[FFmpeg-cvslog] doc/filters: update astats description

[Paul B Mahol]

ffmpeg | branch: master | Paul B Mahol <onemda at gmail.com> | Mon Sep 17 12:34:57 2018 +0200| [e9ef583f997c1c5ea0d41d6c5b81e6c93e6bbe2a] | committer: Paul B Mahol

doc/filters: update astats description

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e9ef583f997c1c5ea0d41d6c5b81e6c93e6bbe2a
---

 doc/filters.texi | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/doc/filters.texi b/doc/filters.texi
index 5cc96bc1cc..e8f0aae8dc 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -1932,6 +1932,8 @@ Flat_factor
 Peak_count
 Bit_depth
 Dynamic_range
+Zero_crossings
+Zero_crossings_rate
 
 and for Overall:
 DC_offset
@@ -2009,6 +2011,12 @@ Overall bit depth of audio. Number of bits used for each sample.
 
 @item Dynamic range
 Measured dynamic range of audio in dB.
+
+ at item Zero crossings
+Number of points where the waveform crosses the zero level axis.
+
+ at item Zero crossings rate
+Rate of Zero crossings and number of audio samples.
 @end table
 
 @section atempo