test the nation

I scored 55 out of 70 on CBC’s Test the Nation quiz. I suck at Canadiana, apparently… :)

posted at 8:29 am on Tuesday, September 18, 2007 in Personal | Comments Off on test the nation

MythTV PVR-250 settings

For posterity, the resolutions and bitrates I’m now using for recording shows with the PVR-250 on my MythTV box. The “Low Quality” setting is definitely degraded, but watchable; probably because of the reduced resolution more than the reduced bitrate. The “High Quality” setting looks to be good enough for DVD transfers. “Default” produces files that are about 1.5G/hour (my old settings were producing 2.2G/hour, so this will let me record more stuff). I may change them some more, of course…

profile resolution bitrate (avg/max) audio sample audio bitrate
Default 720×480 4000/5000 48K 224K
High Quality 720×480 6000/6500 48K 384K
Low Quality 320×480 2000/2200 32K 192K
Default 720×480 4000/5000 48K 224K
Old Default 480×480 4500/6000 32K 320K

I’ve read that the audio settings don’t make any difference with the PVR-250, only the “master” bitrate. Whatever :)

posted at 10:48 am on Sunday, September 09, 2007 in Personal, Science and Technology | Comments (1)
  1. Reid says:

    Given current CPU speed, is transcoding to DivX or something feasible? That would reduce recording disk usage to about 350 MB/hr.

mythtv upgrade

zap2it decided to get out of the free TV listings business (and I’d like to thank them for maintaining free listings for as long as they did!). There’s a replacement, subscription-based service called for MythTV users Schedules Direct, but converting to it requires some database changes, which essentially meant “upgrade!”. So I did; to KnoppMyth R5F1.

This was a major upgrade; kernel 2.4 to 2.6, and MythTV from 0.16 to 0.20, so I was expecting trouble. I made a complete disk2disk copy of my PVRs harddrive, and then ran the KnoppMyth backup utilities also.

As it turns out, KnoppMyth is suprisingly easy to upgrade. All of my important settings were copied over intact, and the box did sort of work after the reboots. However, I had to do a number of things manually:

  • convert my tv listings source from zap2it to schedulesdirect. Unfortunately, this required re-building MythTV from source, which took all day.
  • Recompile the kernel without the vesafb driver (which I remembered thanks to my old posting: PVR 250 and MythTV)
  • get my Matrox G400 tv-out working, which was basically copy over my old scripts that would sync the framebuffers and adjust the video output
  • fix the audio volumes, again
  • rebuild the lirc modules, since the kernel source I grabbed from mysettopbox.tv didn’t have these modules already

That was about it. It dig take all day (kernel and myth rebuilds are slow on a PIII-933), but the box seems to be working ok; playback of TV and DivX works, I can record TV shows, and (the reason for the upgrade!) I have TV listings again…

One issue: the console is totally useless until X starts; something is setting the framebuffer to a very strange mode. That’s a problem for another day…

posted at 9:30 pm on Saturday, September 08, 2007 in Personal, Science and Technology | Comments Off on mythtv upgrade

server update

I decided to try out Linode (300Mb RAM, 8Gb disk space for $20/month), since they support Ubuntu 7.04 and have a better memory model and kernel support. So far so good; persephone.cfrq.net has been a virtual server since Wednesday! The migration was trivial; I bought a new linode installation, booted it up, and used rsync to copy files from the old server to the new one. It took about 6 hours altogether. Then I shutdown all the services on the old box, did one final rsync, and updated the DNS to point to the new server. Everything came up right away; I’m not sure if anyone even noticed the change :).

I haven’t decided if I’m going to keep it here or not yet, but I’ve bought myself some procrastination time!

posted at 11:39 am on Friday, September 07, 2007 in Site News | Comments Off on server update