter context given it's name and options
4833 * and append it to the list of bitstream filters.
4835 * @param lst List to append to
4836 * @param bsf_name Name of the bitstream filter
4837 * @param options Options for the bitstream filter, can be set to NULL
4839 * @return >=0 on success, negative AVERROR in case of failure
4841 int av_bsf_list_append2(AVBSFList *lst, const char * bsf_name, AVDictionary **options);
4843 * Finalize list of bitstream filters.
4845 * This function will transform @ref AVBSFList to single @ref AVBSFContext,
4846 * so the whole chain of bitstream filters can be treated as single filter
4847 * freshly allocated by av_bsf_alloc().
4848 * If the call is successful, @ref AVBSFList structure is freed and lst
4849 * will be set to NULL. In case of failure, caller is responsible for
4850 * freeing the structure by av_bsf_list_free()
4852 * @param lst Filter list structure to be transformed
4853 * @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
4854 * representing the chain of bitstream filters
4856 * @return >=0 on success, negative AVERROR in case of failure
4858 int av_bsf_list_finalize(AVBSFList **lst, AVBSFContext **bsf);
4861 * Parse string describing list of bitstream filters and create single
4862 * @ref AVBSFContext describing the whole chain of bitstream filters.
4863 * Resulting @ref AVBSFContext can be treated as any other @ref AVBSFContext freshly
4864 * allocated by av_bsf_alloc().
4866 * @param str String describing chain of bitstream filters in format
4867 * `bsf1[=opt1=val1:opt2=val2][,bsf2]`
4868 * @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
4869 * representing the chain of bitstream filters
4871 * @return >=0 on success, negative AVERROR in case of failure
4873 int av_bsf_list_parse_str(const char *str, AVBSFContext **bsf);
4876 * Get null/pass-through bitstream filter.
4878 * @param[out] bsf Pointer to be set to new instance of pass-through bitstream filter
4882 int av_bsf_get_null_filter(AVBSFContext **bsf);
4887 * Same behaviour av_fast_malloc but the buffer has additional
4888 * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
4890 * In addition the whole buffer will initially and after resizes
4891 * be 0-initialized so that no uninitialized data will ever appear.
4893 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
4896 * Same behaviour av_fast_padded_malloc except that buffer will always
4897 * be 0-initialized after call.
4899 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
4902 * Encode extradata length to a buffer. Used by xiph codecs.
4904 * @param s buffer to write to; must be at least (v/255+1) bytes long
4905 * @param v size of extradata in bytes
4906 * @return number of bytes written to the buffer.
4908 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
4910 #if FF_API_USER_VISIBLE_AVHWACCEL
4912 * Register the hardware accelerator hwaccel.
4914 * @deprecated This function doesn't do anything.
4916 attribute_deprecated
4917 void av_register_hwaccel(AVHWAccel *hwaccel);
4920 * If hwaccel is NULL, returns the first registered hardware accelerator,
4921 * if hwaccel is non-NULL, returns the next registered hardware accelerator
4922 * after hwaccel, or NULL if hwaccel is the last one.
4924 * @deprecated AVHWaccel structures contain no user-serviceable parts, so
4925 * this function should not be used.
4927 attribute_deprecated
4928 AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel);
4933 * Lock operation used by lockmgr
4935 * @deprecated Deprecated together with av_lockmgr_register().
4938 AV_LOCK_CREATE, ///< Create a mutex
4939 AV_LOCK_OBTAIN, ///< Lock the mutex
4940 AV_LOCK_RELEASE, ///< Unlock the mutex
4941 AV_LOCK_DESTROY, ///< Free mutex resources
4945 * Register a user provided lock manager supporting the operations
4946 * specified by AVLockOp. The "mutex" argument to the function points
4947 * to a (void *) where the lockmgr should store/get a pointer to a user
4948 * allocated mutex. It is NULL upon AV_LOCK_CREATE and equal to the
4949 * value left by the last call for all other ops. If the lock manager is
4950 * unable to perform the op then it should leave the mutex in the same
4951 * state as when it was called and return a non-zero value. However,
4952 * when called with AV_LOCK_DESTROY the mutex will always be assumed to
4953 * have been successfully destroyed. If av_lockmgr_register succeeds
4954 * it will return a non-negative value, if it fails it will return a
4955 * negative value and destroy all mutex and unregister all callbacks.
4956 * av_lockmgr_register is not thread-safe, it must be called from a
4957 * single thread before any calls which make use of locking are used.
4959 * @param cb User defined callback. av_lockmgr_register invokes calls
4960 * to this callback and the previously registered callback.
4961 * The callback will be used to create more than one mutex
4962 * each of which must be backed by its own underlying locking
4963 * mechanism (i.e. do not use a single static object to
4964 * implement your lock manager). If cb is set to NULL the
4965 * lockmgr will be unregistered.
4967 * @deprecated This function does nothing, and always returns 0. Be sure to
4968 * build with thread support to get basic thread safety.
4970 attribute_deprecated
4971 int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
4975 * Get the type of the given codec.
4977 enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
4980 * Get the name of a codec.
4981 * @return a static string identifying the codec; never NULL
4983 const char *avcodec_get_name(enum AVCodecID id);
4986 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
4987 * with no corresponding avcodec_close()), 0 otherwise.
4989 int avcodec_is_open(AVCodecContext *s);
4992 * @return a non-zero number if codec is an encoder, zero otherwise
4994 int av_codec_is_encoder(const AVCodec *codec);
4997 * @return a non-zero number if codec is a decoder, zero otherwise
4999 int av_codec_is_decoder(const AVCodec *codec);
5002 * Allocate a CPB properties structure and initialize its fields to default
5005 * @param size if non-NULL, the size of the allocated struct will be written
5006 * here. This is useful for embedding it in side data.
5008 * @return the newly allocated struct or NULL on failure
5010 AVCPBProperties *av_cpb_properties_alloc(size_t *size);
5016 #endif /* AVCODEC_AVCODEC_H */