png: Calculate pixel format information only once

[ffmpeg] / doc / fftools-common-opts.texi

diff --git a/doc/fftools-common-opts.texi b/doc/fftools-common-opts.texi
index 655690956acd051f0df7c0305850a505038925fa..2e7c9f7e8fb212f49dcc29e600ac98dda61f14e2 100644 (file)
--- a/doc/fftools-common-opts.texi
+++ b/doc/fftools-common-opts.texi
@@ -50,6 +50,9 @@ Match the stream by stream id (e.g. PID in MPEG-TS container).
 Matches streams with the metadata tag @var{key} having the specified value. If
 @var{value} is not given, matches streams that contain the given tag with any
 value.
+@item u
+Matches streams with usable configuration, the codec must be defined and the
+essential information such as video dimension or audio sample rate must be present.
 
 Note that in @command{ffmpeg}, matching by metadata will only work properly for
 input files.