
The stream sent to the second output of split, labelled as, is processed through the crop filter, which crops away the lower half part of the video, and then vertically flipped. In the example, the split filter generates two outputs that are associated to the labels and. The points where the linear chains join are labelled by names enclosed in square brackets. In our example, crop,vflip are in one linear chain, split and overlay are separately in another. The result will be that the top half of the video is mirrored onto the bottom half of the output video.įilters in the same linear chain are separated by commas, and distinct linear chains of filters are separated by semicolons. You can use the following command to achieve this: ffmpeg -i INPUT -vf "split crop=iw:ih/2:0:0, vflip overlay=0:H/2" OUTPUT This filtergraph splits the input stream in two streams, then sends one stream through the crop filter and the vflip filter, before merging it back with the other stream by overlaying it on top. To illustrate the sorts of things that are possible, we consider the following filtergraph. In libavfilter, a filter can have multiple inputs and multiple outputs. Filtering Introductionįiltering in FFmpeg is enabled through the libavfilter library. This document describes filters, sources, and sinks provided by the libavfilter library. allrgb, allyuv, color, colorchart, colorspectrum, haldclutsrc, nullsrc, pal75bars, pal100bars, rgbtestsrc, smptebars, smptehdbars, testsrc, testsrc2, yuvtestsrc.Options for Filters with Several Inputs.Changing Options at Runtime with a Command.
