Buffer video frames, and make them available to the filter chain.

This source is mainly intended for a programmatic use, in particular through the interface defined in libavfilter/vsrc_buffer.h.

It accepts a list of options in the form of key=value pairs separated by ":". A description of the accepted options follows.

video_size

Specify the size (width and height) of the buffered video frames.

pix_fmt

A string representing the pixel format of the buffered video frames. It may be a number corresponding to a pixel format, or a pixel format name.

time_base

Specify the timebase assumed by the timestamps of the buffered frames.

time_base

Specify the frame rate expected for the video stream.

pixel_aspect

Specify the sample aspect ratio assumed by the video frames.

sws_param

Specify the optional parameters to be used for the scale filter which is automatically inserted when an input change is detected in the input size or format.

For example:

buffer=size=320x240:pix_fmt=yuv410p:time_base=1/24:pixel_aspect=1/1

will instruct the source to accept video frames with size 320x240 and with format "yuv410p", assuming 1/24 as the timestamps timebase and square pixels (1:1 sample aspect ratio). Since the pixel format with name "yuv410p" corresponds to the number 6 (check the enum AVPixelFormat definition in libavutil/pixfmt.h), this example corresponds to:

buffer=size=320x240:pixfmt=6:time_base=1/24:pixel_aspect=1/1

Alternatively, the options can be specified as a flat string, but this syntax is deprecated:

width:height:pix_fmt:time_base.num:time_base.den:pixel_aspect.num:pixel_aspect.den[:sws_param]