/* * 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     */    AVChannelLayout ch_layout;     /**     * Video only, the YUV colorspace and range.     */    enum AVColorSpace color_space;    enum AVColorRange color_range;     AVFrameSideData **side_data;    int nb_side_data;} 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_resultint 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_resultint 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_resultint 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 */