Bug#765969: [vlc] green line under some Mpeg-4 XVID videos

[Rémi Denis-Courmont]

tags 765969 + wontfix
thanks

Le vendredi 07 novembre 2014, 23:35:41 Dirk Griesbach a écrit :
> Am Fr, 07. Nov 2014 um 23:17:12 +0100 schrieb Francesco Muzio:
> > what driver/graphics card are you using?
> 
> VGA-compatible devices on PCI bus:
> 00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile
> 945GM/GMS, 943/940GML Express Integrated Graphics Controller [8086:27a2]
> (rev 03)

Probably more than one driver is affected. But I did spend several hours 
troubleshooting it on an affected system and so far it does seem like a driver 
bug: the driver is blending the last line of visible pixels with the first line 
of pixels outside the visible area. All zeroes corresponds to dark green in 
YUV colours space.

Now, I´m not flawless, but with no further arguments, I consider this a driver 
bug. Considering how bad of a reputation XVideo has accumulated with GPU 
driver developers, this is not even surprising.

VLC 3.0 is intended to switch to default to OpenGL (GLX) rather than XVideo. 
Debian might consider doing the same in their VLC package. This should work 
around the bug and would also improve scaling of subpictures. But of course, 
it would expose other potential GPU driver bugs.

-- 
Rémi Denis-Courmont
http://www.remlab.net/