har0ke/FFmpeg
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
FFmpeg/libavcodec/avcodec.h
Michael Niedermayer 8657eb9c3f
avcodec/avcodec: Warn about data returned from get_buffer*() 
Text based on suggestion by: epirat07@gmail.com
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
2024-08-18 23:04:28 +02:00

3093 lines
110 KiB
C
Raw Blame History

/*
* copyright (c) 2001 Fabrice Bellard
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVCODEC_AVCODEC_H
#define AVCODEC_AVCODEC_H
/**
* @file
* @ingroup libavc
* Libavcodec external API header
*/
#include "libavutil/samplefmt.h"
#include "libavutil/attributes.h"
#include "libavutil/avutil.h"
#include "libavutil/buffer.h"
#include "libavutil/channel_layout.h"
#include "libavutil/dict.h"
#include "libavutil/frame.h"
#include "libavutil/log.h"
#include "libavutil/pixfmt.h"
#include "libavutil/rational.h"
#include "codec.h"
#include "codec_id.h"
#include "defs.h"
#include "packet.h"
#include "version_major.h"
#ifndef HAVE_AV_CONFIG_H
/* When included as part of the ffmpeg build, only include the major version
* to avoid unnecessary rebuilds. When included externally, keep including
* the full version information. */
#include "version.h"
#include "codec_desc.h"
#include "codec_par.h"
#endif
struct AVCodecParameters;
/**
* @defgroup libavc libavcodec
* Encoding/Decoding Library
*
* @{
*
* @defgroup lavc_decoding Decoding
* @{
* @}
*
* @defgroup lavc_encoding Encoding
* @{
* @}
*
* @defgroup lavc_codec Codecs
* @{
* @defgroup lavc_codec_native Native Codecs
* @{
* @}
* @defgroup lavc_codec_wrappers External library wrappers
* @{
* @}
* @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
* @{
* @}
* @}
* @defgroup lavc_internal Internal
* @{
* @}
* @}
*/
/**
* @ingroup libavc
* @defgroup lavc_encdec send/receive encoding and decoding API overview
* @{
*
* The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
* avcodec_receive_packet() functions provide an encode/decode API, which
* decouples input and output.
*
* The API is very similar for encoding/decoding and audio/video, and works as
* follows:
* - Set up and open the AVCodecContext as usual.
* - Send valid input:
* - For decoding, call avcodec_send_packet() to give the decoder raw
* compressed data in an AVPacket.
* - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
* containing uncompressed audio or video.
*
* In both cases, it is recommended that AVPackets and AVFrames are
* refcounted, or libavcodec might have to copy the input data. (libavformat
* always returns refcounted AVPackets, and av_frame_get_buffer() allocates
* refcounted AVFrames.)
* - Receive output in a loop. Periodically call one of the avcodec_receive_*()
* functions and process their output:
* - For decoding, call avcodec_receive_frame(). On success, it will return
* an AVFrame containing uncompressed audio or video data.
* - For encoding, call avcodec_receive_packet(). On success, it will return
* an AVPacket with a compressed frame.
*
* Repeat this call until it returns AVERROR(EAGAIN) or an error. The
* AVERROR(EAGAIN) return value means that new input data is required to
* return new output. In this case, continue with sending input. For each
* input frame/packet, the codec will typically return 1 output frame/packet,
* but it can also be 0 or more than 1.
*
* At the beginning of decoding or encoding, the codec might accept multiple
* input frames/packets without returning a frame, until its internal buffers
* are filled. This situation is handled transparently if you follow the steps
* outlined above.
*
* In theory, sending input can result in EAGAIN - this should happen only if
* not all output was received. You can use this to structure alternative decode
* or encode loops other than the one suggested above. For example, you could
* try sending new input on each iteration, and try to receive output if that
* returns EAGAIN.
*
* End of stream situations. These require "flushing" (aka draining) the codec,
* as the codec might buffer multiple frames or packets internally for
* performance or out of necessity (consider B-frames).
* This is handled as follows:
* - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
* or avcodec_send_frame() (encoding) functions. This will enter draining
* mode.
* - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
* (encoding) in a loop until AVERROR_EOF is returned. The functions will
* not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
* - Before decoding can be resumed again, the codec has to be reset with
* avcodec_flush_buffers().
*
* Using the API as outlined above is highly recommended. But it is also
* possible to call functions outside of this rigid schema. For example, you can
* call avcodec_send_packet() repeatedly without calling
* avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
* until the codec's internal buffer has been filled up (which is typically of
* size 1 per output frame, after initial input), and then reject input with
* AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
* read at least some output.
*
* Not all codecs will follow a rigid and predictable dataflow; the only
* guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
* one end implies that a receive/send call on the other end will succeed, or
* at least will not fail with AVERROR(EAGAIN). In general, no codec will
* permit unlimited buffering of input or output.
*
* A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
* would be an invalid state, which could put the codec user into an endless
* loop. The API has no concept of time either: it cannot happen that trying to
* do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
* later accepts the packet (with no other receive/flush API calls involved).
* The API is a strict state machine, and the passage of time is not supposed
* to influence it. Some timing-dependent behavior might still be deemed
* acceptable in certain cases. But it must never result in both send/receive
* returning EAGAIN at the same time at any point. It must also absolutely be
* avoided that the current state is "unstable" and can "flip-flop" between
* the send/receive APIs allowing progress. For example, it's not allowed that
* the codec randomly decides that it actually wants to consume a packet now
* instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
* avcodec_send_packet() call.
* @}
*/
/**
* @defgroup lavc_core Core functions/structures.
* @ingroup libavc
*
* Basic definitions, functions for querying libavcodec capabilities,
* allocating core structures, etc.
* @{
*/
#if FF_API_BUFFER_MIN_SIZE
/**
* @ingroup lavc_encoding
* minimum encoding buffer size
* Used to avoid some checks during header writing.
* @deprecated Unused: avcodec_receive_packet() does not work
* with preallocated packet buffers.
*/
#define AV_INPUT_BUFFER_MIN_SIZE 16384
#endif
/**
* @ingroup lavc_encoding
*/
typedef struct RcOverride{
int start_frame;
int end_frame;
int qscale; // If this is 0 then quality_factor will be used instead.
float quality_factor;
} RcOverride;
/* encoding support
These flags can be passed in AVCodecContext.flags before initialization.
Note: Not everything is supported yet.
*/
/**
* Allow decoders to produce frames with data planes that are not aligned
* to CPU requirements (e.g. due to cropping).
*/
#define AV_CODEC_FLAG_UNALIGNED (1 << 0)
/**
* Use fixed qscale.
*/
#define AV_CODEC_FLAG_QSCALE (1 << 1)
/**
* 4 MV per MB allowed / advanced prediction for H.263.
*/
#define AV_CODEC_FLAG_4MV (1 << 2)
/**
* Output even those frames that might be corrupted.
*/
#define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
/**
* Use qpel MC.
*/
#define AV_CODEC_FLAG_QPEL (1 << 4)
#if FF_API_DROPCHANGED
/**
* Don't output frames whose parameters differ from first
* decoded frame in stream.
*
* @deprecated callers should implement this functionality in their own code
*/
#define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
#endif
/**
* Request the encoder to output reconstructed frames, i.e.\ frames that would
* be produced by decoding the encoded bistream. These frames may be retrieved
* by calling avcodec_receive_frame() immediately after a successful call to
* avcodec_receive_packet().
*
* Should only be used with encoders flagged with the
* @ref AV_CODEC_CAP_ENCODER_RECON_FRAME capability.
*
* @note
* Each reconstructed frame returned by the encoder corresponds to the last
* encoded packet, i.e. the frames are returned in coded order rather than
* presentation order.
*
* @note
* Frame parameters (like pixel format or dimensions) do not have to match the
* AVCodecContext values. Make sure to use the values from the returned frame.
*/
#define AV_CODEC_FLAG_RECON_FRAME (1 << 6)
/**
* @par decoding
* Request the decoder to propagate each packet's AVPacket.opaque and
* AVPacket.opaque_ref to its corresponding output AVFrame.
*
* @par encoding:
* Request the encoder to propagate each frame's AVFrame.opaque and
* AVFrame.opaque_ref values to its corresponding output AVPacket.
*
* @par
* May only be set on encoders that have the
* @ref AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability flag.
*
* @note
* While in typical cases one input frame produces exactly one output packet
* (perhaps after a delay), in general the mapping of frames to packets is
* M-to-N, so
* - Any number of input frames may be associated with any given output packet.
* This includes zero - e.g. some encoders may output packets that carry only
* metadata about the whole stream.
* - A given input frame may be associated with any number of output packets.
* Again this includes zero - e.g. some encoders may drop frames under certain
* conditions.
* .
* This implies that when using this flag, the caller must NOT assume that
* - a given input frame's opaques will necessarily appear on some output packet;
* - every output packet will have some non-NULL opaque value.
* .
* When an output packet contains multiple frames, the opaque values will be
* taken from the first of those.
*
* @note
* The converse holds for decoders, with frames and packets switched.
*/
#define AV_CODEC_FLAG_COPY_OPAQUE (1 << 7)
/**
* Signal to the encoder that the values of AVFrame.duration are valid and
* should be used (typically for transferring them to output packets).
*
* If this flag is not set, frame durations are ignored.
*/
#define AV_CODEC_FLAG_FRAME_DURATION (1 << 8)
/**
* Use internal 2pass ratecontrol in first pass mode.
*/
#define AV_CODEC_FLAG_PASS1 (1 << 9)
/**
* Use internal 2pass ratecontrol in second pass mode.
*/
#define AV_CODEC_FLAG_PASS2 (1 << 10)
/**
* loop filter.
*/
#define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
/**
* Only decode/encode grayscale.
*/
#define AV_CODEC_FLAG_GRAY (1 << 13)
/**
* error[?] variables will be set during encoding.
*/
#define AV_CODEC_FLAG_PSNR (1 << 15)
/**
* Use interlaced DCT.
*/
#define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
/**
* Force low delay.
*/
#define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
/**
* Place global headers in extradata instead of every keyframe.
*/
#define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
/**
* Use only bitexact stuff (except (I)DCT).
*/
#define AV_CODEC_FLAG_BITEXACT (1 << 23)
/* Fx : Flag for H.263+ extra options */
/**
* H.263 advanced intra coding / MPEG-4 AC prediction
*/
#define AV_CODEC_FLAG_AC_PRED (1 << 24)
/**
* interlaced motion estimation
*/
#define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
#define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
/**
* Allow non spec compliant speedup tricks.
*/
#define AV_CODEC_FLAG2_FAST (1 << 0)
/**
* Skip bitstream encoding.
*/
#define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
/**
* Place global headers at every keyframe instead of in extradata.
*/
#define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
/**
* Input bitstream might be truncated at a packet boundaries
* instead of only at frame boundaries.
*/
#define AV_CODEC_FLAG2_CHUNKS (1 << 15)
/**
* Discard cropping information from SPS.
*/
#define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
/**
* Show all frames before the first keyframe
*/
#define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
/**
* Export motion vectors through frame side data
*/
#define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
/**
* Do not skip samples and export skip information as frame side data
*/
#define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
/**
* Do not reset ASS ReadOrder field on flush (subtitles decoding)
*/
#define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
/**
* Generate/parse ICC profiles on encode/decode, as appropriate for the type of
* file. No effect on codecs which cannot contain embedded ICC profiles, or
* when compiled without support for lcms2.
*/
#define AV_CODEC_FLAG2_ICC_PROFILES (1U << 31)
/* Exported side data.
These flags can be passed in AVCodecContext.export_side_data before initialization.
*/
/**
* Export motion vectors through frame side data
*/
#define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
/**
* Export encoder Producer Reference Time through packet side data
*/
#define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
/**
* Decoding only.
* Export the AVVideoEncParams structure through frame side data.
*/
#define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
/**
* Decoding only.
* Do not apply film grain, export it instead.
*/
#define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
/**
* The decoder will keep a reference to the frame and may reuse it later.
*/
#define AV_GET_BUFFER_FLAG_REF (1 << 0)
/**
* The encoder will keep a reference to the packet and may reuse it later.
*/
#define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
/**
* main external API structure.
* New fields can be added to the end with minor version bumps.
* Removal, reordering and changes to existing fields require a major
* version bump.
* You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
* applications.
* The name string for AVOptions options matches the associated command line
* parameter name and can be found in libavcodec/options_table.h
* The AVOption/command line parameter names differ in some cases from the C
* structure field names for historic reasons or brevity.
* sizeof(AVCodecContext) must not be used outside libav*.
*/
typedef struct AVCodecContext {
/**
* information on struct for av_log
* - set by avcodec_alloc_context3
*/
const AVClass *av_class;
int log_level_offset;
enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
const struct AVCodec *codec;
enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
/**
* fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
* This is used to work around some encoder bugs.
* A demuxer should set this to what is stored in the field used to identify the codec.
* If there are multiple such fields in a container then the demuxer should choose the one
* which maximizes the information about the used codec.
* If the codec tag field in a container is larger than 32 bits then the demuxer should
* remap the longer ID to 32 bits with a table or other structure. Alternatively a new
* extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
* first.
* - encoding: Set by user, if not then the default based on codec_id will be used.
* - decoding: Set by user, will be converted to uppercase by libavcodec during init.
*/
unsigned int codec_tag;
void *priv_data;
/**
* Private context used for internal data.
*
* Unlike priv_data, this is not codec-specific. It is used in general
* libavcodec functions.
*/
struct AVCodecInternal *internal;
/**
* Private data of the user, can be used to carry app specific stuff.
* - encoding: Set by user.
* - decoding: Set by user.
*/
void *opaque;
/**
* the average bitrate
* - encoding: Set by user; unused for constant quantizer encoding.
* - decoding: Set by user, may be overwritten by libavcodec
* if this info is available in the stream
*/
int64_t bit_rate;
/**
* AV_CODEC_FLAG_*.
* - encoding: Set by user.
* - decoding: Set by user.
*/
int flags;
/**
* AV_CODEC_FLAG2_*
* - encoding: Set by user.
* - decoding: Set by user.
*/
int flags2;
/**
* some codecs need / can use extradata like Huffman tables.
* MJPEG: Huffman tables
* rv10: additional flags
* MPEG-4: global headers (they can be in the bitstream or here)
* The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
* than extradata_size to avoid problems if it is read with the bitstream reader.
* The bytewise contents of extradata must not depend on the architecture or CPU endianness.
* Must be allocated with the av_malloc() family of functions.
* - encoding: Set/allocated/freed by libavcodec.
* - decoding: Set/allocated/freed by user.
*/
uint8_t *extradata;
int extradata_size;
/**
* This is the fundamental unit of time (in seconds) in terms
* of which frame timestamps are represented. For fixed-fps content,
* timebase should be 1/framerate and timestamp increments should be
* identically 1.
* This often, but not always is the inverse of the frame rate or field rate
* for video. 1/time_base is not the average frame rate if the frame rate is not
* constant.
*
* Like containers, elementary streams also can store timestamps, 1/time_base
* is the unit in which these timestamps are specified.
* As example of such codec time base see ISO/IEC 14496-2:2001(E)
* vop_time_increment_resolution and fixed_vop_rate
* (fixed_vop_rate == 0 implies that it is different from the framerate)
*
* - encoding: MUST be set by user.
* - decoding: unused.
*/
AVRational time_base;
/**
* Timebase in which pkt_dts/pts and AVPacket.dts/pts are expressed.
* - encoding: unused.
* - decoding: set by user.
*/
AVRational pkt_timebase;
/**
* - decoding: For codecs that store a framerate value in the compressed
* bitstream, the decoder may export it here. { 0, 1} when
* unknown.
* - encoding: May be used to signal the framerate of CFR content to an
* encoder.
*/
AVRational framerate;
#if FF_API_TICKS_PER_FRAME
/**
* For some codecs, the time base is closer to the field rate than the frame rate.
* Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
* if no telecine is used ...
*
* Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
*
* @deprecated
* - decoding: Use AVCodecDescriptor.props & AV_CODEC_PROP_FIELDS
* - encoding: Set AVCodecContext.framerate instead
*
*/
attribute_deprecated
int ticks_per_frame;
#endif
/**
* Codec delay.
*
* Encoding: Number of frames delay there will be from the encoder input to
* the decoder output. (we assume the decoder matches the spec)
* Decoding: Number of frames delay in addition to what a standard decoder
* as specified in the spec would produce.
*
* Video:
* Number of frames the decoded output will be delayed relative to the
* encoded input.
*
* Audio:
* For encoding, this field is unused (see initial_padding).
*
* For decoding, this is the number of samples the decoder needs to
* output before the decoder's output is valid. When seeking, you should
* start decoding this many samples prior to your desired seek point.
*
* - encoding: Set by libavcodec.
* - decoding: Set by libavcodec.
*/
int delay;
/* video only */
/**
* picture width / height.
*
* @note Those fields may not match the values of the last
* AVFrame output by avcodec_receive_frame() due frame
* reordering.
*
* - encoding: MUST be set by user.
* - decoding: May be set by the user before opening the decoder if known e.g.
* from the container. Some decoders will require the dimensions
* to be set by the caller. During decoding, the decoder may
* overwrite those values as required while parsing the data.
*/
int width, height;
/**
* Bitstream width / height, may be different from width/height e.g. when
* the decoded frame is cropped before being output or lowres is enabled.
*
* @note Those field may not match the value of the last
* AVFrame output by avcodec_receive_frame() due frame
* reordering.
*
* - encoding: unused
* - decoding: May be set by the user before opening the decoder if known
* e.g. from the container. During decoding, the decoder may
* overwrite those values as required while parsing the data.
*/
int coded_width, coded_height;
/**
* sample aspect ratio (0 if unknown)
* That is the width of a pixel divided by the height of the pixel.
* Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
* - encoding: Set by user.
* - decoding: Set by libavcodec.
*/
AVRational sample_aspect_ratio;
/**
* Pixel format, see AV_PIX_FMT_xxx.
* May be set by the demuxer if known from headers.
* May be overridden by the decoder if it knows better.
*
* @note This field may not match the value of the last
* AVFrame output by avcodec_receive_frame() due frame
* reordering.
*
* - encoding: Set by user.
* - decoding: Set by user if known, overridden by libavcodec while
* parsing the data.
*/
enum AVPixelFormat pix_fmt;
/**
* Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
* - encoding: unused.
* - decoding: Set by libavcodec before calling get_format()
*/
enum AVPixelFormat sw_pix_fmt;
/**
* Chromaticity coordinates of the source primaries.
* - encoding: Set by user
* - decoding: Set by libavcodec
*/
enum AVColorPrimaries color_primaries;
/**
* Color Transfer Characteristic.
* - encoding: Set by user
* - decoding: Set by libavcodec
*/
enum AVColorTransferCharacteristic color_trc;
/**
* YUV colorspace type.
* - encoding: Set by user
* - decoding: Set by libavcodec
*/
enum AVColorSpace colorspace;
/**
* MPEG vs JPEG YUV range.
* - encoding: Set by user to override the default output color range value,
* If not specified, libavcodec sets the color range depending on the
* output format.
* - decoding: Set by libavcodec, can be set by the user to propagate the
* color range to components reading from the decoder context.
*/
enum AVColorRange color_range;
/**
* This defines the location of chroma samples.
* - encoding: Set by user
* - decoding: Set by libavcodec
*/
enum AVChromaLocation chroma_sample_location;
/** Field order
* - encoding: set by libavcodec
* - decoding: Set by user.
*/
enum AVFieldOrder field_order;
/**
* number of reference frames
* - encoding: Set by user.
* - decoding: Set by lavc.
*/
int refs;
/**
* Size of the frame reordering buffer in the decoder.
* For MPEG-2 it is 1 IPB or 0 low delay IP.
* - encoding: Set by libavcodec.
* - decoding: Set by libavcodec.
*/
int has_b_frames;
/**
* slice flags
* - encoding: unused
* - decoding: Set by user.
*/
int slice_flags;
#define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
#define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
#define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
/**
* If non NULL, 'draw_horiz_band' is called by the libavcodec
* decoder to draw a horizontal band. It improves cache usage. Not
* all codecs can do that. You must check the codec capabilities
* beforehand.
* When multithreading is used, it may be called from multiple threads
* at the same time; threads might draw different parts of the same AVFrame,
* or multiple AVFrames, and there is no guarantee that slices will be drawn
* in order.
* The function is also used by hardware acceleration APIs.
* It is called at least once during frame decoding to pass
* the data needed for hardware render.
* In that mode instead of pixel data, AVFrame points to
* a structure specific to the acceleration API. The application
* reads the structure and can change some fields to indicate progress
* or mark state.
* - encoding: unused
* - decoding: Set by user.
* @param height the height of the slice
* @param y the y position of the slice
* @param type 1->top field, 2->bottom field, 3->frame
* @param offset offset into the AVFrame.data from which the slice should be read
*/
void (*draw_horiz_band)(struct AVCodecContext *s,
const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
int y, int type, int height);
/**
* Callback to negotiate the pixel format. Decoding only, may be set by the
* caller before avcodec_open2().
*
* Called by some decoders to select the pixel format that will be used for
* the output frames. This is mainly used to set up hardware acceleration,
* then the provided format list contains the corresponding hwaccel pixel
* formats alongside the "software" one. The software pixel format may also
* be retrieved from \ref sw_pix_fmt.
*
* This callback will be called when the coded frame properties (such as
* resolution, pixel format, etc.) change and more than one output format is
* supported for those new properties. If a hardware pixel format is chosen
* and initialization for it fails, the callback may be called again
* immediately.
*
* This callback may be called from different threads if the decoder is
* multi-threaded, but not from more than one thread simultaneously.
*
* @param fmt list of formats which may be used in the current
* configuration, terminated by AV_PIX_FMT_NONE.
* @warning Behavior is undefined if the callback returns a value other
* than one of the formats in fmt or AV_PIX_FMT_NONE.
* @return the chosen format or AV_PIX_FMT_NONE
*/
enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
/**
* maximum number of B-frames between non-B-frames
* Note: The output will be delayed by max_b_frames+1 relative to the input.
* - encoding: Set by user.
* - decoding: unused
*/
int max_b_frames;
/**
* qscale factor between IP and B-frames
* If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
* If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
* - encoding: Set by user.
* - decoding: unused
*/
float b_quant_factor;
/**
* qscale offset between IP and B-frames
* - encoding: Set by user.
* - decoding: unused
*/
float b_quant_offset;
/**
* qscale factor between P- and I-frames
* If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
* If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
* - encoding: Set by user.
* - decoding: unused
*/
float i_quant_factor;
/**
* qscale offset between P and I-frames
* - encoding: Set by user.
* - decoding: unused
*/
float i_quant_offset;
/**
* luminance masking (0-> disabled)
* - encoding: Set by user.
* - decoding: unused
*/
float lumi_masking;
/**
* temporary complexity masking (0-> disabled)
* - encoding: Set by user.
* - decoding: unused
*/
float temporal_cplx_masking;
/**
* spatial complexity masking (0-> disabled)
* - encoding: Set by user.
* - decoding: unused
*/
float spatial_cplx_masking;
/**
* p block masking (0-> disabled)
* - encoding: Set by user.
* - decoding: unused
*/
float p_masking;
/**
* darkness masking (0-> disabled)
* - encoding: Set by user.
* - decoding: unused
*/
float dark_masking;
/**
* noise vs. sse weight for the nsse comparison function
* - encoding: Set by user.
* - decoding: unused
*/
int nsse_weight;
/**
* motion estimation comparison function
* - encoding: Set by user.
* - decoding: unused
*/
int me_cmp;
/**
* subpixel motion estimation comparison function
* - encoding: Set by user.
* - decoding: unused
*/
int me_sub_cmp;
/**
* macroblock comparison function (not supported yet)
* - encoding: Set by user.
* - decoding: unused
*/
int mb_cmp;
/**
* interlaced DCT comparison function
* - encoding: Set by user.
* - decoding: unused
*/
int ildct_cmp;
#define FF_CMP_SAD 0
#define FF_CMP_SSE 1
#define FF_CMP_SATD 2
#define FF_CMP_DCT 3
#define FF_CMP_PSNR 4
#define FF_CMP_BIT 5
#define FF_CMP_RD 6
#define FF_CMP_ZERO 7
#define FF_CMP_VSAD 8
#define FF_CMP_VSSE 9
#define FF_CMP_NSSE 10
#define FF_CMP_W53 11
#define FF_CMP_W97 12
#define FF_CMP_DCTMAX 13
#define FF_CMP_DCT264 14
#define FF_CMP_MEDIAN_SAD 15
#define FF_CMP_CHROMA 256
/**
* ME diamond size & shape
* - encoding: Set by user.
* - decoding: unused
*/
int dia_size;
/**
* amount of previous MV predictors (2a+1 x 2a+1 square)
* - encoding: Set by user.
* - decoding: unused
*/
int last_predictor_count;
/**
* motion estimation prepass comparison function
* - encoding: Set by user.
* - decoding: unused
*/
int me_pre_cmp;
/**
* ME prepass diamond size & shape
* - encoding: Set by user.
* - decoding: unused
*/
int pre_dia_size;
/**
* subpel ME quality
* - encoding: Set by user.
* - decoding: unused
*/
int me_subpel_quality;
/**
* maximum motion estimation search range in subpel units
* If 0 then no limit.
*
* - encoding: Set by user.
* - decoding: unused
*/
int me_range;
/**
* macroblock decision mode
* - encoding: Set by user.
* - decoding: unused
*/
int mb_decision;
#define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
#define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
#define FF_MB_DECISION_RD 2 ///< rate distortion
/**
* custom intra quantization matrix
* Must be allocated with the av_malloc() family of functions, and will be freed in
* avcodec_free_context().
* - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
* - decoding: Set/allocated/freed by libavcodec.
*/
uint16_t *intra_matrix;
/**
* custom inter quantization matrix
* Must be allocated with the av_malloc() family of functions, and will be freed in
* avcodec_free_context().
* - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
* - decoding: Set/allocated/freed by libavcodec.
*/
uint16_t *inter_matrix;
/**
* custom intra quantization matrix
* - encoding: Set by user, can be NULL.
* - decoding: unused.
*/
uint16_t *chroma_intra_matrix;
/**
* precision of the intra DC coefficient - 8
* - encoding: Set by user.
* - decoding: Set by libavcodec
*/
int intra_dc_precision;
/**
* minimum MB Lagrange multiplier
* - encoding: Set by user.
* - decoding: unused
*/
int mb_lmin;
/**
* maximum MB Lagrange multiplier
* - encoding: Set by user.
* - decoding: unused
*/
int mb_lmax;
/**
* - encoding: Set by user.
* - decoding: unused
*/
int bidir_refine;
/**
* minimum GOP size
* - encoding: Set by user.
* - decoding: unused
*/
int keyint_min;
/**
* the number of pictures in a group of pictures, or 0 for intra_only
* - encoding: Set by user.
* - decoding: unused
*/
int gop_size;
/**
* Note: Value depends upon the compare function used for fullpel ME.
* - encoding: Set by user.
* - decoding: unused
*/
int mv0_threshold;
/**
* Number of slices.
* Indicates number of picture subdivisions. Used for parallelized
* decoding.
* - encoding: Set by user
* - decoding: unused
*/
int slices;
/* audio only */
int sample_rate; ///< samples per second
/**
* audio sample format
* - encoding: Set by user.
* - decoding: Set by libavcodec.
*/
enum AVSampleFormat sample_fmt; ///< sample format
/**
* Audio channel layout.
* - encoding: must be set by the caller, to one of AVCodec.ch_layouts.
* - decoding: may be set by the caller if known e.g. from the container.
* The decoder can then override during decoding as needed.
*/
AVChannelLayout ch_layout;
/* The following data should not be initialized. */
/**
* Number of samples per channel in an audio frame.
*
* - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
* except the last must contain exactly frame_size samples per channel.
* May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
* frame size is not restricted.
* - decoding: may be set by some decoders to indicate constant frame size
*/
int frame_size;
/**
* number of bytes per packet if constant and known or 0
* Used by some WAV based audio codecs.
*/
int block_align;
/**
* Audio cutoff bandwidth (0 means "automatic")
* - encoding: Set by user.
* - decoding: unused
*/
int cutoff;
/**
* Type of service that the audio stream conveys.
* - encoding: Set by user.
* - decoding: Set by libavcodec.
*/
enum AVAudioServiceType audio_service_type;
/**
* desired sample format
* - encoding: Not used.
* - decoding: Set by user.
* Decoder will decode to this format if it can.
*/
enum AVSampleFormat request_sample_fmt;
/**
* Audio only. The number of "priming" samples (padding) inserted by the
* encoder at the beginning of the audio. I.e. this number of leading
* decoded samples must be discarded by the caller to get the original audio
* without leading padding.
*
* - decoding: unused
* - encoding: Set by libavcodec. The timestamps on the output packets are
* adjusted by the encoder so that they always refer to the
* first sample of the data actually contained in the packet,
* including any added padding. E.g. if the timebase is
* 1/samplerate and the timestamp of the first input sample is
* 0, the timestamp of the first output packet will be
* -initial_padding.
*/
int initial_padding;
/**
* Audio only. The amount of padding (in samples) appended by the encoder to
* the end of the audio. I.e. this number of decoded samples must be
* discarded by the caller from the end of the stream to get the original
* audio without any trailing padding.
*
* - decoding: unused
* - encoding: unused
*/
int trailing_padding;
/**
* Number of samples to skip after a discontinuity
* - decoding: unused
* - encoding: set by libavcodec
*/
int seek_preroll;
/**
* This callback is called at the beginning of each frame to get data
* buffer(s) for it. There may be one contiguous buffer for all the data or
* there may be a buffer per each data plane or anything in between. What
* this means is, you may set however many entries in buf[] you feel necessary.
* Each buffer must be reference-counted using the AVBuffer API (see description
* of buf[] below).
*
* The following fields will be set in the frame before this callback is
* called:
* - format
* - width, height (video only)
* - sample_rate, channel_layout, nb_samples (audio only)
* Their values may differ from the corresponding values in
* AVCodecContext. This callback must use the frame values, not the codec
* context values, to calculate the required buffer size.
*
* This callback must fill the following fields in the frame:
* - data[]
* - linesize[]
* - extended_data:
* * if the data is planar audio with more than 8 channels, then this
* callback must allocate and fill extended_data to contain all pointers
* to all data planes. data[] must hold as many pointers as it can.
* extended_data must be allocated with av_malloc() and will be freed in
* av_frame_unref().
* * otherwise extended_data must point to data
* - buf[] must contain one or more pointers to AVBufferRef structures. Each of
* the frame's data and extended_data pointers must be contained in these. That
* is, one AVBufferRef for each allocated chunk of memory, not necessarily one
* AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
* and av_buffer_ref().
* - extended_buf and nb_extended_buf must be allocated with av_malloc() by
* this callback and filled with the extra buffers if there are more
* buffers than buf[] can hold. extended_buf will be freed in
* av_frame_unref().
* Decoders will generally initialize the whole buffer before it is output
* but it can in rare error conditions happen that uninitialized data is passed
* through. \important The buffers returned by get_buffer* should thus not contain sensitive
* data.
*
* If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
* avcodec_default_get_buffer2() instead of providing buffers allocated by
* some other means.
*
* Each data plane must be aligned to the maximum required by the target
* CPU.
*
* @see avcodec_default_get_buffer2()
*
* Video:
*
* If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
* (read and/or written to if it is writable) later by libavcodec.
*
* avcodec_align_dimensions2() should be used to find the required width and
* height, as they normally need to be rounded up to the next multiple of 16.
*
* Some decoders do not support linesizes changing between frames.
*
* If frame multithreading is used, this callback may be called from a
* different thread, but not from more than one at once. Does not need to be
* reentrant.
*
* @see avcodec_align_dimensions2()
*
* Audio:
*
* Decoders request a buffer of a particular size by setting
* AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
* however, utilize only part of the buffer by setting AVFrame.nb_samples
* to a smaller value in the output frame.
*
* As a convenience, av_samples_get_buffer_size() and
* av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
* functions to find the required data size and to fill data pointers and
* linesize. In AVFrame.linesize, only linesize[0] may be set for audio
* since all planes must be the same size.
*
* @see av_samples_get_buffer_size(), av_samples_fill_arrays()
*
* - encoding: unused
* - decoding: Set by libavcodec, user can override.
*/
int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
/* - encoding parameters */
/**
* number of bits the bitstream is allowed to diverge from the reference.
* the reference can be CBR (for CBR pass1) or VBR (for pass2)
* - encoding: Set by user; unused for constant quantizer encoding.
* - decoding: unused
*/
int bit_rate_tolerance;
/**
* Global quality for codecs which cannot change it per frame.
* This should be proportional to MPEG-1/2/4 qscale.
* - encoding: Set by user.
* - decoding: unused
*/
int global_quality;
/**
* - encoding: Set by user.
* - decoding: unused
*/
int compression_level;
#define FF_COMPRESSION_DEFAULT -1
float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
/**
* minimum quantizer
* - encoding: Set by user.
* - decoding: unused
*/
int qmin;
/**
* maximum quantizer
* - encoding: Set by user.
* - decoding: unused
*/
int qmax;
/**
* maximum quantizer difference between frames
* - encoding: Set by user.
* - decoding: unused
*/
int max_qdiff;
/**
* decoder bitstream buffer size
* - encoding: Set by user.
* - decoding: May be set by libavcodec.
*/
int rc_buffer_size;
/**
* ratecontrol override, see RcOverride
* - encoding: Allocated/set/freed by user.
* - decoding: unused
*/
int rc_override_count;
RcOverride *rc_override;
/**
* maximum bitrate
* - encoding: Set by user.
* - decoding: Set by user, may be overwritten by libavcodec.
*/
int64_t rc_max_rate;
/**
* minimum bitrate
* - encoding: Set by user.
* - decoding: unused
*/
int64_t rc_min_rate;
/**
* Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
* - encoding: Set by user.
* - decoding: unused.
*/
float rc_max_available_vbv_use;
/**
* Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
* - encoding: Set by user.
* - decoding: unused.
*/
float rc_min_vbv_overflow_use;
/**
* Number of bits which should be loaded into the rc buffer before decoding starts.
* - encoding: Set by user.
* - decoding: unused
*/
int rc_initial_buffer_occupancy;
/**
* trellis RD quantization
* - encoding: Set by user.
* - decoding: unused
*/
int trellis;
/**
* pass1 encoding statistics output buffer
* - encoding: Set by libavcodec.
* - decoding: unused
*/
char *stats_out;
/**
* pass2 encoding statistics input buffer
* Concatenated stuff from stats_out of pass1 should be placed here.
* - encoding: Allocated/set/freed by user.
* - decoding: unused
*/
char *stats_in;
/**
* Work around bugs in encoders which sometimes cannot be detected automatically.
* - encoding: Set by user
* - decoding: Set by user
*/
int workaround_bugs;
#define FF_BUG_AUTODETECT 1 ///< autodetection
#define FF_BUG_XVID_ILACE 4
#define FF_BUG_UMP4 8
#define FF_BUG_NO_PADDING 16
#define FF_BUG_AMV 32
#define FF_BUG_QPEL_CHROMA 64
#define FF_BUG_STD_QPEL 128
#define FF_BUG_QPEL_CHROMA2 256
#define FF_BUG_DIRECT_BLOCKSIZE 512
#define FF_BUG_EDGE 1024
#define FF_BUG_HPEL_CHROMA 2048
#define FF_BUG_DC_CLIP 4096
#define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
#define FF_BUG_TRUNCATED 16384
#define FF_BUG_IEDGE 32768
/**
* strictly follow the standard (MPEG-4, ...).
* - encoding: Set by user.
* - decoding: Set by user.
* Setting this to STRICT or higher means the encoder and decoder will
* generally do stupid things, whereas setting it to unofficial or lower
* will mean the encoder might produce output that is not supported by all
* spec-compliant decoders. Decoders don't differentiate between normal,
* unofficial and experimental (that is, they always try to decode things
* when they can) unless they are explicitly asked to behave stupidly
* (=strictly conform to the specs)
* This may only be set to one of the FF_COMPLIANCE_* values in defs.h.
*/
int strict_std_compliance;
/**
* error concealment flags
* - encoding: unused
* - decoding: Set by user.
*/
int error_concealment;
#define FF_EC_GUESS_MVS 1
#define FF_EC_DEBLOCK 2
#define FF_EC_FAVOR_INTER 256
/**
* debug
* - encoding: Set by user.
* - decoding: Set by user.
*/
int debug;
#define FF_DEBUG_PICT_INFO 1
#define FF_DEBUG_RC 2
#define FF_DEBUG_BITSTREAM 4
#define FF_DEBUG_MB_TYPE 8
#define FF_DEBUG_QP 16
#define FF_DEBUG_DCT_COEFF 0x00000040
#define FF_DEBUG_SKIP 0x00000080
#define FF_DEBUG_STARTCODE 0x00000100
#define FF_DEBUG_ER 0x00000400
#define FF_DEBUG_MMCO 0x00000800
#define FF_DEBUG_BUGS 0x00001000
#define FF_DEBUG_BUFFERS 0x00008000
#define FF_DEBUG_THREADS 0x00010000
#define FF_DEBUG_GREEN_MD 0x00800000
#define FF_DEBUG_NOMC 0x01000000
/**
* Error recognition; may misdetect some more or less valid parts as errors.
* This is a bitfield of the AV_EF_* values defined in defs.h.
*
* - encoding: Set by user.
* - decoding: Set by user.
*/
int err_recognition;
/**
* Hardware accelerator in use
* - encoding: unused.
* - decoding: Set by libavcodec
*/
const struct AVHWAccel *hwaccel;
/**
* Legacy hardware accelerator context.
*
* For some hardware acceleration methods, the caller may use this field to
* signal hwaccel-specific data to the codec. The struct pointed to by this
* pointer is hwaccel-dependent and defined in the respective header. Please
* refer to the FFmpeg HW accelerator documentation to know how to fill
* this.
*
* In most cases this field is optional - the necessary information may also
* be provided to libavcodec through @ref hw_frames_ctx or @ref
* hw_device_ctx (see avcodec_get_hw_config()). However, in some cases it
* may be the only method of signalling some (optional) information.
*
* The struct and its contents are owned by the caller.
*
* - encoding: May be set by the caller before avcodec_open2(). Must remain
* valid until avcodec_free_context().
* - decoding: May be set by the caller in the get_format() callback.
* Must remain valid until the next get_format() call,
* or avcodec_free_context() (whichever comes first).
*/
void *hwaccel_context;
/**
* A reference to the AVHWFramesContext describing the input (for encoding)
* or output (decoding) frames. The reference is set by the caller and
* afterwards owned (and freed) by libavcodec - it should never be read by
* the caller after being set.
*
* - decoding: This field should be set by the caller from the get_format()
* callback. The previous reference (if any) will always be
* unreffed by libavcodec before the get_format() call.
*
* If the default get_buffer2() is used with a hwaccel pixel
* format, then this AVHWFramesContext will be used for
* allocating the frame buffers.
*
* - encoding: For hardware encoders configured to use a hwaccel pixel
* format, this field should be set by the caller to a reference
* to the AVHWFramesContext describing input frames.
* AVHWFramesContext.format must be equal to
* AVCodecContext.pix_fmt.
*
* This field should be set before avcodec_open2() is called.
*/
AVBufferRef *hw_frames_ctx;
/**
* A reference to the AVHWDeviceContext describing the device which will
* be used by a hardware encoder/decoder. The reference is set by the
* caller and afterwards owned (and freed) by libavcodec.
*
* This should be used if either the codec device does not require
* hardware frames or any that are used are to be allocated internally by
* libavcodec. If the user wishes to supply any of the frames used as
* encoder input or decoder output then hw_frames_ctx should be used
* instead. When hw_frames_ctx is set in get_format() for a decoder, this
* field will be ignored while decoding the associated stream segment, but
* may again be used on a following one after another get_format() call.
*
* For both encoders and decoders this field should be set before
* avcodec_open2() is called and must not be written to thereafter.
*
* Note that some decoders may require this field to be set initially in
* order to support hw_frames_ctx at all - in that case, all frames
* contexts used must be created on the same device.
*/
AVBufferRef *hw_device_ctx;
/**
* Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
* decoding (if active).
* - encoding: unused
* - decoding: Set by user (either before avcodec_open2(), or in the
* AVCodecContext.get_format callback)
*/
int hwaccel_flags;
/**
* Video decoding only. Sets the number of extra hardware frames which
* the decoder will allocate for use by the caller. This must be set
* before avcodec_open2() is called.
*
* Some hardware decoders require all frames that they will use for
* output to be defined in advance before decoding starts. For such
* decoders, the hardware frame pool must therefore be of a fixed size.
* The extra frames set here are on top of any number that the decoder
* needs internally in order to operate normally (for example, frames
* used as reference pictures).
*/
int extra_hw_frames;
/**
* error
* - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
* - decoding: unused
*/
uint64_t error[AV_NUM_DATA_POINTERS];
/**
* DCT algorithm, see FF_DCT_* below
* - encoding: Set by user.
* - decoding: unused
*/
int dct_algo;
#define FF_DCT_AUTO 0
#define FF_DCT_FASTINT 1
#define FF_DCT_INT 2
#define FF_DCT_MMX 3
#define FF_DCT_ALTIVEC 5
#define FF_DCT_FAAN 6
#define FF_DCT_NEON 7
/**
* IDCT algorithm, see FF_IDCT_* below.
* - encoding: Set by user.
* - decoding: Set by user.
*/
int idct_algo;
#define FF_IDCT_AUTO 0
#define FF_IDCT_INT 1
#define FF_IDCT_SIMPLE 2
#define FF_IDCT_SIMPLEMMX 3
#define FF_IDCT_ARM 7
#define FF_IDCT_ALTIVEC 8
#define FF_IDCT_SIMPLEARM 10
#define FF_IDCT_XVID 14
#define FF_IDCT_SIMPLEARMV5TE 16
#define FF_IDCT_SIMPLEARMV6 17
#define FF_IDCT_FAAN 20
#define FF_IDCT_SIMPLENEON 22
#define FF_IDCT_SIMPLEAUTO 128
/**
* bits per sample/pixel from the demuxer (needed for huffyuv).
* - encoding: Set by libavcodec.
* - decoding: Set by user.
*/
int bits_per_coded_sample;
/**
* Bits per sample/pixel of internal libavcodec pixel/sample format.
* - encoding: set by user.
* - decoding: set by libavcodec.
*/
int bits_per_raw_sample;
/**
* thread count
* is used to decide how many independent tasks should be passed to execute()
* - encoding: Set by user.
* - decoding: Set by user.
*/
int thread_count;
/**
* Which multithreading methods to use.
* Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
* so clients which cannot provide future frames should not use it.
*
* - encoding: Set by user, otherwise the default is used.
* - decoding: Set by user, otherwise the default is used.
*/
int thread_type;
#define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
#define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
/**
* Which multithreading methods are in use by the codec.
* - encoding: Set by libavcodec.
* - decoding: Set by libavcodec.
*/
int active_thread_type;
/**
* The codec may call this to execute several independent things.
* It will return only after finishing all tasks.
* The user may replace this with some multithreaded implementation,
* the default implementation will execute the parts serially.
* @param count the number of things to execute
* - encoding: Set by libavcodec, user can override.
* - decoding: Set by libavcodec, user can override.
*/
int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
/**
* The codec may call this to execute several independent things.
* It will return only after finishing all tasks.
* The user may replace this with some multithreaded implementation,
* the default implementation will execute the parts serially.
* @param c context passed also to func
* @param count the number of things to execute
* @param arg2 argument passed unchanged to func
* @param ret return values of executed functions, must have space for "count" values. May be NULL.
* @param func function that will be called count times, with jobnr from 0 to count-1.
* threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
* two instances of func executing at the same time will have the same threadnr.
* @return always 0 currently, but code should handle a future improvement where when any call to func
* returns < 0 no further calls to func may be done and < 0 is returned.
* - encoding: Set by libavcodec, user can override.
* - decoding: Set by libavcodec, user can override.
*/
int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
/**
* profile
* - encoding: Set by user.
* - decoding: Set by libavcodec.
* See the AV_PROFILE_* defines in defs.h.
*/
int profile;
#if FF_API_FF_PROFILE_LEVEL
/** @deprecated The following defines are deprecated; use AV_PROFILE_*
* in defs.h instead. */
#define FF_PROFILE_UNKNOWN -99
#define FF_PROFILE_RESERVED -100
#define FF_PROFILE_AAC_MAIN 0
#define FF_PROFILE_AAC_LOW 1
#define FF_PROFILE_AAC_SSR 2
#define FF_PROFILE_AAC_LTP 3
#define FF_PROFILE_AAC_HE 4
#define FF_PROFILE_AAC_HE_V2 28
#define FF_PROFILE_AAC_LD 22
#define FF_PROFILE_AAC_ELD 38
#define FF_PROFILE_MPEG2_AAC_LOW 128
#define FF_PROFILE_MPEG2_AAC_HE 131
#define FF_PROFILE_DNXHD 0
#define FF_PROFILE_DNXHR_LB 1
#define FF_PROFILE_DNXHR_SQ 2
#define FF_PROFILE_DNXHR_HQ 3
#define FF_PROFILE_DNXHR_HQX 4
#define FF_PROFILE_DNXHR_444 5
#define FF_PROFILE_DTS 20
#define FF_PROFILE_DTS_ES 30
#define FF_PROFILE_DTS_96_24 40
#define FF_PROFILE_DTS_HD_HRA 50
#define FF_PROFILE_DTS_HD_MA 60
#define FF_PROFILE_DTS_EXPRESS 70
#define FF_PROFILE_DTS_HD_MA_X 61
#define FF_PROFILE_DTS_HD_MA_X_IMAX 62
#define FF_PROFILE_EAC3_DDP_ATMOS 30
#define FF_PROFILE_TRUEHD_ATMOS 30
#define FF_PROFILE_MPEG2_422 0
#define FF_PROFILE_MPEG2_HIGH 1
#define FF_PROFILE_MPEG2_SS 2
#define FF_PROFILE_MPEG2_SNR_SCALABLE 3
#define FF_PROFILE_MPEG2_MAIN 4
#define FF_PROFILE_MPEG2_SIMPLE 5
#define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
#define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
#define FF_PROFILE_H264_BASELINE 66
#define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
#define FF_PROFILE_H264_MAIN 77
#define FF_PROFILE_H264_EXTENDED 88
#define FF_PROFILE_H264_HIGH 100
#define FF_PROFILE_H264_HIGH_10 110
#define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
#define FF_PROFILE_H264_MULTIVIEW_HIGH 118
#define FF_PROFILE_H264_HIGH_422 122
#define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
#define FF_PROFILE_H264_STEREO_HIGH 128
#define FF_PROFILE_H264_HIGH_444 144
#define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
#define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
#define FF_PROFILE_H264_CAVLC_444 44
#define FF_PROFILE_VC1_SIMPLE 0
#define FF_PROFILE_VC1_MAIN 1
#define FF_PROFILE_VC1_COMPLEX 2
#define FF_PROFILE_VC1_ADVANCED 3
#define FF_PROFILE_MPEG4_SIMPLE 0
#define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
#define FF_PROFILE_MPEG4_CORE 2
#define FF_PROFILE_MPEG4_MAIN 3
#define FF_PROFILE_MPEG4_N_BIT 4
#define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
#define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
#define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
#define FF_PROFILE_MPEG4_HYBRID 8
#define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
#define FF_PROFILE_MPEG4_CORE_SCALABLE 10
#define FF_PROFILE_MPEG4_ADVANCED_CODING 11
#define FF_PROFILE_MPEG4_ADVANCED_CORE 12
#define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
#define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
#define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
#define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
#define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
#define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
#define FF_PROFILE_JPEG2000_DCINEMA_2K 3
#define FF_PROFILE_JPEG2000_DCINEMA_4K 4
#define FF_PROFILE_VP9_0 0
#define FF_PROFILE_VP9_1 1
#define FF_PROFILE_VP9_2 2
#define FF_PROFILE_VP9_3 3
#define FF_PROFILE_HEVC_MAIN 1
#define FF_PROFILE_HEVC_MAIN_10 2
#define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
#define FF_PROFILE_HEVC_REXT 4
#define FF_PROFILE_HEVC_SCC 9
#define FF_PROFILE_VVC_MAIN_10 1
#define FF_PROFILE_VVC_MAIN_10_444 33
#define FF_PROFILE_AV1_MAIN 0
#define FF_PROFILE_AV1_HIGH 1
#define FF_PROFILE_AV1_PROFESSIONAL 2
#define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
#define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
#define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
#define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
#define FF_PROFILE_MJPEG_JPEG_LS 0xf7
#define FF_PROFILE_SBC_MSBC 1
#define FF_PROFILE_PRORES_PROXY 0
#define FF_PROFILE_PRORES_LT 1
#define FF_PROFILE_PRORES_STANDARD 2
#define FF_PROFILE_PRORES_HQ 3
#define FF_PROFILE_PRORES_4444 4
#define FF_PROFILE_PRORES_XQ 5
#define FF_PROFILE_ARIB_PROFILE_A 0
#define FF_PROFILE_ARIB_PROFILE_C 1
#define FF_PROFILE_KLVA_SYNC 0
#define FF_PROFILE_KLVA_ASYNC 1
#define FF_PROFILE_EVC_BASELINE 0
#define FF_PROFILE_EVC_MAIN 1
#endif
/**
* Encoding level descriptor.
* - encoding: Set by user, corresponds to a specific level defined by the
* codec, usually corresponding to the profile level, if not specified it
* is set to FF_LEVEL_UNKNOWN.
* - decoding: Set by libavcodec.
* See AV_LEVEL_* in defs.h.
*/
int level;
#if FF_API_FF_PROFILE_LEVEL
/** @deprecated The following define is deprecated; use AV_LEVEL_UNKOWN
* in defs.h instead. */
#define FF_LEVEL_UNKNOWN -99
#endif
/**
* Properties of the stream that gets decoded
* - encoding: unused
* - decoding: set by libavcodec
*/
unsigned properties;
#define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
#define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
#define FF_CODEC_PROPERTY_FILM_GRAIN 0x00000004
/**
* Skip loop filtering for selected frames.
* - encoding: unused
* - decoding: Set by user.
*/
enum AVDiscard skip_loop_filter;
/**
* Skip IDCT/dequantization for selected frames.
* - encoding: unused
* - decoding: Set by user.
*/
enum AVDiscard skip_idct;
/**
* Skip decoding for selected frames.
* - encoding: unused
* - decoding: Set by user.
*/
enum AVDiscard skip_frame;
/**
* Skip processing alpha if supported by codec.
* Note that if the format uses pre-multiplied alpha (common with VP6,
* and recommended due to better video quality/compression)
* the image will look as if alpha-blended onto a black background.
* However for formats that do not use pre-multiplied alpha
* there might be serious artefacts (though e.g. libswscale currently
* assumes pre-multiplied alpha anyway).
*
* - decoding: set by user
* - encoding: unused
*/
int skip_alpha;
/**
* Number of macroblock rows at the top which are skipped.
* - encoding: unused
* - decoding: Set by user.
*/
int skip_top;
/**
* Number of macroblock rows at the bottom which are skipped.
* - encoding: unused
* - decoding: Set by user.
*/
int skip_bottom;
/**
* low resolution decoding, 1-> 1/2 size, 2->1/4 size
* - encoding: unused
* - decoding: Set by user.
*/
int lowres;
/**
* AVCodecDescriptor
* - encoding: unused.
* - decoding: set by libavcodec.
*/
const struct AVCodecDescriptor *codec_descriptor;
/**
* Character encoding of the input subtitles file.
* - decoding: set by user
* - encoding: unused
*/
char *sub_charenc;
/**
* Subtitles character encoding mode. Formats or codecs might be adjusting
* this setting (if they are doing the conversion themselves for instance).
* - decoding: set by libavcodec
* - encoding: unused
*/
int sub_charenc_mode;
#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)
#define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
#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
#define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
/**
* Header containing style information for text subtitles.
* For SUBTITLE_ASS subtitle type, it should contain the whole ASS
* [Script Info] and [V4+ Styles] section, plus the [Events] line and
* the Format line following. It shouldn't include any Dialogue line.
* - encoding: Set/allocated/freed by user (before avcodec_open2())
* - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
*/
int subtitle_header_size;
uint8_t *subtitle_header;
/**
* dump format separator.
* can be ", " or "\n " or anything else
* - encoding: Set by user.
* - decoding: Set by user.
*/
uint8_t *dump_separator;
/**
* ',' separated list of allowed decoders.
* If NULL then all are allowed
* - encoding: unused
* - decoding: set by user
*/
char *codec_whitelist;
/**
* Additional data associated with the entire coded stream.
*
* - decoding: may be set by user before calling avcodec_open2().
* - encoding: may be set by libavcodec after avcodec_open2().
*/
AVPacketSideData *coded_side_data;
int nb_coded_side_data;
/**
* Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
* metadata exported in frame, packet, or coded stream side data by
* decoders and encoders.
*
* - decoding: set by user
* - encoding: set by user
*/
int export_side_data;
/**
* The number of pixels per image to maximally accept.
*
* - decoding: set by user
* - encoding: set by user
*/
int64_t max_pixels;
/**
* Video decoding only. Certain video codecs support cropping, meaning that
* only a sub-rectangle of the decoded frame is intended for display. This
* option controls how cropping is handled by libavcodec.
*
* When set to 1 (the default), libavcodec will apply cropping internally.
* I.e. it will modify the output frame width/height fields and offset the
* data pointers (only by as much as possible while preserving alignment, or
* by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
* the frames output by the decoder refer only to the cropped area. The
* crop_* fields of the output frames will be zero.
*
* When set to 0, the width/height fields of the output frames will be set
* to the coded dimensions and the crop_* fields will describe the cropping
* rectangle. Applying the cropping is left to the caller.
*
* @warning When hardware acceleration with opaque output frames is used,
* libavcodec is unable to apply cropping from the top/left border.
*
* @note when this option is set to zero, the width/height fields of the
* AVCodecContext and output AVFrames have different meanings. The codec
* context fields store display dimensions (with the coded dimensions in
* coded_width/height), while the frame fields store the coded dimensions
* (with the display dimensions being determined by the crop_* fields).
*/
int apply_cropping;
/**
* The percentage of damaged samples to discard a frame.
*
* - decoding: set by user
* - encoding: unused
*/
int discard_damaged_percentage;
/**
* The number of samples per frame to maximally accept.
*
* - decoding: set by user
* - encoding: set by user
*/
int64_t max_samples;
/**
* This callback is called at the beginning of each packet to get a data
* buffer for it.
*
* The following field will be set in the packet before this callback is
* called:
* - size
* This callback must use the above value to calculate the required buffer size,
* which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
*
* In some specific cases, the encoder may not use the entire buffer allocated by this
* callback. This will be reflected in the size value in the packet once returned by
* avcodec_receive_packet().
*
* This callback must fill the following fields in the packet:
* - data: alignment requirements for AVPacket apply, if any. Some architectures and
* encoders may benefit from having aligned data.
* - buf: must contain a pointer to an AVBufferRef structure. The packet's
* data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
* and av_buffer_ref().
*
* If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
* avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
* some other means.
*
* The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
* They may be used for example to hint what use the buffer may get after being
* created.
* Implementations of this callback may ignore flags they don't understand.
* If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
* (read and/or written to if it is writable) later by libavcodec.
*
* This callback must be thread-safe, as when frame threading is used, it may
* be called from multiple threads simultaneously.
*
* @see avcodec_default_get_encode_buffer()
*
* - encoding: Set by libavcodec, user can override.
* - decoding: unused
*/
int (*get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags);
/**
* Frame counter, set by libavcodec.
*
* - decoding: total number of frames returned from the decoder so far.
* - encoding: total number of frames passed to the encoder so far.
*
* @note the counter is not incremented if encoding/decoding resulted in
* an error.
*/
int64_t frame_num;
/**
* Decoding only. May be set by the caller before avcodec_open2() to an
* av_malloc()'ed array (or via AVOptions). Owned and freed by the decoder
* afterwards.
*
* Side data attached to decoded frames may come from several sources:
* 1. coded_side_data, which the decoder will for certain types translate
* from packet-type to frame-type and attach to frames;
* 2. side data attached to an AVPacket sent for decoding (same
* considerations as above);
* 3. extracted from the coded bytestream.
* The first two cases are supplied by the caller and typically come from a
* container.
*
* This array configures decoder behaviour in cases when side data of the
* same type is present both in the coded bytestream and in the
* user-supplied side data (items 1. and 2. above). In all cases, at most
* one instance of each side data type will be attached to output frames. By
* default it will be the bytestream side data. Adding an
* AVPacketSideDataType value to this array will flip the preference for
* this type, thus making the decoder prefer user-supplied side data over
* bytestream. In case side data of the same type is present both in
* coded_data and attacked to a packet, the packet instance always has
* priority.
*
* The array may also contain a single -1, in which case the preference is
* switched for all side data types.
*/
int *side_data_prefer_packet;
/**
* Number of entries in side_data_prefer_packet.
*/
unsigned nb_side_data_prefer_packet;
/**
* Array containing static side data, such as HDR10 CLL / MDCV structures.
* Side data entries should be allocated by usage of helpers defined in
* libavutil/frame.h.
*
* - encoding: may be set by user before calling avcodec_open2() for
* encoder configuration. Afterwards owned and freed by the
* encoder.
* - decoding: may be set by libavcodec in avcodec_open2().
*/
AVFrameSideData **decoded_side_data;
int nb_decoded_side_data;
} AVCodecContext;
/**
* @defgroup lavc_hwaccel AVHWAccel
*
* @note Nothing in this structure should be accessed by the user. At some
* point in future it will not be externally visible at all.
*
* @{
*/
typedef struct AVHWAccel {
/**
* Name of the hardware accelerated codec.
* The name is globally unique among encoders and among decoders (but an
* encoder and a decoder can share the same name).
*/
const char *name;
/**
* Type of codec implemented by the hardware accelerator.
*
* See AVMEDIA_TYPE_xxx
*/
enum AVMediaType type;
/**
* Codec implemented by the hardware accelerator.
*
* See AV_CODEC_ID_xxx
*/
enum AVCodecID id;
/**
* Supported pixel format.
*
* Only hardware accelerated formats are supported here.
*/
enum AVPixelFormat pix_fmt;
/**
* Hardware accelerated codec capabilities.
* see AV_HWACCEL_CODEC_CAP_*
*/
int capabilities;
} AVHWAccel;
/**
* HWAccel is experimental and is thus avoided in favor of non experimental
* codecs
*/
#define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
/**
* Hardware acceleration should be used for decoding even if the codec level
* used is unknown or higher than the maximum supported level reported by the
* hardware driver.
*
* It's generally a good idea to pass this flag unless you have a specific
* reason not to, as hardware tends to under-report supported levels.
*/
#define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
/**
* Hardware acceleration can output YUV pixel formats with a different chroma
* sampling than 4:2:0 and/or other than 8 bits per component.
*/
#define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
/**
* Hardware acceleration should still be attempted for decoding when the
* codec profile does not match the reported capabilities of the hardware.
*
* For example, this can be used to try to decode baseline profile H.264
* streams in hardware - it will often succeed, because many streams marked
* as baseline profile actually conform to constrained baseline profile.
*
* @warning If the stream is actually not supported then the behaviour is
* undefined, and may include returning entirely incorrect output
* while indicating success.
*/
#define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
/**
* Some hardware decoders (namely nvdec) can either output direct decoder
* surfaces, or make an on-device copy and return said copy.
* There is a hard limit on how many decoder surfaces there can be, and it
* cannot be accurately guessed ahead of time.
* For some processing chains, this can be okay, but others will run into the
* limit and in turn produce very confusing errors that require fine tuning of
* more or less obscure options by the user, or in extreme cases cannot be
* resolved at all without inserting an avfilter that forces a copy.
*
* Thus, the hwaccel will by default make a copy for safety and resilience.
* If a users really wants to minimize the amount of copies, they can set this
* flag and ensure their processing chain does not exhaust the surface pool.
*/
#define AV_HWACCEL_FLAG_UNSAFE_OUTPUT (1 << 3)
/**
* @}
*/
enum AVSubtitleType {
SUBTITLE_NONE,
SUBTITLE_BITMAP, ///< A bitmap, pict will be set
/**
* Plain text, the text field must be set by the decoder and is
* authoritative. ass and pict fields may contain approximations.
*/
SUBTITLE_TEXT,
/**
* Formatted text, the ass field must be set by the decoder and is
* authoritative. pict and text fields may contain approximations.
*/
SUBTITLE_ASS,
};
#define AV_SUBTITLE_FLAG_FORCED 0x00000001
typedef struct AVSubtitleRect {
int x; ///< top left corner of pict, undefined when pict is not set
int y; ///< top left corner of pict, undefined when pict is not set
int w; ///< width of pict, undefined when pict is not set
int h; ///< height of pict, undefined when pict is not set
int nb_colors; ///< number of colors in pict, undefined when pict is not set
/**
* data+linesize for the bitmap of this subtitle.
* Can be set for text/ass as well once they are rendered.
*/
uint8_t *data[4];
int linesize[4];
int flags;
enum AVSubtitleType type;
char *text; ///< 0 terminated plain UTF-8 text
/**
* 0 terminated ASS/SSA compatible event line.
* The presentation of this is unaffected by the other values in this
* struct.
*/
char *ass;
} AVSubtitleRect;
typedef struct AVSubtitle {
uint16_t format; /* 0 = graphics */
uint32_t start_display_time; /* relative to packet pts, in ms */
uint32_t end_display_time; /* relative to packet pts, in ms */
unsigned num_rects;
AVSubtitleRect **rects;
int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
} AVSubtitle;
/**
* Return the LIBAVCODEC_VERSION_INT constant.
*/
unsigned avcodec_version(void);
/**
* Return the libavcodec build-time configuration.
*/
const char *avcodec_configuration(void);
/**
* Return the libavcodec license.
*/
const char *avcodec_license(void);
/**
* Allocate an AVCodecContext and set its fields to default values. The
* resulting struct should be freed with avcodec_free_context().
*
* @param codec if non-NULL, allocate private data and initialize defaults
* for the given codec. It is illegal to then call avcodec_open2()
* with a different codec.
* If NULL, then the codec-specific defaults won't be initialized,
* which may result in suboptimal default settings (this is
* important mainly for encoders, e.g. libx264).
*
* @return An AVCodecContext filled with default values or NULL on failure.
*/
AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
/**
* Free the codec context and everything associated with it and write NULL to
* the provided pointer.
*/
void avcodec_free_context(AVCodecContext **avctx);
/**
* Get the AVClass for AVCodecContext. It can be used in combination with
* AV_OPT_SEARCH_FAKE_OBJ for examining options.
*
* @see av_opt_find().
*/
const AVClass *avcodec_get_class(void);
/**
* Get the AVClass for AVSubtitleRect. It can be used in combination with
* AV_OPT_SEARCH_FAKE_OBJ for examining options.
*
* @see av_opt_find().
*/
const AVClass *avcodec_get_subtitle_rect_class(void);
/**
* Fill the parameters struct based on the values from the supplied codec
* context. Any allocated fields in par are freed and replaced with duplicates
* of the corresponding fields in codec.
*
* @return >= 0 on success, a negative AVERROR code on failure
*/
int avcodec_parameters_from_context(struct AVCodecParameters *par,
const AVCodecContext *codec);
/**
* Fill the codec context based on the values from the supplied codec
* parameters. Any allocated fields in codec that have a corresponding field in
* par are freed and replaced with duplicates of the corresponding field in par.
* Fields in codec that do not have a counterpart in par are not touched.
*
* @return >= 0 on success, a negative AVERROR code on failure.
*/
int avcodec_parameters_to_context(AVCodecContext *codec,
const struct AVCodecParameters *par);
/**
* Initialize the AVCodecContext to use the given AVCodec. Prior to using this
* function the context has to be allocated with avcodec_alloc_context3().
*
* The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
* avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
* retrieving a codec.
*
* Depending on the codec, you might need to set options in the codec context
* also for decoding (e.g. width, height, or the pixel or audio sample format in
* the case the information is not available in the bitstream, as when decoding
* raw audio or video).
*
* Options in the codec context can be set either by setting them in the options
* AVDictionary, or by setting the values in the context itself, directly or by
* using the av_opt_set() API before calling this function.
*
* Example:
* @code
* av_dict_set(&opts, "b", "2.5M", 0);
* codec = avcodec_find_decoder(AV_CODEC_ID_H264);
* if (!codec)
* exit(1);
*
* context = avcodec_alloc_context3(codec);
*
* if (avcodec_open2(context, codec, opts) < 0)
* exit(1);
* @endcode
*
* In the case AVCodecParameters are available (e.g. when demuxing a stream
* using libavformat, and accessing the AVStream contained in the demuxer), the
* codec parameters can be copied to the codec context using
* avcodec_parameters_to_context(), as in the following example:
*
* @code
* AVStream *stream = ...;
* context = avcodec_alloc_context3(codec);
* if (avcodec_parameters_to_context(context, stream->codecpar) < 0)
* exit(1);
* if (avcodec_open2(context, codec, NULL) < 0)
* exit(1);
* @endcode
*
* @note Always call this function before using decoding routines (such as
* @ref avcodec_receive_frame()).
*
* @param avctx The context to initialize.
* @param codec The codec to open this context for. If a non-NULL codec has been
* previously passed to avcodec_alloc_context3() or
* for this context, then this parameter MUST be either NULL or
* equal to the previously passed codec.
* @param options A dictionary filled with AVCodecContext and codec-private
* options, which are set on top of the options already set in
* avctx, can be NULL. On return this object will be filled with
* options that were not found in the avctx codec context.
*
* @return zero on success, a negative value on error
* @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
* av_dict_set(), av_opt_set(), av_opt_find(), avcodec_parameters_to_context()
*/
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
#if FF_API_AVCODEC_CLOSE
/**
* Close a given AVCodecContext and free all the data associated with it
* (but not the AVCodecContext itself).
*
* Calling this function on an AVCodecContext that hasn't been opened will free
* the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
* codec. Subsequent calls will do nothing.
*
* @deprecated Do not use this function. Use avcodec_free_context() to destroy a
* codec context (either open or closed). Opening and closing a codec context
* multiple times is not supported anymore -- use multiple codec contexts
* instead.
*/
attribute_deprecated
int avcodec_close(AVCodecContext *avctx);
#endif
/**
* Free all allocated data in the given subtitle struct.
*
* @param sub AVSubtitle to free.
*/
void avsubtitle_free(AVSubtitle *sub);
/**
* @}
*/
/**
* @addtogroup lavc_decoding
* @{
*/
/**
* The default callback for AVCodecContext.get_buffer2(). It is made public so
* it can be called by custom get_buffer2() implementations for decoders without
* AV_CODEC_CAP_DR1 set.
*/
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
/**
* The default callback for AVCodecContext.get_encode_buffer(). It is made public so
* it can be called by custom get_encode_buffer() implementations for encoders without
* AV_CODEC_CAP_DR1 set.
*/
int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags);
/**
* Modify width and height values so that they will result in a memory
* buffer that is acceptable for the codec if you do not use any horizontal
* padding.
*
* May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
*/
void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
/**
* Modify width and height values so that they will result in a memory
* buffer that is acceptable for the codec if you also ensure that all
* line sizes are a multiple of the respective linesize_align[i].
*
* May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
*/
void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
int linesize_align[AV_NUM_DATA_POINTERS]);
/**
* Decode a subtitle message.
* Return a negative value on error, otherwise return the number of bytes used.
* If no subtitle could be decompressed, got_sub_ptr is zero.
* Otherwise, the subtitle is stored in *sub.
* Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
* simplicity, because the performance difference is expected to be negligible
* and reusing a get_buffer written for video codecs would probably perform badly
* due to a potentially very different allocation pattern.
*
* Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
* and output. This means that for some packets they will not immediately
* produce decoded output and need to be flushed at the end of decoding to get
* all the decoded data. Flushing is done by calling this function with packets
* with avpkt->data set to NULL and avpkt->size set to 0 until it stops
* returning subtitles. It is safe to flush even those decoders that are not
* marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
*
* @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
* before packets may be fed to the decoder.
*
* @param avctx the codec context
* @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
* must be freed with avsubtitle_free if *got_sub_ptr is set.
* @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
* @param[in] avpkt The input AVPacket containing the input buffer.
*/
int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
int *got_sub_ptr, const AVPacket *avpkt);
/**
* Supply raw packet data as input to a decoder.
*
* Internally, this call will copy relevant AVCodecContext fields, which can
* influence decoding per-packet, and apply them when the packet is actually
* decoded. (For example AVCodecContext.skip_frame, which might direct the
* decoder to drop the frame contained by the packet sent with this function.)
*
* @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
* larger than the actual read bytes because some optimized bitstream
* readers read 32 or 64 bits at once and could read over the end.
*
* @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
* before packets may be fed to the decoder.
*
* @param avctx codec context
* @param[in] avpkt The input AVPacket. Usually, this will be a single video
* frame, or several complete audio frames.
* Ownership of the packet remains with the caller, and the
* decoder will not write to the packet. The decoder may create
* a reference to the packet data (or copy it if the packet is
* not reference-counted).
* Unlike with older APIs, the packet is always fully consumed,
* and if it contains multiple frames (e.g. some audio codecs),
* will require you to call avcodec_receive_frame() multiple
* times afterwards before you can send a new packet.
* It can be NULL (or an AVPacket with data set to NULL and
* size set to 0); in this case, it is considered a flush
* packet, which signals the end of the stream. Sending the
* first flush packet will return success. Subsequent ones are
* unnecessary and will return AVERROR_EOF. If the decoder
* still has frames buffered, it will return them after sending
* a flush packet.
*
* @retval 0 success
* @retval AVERROR(EAGAIN) input is not accepted in the current state - user
* must read output with avcodec_receive_frame() (once
* all output is read, the packet should be resent,
* and the call will not fail with EAGAIN).
* @retval AVERROR_EOF the decoder has been flushed, and no new packets can be
* sent to it (also returned if more than 1 flush
* packet is sent)
* @retval AVERROR(EINVAL) codec not opened, it is an encoder, or requires flush
* @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
* @retval "another negative error code" legitimate decoding errors
*/
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
/**
* Return decoded output data from a decoder or encoder (when the
* @ref AV_CODEC_FLAG_RECON_FRAME flag is used).
*
* @param avctx codec context
* @param frame This will be set to a reference-counted video or audio
* frame (depending on the decoder type) allocated by the
* codec. Note that the function will always call
* av_frame_unref(frame) before doing anything else.
*
* @retval 0 success, a frame was returned
* @retval AVERROR(EAGAIN) output is not available in this state - user must
* try to send new input
* @retval AVERROR_EOF the codec has been fully flushed, and there will be
* no more output frames
* @retval AVERROR(EINVAL) codec not opened, or it is an encoder without the
* @ref AV_CODEC_FLAG_RECON_FRAME flag enabled
* @retval "other negative error code" legitimate decoding errors
*/
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame);
/**
* Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
* to retrieve buffered output packets.
*
* @param avctx codec context
* @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
* Ownership of the frame remains with the caller, and the
* encoder will not write to the frame. The encoder may create
* a reference to the frame data (or copy it if the frame is
* not reference-counted).
* It can be NULL, in which case it is considered a flush
* packet. This signals the end of the stream. If the encoder
* still has packets buffered, it will return them after this
* call. Once flushing mode has been entered, additional flush
* packets are ignored, and sending frames will return
* AVERROR_EOF.
*
* For audio:
* If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
* can have any number of samples.
* If it is not set, frame->nb_samples must be equal to
* avctx->frame_size for all frames except the last.
* The final frame may be smaller than avctx->frame_size.
* @retval 0 success
* @retval AVERROR(EAGAIN) input is not accepted in the current state - user must
* read output with avcodec_receive_packet() (once all
* output is read, the packet should be resent, and the
* call will not fail with EAGAIN).
* @retval AVERROR_EOF the encoder has been flushed, and no new frames can
* be sent to it
* @retval AVERROR(EINVAL) codec not opened, it is a decoder, or requires flush
* @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
* @retval "another negative error code" legitimate encoding errors
*/
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
/**
* Read encoded data from the encoder.
*
* @param avctx codec context
* @param avpkt This will be set to a reference-counted packet allocated by the
* encoder. Note that the function will always call
* av_packet_unref(avpkt) before doing anything else.
* @retval 0 success
* @retval AVERROR(EAGAIN) output is not available in the current state - user must
* try to send input
* @retval AVERROR_EOF the encoder has been fully flushed, and there will be no
* more output packets
* @retval AVERROR(EINVAL) codec not opened, or it is a decoder
* @retval "another negative error code" legitimate encoding errors
*/
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
/**
* Create and return a AVHWFramesContext with values adequate for hardware
* decoding. This is meant to get called from the get_format callback, and is
* a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
* This API is for decoding with certain hardware acceleration modes/APIs only.
*
* The returned AVHWFramesContext is not initialized. The caller must do this
* with av_hwframe_ctx_init().
*
* Calling this function is not a requirement, but makes it simpler to avoid
* codec or hardware API specific details when manually allocating frames.
*
* Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
* which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
* it unnecessary to call this function or having to care about
* AVHWFramesContext initialization at all.
*
* There are a number of requirements for calling this function:
*
* - It must be called from get_format with the same avctx parameter that was
* passed to get_format. Calling it outside of get_format is not allowed, and
* can trigger undefined behavior.
* - The function is not always supported (see description of return values).
* Even if this function returns successfully, hwaccel initialization could
* fail later. (The degree to which implementations check whether the stream
* is actually supported varies. Some do this check only after the user's
* get_format callback returns.)
* - The hw_pix_fmt must be one of the choices suggested by get_format. If the
* user decides to use a AVHWFramesContext prepared with this API function,
* the user must return the same hw_pix_fmt from get_format.
* - The device_ref passed to this function must support the given hw_pix_fmt.
* - After calling this API function, it is the user's responsibility to
* initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
* and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
* before returning from get_format (this is implied by the normal
* AVCodecContext.hw_frames_ctx API rules).
* - The AVHWFramesContext parameters may change every time time get_format is
* called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
* you are inherently required to go through this process again on every
* get_format call.
* - It is perfectly possible to call this function without actually using
* the resulting AVHWFramesContext. One use-case might be trying to reuse a
* previously initialized AVHWFramesContext, and calling this API function
* only to test whether the required frame parameters have changed.
* - Fields that use dynamically allocated values of any kind must not be set
* by the user unless setting them is explicitly allowed by the documentation.
* If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
* the new free callback must call the potentially set previous free callback.
* This API call may set any dynamically allocated fields, including the free
* callback.
*
* The function will set at least the following fields on AVHWFramesContext
* (potentially more, depending on hwaccel API):
*
* - All fields set by av_hwframe_ctx_alloc().
* - Set the format field to hw_pix_fmt.
* - Set the sw_format field to the most suited and most versatile format. (An
* implication is that this will prefer generic formats over opaque formats
* with arbitrary restrictions, if possible.)
* - Set the width/height fields to the coded frame size, rounded up to the
* API-specific minimum alignment.
* - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
* field to the number of maximum reference surfaces possible with the codec,
* plus 1 surface for the user to work (meaning the user can safely reference
* at most 1 decoded surface at a time), plus additional buffering introduced
* by frame threading. If the hwaccel does not require pre-allocation, the
* field is left to 0, and the decoder will allocate new surfaces on demand
* during decoding.
* - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
* hardware API.
*
* Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
* with basic frame parameters set.
*
* The function is stateless, and does not change the AVCodecContext or the
* device_ref AVHWDeviceContext.
*
* @param avctx The context which is currently calling get_format, and which
* implicitly contains all state needed for filling the returned
* AVHWFramesContext properly.
* @param device_ref A reference to the AVHWDeviceContext describing the device
* which will be used by the hardware decoder.
* @param hw_pix_fmt The hwaccel format you are going to return from get_format.
* @param out_frames_ref On success, set to a reference to an _uninitialized_
* AVHWFramesContext, created from the given device_ref.
* Fields will be set to values required for decoding.
* Not changed if an error is returned.
* @return zero on success, a negative value on error. The following error codes
* have special semantics:
* AVERROR(ENOENT): the decoder does not support this functionality. Setup
* is always manual, or it is a decoder which does not
* support setting AVCodecContext.hw_frames_ctx at all,
* or it is a software format.
* AVERROR(EINVAL): it is known that hardware decoding is not supported for
* this configuration, or the device_ref is not supported
* for the hwaccel referenced by hw_pix_fmt.
*/
int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
AVBufferRef *device_ref,
enum AVPixelFormat hw_pix_fmt,
AVBufferRef **out_frames_ref);
/**
* @defgroup lavc_parsing Frame parsing
* @{
*/
enum AVPictureStructure {
AV_PICTURE_STRUCTURE_UNKNOWN, ///< unknown
AV_PICTURE_STRUCTURE_TOP_FIELD, ///< coded as top field
AV_PICTURE_STRUCTURE_BOTTOM_FIELD, ///< coded as bottom field
AV_PICTURE_STRUCTURE_FRAME, ///< coded as frame
};
typedef struct AVCodecParserContext {
void *priv_data;
const struct AVCodecParser *parser;
int64_t frame_offset; /* offset of the current frame */
int64_t cur_offset; /* current offset
(incremented by each av_parser_parse()) */
int64_t next_frame_offset; /* offset of the next frame */
/* video info */
int pict_type; /* XXX: Put it back in AVCodecContext. */
/**
* This field is used for proper frame duration computation in lavf.
* It signals, how much longer the frame duration of the current frame
* is compared to normal frame duration.
*
* frame_duration = (1 + repeat_pict) * time_base
*
* It is used by codecs like H.264 to display telecined material.
*/
int repeat_pict; /* XXX: Put it back in AVCodecContext. */
int64_t pts; /* pts of the current frame */
int64_t dts; /* dts of the current frame */
/* private data */
int64_t last_pts;
int64_t last_dts;
int fetch_timestamp;
#define AV_PARSER_PTS_NB 4
int cur_frame_start_index;
int64_t cur_frame_offset[AV_PARSER_PTS_NB];
int64_t cur_frame_pts[AV_PARSER_PTS_NB];
int64_t cur_frame_dts[AV_PARSER_PTS_NB];
int flags;
#define PARSER_FLAG_COMPLETE_FRAMES 0x0001
#define PARSER_FLAG_ONCE 0x0002
/// Set if the parser has a valid file offset
#define PARSER_FLAG_FETCHED_OFFSET 0x0004
#define PARSER_FLAG_USE_CODEC_TS 0x1000
int64_t offset; ///< byte offset from starting packet start
int64_t cur_frame_end[AV_PARSER_PTS_NB];
/**
* Set by parser to 1 for key frames and 0 for non-key frames.
* It is initialized to -1, so if the parser doesn't set this flag,
* old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
* will be used.
*/
int key_frame;
// Timestamp generation support:
/**
* Synchronization point for start of timestamp generation.
*
* Set to >0 for sync point, 0 for no sync point and <0 for undefined
* (default).
*
* For example, this corresponds to presence of H.264 buffering period
* SEI message.
*/
int dts_sync_point;
/**
* Offset of the current timestamp against last timestamp sync point in
* units of AVCodecContext.time_base.
*
* Set to INT_MIN when dts_sync_point unused. Otherwise, it must
* contain a valid timestamp offset.
*
* Note that the timestamp of sync point has usually a nonzero
* dts_ref_dts_delta, which refers to the previous sync point. Offset of
* the next frame after timestamp sync point will be usually 1.
*
* For example, this corresponds to H.264 cpb_removal_delay.
*/
int dts_ref_dts_delta;
/**
* Presentation delay of current frame in units of AVCodecContext.time_base.
*
* Set to INT_MIN when dts_sync_point unused. Otherwise, it must
* contain valid non-negative timestamp delta (presentation time of a frame
* must not lie in the past).
*
* This delay represents the difference between decoding and presentation
* time of the frame.
*
* For example, this corresponds to H.264 dpb_output_delay.
*/
int pts_dts_delta;
/**
* Position of the packet in file.
*
* Analogous to cur_frame_pts/dts
*/
int64_t cur_frame_pos[AV_PARSER_PTS_NB];
/**
* Byte position of currently parsed frame in stream.
*/
int64_t pos;
/**
* Previous frame byte position.
*/
int64_t last_pos;
/**
* Duration of the current frame.
* For audio, this is in units of 1 / AVCodecContext.sample_rate.
* For all other types, this is in units of AVCodecContext.time_base.
*/
int duration;
enum AVFieldOrder field_order;
/**
* Indicate whether a picture is coded as a frame, top field or bottom field.
*
* For example, H.264 field_pic_flag equal to 0 corresponds to
* AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
* equal to 1 and bottom_field_flag equal to 0 corresponds to
* AV_PICTURE_STRUCTURE_TOP_FIELD.
*/
enum AVPictureStructure picture_structure;
/**
* Picture number incremented in presentation or output order.
* This field may be reinitialized at the first picture of a new sequence.
*
* For example, this corresponds to H.264 PicOrderCnt.
*/
int output_picture_number;
/**
* Dimensions of the decoded video intended for presentation.
*/
int width;
int height;
/**
* Dimensions of the coded video.
*/
int coded_width;
int coded_height;
/**
* The format of the coded data, corresponds to enum AVPixelFormat for video
* and for enum AVSampleFormat for audio.
*
* Note that a decoder can have considerable freedom in how exactly it
* decodes the data, so the format reported here might be different from the
* one returned by a decoder.
*/
int format;
} AVCodecParserContext;
typedef struct AVCodecParser {
int codec_ids[7]; /* several codec IDs are permitted */
int priv_data_size;
int (*parser_init)(AVCodecParserContext *s);
/* This callback never returns an error, a negative value means that
* the frame start was in a previous packet. */
int (*parser_parse)(AVCodecParserContext *s,
AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size);
void (*parser_close)(AVCodecParserContext *s);
int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
} AVCodecParser;
/**
* Iterate over all registered codec parsers.
*
* @param opaque a pointer where libavcodec will store the iteration state. Must
* point to NULL to start the iteration.
*
* @return the next registered codec parser or NULL when the iteration is
* finished
*/
const AVCodecParser *av_parser_iterate(void **opaque);
AVCodecParserContext *av_parser_init(int codec_id);
/**
* Parse a packet.
*
* @param s parser context.
* @param avctx codec context.
* @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
* @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
* @param buf input buffer.
* @param buf_size buffer size in bytes without the padding. I.e. the full buffer
size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
To signal EOF, this should be 0 (so that the last frame
can be output).
* @param pts input presentation timestamp.
* @param dts input decoding timestamp.
* @param pos input byte position in stream.
* @return the number of bytes of the input bitstream used.
*
* Example:
* @code
* while(in_len){
* len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
* in_data, in_len,
* pts, dts, pos);
* in_data += len;
* in_len -= len;
*
* if(size)
* decode_frame(data, size);
* }
* @endcode
*/
int av_parser_parse2(AVCodecParserContext *s,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size,
int64_t pts, int64_t dts,
int64_t pos);
void av_parser_close(AVCodecParserContext *s);
/**
* @}
* @}
*/
/**
* @addtogroup lavc_encoding
* @{
*/
int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
const AVSubtitle *sub);
/**
* @}
*/
/**
* @defgroup lavc_misc Utility functions
* @ingroup libavc
*
* Miscellaneous utility functions related to both encoding and decoding
* (or neither).
* @{
*/
/**
* @defgroup lavc_misc_pixfmt Pixel formats
*
* Functions for working with pixel formats.
* @{
*/
/**
* Return a value representing the fourCC code associated to the
* pixel format pix_fmt, or 0 if no associated fourCC code can be
* found.
*/
unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
/**
* Find the best pixel format to convert to given a certain source pixel
* format. When converting from one pixel format to another, information loss
* may occur. For example, when converting from RGB24 to GRAY, the color
* information will be lost. Similarly, other losses occur when converting from
* some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
* the given pixel formats should be used to suffer the least amount of loss.
* The pixel formats from which it chooses one, are determined by the
* pix_fmt_list parameter.
*
*
* @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
* @param[in] src_pix_fmt source pixel format
* @param[in] has_alpha Whether the source pixel format alpha channel is used.
* @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
* @return The best pixel format to convert to or -1 if none was found.
*/
enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
enum AVPixelFormat src_pix_fmt,
int has_alpha, int *loss_ptr);
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
/**
* @}
*/
void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
//FIXME func typedef
/**
* Fill AVFrame audio data and linesize pointers.
*
* The buffer buf must be a preallocated buffer with a size big enough
* to contain the specified samples amount. The filled AVFrame data
* pointers will point to this buffer.
*
* AVFrame extended_data channel pointers are allocated if necessary for
* planar audio.
*
* @param frame the AVFrame
* frame->nb_samples must be set prior to calling the
* function. This function fills in frame->data,
* frame->extended_data, frame->linesize[0].
* @param nb_channels channel count
* @param sample_fmt sample format
* @param buf buffer to use for frame data
* @param buf_size size of buffer
* @param align plane size sample alignment (0 = default)
* @return >=0 on success, negative error code on failure
* @todo return the size in bytes required to store the samples in
* case of success, at the next libavutil bump
*/
int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
enum AVSampleFormat sample_fmt, const uint8_t *buf,
int buf_size, int align);
/**
* Reset the internal codec state / flush internal buffers. Should be called
* e.g. when seeking or when switching to a different stream.
*
* @note for decoders, this function just releases any references the decoder
* might keep internally, but the caller's references remain valid.
*
* @note for encoders, this function will only do something if the encoder
* declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
* will drain any remaining packets, and can then be re-used for a different
* stream (as opposed to sending a null frame which will leave the encoder
* in a permanent EOF state after draining). This can be desirable if the
* cost of tearing down and replacing the encoder instance is high.
*/
void avcodec_flush_buffers(AVCodecContext *avctx);
/**
* Return audio frame duration.
*
* @param avctx codec context
* @param frame_bytes size of the frame, or 0 if unknown
* @return frame duration, in samples, if known. 0 if not able to
* determine.
*/
int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
/* memory */
/**
* Same behaviour av_fast_malloc but the buffer has additional
* AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
*
* In addition the whole buffer will initially and after resizes
* be 0-initialized so that no uninitialized data will ever appear.
*/
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
/**
* Same behaviour av_fast_padded_malloc except that buffer will always
* be 0-initialized after call.
*/
void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
/**
* @return a positive value if s is open (i.e. avcodec_open2() was called on it
* with no corresponding avcodec_close()), 0 otherwise.
*/
int avcodec_is_open(AVCodecContext *s);
/**
* @}
*/
#endif /* AVCODEC_AVCODEC_H */
Reference in New Issue View Git Blame Copy Permalink