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/*
* 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_BUFFERSINK_H
#define AVFILTER_BUFFERSINK_H
/**
* @file
* @ingroup lavfi_buffersink
* memory buffer sink API for audio and video
*/
#include "avfilter.h"
/**
* @defgroup lavfi_buffersink Buffer sink API
* @ingroup lavfi
* @{
*
* The buffersink and abuffersink filters are there to connect filter graphs
* to applications. They have a single input, connected to the graph, and no
* output. Frames must be extracted using av_buffersink_get_frame() or
* av_buffersink_get_samples().
*
* The format negotiated by the graph during configuration can be obtained
* using the accessor functions:
* - av_buffersink_get_time_base(),
* - av_buffersink_get_format(),
* - av_buffersink_get_frame_rate(),
* - av_buffersink_get_w(),
* - av_buffersink_get_h(),
* - av_buffersink_get_sample_aspect_ratio(),
* - av_buffersink_get_channels(),
* - av_buffersink_get_ch_layout(),
* - av_buffersink_get_sample_rate().
*
* The layout returned by av_buffersink_get_ch_layout() must de uninitialized
* by the caller.
*
* The format can be constrained by setting options, using av_opt_set() and
* related functions with the AV_OPT_SEARCH_CHILDREN flag.
* - pixel_formats (array of pixel formats),
* - colorspaces (array of int),
* - colorranges (array of int),
* - sample_formats (array of sample formats),
* - samplerates (array of int),
* - channel_layouts (array of channel layouts)
* If an option is not set, all corresponding formats are accepted.
*/
/**
* Get a frame with filtered data from sink and put it in frame.
*
* @param ctx pointer to a buffersink or abuffersink filter context.
* @param frame pointer to an allocated frame that will be filled with data.
* The data must be freed using av_frame_unref() / av_frame_free()
* @param flags a combination of AV_BUFFERSINK_FLAG_* flags
*
* @return >= 0 in for success, a negative AVERROR code for failure.
*/
int av_buffersink_get_frame_flags(AVFilterContext *ctx, AVFrame *frame, int flags);
/**
* Tell av_buffersink_get_buffer_ref() to read video/samples buffer
* reference, but not remove it from the buffer. This is useful if you
* need only to read a video/samples buffer, without to fetch it.
*/
#define AV_BUFFERSINK_FLAG_PEEK 1
/**
* Tell av_buffersink_get_buffer_ref() not to request a frame from its input.
* If a frame is already buffered, it is read (and removed from the buffer),
* but if no frame is present, return AVERROR(EAGAIN).
*/
#define AV_BUFFERSINK_FLAG_NO_REQUEST 2
/**
* Set the frame size for an audio buffer sink.
*
* All calls to av_buffersink_get_buffer_ref will return a buffer with
* exactly the specified number of samples, or AVERROR(EAGAIN) if there is
* not enough. The last buffer at EOF will be padded with 0.
*/
void av_buffersink_set_frame_size(AVFilterContext *ctx, unsigned frame_size);
/**
* @defgroup lavfi_buffersink_accessors Buffer sink accessors
* Get the properties of the stream
* @{
*/
enum AVMediaType av_buffersink_get_type (const AVFilterContext *ctx);
AVRational av_buffersink_get_time_base (const AVFilterContext *ctx);
int av_buffersink_get_format (const AVFilterContext *ctx);
AVRational av_buffersink_get_frame_rate (const AVFilterContext *ctx);
int av_buffersink_get_w (const AVFilterContext *ctx);
int av_buffersink_get_h (const AVFilterContext *ctx);
AVRational av_buffersink_get_sample_aspect_ratio (const AVFilterContext *ctx);
enum AVColorSpace av_buffersink_get_colorspace (const AVFilterContext *ctx);
enum AVColorRange av_buffersink_get_color_range (const AVFilterContext *ctx);
int av_buffersink_get_channels (const AVFilterContext *ctx);
int av_buffersink_get_ch_layout (const AVFilterContext *ctx,
AVChannelLayout *ch_layout);
int av_buffersink_get_sample_rate (const AVFilterContext *ctx);
AVBufferRef * av_buffersink_get_hw_frames_ctx (const AVFilterContext *ctx);
/** @} */
/**
* Get a frame with filtered data from sink and put it in frame.
*
* @param ctx pointer to a context of a buffersink or abuffersink AVFilter.
* @param frame pointer to an allocated frame that will be filled with data.
* The data must be freed using av_frame_unref() / av_frame_free()
*
* @return
* - >= 0 if a frame was successfully returned.
* - AVERROR(EAGAIN) if no frames are available at this point; more
* input frames must be added to the filtergraph to get more output.
* - AVERROR_EOF if there will be no more output frames on this sink.
* - A different negative AVERROR code in other failure cases.
*/
int av_buffersink_get_frame(AVFilterContext *ctx, AVFrame *frame);
/**
* Same as av_buffersink_get_frame(), but with the ability to specify the number
* of samples read. This function is less efficient than
* av_buffersink_get_frame(), because it copies the data around.
*
* @param ctx pointer to a context of the abuffersink AVFilter.
* @param frame pointer to an allocated frame that will be filled with data.
* The data must be freed using av_frame_unref() / av_frame_free()
* frame will contain exactly nb_samples audio samples, except at
* the end of stream, when it can contain less than nb_samples.
*
* @return The return codes have the same meaning as for
* av_buffersink_get_frame().
*
* @warning do not mix this function with av_buffersink_get_frame(). Use only one or
* the other with a single sink, not both.
*/
int av_buffersink_get_samples(AVFilterContext *ctx, AVFrame *frame, int nb_samples);
/**
* @}
*/
#endif /* AVFILTER_BUFFERSINK_H */
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