avfilter: add identity video filter

[ffmpeg] / doc / filters.texi

diff --git a/doc/filters.texi b/doc/filters.texi
index 426cb158da1126bf75d4032f76e18b9ea9c0420c..38698b6542a5e5843eb556fd0dd178f3a978c117 100644 (file)
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -13382,6 +13382,28 @@ By default value is 0.
 
 The @code{hysteresis} filter also supports the @ref{framesync} options.
 
+@section identity
+
+Obtain the identity score between two input videos.
+
+This filter takes two input videos.
+
+Both input videos must have the same resolution and pixel format for
+this filter to work correctly. Also it assumes that both inputs
+have the same number of frames, which are compared one by one.
+
+The obtained per component, average, min and max identity score is printed through
+the logging system.
+
+The filter stores the calculated identity scores of each frame in frame metadata.
+
+In the below example the input file @file{main.mpg} being processed is compared
+with the reference file @file{ref.mpg}.
+
+@example
+ffmpeg -i main.mpg -i ref.mpg -lavfi identity -f null -
+@end example
+
 @section idet
 
 Detect video interlacing type.