On Thr 18 Jan 2007,
MerriLUG was proud to host Jared Wilson, who presented on MythTV. This page is an attempt to collect some of the notes about the presentation.
The MythTV home page is:
http://www.mythtv.org
Jared's home page is
http://www.wilsonet.com/![](/pub/TWiki/TWikiDocGraphics/external-link.gif)
, which includes a section on
Fedora Myth(TV)ology![](/pub/TWiki/TWikiDocGraphics/external-link.gif)
and links to his recently-released book from Extreme Tech. There's a sample chapter on that website, too.
Sixty-one attendees made it to Martha's Exchange that night, making it the largest dinner ever, and one of the largest meetings, ranking up with Ted T'so and Linus. Jared ran the meeting as a straight Q&A after a brief introduction, and finished with some striking demonstrations of the difference in quality between NTSC and HD captured video.
How it works
The MythTV system downloads it's Electronic Program Guide (EPG) data from
Zap2It.com![](/pub/TWiki/TWikiDocGraphics/external-link.gif)
, via an XML export feature. Zap2It requires free registration for this. Zap2It's motivation is apparently to avoid tons of screen scrapers hammering their web servers. Zap2It is operated by
Tribune![](/pub/TWiki/TWikiDocGraphics/external-link.gif)
(incidentally, TiVo uses the same company for their EPG data). EPG is available 12 days ahead of airdate.
If you have multiple MythTV boxes, you really should try and make sure they all have the same version. Compatability between versions is not good.
Tuner/Capture Hardware
Any card needs to be
Video4Linux (
V4L) compatible. There are dozens of compatible cards. Check the MythTV website for information on what works and what does not.
The Hauppauge
WinTV PVR![](/pub/TWiki/TWikiDocGraphics/external-link.gif)
line is popular. Some notes on models:
- PVR-250 is a good started. The IR receiver (for remote control) is not the best.
- The hardware decoder on the PVR-350 is of limited use.
- The PVR-500 is a dual-tuner card, and functions just like having two PVR-250 cards.
One bit of hardware that Jared recommended was the
HD Home Run![](/pub/TWiki/TWikiDocGraphics/external-link.gif)
, from SiliconDust. It is basically an Ethernet-to-TV bridge. You plug coax into one side, Ethernet into the other, and you're in business. It contains everything you need to tune, capture, encode, and stream a TV signal over the 'net. It can be used with MythTV and other software as a capture device. This lets you put your TV input hardware in a different location than your MythTV backend storage hardware.
Per FCC rule, any modern (within the past few years) digital cable box must have a FireWire port, which will provide the (possibly encrypted) digital video stream. Thus, if you have such a cable box and a FireWire port on your PC, you don't need a tuner/capture card.
Other Hardware
Jared recommended NVidia video display hardware, with the
binary-only, closed-source driver![](/pub/TWiki/TWikiDocGraphics/external-link.gif)
. He also recommended the use of the a config tweak in the X server configuration file: Set "=UseEvents True=". He said the ATI cards can sometimes be made to work, but sometimes not, and all require too much effort.
Lots and lots of disk storage. The more, the better. Standard definition recordings consume about 2.5 gigabytes/hour. High definition recordings consume from 6 to 12 gigabytes/hour.
MythTV has an archving plugin for archiving to DVD.
Any LIRC device (IR remote control) will work.
For playback, a 600 MHz PIII is minimum for std def. High def needs a lot more, perhaps a 2 to 3 GHz P4 or similar. There are a lot of things you can do in the area of performance tuning.
Network streaming (i.e., a recording stored on one box, playing on a different box, over the network) is possible. MythTV uses its own protocol, or you can use NFS/etc. Std def needs about 3 megabits/second. High def can use up to 17 megabits/second. Avoid wireless (802.11) -- even if nominal throughput is there, contention and packet loss will kill you.
Other notes
MythTV currently does not support straight pass-through without a lag for writing to and reading from disk. This is being worked on and may appear soon, perhaps the next release.
Currently, the photo gallery can't show a slideshow while music is streamed, too. This is also being worked on and is coming soon.
Most cables, whether analog or digital, should also be carrying high-definition versions of the over-the-air (PBS, NBC, CBS, ABC) networks. Most local Comcast cables seem to have it QAM-256 encoded.
Other resources
About this document
Provided AS IS. Use information here strictly AT YOUR OWN RISK.
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