[mythtv-users] 720p harder to decode than 1080i?

[Steven Adeff]

On 11/20/06, Mark Chang <mark.chang at gmail.com> wrote:
> I am assuming 720p is harder to decode than 1080i? I ask because it
> turns out that my recently-built HDTV Myth box doesn't have enough
> horsepower to play back some OTA recorded streams.
>
> In particular, CBS seems to broadcast in a higher resolution than
> other channels. The 1 hour recording of "NUMB3RS" takes 7+GB, while
> the same length of "Desperate Housewives" takes only like 5GB. Am I
> assuming right that different channels broadcast at different rates?
>
> Anyways, I tried introducing XvMC (Ubuntu Edgy + nvidia), but it
> really only made things worse. Anyone get XvMC working in this
> configuration (above + AMD64)? How do I verify that XvMC is "on"?
>
> Thanks.

while they do broadcast at different rates, what your seeing is the
file size difference between 1080i and 720p. CBS is 1080i, ABC is
720p.

1080i is "harder" to decode than 720p as it requires more processing
for its larger frame size, 1920x1080 vs 1280x720.

XvMC should work. A little more information on your problem can help
identify the issue. To see if its on check your mythfrontend log "-v
playback" should enable the video output logging info iirc.

-- 
Steve
Before you ask, read the FAQ!
http://www.mythtv.org/wiki/index.php/Frequently_Asked_Questions
then search the Wiki, and this list,
http://www.gossamer-threads.com/lists/mythtv/
Mailinglist etiquette -
http://www.mythtv.org/wiki/index.php/Mailing_List_etiquette