[mythtv] Development thoughts + Mythtv crashing bug - during playback/delete
Isaac Richards
mythtv-dev@snowman.net
Mon, 9 Sep 2002 15:52:17 -0400
On Monday 09 September 2002 02:29 pm, Grant Taylor wrote:
> Yes, please don't bother. Mythtv is about watching TV. Stuff like
> DVD can be handled with something trivial like
>
> system("mplayer -dvd -blah-blah");
Yeah. On the dvd note, I'll add support for it once playing DVDs in linux
doesn't suck badly.
> Which brings up the point - is the frontend stuff at all scriptable?
> Currently most everything is a thread, which makes it rather hard to
> plug stuff in without writing code that runs in the same context as
> precious stuff like the timed recorder.
What would you want to do with it?
> What's more of a mystery is that I can't find what to put in my
> irxevent rc file for "space". "KP_Space" is the only listed thing in
> the xevent docs, but that doesn't work. Nor does "Space". I'm quite
> sure my remote button works; irw shows it being pushed.
>
> I looked at the example ir config file, and I can see no way to use
> the supported keys to select the "Record this showing" or "Record this
> timeslot" or "Record this title" options. Enter always exits the
> dialog - only a real space on the real keyboard seems to work, which
> is sort of awkward since my keyboard is in the basement!
I'll check that out.. haven't used the remote much lately, mainly been using a
wireless keyboard.
> Does -g change anything else in the way the code compiles? It might
> be a nice if the makefile defaulted to making a -g binary and then
> stripped it at install time. This way people can gdb the unstripped
> exe and core files with symbols.
Turning on debug in settings.pro also turns off the mmx code and some other
optimizations, which can cause problems in gdb. It's a lot easier to debug a
non-optimized binary.
> Also, is there something useful that can be done to snapshot a hanging
> mythtv? A couple times a day the player will hang for about 60-120s
> when I'm in the middle of forwarding or reversing. It just stops,
> with no sound, with the picture and "Forward" or "Reverse" osd overlay
> stuck, but it eventually continues.
>
> It's not crashing or saying anything. I've never noticed any hang or
> jumps in whatever was recording under it at the time; seems like a
> player-specific issue.
>
> What threads are active and waiting on what during ffwd/rew modes?
>
> This is a little odd, the usual failure modes for threaded software
> are "hang forever" and "blow up occasionally". Do you generally use
> semaphores with a 60s timeout or something?
No semaphores, but I bet the A/V sync code's getting thrown off somehow, and
it's waiting for an abnormally long period of time before displaying the next
frame -- happen to know if anything interesting is output to the console?
> Hmm. The mpeg4 support does indeed work, and produces substantially
> smaller files. There are however visible defects in the coding that
> are not present in the rtjpeg codec. Usually, they appear as purple
> or green splotches that last for a few seconds at a frequency of
> several defects per 10 minute period. The splotches seem to be small
> groupings of delta squares; ie they represent a small area of the
> motion between a series of similar frames.
>
> Possibly this has gone away with all the avcodec updates that went in
> over the past week; I haven't updated yet.
I did see those occasionally before I updated libavcodec, and haven't seen
them since. Of course, the problem could still be there and I just haven't
been watching enough TV =)
Isaac