[FFmpeg-devel] [PATCH] drawbox: Respect thickness parameter

Andrey Utkin andrey.krieger.utkin at gmail.com
Thu Jun 13 16:40:14 CEST 2013

2013/6/12 Jean Delvare <khali at linux-fr.org>:
> The drawbox video filter is drawing lines one pixel thinner than
> requested. The default thickness is 4 pixel but in fact the lines
> drawn by default are only 3 pixel wide.
> Change the comparisons in the code to fix this off-by-one bug. Also
> change the default thickness from 4 to 3 to minimize the unexpected
> changes from the user's perspective.

Interpreted ffmpeg code on the paper with pencil, original bug is
reproduced, and the patch fixes it.

> As I was already touching these lines, I also removed the "maximum" in
> the thickness parameter description, as I don't think it was adding
> any value and I even found it confusing.

This could be considered a feature :) the thickness really does not
exceed "maximum" value given by user :)
I agree with changing the description line.

Andrey Utkin

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