/*
* 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 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
* @{
*/
enum {
/**
* Do not check for format changes.
*/
AV_BUFFERSRC_FLAG_NO_CHECK_FORMAT = 1,
/**
* Immediately push the frame to the output.
*/
AV_BUFFERSRC_FLAG_PUSH = 4,
/**
* Keep a reference to the frame.
* If the frame if reference-counted, create a new reference; otherwise
* copy the frame data.
*/
AV_BUFFERSRC_FLAG_KEEP_REF = 8,
};
/**
* Get the number of failed requests.
*
* A failed request is when the request_frame method is called while no
* frame is present in the buffer.
* The number is reset when a frame is added.
*/
unsigned av_buffersrc_get_nb_failed_requests(AVFilterContext *buffer_src);
/**
* 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 second.
*/
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
*
* This function is equivalent to av_buffersrc_add_frame_flags() with the
* AV_BUFFERSRC_FLAG_KEEP_REF flag.
*/
av_warn_unused_result
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.
*
* This function is equivalent to av_buffersrc_add_frame_flags() without the
* AV_BUFFERSRC_FLAG_KEEP_REF flag.
*/
av_warn_unused_result
int av_buffersrc_add_frame(AVFilterContext *ctx, AVFrame *frame);
/**
* Add a frame to the buffer source.
*
* By default, if the frame is reference-counted, this function will take
* ownership of the reference(s) and reset the frame. This can be controlled
* using the flags.
*
* If this function returns an error, the input frame is not touched.
*
* @param buffer_src pointer to a buffer source context
* @param frame a frame, or NULL to mark EOF
* @param flags a combination of AV_BUFFERSRC_FLAG_*
* @return >= 0 in case of success, a negative AVERROR code
* in case of failure
*/
av_warn_unused_result
int av_buffersrc_add_frame_flags(AVFilterContext *buffer_src,
AVFrame *frame, int flags);
/**
* Close the buffer source after EOF.
*
* This is similar to passing NULL to av_buffersrc_add_frame_flags()
* except it takes the timestamp of the EOF, i.e. the timestamp of the end
* of the last frame.
*/
int av_buffersrc_close(AVFilterContext *ctx, int64_t pts, unsigned flags);
/**
* @}
*/
#endif /* AVFILTER_BUFFERSRC_H */