[NBLUG/talk] Freevo/MythTV -

[Scott Doty]

On Sat, Jun 07, 2003 at 02:19:35PM -0700, Mark Street wrote:
> Has anyone setup a Linux based Freevo or MythTV box/network?  I have been 
> playing with my DV recorder filling up hard disks editing DV, and Scott and 
> his TV capture card.  This stuff has me interested

I set up MythTV this weekend.  (Note that the web site says the guy plans a
new release tonight.)  Very nice, but not without problems.

First, it is very, very easy to use, but requires some fu to get set up. 
For instance, you need to get mysql up and running somewhere on your
network.  Also, with Redhat 9, you need to set the QTDIR environment
variable, or the build will choke big-time.

There are some other "gotchas" -- I recommend a thorough reading of
   http://www.mythtv.org/modules.php?name=MythInstall

 ...before embarking on the MythTV adventure.

On the plus side, it is very easy to schedule a show for recording.  (It
also has the tivo-like feature of being able to record every instance of a
particular show.)  The downside:  as far as I can tell, this is the _only_
way to record:  schedule it from the TV-Guide menu.   There's no way to say
"record this now".

Another plus:  The live-pause and rewind-live features work great.  However,
you'll be hard-pressed to find the keystrokes documented -- I couldn't find
them anywhere until I looked at the IR remote definition files.
(configfiles/lircrc.example.zenithvcrplus in the source tree.) Note that you
need a pretty fast and modern processor to handle encoding and decoding
audio/video at the same time, which is what happens when you watch TV.

A serious minus:  The video files MythTV creates are its own format. 
avidemux had a patch to be able to read these files -- but then, it appears,
the file format changed.  (Neither ffmpeg or mencoder can handle the format
either.)  I'm in discussion with the avidemux author about the problem, and
I intend to bring it to the MythTV dev list.  (The video file format just
can't be a moving target!)

I should note that the MythTV docs say to abandon your Gnome desktop for KDE
for it to work correctly -- something about certain windows obscuring other
windows.  http://www.mythtv.org/docs/mythtv-HOWTO-18.html#ss18.3  (There's
a sterner warning than that in the docs, but I was unable to find it with a
cursory look.)

Then there's the issue of soundcard handling.  The MythTV guys recommend
using ALSA sound drivers.  I'm using OSS and the Audigy module from
opensource.creative.com -- seems to work fine, but with a caveat:  I have to
run gnome-volume-control, select line-in for recording, set the level, and
click mute, and then NOT exit the application.  Then I set up MythTV to use
/dev/dsp1 for playback.  Getting audio set up for your system would seem to
be the toughest task -- your mileage may vary.

Finally, I should mention that, with some experimentation, I was able to get
mencoder/mplayer to work together to do video recording and immediate
playback with "live pause".  It's kind of kludgy, but it works.  My current
mencoder line for video capture:

   mencoder -tv on:driver=v4l:width=384:height=288:input=1:norm=NTSC:adevice=/dev/dsp \
        -o $1 -oac mp3lame -ovc lavc

...with "$1" being the filename.  Then, with that running, you start mplayer
thusly:

   mplayer -idx -ao oss:/dev/dsp1 $1

...with "$1" being the filename again.  The "-idx" tells mplayer to index
the file so you can seek.  Note, however, that with a live stream being
recorded to the file, mplayer will only be able to seek to the point where
it was at when you first ran mplayer.  So, you can do your "live pause" all
you want, but if you want to "catch up",  you have to stop mplayer, re-run
it, then seek around until you're at the video you want to watch.

Again:  Kinda kludgy, but it works.

Hopefully this is useful for anyone trying to figure out Video4Linux.  Take
care...

 -Scott