Picture quality on the MythTV is now a lot better. I had been ignoring the transcoder configuration options of the front-end, because my tuner cards, PVR-350 cards, do the MPEG2 encoding in hardware. However, it tuns out that the transcoder options aren’t just for software encoding; on the PVR-350, they also control how the firmware is used for hardware encoding.
In short, we’d been encoding the analogue TV signal with a resolution of 480×480 and a 4:3 aspect ratio. Once I had changed this to 720×576, which is the standard PAL resolution, and used a 16:9 aspect ratio for our widescreen LCD TV, things looked a lot better. Things could still be better, of course, but the quality is now quite satisfactory.
I also changed the encoding algorithm to DVD Special 2, which is apparently the one that Microsoft MCE uses, so in theory the PVR-350’s firmware is optimised for this method. All in all, I think the picture quality is now as good as I’m going to be able to make it.
Unfortunately, I’m still having no luck getting the system to change the channel on the set-top box. I posted an appeal on a site devoted to discussing UPC’s products. That yielded an lircd.conf for the Motorola DPI4000 set-top box, which apparently uses the same IR codes as the Thomson DCI-52UPC that I have. Unfortunately, it didn’t work for me, so the search for a solution goes on.
I also bought a Microsoft MCE IR keyboard a couple of days ago. Linux support for this is still in its infancy, but support for it theoretically does exist in the form of the mod_mce kernel module.
Well, I can get it compiled and inserted into my running kernel, but at the first press of a key on either the keyboard or the remote-control, the entire system freezes. It’s not pingable and the TV picture freezes; even the blinking dots separating the hours from the minutes on the VFD display cease to blink. Whatever that module is doing, it’s not good. So now I have an extra problem to solve; otherwise I’ve wasted €90 on a new wireless keyboard (and it really is a great-looking keyboard).
All in all, we’re getting there. We cleaned up the database to remove duplicate channel listings in MythWeb’s programme guide. My SQL fell short on this task, so Sarah put together a complicated join for me. She’s still a dab-hand at the old SQL.
Speaking of MythWeb, I’ve opened up a port on the firewall to forward traffic from the Internet to the Web back-end. This will be handy when we’re away, because we’ll be able to schedule the recording of new programmes from wherever we happen to be in the world. I was always envious of my TiVo-hacking friends in the States who had this. Naturally, all traffic from outside the home network needs to be authenticated, so digest authentication in Apache 2.2 is taking care of that. I had to figure out how to authenticate outside traffic whilst allowing inside traffic straight through without a password, but that took just a few minutes, thanks to Google.
And that’s where we are right now. We still can’t use the MythTV box for digital cable recordings and we’re still suffering from irritating playback freezes. If I can fix those two problems, plus get the new IR keyboard working, I’ll be a very happy man, indeed.
The box is already providing us with a lot of TV viewing pleasure, however. It’s immeasurably better than the calamitously bad Philips DVDR7300H that we had been using up until last week, although we’ll keep that around for its HDMI DVD-playing capability. In the absence of TiVo, building this box was really the only choice, unless I wanted to buy or build an MCE-based box, but the idea of an inflexible, closed source Windows box was obviously repugnant.
Finally, I must comment on how great it has felt to once again have a technical project to immerse myself in. Choosing the hardware was tedious and putting it all together was an experience frustrating beyond belief (even causing me to shelve the project for a good six months), but once the operating system was installed and I could begin work on the actual MythTV installation and configuration, I was in my element again.
Again, once I iron out the last few serious wrinkles, I’ll be feeling quite satisfied.