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ffmpeg/libavcodec/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.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)
#define AV_CODEC_CAP_TRUNCATED (1 << 3)
/**
* 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)
/**
* 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)
/**
* 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)
#if FF_API_AUTO_THREADS
#define AV_CODEC_CAP_AUTO_THREADS AV_CODEC_CAP_OTHER_THREADS
#endif
/**
* 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)
#if FF_API_UNUSED_CODEC_CAPS
/**
* Deprecated and unused. Use AVCodecDescriptor.props instead
*/
#define AV_CODEC_CAP_INTRA_ONLY 0x40000000
/**
* Deprecated and unused. Use AVCodecDescriptor.props instead
*/
#define AV_CODEC_CAP_LOSSLESS 0x80000000
#endif
/**
* 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 codec takes the reordered_opaque field from input AVFrames
* and returns it in the corresponding field in AVCodecContext after
* encoding.
*/
#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)
/**
* AVProfile.
*/
typedef struct AVProfile {
int profile;
const char *name; ///< short name for the profile
} AVProfile;
typedef struct AVCodecDefault AVCodecDefault;
struct AVCodecContext;
struct AVSubtitle;
struct AVPacket;
/**
* 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;
const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
const AVClass *priv_class; ///< AVClass for the private context
const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_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;
/*****************************************************************
* No fields below this line are part of the public API. They
* may not be used outside of libavcodec and can be changed and
* removed at will.
* New public fields should be added right above.
*****************************************************************
*/
int priv_data_size;
/**
* @name Frame-level threading support functions
* @{
*/
/**
* Copy necessary context variables from a previous thread context to the current one.
* If not defined, the next thread will start automatically; otherwise, the codec
* must call ff_thread_finish_setup().
*
* dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
*/
int (*update_thread_context)(struct AVCodecContext *dst, const struct AVCodecContext *src);
/**
* Copy variables back to the user-facing context
*/
int (*update_thread_context_for_user)(struct AVCodecContext *dst, const struct AVCodecContext *src);
/** @} */
/**
* Private codec-specific defaults.
*/
const AVCodecDefault *defaults;
/**
* Initialize codec static data, called from av_codec_iterate().
*
* This is not intended for time consuming operations as it is
* run for every codec regardless of that codec being used.
*/
void (*init_static_data)(struct AVCodec *codec);
int (*init)(struct AVCodecContext *);
int (*encode_sub)(struct AVCodecContext *, uint8_t *buf, int buf_size,
const struct AVSubtitle *sub);
/**
* Encode data to an AVPacket.
*
* @param avctx codec context
* @param avpkt output AVPacket
* @param[in] frame AVFrame containing the raw data to be encoded
* @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
* non-empty packet was returned in avpkt.
* @return 0 on success, negative error code on failure
*/
int (*encode2)(struct AVCodecContext *avctx, struct AVPacket *avpkt,
const struct AVFrame *frame, int *got_packet_ptr);
/**
* Decode picture or subtitle data.
*
* @param avctx codec context
* @param outdata codec type dependent output struct
* @param[out] got_frame_ptr decoder sets to 0 or 1 to indicate that a
* non-empty frame or subtitle was returned in
* outdata.
* @param[in] avpkt AVPacket containing the data to be decoded
* @return amount of bytes read from the packet on success, negative error
* code on failure
*/
int (*decode)(struct AVCodecContext *avctx, void *outdata,
int *got_frame_ptr, struct AVPacket *avpkt);
int (*close)(struct AVCodecContext *);
/**
* Encode API with decoupled frame/packet dataflow. This function is called
* to get one output packet. It should call ff_encode_get_frame() to obtain
* input data.
*/
int (*receive_packet)(struct AVCodecContext *avctx, struct AVPacket *avpkt);
/**
* Decode API with decoupled packet/frame dataflow. This function is called
* to get one output frame. It should call ff_decode_get_packet() to obtain
* input data.
*/
int (*receive_frame)(struct AVCodecContext *avctx, struct AVFrame *frame);
/**
* Flush buffers.
* Will be called when seeking
*/
void (*flush)(struct AVCodecContext *);
/**
* Internal codec capabilities.
* See FF_CODEC_CAP_* in internal.h
*/
int caps_internal;
/**
* Decoding only, a comma-separated list of bitstream filters to apply to
* packets before decoding.
*/
const char *bsfs;
/**
* Array of pointers to hardware configurations supported by the codec,
* or NULL if no hardware supported. The array is terminated by a NULL
* pointer.
*
* The user can only access this field via avcodec_get_hw_config().
*/
const struct AVCodecHWConfigInternal *const *hw_configs;
/**
* List of supported codec_tags, terminated by FF_CODEC_TAGS_END.
*/
const uint32_t *codec_tags;
} 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 */
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