From 5c1330798978cee5b4d7926bea611820b1019804 Mon Sep 17 00:00:00 2001 From: Stefano Sabatini Date: Sun, 26 Mar 2023 19:32:17 +0200 Subject: [PATCH] doc/filters: mentions that whitespaces are ignored in the filtergraph specification Also provide example showing how to use this feature to improve filtergraph readability. Address issue: http://trac.ffmpeg.org/ticket/8115 --- doc/filters.texi | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/doc/filters.texi b/doc/filters.texi index 1c9d523340..889de8b11a 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -214,6 +214,23 @@ In a complete filterchain all the unlabelled filter input and output pads must be connected. A filtergraph is considered valid if all the filter input and output pads of all the filterchains are connected. +Leading and trailing whitespaces (space, tabs, or line feeds) separating tokens +in the filtergraph specification are ignored. This means that the filtergraph +can be expressed using empty lines and spaces to improve redability. + +For example, the filtergraph: +@example +testsrc,split[L1],hflip[L2];[L1][L2] hstack +@end example + +can be represented as: +@example +testsrc, +split [L1], hflip [L2]; + +[L1][L2] hstack +@end example + Libavfilter will automatically insert @ref{scale} filters where format conversion is required. It is possible to specify swscale flags for those automatically inserted scalers by prepending