[mythtv-users] firewire xvmc issue

[Bryan Murphy]

Brad,

I've got a similar problem with my 6200 box.  I also have a problem 
where playback of some recordings cause the frontend to crash.  The 
crashing problem consistently happens in NuppelVideoPlayer.cpp on line 
1603 during threaded wait call.  I suspect both problems are related, 
but haven't gone through the steps yet to prove that out.

I'm trying to track down the cause, but I have precious little time and 
have not done any previous work with the QT threading architecture, so 
it's taking me awhile.

Rest assured, somebody is trying to figure out what is going on! :)

Bryan

Brad Zawacki wrote:
> I've got a motorola 6200 cable box that I recently hooked to my mythbox
> via firewire.  I initially had problems with the connection, but CVS
> fixed that with the addition of broadcast connections.  It mostly works
> now, and with xvmc enabled I'm able to watch live HD on my 1.8Ghz p4
> machine at about 70% CPU usage.  
> 
> The problem is that xvmc causes problems with channel changes on the firewire
> connection.  The 6200ch script executes fine, and the backend has no
> errors, but the frontend either prebuffer-waits forever or dies.  
> 
> Best case with '-v playback' I get this:
> 
> 2005-03-15 23:26:58.602 waiting for prebuffer...
> 2005-03-15 23:26:58.602 rate: 29.97 speed: 1 skip: 1 = interval 33366
> 2005-03-15 23:26:58.603 Set video sync frame interval to 33366
> [mpegvideo_xvmc @ 0xb79fd854]Warning MVs not available
> 2005-03-15 23:26:58.656 No codec for stream index 1
> 2005-03-15 23:26:58.657 No codec for stream index 1
> 2005-03-15 23:26:58.658 No codec for stream index 1
> 2005-03-15 23:26:58.658 No codec for stream index 1
> 2005-03-15 23:26:58.736 prebuffer wait timed out..
> 2005-03-15 23:26:58.737 waiting for prebuffer...
> ...
> 
> ...and it goes on forever like this, with the screen frozen.
> Worst case I get this:
> 
> [mpegvideo_xvmc @ 0xb79fd854]ac-tex damaged at 5 0
> [mpegvideo_xvmc @ 0xb79fd854]Warning MVs not available
> [mpegvideo_xvmc @ 0xb79fd854]ac-tex damaged at 3 1
> [mpegvideo_xvmc @ 0xb79fd854]ac-tex damaged at 0 2
> 2005-03-15 23:31:02.801 prebuffer wait timed out..
> 2005-03-15 23:31:02.802 waiting for prebuffer...
> [mpegvideo_xvmc @ 0xb79fd854]ac-tex damaged at 0 3
> [mpegvideo_xvmc @ 0xb79fd854]ac-tex damaged at 0 4
> [mpegvideo_xvmc @ 0xb79fd854]ac-tex damaged at 10 5
> ...
> 2005-03-15 23:31:06.374 prebuffer wait timed out..
> 2005-03-15 23:31:06.374 waiting for prebuffer...
> *** glibc detected *** double free or corruption (!prev): 0x0a239510 ***
> Aborted
> 
> ...and the front end goes away, sometimes taking the backend with it. I
> 'think' that the first example happens when changing to a SD channel,
> and the second when changing to a HD channel, but I'm not positive that
> it's the difference.
> 
> Google hasn't helped me much with the glibc thing, but it seems like it
> might be a significant library conflict.  I don't know how to fix it.
> 
> 
> Any help is appreciated.
> -BZ