[mythtv-users] Choppy hd live tv playback with HD3000

[Brandon Beattie]

On Mon, Dec 19, 2005 at 03:42:11PM -0800, Mark Johannessen wrote:
> I have been able to install mythtv/mythweb sucessfully (after about a
> weekend of work) on the following box:
> 
> Intel Celeron 2.66 gHz
> 768 ram
> Nvidia e-GeForce MX4000 AGP card
> Soundbalster audio card
> FC4
> 
> The system is hooked up to an HD antenna and the signal is fine,
> channels can be selected, audio from the sound card works, mythweb
> works, etc.  However, when either playing live TV or playing back
> recorded shows, the playback studders.  It plays for a couple of
> seconds, studders, and plays for another couple of seconds, and so
> forth.  The pattern is regular.  I have plenty of HD space, using an
> LVM with jsf format.
> 
> According the pcHDTV site, the HD3000 requires the following:
> 
> The minimum recommended hardware requirements for playback of HDTV
> streams recorded by pcHDTV cards are:
> 
> Intel(r) Pentium(r) 1200Mhz or higher
> NVIDIA card with IDCT acceleration for machines under 2000MHz (Note:
> with the current drivers on the nvidia site downloaded and operating
> it think - I get the nvidia splash screen on boot)
> Sound card (S/Pdif output required for 5.1 audio)
> 256 Meg RAM or higher
> 
> The minimum recommended hardware requirements for recording of HDTV
> streams by pcHDTV cards are:
> Linux Kernel 2.6.12 for DVB driver (Recommended)
> Linux Kernel 2.4.26 for Video4Linux driver (Optional)
> Intel(r) Pentium(r) 400Mhz or higher
> 128 Meg RAM or higher
> One available PCI 2.2 slot
> Hard drive capable of writing 6MB/s
> 
> I seem to have met these requirements, yet I have a choppiness
> problem.  From the spec sheet on the card I don't see IDCT mentioned,
> but it does mention "full OpenGL ICD" support.
> 
> Does this look like a video card issue (even though I appear to have
> the processor speed) or has someone found this problem and a different
> solution?

A 1.2Ghz is fine for playback with mplayer, xine, and so on but Not
Myth.  You can try using libmpeg (See settings->playback->page 1) which
may not use as much cpu for decoding.  FFmpeg that is used for Myth uses
more CPU than other players because it does more than just display
video.

--Brandon