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codec.h
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/*
* AVCodec public API
*
* 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_CODEC_H
#define AVCODEC_CODEC_H
#include <stdint.h>
#include "libavutil/avutil.h"
#include "libavutil/hwcontext.h"
#include "libavutil/log.h"
#include "libavutil/pixfmt.h"
#include "libavutil/rational.h"
#include "libavutil/samplefmt.h"
#include "libavcodec/codec_id.h"
#include "libavcodec/version_major.h"
/**
* @addtogroup lavc_core
* @{
*/
/**
* Decoder can use draw_horiz_band callback.
*/
#define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
/**
* Codec uses get_buffer() or get_encode_buffer() for allocating buffers and
* supports custom allocators.
* If not set, it might not use get_buffer() or get_encode_buffer() at all, or
* use operations that assume the buffer was allocated by
* avcodec_default_get_buffer2 or avcodec_default_get_encode_buffer.
*/
#define AV_CODEC_CAP_DR1 (1 << 1)
/**
* Encoder or decoder requires flushing with NULL input at the end in order to
* give the complete and correct output.
*
* NOTE: If this flag is not set, the codec is guaranteed to never be fed with
* with NULL data. The user can still send NULL data to the public encode
* or decode function, but libavcodec will not pass it along to the codec
* unless this flag is set.
*
* Decoders:
* The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
* avpkt->size=0 at the end to get the delayed data until the decoder no longer
* returns frames.
*
* Encoders:
* The encoder needs to be fed with NULL data at the end of encoding until the
* encoder no longer returns data.
*
* NOTE: For encoders implementing the AVCodec.encode2() function, setting this
* flag also means that the encoder must set the pts and duration for
* each output packet. If this flag is not set, the pts and duration will
* be determined by libavcodec from the input frame.
*/
#define AV_CODEC_CAP_DELAY (1 << 5)
/**
* Codec can be fed a final frame with a smaller size.
* This can be used to prevent truncation of the last audio samples.
*/
#define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
#if FF_API_SUBFRAMES
/**
* Codec can output multiple frames per AVPacket
* Normally demuxers return one frame at a time, demuxers which do not do
* are connected to a parser to split what they return into proper frames.
* This flag is reserved to the very rare category of codecs which have a
* bitstream that cannot be split into frames without timeconsuming
* operations like full decoding. Demuxers carrying such bitstreams thus
* may return multiple frames in a packet. This has many disadvantages like
* prohibiting stream copy in many cases thus it should only be considered
* as a last resort.
*/
#define AV_CODEC_CAP_SUBFRAMES (1 << 8)
#endif
/**
* Codec is experimental and is thus avoided in favor of non experimental
* encoders
*/
#define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
/**
* Codec should fill in channel configuration and samplerate instead of container
*/
#define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
/**
* Codec supports frame-level multithreading.
*/
#define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
/**
* Codec supports slice-based (or partition-based) multithreading.
*/
#define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
/**
* Codec supports changed parameters at any point.
*/
#define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
/**
* Codec supports multithreading through a method other than slice- or
* frame-level multithreading. Typically this marks wrappers around
* multithreading-capable external libraries.
*/
#define AV_CODEC_CAP_OTHER_THREADS (1 << 15)
/**
* Audio encoder supports receiving a different number of samples in each call.
*/
#define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
/**
* Decoder is not a preferred choice for probing.
* This indicates that the decoder is not a good choice for probing.
* It could for example be an expensive to spin up hardware decoder,
* or it could simply not provide a lot of useful information about
* the stream.
* A decoder marked with this flag should only be used as last resort
* choice for probing.
*/
#define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
/**
* Codec is backed by a hardware implementation. Typically used to
* identify a non-hwaccel hardware decoder. For information about hwaccels, use
* avcodec_get_hw_config() instead.
*/
#define AV_CODEC_CAP_HARDWARE (1 << 18)
/**
* Codec is potentially backed by a hardware implementation, but not
* necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
* implementation provides some sort of internal fallback.
*/
#define AV_CODEC_CAP_HYBRID (1 << 19)
/**
* This encoder can reorder user opaque values from input AVFrames and return
* them with corresponding output packets.
* @see AV_CODEC_FLAG_COPY_OPAQUE
*/
#define AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE (1 << 20)
/**
* This encoder can be flushed using avcodec_flush_buffers(). If this flag is
* not set, the encoder must be closed and reopened to ensure that no frames
* remain pending.
*/
#define AV_CODEC_CAP_ENCODER_FLUSH (1 << 21)
/**
* The encoder is able to output reconstructed frame data, i.e. raw frames that
* would be produced by decoding the encoded bitstream.
*
* Reconstructed frame output is enabled by the AV_CODEC_FLAG_RECON_FRAME flag.
*/
#define AV_CODEC_CAP_ENCODER_RECON_FRAME (1 << 22)
/**
* AVProfile.
*/
typedef struct AVProfile {
int profile;
const char *name; ///< short name for the profile
} AVProfile;
/**
* AVCodec.
*/
typedef struct AVCodec {
/**
* Name of the codec implementation.
* The name is globally unique among encoders and among decoders (but an
* encoder and a decoder can share the same name).
* This is the primary way to find a codec from the user perspective.
*/
const char *name;
/**
* Descriptive name for the codec, meant to be more human readable than name.
* You should use the NULL_IF_CONFIG_SMALL() macro to define it.
*/
const char *long_name;
enum AVMediaType type;
enum AVCodecID id;
/**
* Codec capabilities.
* see AV_CODEC_CAP_*
*/
int capabilities;
uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
/**
* Deprecated codec capabilities.
*/
attribute_deprecated
const AVRational *supported_framerates; ///< @deprecated use avcodec_get_supported_config()
attribute_deprecated
const enum AVPixelFormat *pix_fmts; ///< @deprecated use avcodec_get_supported_config()
attribute_deprecated
const int *supported_samplerates; ///< @deprecated use avcodec_get_supported_config()
attribute_deprecated
const enum AVSampleFormat *sample_fmts; ///< @deprecated use avcodec_get_supported_config()
const AVClass *priv_class; ///< AVClass for the private context
const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {AV_PROFILE_UNKNOWN}
/**
* Group name of the codec implementation.
* This is a short symbolic name of the wrapper backing this codec. A
* wrapper uses some kind of external implementation for the codec, such
* as an external library, or a codec implementation provided by the OS or
* the hardware.
* If this field is NULL, this is a builtin, libavcodec native codec.
* If non-NULL, this will be the suffix in AVCodec.name in most cases
* (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
*/
const char *wrapper_name;
/**
* Array of supported channel layouts, terminated with a zeroed layout.
* @deprecated use avcodec_get_supported_config()
*/
attribute_deprecated
const AVChannelLayout *ch_layouts;
} AVCodec;
/**
* Iterate over all registered codecs.
*
* @param opaque a pointer where libavcodec will store the iteration state. Must
* point to NULL to start the iteration.
*
* @return the next registered codec or NULL when the iteration is
* finished
*/
const AVCodec *av_codec_iterate(void **opaque);
/**
* Find a registered decoder with a matching codec ID.
*
* @param id AVCodecID of the requested decoder
* @return A decoder if one was found, NULL otherwise.
*/
const AVCodec *avcodec_find_decoder(enum AVCodecID id);
/**
* Find a registered decoder with the specified name.
*
* @param name name of the requested decoder
* @return A decoder if one was found, NULL otherwise.
*/
const AVCodec *avcodec_find_decoder_by_name(const char *name);
/**
* Find a registered encoder with a matching codec ID.
*
* @param id AVCodecID of the requested encoder
* @return An encoder if one was found, NULL otherwise.
*/
const AVCodec *avcodec_find_encoder(enum AVCodecID id);
/**
* Find a registered encoder with the specified name.
*
* @param name name of the requested encoder
* @return An encoder if one was found, NULL otherwise.
*/
const AVCodec *avcodec_find_encoder_by_name(const char *name);
/**
* @return a non-zero number if codec is an encoder, zero otherwise
*/
int av_codec_is_encoder(const AVCodec *codec);
/**
* @return a non-zero number if codec is a decoder, zero otherwise
*/
int av_codec_is_decoder(const AVCodec *codec);
/**
* Return a name for the specified profile, if available.
*
* @param codec the codec that is searched for the given profile
* @param profile the profile value for which a name is requested
* @return A name for the profile if found, NULL otherwise.
*/
const char *av_get_profile_name(const AVCodec *codec, int profile);
enum {
/**
* The codec supports this format via the hw_device_ctx interface.
*
* When selecting this format, AVCodecContext.hw_device_ctx should
* have been set to a device of the specified type before calling
* avcodec_open2().
*/
AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX = 0x01,
/**
* The codec supports this format via the hw_frames_ctx interface.
*
* When selecting this format for a decoder,
* AVCodecContext.hw_frames_ctx should be set to a suitable frames
* context inside the get_format() callback. The frames context
* must have been created on a device of the specified type.
*
* When selecting this format for an encoder,
* AVCodecContext.hw_frames_ctx should be set to the context which
* will be used for the input frames before calling avcodec_open2().
*/
AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX = 0x02,
/**
* The codec supports this format by some internal method.
*
* This format can be selected without any additional configuration -
* no device or frames context is required.
*/
AV_CODEC_HW_CONFIG_METHOD_INTERNAL = 0x04,
/**
* The codec supports this format by some ad-hoc method.
*
* Additional settings and/or function calls are required. See the
* codec-specific documentation for details. (Methods requiring
* this sort of configuration are deprecated and others should be
* used in preference.)
*/
AV_CODEC_HW_CONFIG_METHOD_AD_HOC = 0x08,
};
typedef struct AVCodecHWConfig {
/**
* For decoders, a hardware pixel format which that decoder may be
* able to decode to if suitable hardware is available.
*
* For encoders, a pixel format which the encoder may be able to
* accept. If set to AV_PIX_FMT_NONE, this applies to all pixel
* formats supported by the codec.
*/
enum AVPixelFormat pix_fmt;
/**
* Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
* setup methods which can be used with this configuration.
*/
int methods;
/**
* The device type associated with the configuration.
*
* Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
* AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
*/
enum AVHWDeviceType device_type;
} AVCodecHWConfig;
/**
* Retrieve supported hardware configurations for a codec.
*
* Values of index from zero to some maximum return the indexed configuration
* descriptor; all other values return NULL. If the codec does not support
* any hardware configurations then it will always return NULL.
*/
const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
/**
* @}
*/
#endif /* AVCODEC_CODEC_H */
attribute_deprecated
#define attribute_deprecated
Definition attributes.h:100
avutil.h
Convenience header that includes libavutil's core.
codec_id.h
av_codec_is_encoder
int av_codec_is_encoder(const AVCodec *codec)
av_codec_is_decoder
int av_codec_is_decoder(const AVCodec *codec)
avcodec_find_decoder
const AVCodec * avcodec_find_decoder(enum AVCodecID id)
Find a registered decoder with a matching codec ID.
avcodec_find_decoder_by_name
const AVCodec * avcodec_find_decoder_by_name(const char *name)
Find a registered decoder with the specified name.
avcodec_find_encoder
const AVCodec * avcodec_find_encoder(enum AVCodecID id)
Find a registered encoder with a matching codec ID.
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition codec_id.h:49
avcodec_get_hw_config
const AVCodecHWConfig * avcodec_get_hw_config(const AVCodec *codec, int index)
Retrieve supported hardware configurations for a codec.
avcodec_find_encoder_by_name
const AVCodec * avcodec_find_encoder_by_name(const char *name)
Find a registered encoder with the specified name.
av_codec_iterate
const AVCodec * av_codec_iterate(void **opaque)
Iterate over all registered codecs.
av_get_profile_name
const char * av_get_profile_name(const AVCodec *codec, int profile)
Return a name for the specified profile, if available.
AV_CODEC_HW_CONFIG_METHOD_AD_HOC
@ AV_CODEC_HW_CONFIG_METHOD_AD_HOC
The codec supports this format by some ad-hoc method.
Definition codec.h:342
AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX
@ AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX
The codec supports this format via the hw_frames_ctx interface.
Definition codec.h:326
AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX
@ AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX
The codec supports this format via the hw_device_ctx interface.
Definition codec.h:313
AV_CODEC_HW_CONFIG_METHOD_INTERNAL
@ AV_CODEC_HW_CONFIG_METHOD_INTERNAL
The codec supports this format by some internal method.
Definition codec.h:333
AVMediaType
AVMediaType
Definition avutil.h:199
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition samplefmt.h:55
hwcontext.h
AVHWDeviceType
AVHWDeviceType
Definition hwcontext.h:27
version_major.h
Libavcodec version macros.
log.h
pixfmt.h
pixel format definitions
AVPixelFormat
AVPixelFormat
Pixel format.
Definition pixfmt.h:71
rational.h
Utilties for rational number calculation.
samplefmt.h
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition channel_layout.h:311
AVClass
Describe the class of an AVClass context structure.
Definition log.h:66
AVCodecHWConfig
Definition codec.h:345
AVCodecHWConfig::device_type
enum AVHWDeviceType device_type
The device type associated with the configuration.
Definition codec.h:366
AVCodecHWConfig::methods
int methods
Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible setup methods which can be used...
Definition codec.h:359
AVCodecHWConfig::pix_fmt
enum AVPixelFormat pix_fmt
For decoders, a hardware pixel format which that decoder may be able to decode to if suitable hardwar...
Definition codec.h:354
AVCodec
AVCodec.
Definition codec.h:187
AVCodec::id
enum AVCodecID id
Definition codec.h:201
AVCodec::pix_fmts
attribute_deprecated enum AVPixelFormat * pix_fmts
Definition codec.h:215
AVCodec::ch_layouts
attribute_deprecated const AVChannelLayout * ch_layouts
Array of supported channel layouts, terminated with a zeroed layout.
Definition codec.h:241
AVCodec::supported_framerates
attribute_deprecated const AVRational * supported_framerates
Deprecated codec capabilities.
Definition codec.h:213
AVCodec::priv_class
const AVClass * priv_class
AVClass for the private context.
Definition codec.h:221
AVCodec::supported_samplerates
attribute_deprecated const int * supported_samplerates
Definition codec.h:217
AVCodec::sample_fmts
attribute_deprecated enum AVSampleFormat * sample_fmts
Definition codec.h:219
AVCodec::type
enum AVMediaType type
Definition codec.h:200
AVCodec::profiles
const AVProfile * profiles
array of recognized profiles, or NULL if unknown, array is terminated by {AV_PROFILE_UNKNOWN}
Definition codec.h:222
AVCodec::long_name
const char * long_name
Descriptive name for the codec, meant to be more human readable than name.
Definition codec.h:199
AVCodec::wrapper_name
const char * wrapper_name
Group name of the codec implementation.
Definition codec.h:234
AVCodec::name
const char * name
Name of the codec implementation.
Definition codec.h:194
AVCodec::capabilities
int capabilities
Codec capabilities.
Definition codec.h:206
AVCodec::max_lowres
uint8_t max_lowres
maximum value for lowres supported by the decoder
Definition codec.h:207
AVProfile
AVProfile.
Definition codec.h:179
AVProfile::profile
int profile
Definition codec.h:180
AVProfile::name
const char * name
short name for the profile
Definition codec.h:181
AVRational
Rational number (pair of numerator and denominator).
Definition rational.h:58