[mythtv-users] HD-PVR giving up

John P Poet jppoet at gmail.com
Tue Nov 3 20:57:29 UTC 2009

On Tue, Nov 3, 2009 at 1:21 PM, Kenneth Emerson
<kenneth.emerson at gmail.com> wrote:
>> ...sounds like a frontend that doesn't have enough horsepower to play back
>> the recording in question. I got a similar result when I tried to play
>> back
>> a 720p HDPVR recording on an AppleTV.
>> [deletia]
>>   Depending on your frontend gear, you might want to lock your cable box
>> into a lower resolution. I had mine at 480p to accomodate my slower
>> frontends like the AppleTV.
> Jedidiah:
> Thanks for your feedback.  I'm running a Q6600, 2.4Ghz quad core, so I don't
> think this is a CPU issue.  My OTA recordings at 1080i are rendered fine
> without using VDPAU.

A 2.4GHz CPU is *not* near powerful enough to render HD-PVR recording
via software.  If you are using VDPAU it is enough, but if you want to
do it in software you need something like a 3GHz Core 2.

HD-PVRs produce single-sliced H.264 which is very difficult to decode.
 OTA (in the US) is done with MPEG2, which is very easy to decode.

> I believe that the problem is actually in the
> recording itself, not in the playback.  I transferred a small piece of the
> video to a Windows laptop and played it with vlc with the same results.  I
> haven't played with any of the bitrates available through the v4l-ctl
> utility.  This may have some impact on the output.  I'll try to play with
> this later.

If you want to decode high bitrate HD-PVR in software, you need a much
more powerful mythfrontend computer.

A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?

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