[MPlayer-users] bmovl usage and transparent mode

[adrien.bosc at bertin.fr]

Hi,

I am trying to display an overlay using bmovl function of mplayer.

Everything is well displayed when the option is configured to opaque (
bmovl=0:1), but not working correctly when in alphablending (transparent) 
mode (bmovl=0:0)

When in transparent mode, only pixels with alpha at 256 are displayed and, 
for example, when I draw a rectangle, I can see a non linear offset on 
each line. It is also only black and white.

Again, with the opaque option, everything is well displayed

I am running mplayer like this:

execlp("xterm", "xterm", "-e", "mplayer", "-demuxer", "h264es", "-fs", 
"/tmp/fifo_mplayer", "-vf", "bmovl=0:0:/tmp/fifo_mplayer_overlay", NULL);

I tried this on Ubuntu 16.04 (On a Virtual Machine and on a real one) with 
mplayer 1.2.1 and 1.3.0 and the result is the same.

Any idea about what I can miss?
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