MythTV without hardware decoder/encoder

[stokefan]

Hi all,

I want to build a Linux machine to use MythTV with, preferably to output to MPEG2. I was wondering if anyone had any experience of using a capture card in a MythTV rig which doesn't have an MPEG2 decoder card (like a PVR-250, for example) and what it's performance was like, what the other hardware in the system is etc.

Many thanks!

stokefan

[bgrant]

This can be done as I've been using MythTV for over a year and love it. I'm running it on a Gateway P4 2.2GHz with an 80GB hard drive to store videos. I'm using Slackware 10.1 and the latest mythtv packages from linuxpackages.net. My video capture card is an AverMedia PCI card which is bt878 compatible so Linux driver modules are already built with the standard kernel. I'm not happy with internal card's tuner performance so I use it in Line Input mode with an old VCR plugged in to get my analog cable signal. For changing channels, I built a homemade IR transmitter that connects to the serial port and use it with LIRC, which MythTV automatically uses to change channels if you configure it on the setup menu.

I kept playing with resolutions and bitrates to get the best quality, performance, and size ratio. Finally settled on 480x480 at 5500 bps. You can then use nuvexport to export the shows to DVD format after cutting commercials. I've found that now avidemux2 will even edit the raw nuv files that myth records.

[stokefan]

Thanks for the informative post bgrant, can I ask if you use a separate front end and back end setup? Or do you just use the same machine for both recording and viewing?

I'm hoping to build a front end and back end in one box which looks nice enough to put under my television, and then use the TV-Out on the graphics card to output to the TV.

Do you find that the machine runs fast enough to decode TV programs in realtime? I'd be really interested to hear your complete rig specifications.