[FFmpeg-devel] [PATCH] avfilter/vf_drawtext: document expr for fontsize

[Andrei Rybak]

Expressions for parameter fontsize of video filter drawtext have been
supported since commit 6442e4ab3c (avfilter/vf_drawtext: added expr
evaluation to drawtext fontsize, 2017-04-18).

Add an example of using such expressions to documentation.

Signed-off-by: Andrei Rybak <rybak.a.v at gmail.com>
---
 doc/filters.texi | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/doc/filters.texi b/doc/filters.texi
index fb8757ff8f..ec386a6c55 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -10233,6 +10233,12 @@ Use fontconfig to set the font. Note that the colons need to be escaped.
 drawtext='fontfile=Linux Libertine O-40\:style=Semibold:text=FFmpeg'
 @end example
 
+ at item
+Draw "Test Text" of size, dependent on height of the video.
+ at example
+drawtext="text='Test Text': fontsize=h/30: x=(w-text_w)/2: y=(h-text_h*2)"
+ at end example
+
 @item
 Print the date of a real-time encoding (see strftime(3)):
 @example
-- 
2.25.1