[mythtv-users] CPU usage during Playback of content from HD-PVR
Brad DerManouelian
myth at dermanouelian.com
Wed Aug 13 17:19:05 UTC 2008
On Aug 13, 2008, at 9:38 AM, Robert McNamara wrote:
> Hi Brad,
>
> Apologies, didn't see the first few messages in this topic until you
> pointed me at them, so I got it a little out of context. Up to
> speed now. In fact, thought you were a responder rather than the
> OP. Anyway, what I was getting at was the even *with* CoreAVC, the
> 4400+ may be too slow. CoreAVC will multithread this content,
> indeed, but it will do so much better with the 1080i captures than
> the 720p ones. Reason being, it appears to put the deinterlace in
> one thread, and the decode in another, still limiting decode to a
> single thread (and thus, to a single processor). The 138% you're
> seeing is likely 100% decode on a single processor, and 38%
> deinterlace on a second. That's just a guess based on my experience
> and on helping folks in #hdpvr, but it's been borne out thus far.
>
> The slowest proc I've gotten things working smoothly on w/ CoreAVC
> had been a C2D @ 2.4 Ghz, which is slightly faster clock-for-clock
> than the 4400+. Even then, I see the occasional skip and freeze.
> My experience with it has also been that 1080i plays back much
> better w/ CoreAVC than 720p. If you're on 720, you might give 1080i
> a shot and be pleasantly surprised. If not, you may need just a bit
> more oomph.
>
> For reference, I put the link on the HD-PVR page pointing at the HD
> Playback reports page because I want it fleshed out with more HD-PVR
> information-- it just hasn't gotten there yet. I ought to add my
> own experiences to help others, just haven't gotten around to it.
Thanks! That's very helpful. I will certainly take a look at 1080i
content. I guess it makes sense that 1080i would be easier since there
wouldn't be any scaling on a 1920x1080 display. I can actually play
720p at 100% in mplayer without issue so it's the scaling that's
really killing me. I wish there was a way to automagically change the
res of the display to match the content being played. I might take a
look into that unless someone else has a suggestion about how to do
that. (This needs to be easy enough for my 11 year old to operate, so
switching resolutions manually depending on the content isn't really a
working option.)
More information about the mythtv-users
mailing list