From 5282cbae61ccf75dbfbeac5b963812aac90ec8cb Mon Sep 17 00:00:00 2001 From: Gyan Doshi Date: Sat, 30 Mar 2019 12:07:24 +0530 Subject: [PATCH] doc/filters: mention input requirements for ebur128 The filter requires input stream to have sample rate 48000 Hz and dbl fmt. Fixes #7812 --- doc/filters.texi | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/doc/filters.texi b/doc/filters.texi index cf13a587ba..867607d870 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -20587,11 +20587,16 @@ ebur128=metadata=1,adrawgraph=lavfi.r128.M:min=-120:max=5 @anchor{ebur128} @section ebur128 -EBU R128 scanner filter. This filter takes an audio stream as input and outputs -it unchanged. By default, it logs a message at a frequency of 10Hz with the +EBU R128 scanner filter. This filter takes an audio stream and analyzes its loudness +level. By default, it logs a message at a frequency of 10Hz with the Momentary loudness (identified by @code{M}), Short-term loudness (@code{S}), Integrated loudness (@code{I}) and Loudness Range (@code{LRA}). +The filter can only analyze streams which have a sampling rate of 48000 Hz and whose +sample format is double-precision floating point. The input stream will be converted to +this specification, if needed. Users may need to insert aformat and/or aresample filters +after this filter to obtain the original parameters. + The filter also has a video output (see the @var{video} option) with a real time graph to observe the loudness evolution. The graphic contains the logged message mentioned above, so it is not printed anymore when this option is set,