--- a/video.rst	Tue Aug 07 11:52:26 2012 +0300
+++ b/video.rst	Tue Aug 07 14:18:56 2012 +0300
@@ -13,6 +13,19 @@
   $ sudo apt-get install vlc
   $ sudo apt-get install mplayer
 
+Determine video format.
+=======================
+::
+
+  $ file $VIDEO
+  $ mplayer -frames 0 -vo null -ao null -identify $VIDEO
+  $ mediainfo $VIDEO
+
+See:
+
+  http://en.gentoo-wiki.com/wiki/Show_Video_Codecs
+                Show Video Codecs
+
 3d film.
 ========
 ::