/*

  * 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 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

  *
  * 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 */