[mythtv] [mythtv-commits] Ticket #3035: 1080i source material playback results in solid blue video with Via-XvMC

Brian Teague teague at wisc.edu
Wed Feb 7 19:39:28 UTC 2007

On Tue, 2007-02-06 at 20:05 -0800, Paul Bender wrote:
> >> I think i readed somewhere the unichrome chipset only supports up
> to 
> >> 1024x1024. Perhaps thats the problem?

For the original Unichrome, this is true.  However, the Epia SP
motherboards sport the newer Unichrome Pro chipsets, which can decode a
1080i stream.  Unfortunately, the video chipset is shared memory, and
even the maximum setting (64 Mb) is not enough VRAM to allocate 16
decoding buffers.  I've attached a patch to ticket #3035 that changes
the value to 14 buffers, which allows playback of 1080i content.

I'm running it on an Epia SP800, which can just barely handle HD
playback.  There are a few other tweaks I made (buffering, real-time
priority for the decoding thread) that help matters immensely.  However,
I havn't had time to test those changes in the mythtv-vid branch (as I
was asked to do the last time I posted the patch, on ticket #1842).
When I have time to do so, I'll post the full patchset there and on


Brian Teague
teague at wisc.edu
The Laboratory for Molecular and Computational Genomics

If in any problem you find yourself doing an immense amount of work, the
answer can be obtained by simple inspection.

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