[mythtv-users] Pointers for MythTV frontend on Koolu?

[Michael T. Dean]

On 02/09/2008 06:11 PM, Ted Roche wrote:
> On Feb 9, 2008 4:29 PM, Brian Wood <beww at beww.org> wrote:
>   
>> Actually if top is showing you 95% CPU usage I'd guess that is your
>> problem. MPEG4 decoding takes much more CPU than MPEG2, assuming no
>> hardware help.
> No, this is a low-power computer (9 watts!) , and I haven't tried
> transcoding yet. The videos on the mythtv backend report that they are
> MPEG-2 when I query them with mplayer.
>
> I suspect the clue about transcoding to mpeg4 is legit; the
> motherboard has the AMD Geode chipset onboard which supposedly has
> hardware decode. And the koolu.org site is emphatic that you have to
> download the AMD driver set to get MythTV to work, which I have done.

Actually, there are multiple "profiles" for MPEG-4--including MPEG-4 
Part 2 (generally what people think of as "plain" MPEG-4) and MPEG-4 AVC 
(a.k.a. H.264 a.k.a. MPEG-4 Part 10).  For example, MPEG-4 Part 2 has 
Simple Profile and Advanced Simple Profile (which is very similar to 
H.263).  Similarly, MPEG-4 AVC has a Baseline Profile for lower-cost 
applications with limited computing resources.  It's designed 
specifically for resource-constrained, low-power, and/or low-bandwidth 
devices (such as video conferencing or mobile applications).

I haven't seen any decoding performance comparisons against, i.e. 
MPEG-2, but I'd guess the simplest MPEG-4 profiles are not significantly 
more resource intensive than "normal" MPEG-2 (which, BTW, also has 
several profiles... ;)

Mike