[mythtv-users] HDTV on EPIA SP13000

[R. G. Newbury]

Pavol Droba wrote:
> On Tue, Jun 13, 2006 at 03:24:15PM -0400, R. G. Newbury wrote:
>> James D wrote:
>>> Has anyone actually got this to work well?
>>> I've read this post to the dev list: 
>>> http://mythtv.org/pipermail/mythtv-dev/2005-December/042588.html
>>> but I can't even get close to the results he claims.
>>>  
>>> With Via XvMC selected I can actually watch HDTV without the CPU being 
>>> the bottleneck, but some channels / programs it will be very close. CPU 
>>> usage is usally 70% - 95% watching HD content depending on the format 
>>> and program. The video is smooth enough, but the audio is choppy no 
>>> matter what I do. Enabling AC3 passthrough makes it much worse... any ideas?
>>>  
>>> The other thing is the video only works on 720p and SD channels, 1080 
>>> channels just show a blank screen with audio (that isn't choppy 
>>> ironically). Perhaps I need to make the code adjustment from the post 
>>> above? I'm hesitant since I rather rely on gentoo than do a hand 
>>> compile, but you can only set the framebuffer memory to 64M max in the 
>>> BIOS, so I'm suspicous there isn't enough video memory for 1080. I've 
>>> set the framebuffer to 64M, I've got 512M in the box... I wonder if the 
>>> bus could be the bottleneck??
>>>  
>>> Would appreciate if anyone who has watchable HD on an EPIA would share 
>>> what they did.
>>
>> You DO realize that the chipset on the SP13000 will NOT actually do full 
>> HD? The limit is 1024x1024 apparently to VGA and something less through 
>> the S-video output (limitation of S-video??)
> 
> 
> This information is not correct. The limit applies to Unichrome (non pro) chipsets.
> SP13000 have UnichromePro chipset and should be able to decode HD.
> 
> However, it cannot realy play it right now on MythTV as far as I know.
> There was a discussion on the openchrome list. Apparently mythtv tries to allocate
> more frames beforehand than could actualy be sqeezed into the graphic
> card's memory.
> 
> The HD playback will not be functional over TV-out, since it is not HD ready,
> you will have to use VGA port.
> 
> Regards,
> Pavol

Sorry Pavol, but the limit is 1024x768 for the VT1623 chipset (and 
probably less for the VT1622. You have to dig around on the various VIA 
sites, and search on VT1623 to find relevant information. I cannot 
remember or find exactly which pdf or page where I found that 
information. And I cannot find it right now. It was on the via-embedded 
site I think. Via actually keep this information very well hidden, 
although they boast about the chipset having 'TV -out' capabilities they 
will not give specifications or limits.

Moreover, on the SP series you are probably going to be limited by the 
S-video in terms of what HD you can push to the TV, so the limits of the 
  TV-out chipset are irrelevant. I CAN watch HD level content on my 
monitor, with the SP13000, but my monitor is, of course, connected to 
the VGA output and the display monitor (a Phillips 21") will do better 
than 1908x1080 itself.

They are slightly more forthcoming with the VT1625 chipset which is in 
the new EN boards (and one of the nano boards IIRC). That chipset will 
do the full 1980x1080i. They are proud of that!

Geoff