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/*
* generic decoding-related code
*
* 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_DECODE_H
#define AVCODEC_DECODE_H
#include "libavutil/frame.h"
#include "libavutil/hwcontext.h"
#include "avcodec.h"
/**
* This struct stores per-frame lavc-internal data and is attached to it via
* private_ref.
*/
typedef struct FrameDecodeData {
/**
* The callback to perform some delayed processing on the frame right
* before it is returned to the caller.
*
* @note This code is called at some unspecified point after the frame is
* returned from the decoder's decode/receive_frame call. Therefore it cannot rely
* on AVCodecContext being in any specific state, so it does not get to
* access AVCodecContext directly at all. All the state it needs must be
* stored in the post_process_opaque object.
*/
int (*post_process)(void *logctx, AVFrame *frame);
void *post_process_opaque;
void (*post_process_opaque_free)(void *opaque);
/**
* Per-frame private data for hwaccels.
*/
void *hwaccel_priv;
void (*hwaccel_priv_free)(void *priv);
} FrameDecodeData;
/**
* Called by decoders to get the next packet for decoding.
*
* @param pkt An empty packet to be filled with data.
* @return 0 if a new reference has been successfully written to pkt
* AVERROR(EAGAIN) if no data is currently available
* AVERROR_EOF if and end of stream has been reached, so no more data
* will be available
*/
int ff_decode_get_packet(AVCodecContext *avctx, AVPacket *pkt);
/**
* Set various frame properties from the provided packet.
*/
int ff_decode_frame_props_from_pkt(const AVCodecContext *avctx,
AVFrame *frame, const AVPacket *pkt);
/**
* Set various frame properties from the codec context / packet data.
*/
int ff_decode_frame_props(AVCodecContext *avctx, AVFrame *frame);
/**
* Make sure avctx.hw_frames_ctx is set. If it's not set, the function will
* try to allocate it from hw_device_ctx. If that is not possible, an error
* message is printed, and an error code is returned.
*/
int ff_decode_get_hw_frames_ctx(AVCodecContext *avctx,
enum AVHWDeviceType dev_type);
int ff_attach_decode_data(AVFrame *frame);
/**
* Check whether the side-data of src contains a palette of
* size AVPALETTE_SIZE; if so, copy it to dst and return 1;
* else return 0.
* Also emit an error message upon encountering a palette
* with invalid size.
*/
int ff_copy_palette(void *dst, const AVPacket *src, void *logctx);
/**
* Check that the provided frame dimensions are valid and set them on the codec
* context.
*/
int ff_set_dimensions(AVCodecContext *s, int width, int height);
/**
* Check that the provided sample aspect ratio is valid and set it on the codec
* context.
*/
int ff_set_sar(AVCodecContext *avctx, AVRational sar);
/**
* Select the (possibly hardware accelerated) pixel format.
* This is a wrapper around AVCodecContext.get_format() and should be used
* instead of calling get_format() directly.
*
* The list of pixel formats must contain at least one valid entry, and is
* terminated with AV_PIX_FMT_NONE. If it is possible to decode to software,
* the last entry in the list must be the most accurate software format.
* If it is not possible to decode to software, AVCodecContext.sw_pix_fmt
* must be set before calling this function.
*/
int ff_get_format(AVCodecContext *avctx, const enum AVPixelFormat *fmt);
/**
* Get a buffer for a frame. This is a wrapper around
* AVCodecContext.get_buffer() and should be used instead calling get_buffer()
* directly.
*/
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags);
#define FF_REGET_BUFFER_FLAG_READONLY 1 ///< the returned buffer does not need to be writable
/**
* Identical in function to ff_get_buffer(), except it reuses the existing buffer
* if available.
*/
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags);
/**
* Add or update AV_FRAME_DATA_MATRIXENCODING side data.
*/
int ff_side_data_update_matrix_encoding(AVFrame *frame,
enum AVMatrixEncoding matrix_encoding);
/**
* Allocate a hwaccel frame private data if the provided avctx
* uses a hwaccel method that needs it. The returned data is
* a RefStruct reference (if allocated).
*
* @param avctx The codec context
* @param hwaccel_picture_private Pointer to return hwaccel_picture_private
* @return 0 on success, < 0 on error
*/
int ff_hwaccel_frame_priv_alloc(AVCodecContext *avctx, void **hwaccel_picture_private);
/**
* Get side data of the given type from a decoding context.
*/
const AVPacketSideData *ff_get_coded_side_data(const AVCodecContext *avctx,
enum AVPacketSideDataType type);
#endif /* AVCODEC_DECODE_H */