ffmpeg/libavfilter/buffersrc.h

145 lines
4.5 KiB
C

/*
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVFILTER_BUFFERSRC_H
#define AVFILTER_BUFFERSRC_H
/**
* @file
* @ingroup lavfi_buffersrc
* Memory buffer source API.
*/
#include "avfilter.h"
/**
* @defgroup lavfi_buffersrc Buffer source API
* @ingroup lavfi
* @{
*/
/**
* This structure contains the parameters describing the frames that will be
* passed to this filter.
*
* It should be allocated with av_buffersrc_parameters_alloc() and freed with
* av_free(). All the allocated fields in it remain owned by the caller.
*/
typedef struct AVBufferSrcParameters {
/**
* video: the pixel format, value corresponds to enum AVPixelFormat
* audio: the sample format, value corresponds to enum AVSampleFormat
*/
int format;
/**
* The timebase to be used for the timestamps on the input frames.
*/
AVRational time_base;
/**
* Video only, the display dimensions of the input frames.
*/
int width, height;
/**
* Video only, the sample (pixel) aspect ratio.
*/
AVRational sample_aspect_ratio;
/**
* Video only, the frame rate of the input video. This field must only be
* set to a non-zero value if input stream has a known constant framerate
* and should be left at its initial value if the framerate is variable or
* unknown.
*/
AVRational frame_rate;
/**
* Video with a hwaccel pixel format only. This should be a reference to an
* AVHWFramesContext instance describing the input frames.
*/
AVBufferRef *hw_frames_ctx;
/**
* Audio only, the audio sampling rate in samples per secon.
*/
int sample_rate;
/**
* Audio only, the audio channel layout
*/
uint64_t channel_layout;
} AVBufferSrcParameters;
/**
* Allocate a new AVBufferSrcParameters instance. It should be freed by the
* caller with av_free().
*/
AVBufferSrcParameters *av_buffersrc_parameters_alloc(void);
/**
* Initialize the buffersrc or abuffersrc filter with the provided parameters.
* This function may be called multiple times, the later calls override the
* previous ones. Some of the parameters may also be set through AVOptions, then
* whatever method is used last takes precedence.
*
* @param ctx an instance of the buffersrc or abuffersrc filter
* @param param the stream parameters. The frames later passed to this filter
* must conform to those parameters. All the allocated fields in
* param remain owned by the caller, libavfilter will make internal
* copies or references when necessary.
* @return 0 on success, a negative AVERROR code on failure.
*/
int av_buffersrc_parameters_set(AVFilterContext *ctx, AVBufferSrcParameters *param);
/**
* Add a frame to the buffer source.
*
* @param ctx an instance of the buffersrc filter
* @param frame frame to be added. If the frame is reference counted, this
* function will make a new reference to it. Otherwise the frame data will be
* copied.
*
* @return 0 on success, a negative AVERROR on error
*/
int av_buffersrc_write_frame(AVFilterContext *ctx, const AVFrame *frame);
/**
* Add a frame to the buffer source.
*
* @param ctx an instance of the buffersrc filter
* @param frame frame to be added. If the frame is reference counted, this
* function will take ownership of the reference(s) and reset the frame.
* Otherwise the frame data will be copied. If this function returns an error,
* the input frame is not touched.
*
* @return 0 on success, a negative AVERROR on error.
*
* @note the difference between this function and av_buffersrc_write_frame() is
* that av_buffersrc_write_frame() creates a new reference to the input frame,
* while this function takes ownership of the reference passed to it.
*/
int av_buffersrc_add_frame(AVFilterContext *ctx, AVFrame *frame);
/**
* @}
*/
#endif /* AVFILTER_BUFFERSRC_H */