[mythtv-users] 1080 content scaling problems

[Michael T. Dean]

On 05/28/2008 09:35 PM, EJS wrote:
> --- EJS <ejshoor at yahoo.com> wrote:
>> --- "Michael T. Dean" wrote:
>>> video driver bug
>> Hey thanks. At least thats something to look at. I
>> will take a look at other driver versions; and
>> perhaps
>> see what the content looks like in mplayer.
>> At least I know Im not missing something in my X
>> configuration.
> Well I just tried driver version 173.14.05 (just
> released today) and same behavior. I also tried
> mplayer and saw the following in the logs:
>   
...
> The selected video_out device is incompatible with
> this codec.
> Try appending the scale filter to your filter list,
> e.g. -vf spp,scale instead of -vf spp.
...
> Does this confirm its a bug in the driver?

What that message says is that your video card is unable to scale the 
image from 1920x1080 to the resolution you're using (1024x768, IIRC).  
Therefore, it's suggesting a workaround of using a software scaler.

>   Just out
> of curiousity, would you happen to know what the "bug"
> is related to?

The video driver vendor (or, perhaps the GPU designer) simply assumes 
that anyone trying to play back HDTV will use some minimum resolution 
and doesn't want to implement the functionality required to down-scale 
to lower resolutions.

>  Is it related to using the composite
> out on the card?

Nope.  Only related to trying to play back 1920x1080 on a much-lower 
resolution output.  Therefore, if you were to configure X for 1920x1080, 
all would work well (probably even 1280x720--or, for a 4:3 display, 
1280x960--would be fine).  However, I know that there's a maximum 
resolution that can be used with composite out, so if the min downscale 
resolution is greater than the max composite resolution, ...

>  Could I assume a newer TV would
> resolve the problem?

Yes.  One with a higher resolution (such as a nice new HDTV).  :)  
(Technically, though, it would simply allow you to avoid the problem by 
outputting an image that doesn't need downscaled so drastically.)

Mike