Bug#670236: mplayer2: can't play video with resolution of 2542x1080

[Roland Scheidegger]

Am 06.05.2012 23:53, schrieb Rogério Brito:
> Hi, Uoti.
> 
> On Apr 26 2012, Uoti Urpala wrote:
>> This is a limitation reported by libXv. It's likely due to limitations
>> of your graphics hardware. You can try other output methods such as gl,
>> but it's likely they won't work well either on such hardware.
> 
> Yes, I just went to read the code and I came to the conclusion that it was
> some limitation reported by Xv and I, then, sent an e-mail to the xorg
> mailing list:
> 
>     http://lists.x.org/archives/xorg/2012-April/054484.html
> 
> (I'm including the xorg list here in CC).
> 
> As Alex Deucher said there, it is a little bit strange that even a Sandy
> Bridge notebook has this limitation of playing only 2kx2k videos (which is
> the same that my 865 has).
> 
> Just curious: what hardware do you use?
> 
>> Using --xy=0.5 won't help, because that will try to do the scaling in
>> hardware, but the limitation is about hardware input image size. You can
>> force software scaling on CPU with options like "--vf=scale=1920:-2".
>> This would add a filter to do software scaling to a width of 1920 and a
>> height that keeps the original aspect ratio, which should fit within the
>> limitations of your hardware. You may want to adjust the value of 1920
>> if you have a monitor smaller or larger than that.
> 
> OK, that's a reasonable workaround for the moment.
> 
> I guess that this bug may be reassigned, then, but I'm not sure if that
> should be to xserver-xorg-video-intel or any other package.
> 
> In the mean time, it would be nice to hear from the Intel people working
> with X (perhaps Keith Packard?) if those limitations are there just for
> being hardcoded or if the hardware has that limitation itself.
> 

The intel driver is just using ordinary textures for xv as far as I can
tell. So, unless the hardware requires some specific setup for textures
larger than 2048, it should just work with larger sizes. The hw limit
for any DX10-capable hardware is at least 8192, so even a i965 chipset
should handle that.
You could try it out by compiling the intel ddx driver yourself, the
limits are IMAGE_MAX_WIDTH/IMAGE_MAX_HEIGHT in intel_video.c.
(Of course, the real fix would take the hw into account, 2048 seems
indeed like the limit for i915.)

Roland