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diff --git a/doc/libavfilter.texi b/doc/libavfilter.texi deleted file mode 100644 index b452294a5f..0000000000 --- a/doc/libavfilter.texi +++ /dev/null @@ -1,92 +0,0 @@ -\input texinfo @c -*- texinfo -*- - -@settitle Libavfilter Documentation -@titlepage -@center @titlefont{Libavfilter Documentation} -@end titlepage - -@top - -@contents - -@chapter Introduction - -Libavfilter is the filtering API of Libav. It is the substitute of the -now deprecated 'vhooks' and started as a Google Summer of Code project. - -But note that there may still be serious bugs in the code and its API -and ABI should not be considered stable yet! - -@chapter Tutorial - -In libavfilter, it is possible for filters to have multiple inputs and -multiple outputs. -To illustrate the sorts of things that are possible, we can -use a complex filter graph. For example, the following one: - -@example -input --> split --> fifo -----------------------> overlay --> output - | ^ - | | - +------> fifo --> crop --> vflip --------+ -@end example - -splits the stream in two streams, sends one stream through the crop filter -and the vflip filter before merging it back with the other stream by -overlaying it on top. You can use the following command to achieve this: - -@example -./avconv -i input -vf "[in] split [T1], fifo, [T2] overlay=0:H/2 [out]; [T1] fifo, crop=iw:ih/2:0:ih/2, vflip [T2]" output -@end example - -The result will be that in output the top half of the video is mirrored -onto the bottom half. - -Video filters are loaded using the @var{-vf} option passed to -avconv or to avplay. Filters in the same linear chain are separated by -commas. In our example, @var{split, fifo, overlay} are in one linear -chain, and @var{fifo, crop, vflip} are in another. The points where -the linear chains join are labeled by names enclosed in square -brackets. In our example, that is @var{[T1]} and @var{[T2]}. The magic -labels @var{[in]} and @var{[out]} are the points where video is input -and output. - -Some filters take in input a list of parameters: they are specified -after the filter name and an equal sign, and are separated each other -by a semicolon. - -There exist so-called @var{source filters} that do not have a video -input, and we expect in the future some @var{sink filters} that will -not have video output. - -@chapter graph2dot - -The @file{graph2dot} program included in the Libav @file{tools} -directory can be used to parse a filter graph description and issue a -corresponding textual representation in the dot language. - -Invoke the command: -@example -graph2dot -h -@end example - -to see how to use @file{graph2dot}. - -You can then pass the dot description to the @file{dot} program (from -the graphviz suite of programs) and obtain a graphical representation -of the filter graph. - -For example the sequence of commands: -@example -echo @var{GRAPH_DESCRIPTION} | \ -tools/graph2dot -o graph.tmp && \ -dot -Tpng graph.tmp -o graph.png && \ -display graph.png -@end example - -can be used to create and display an image representing the graph -described by the @var{GRAPH_DESCRIPTION} string. - -@include filters.texi - -@bye |