[mythtv] DVB: playback and live TV

Fri Aug 22 00:32:19 EDT 2003

Hi 

I'm having problems watching live TV from my DVB card, and playing back 
recordings using mythfrontend. The recordings work perfectly in mplayer. I 
have the latest CVS version of myth (a few hours old) running with my DVB-T 
card. Are there any patches I should have applied for DVB watching?

Here are some details:

When selecting a recording to play back, I'll often be able to see a few 
seconds of video, then the screen goes black. Sometimes I'll get a second or 
two of sound, but no picture, and sometimes I get nothing at all. The program 
doesn't repond to the keyboard so I have to kill it (but it doesn't segfault 
or anything like that). I've pressed Ctrl-C in gdb and done some backtraces - 
at the end of this email.

When watching live TV, sometimes it gives me the same symptoms as for 
playback, and sometimes it works. When it works, changing channel will 
usually mess things up - the screen goes black and I see these messages from 
mythbackend:
IOBOUND - blocking in ThreadedFileWriter::Write()
Backend stuffed up in RequestRingBufferBlock

The recorded files are excellent when viewed with mplayer, so the DVB tuning 
is OK. I'm running an Athlon 1700XP with Mandrake 9.1. Myth is compiled for 
'pentiumpro' and I've compiled with debugging flags. If I'm not missing some 
patchees, could someone look at these to see if they understand what's 
happening?

Thanks.
Neil

Starting program: /usr/local/bin/mythfrontend
[New Thread 16384 (LWP 5476)]
Loading required GL library /usr/X11R6/lib/libGL.so.1.2
connecting to backend server: 127.0.0.1:6543
[New Thread 32769 (LWP 5481)]
[New Thread 16386 (LWP 5482)]
[New Thread 32771 (LWP 5483)]
Input #0, mpeg, from '/video/2_20030819220000_20030819223000.nuv':
  Stream #0.0: Video: mpegvideo, 720x576, 25.00 fps, 6480 kb/s
  Stream #0.1: Audio: mp2, 48000 Hz, stereo, 256 kb/s
[New Thread 49156 (LWP 5484)]
[New Thread 65541 (LWP 5485)]
[New Thread 81926 (LWP 5486)]
Input #0, mpeg, from '/video/2_20030819220000_20030819223000.nuv':
  Stream #0.0: Video: mpegvideo, 720x576, 25.00 fps, 6480 kb/s
  Stream #0.1: Audio: mp2, 48000 Hz, stereo, 256 kb/s
[New Thread 98311 (LWP 5487)]
[New Thread 114696 (LWP 5488)]

Program received signal SIGINT, Interrupt.
[Switching to Thread 114696 (LWP 5488)]
0x40b9ebe6 in nanosleep () from /lib/i686/libc.so.6
Current language:  auto; currently c
(gdb) thread apply all bt full

Thread 9 (Thread 114696 (LWP 5488)):
#0  0x40b9ebe6 in nanosleep () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x00000000 in ?? ()
No symbol table info available.

Thread 2 (Thread 32769 (LWP 5481)):
#0  0x40bc6537 in poll () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x409c896e in __pthread_manager () from /lib/i686/libpthread.so.0
No symbol table info available.
#2  0x409c8bbb in __pthread_manager_event () from /lib/i686/libpthread.so.0
No symbol table info available.

Thread 1 (Thread 16384 (LWP 5476)):
#0  0x40b9ebe6 in nanosleep () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x00000000 in ?? ()
No symbol table info available.
#0  0x40b9ebe6 in nanosleep () from /lib/i686/libc.so.6

*********************************************

Starting program: /usr/local/bin/mythbackend
[New Thread 16384 (LWP 5454)]
Starting up as the master server.
DVBChannel: Changing to channel 3 on card 0
Using DVB card "NxtWave NXT6000"
tuning DVB-T (in United Kingdom) to 529833330 Hz
polling....
Getting frontend event
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Bit error rate: 0
Signal strength: 0
SNR: 0
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
SetPID:  514 652
[New Thread 32769 (LWP 5463)]
[New Thread 16386 (LWP 5464)]
[New Thread 32771 (LWP 5465)]
[New Thread 49156 (LWP 5466)]
[New Thread 65541 (LWP 5467)]
[New Thread 81926 (LWP 5468)]
[New Thread 98311 (LWP 5469)]
[New Thread 114696 (LWP 5470)]
[New Thread 131081 (LWP 5471)]
[New Thread 147466 (LWP 5472)]
2003-08-21 23:20:16 adding: sym as a player 1

Program received signal SIGINT, Interrupt.
[Switching to Thread 147466 (LWP 5472)]
0x40b19568 in sigsuspend () from /lib/i686/libc.so.6
Current language:  auto; currently c
(gdb) thread apply all bt full

Thread 11 (Thread 147466 (LWP 5472)):
#0  0x40b19568 in sigsuspend () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x409cb478 in __pthread_wait_for_restart_signal () from 
/lib/i686/libpthread.so.0
No symbol table info available.
#2  0x409c7c5b in pthread_cond_wait at GLIBC_2.0 () from 
/lib/i686/libpthread.so.0
No symbol table info available.

Thread 10 (Thread 131081 (LWP 5471)):
#0  0x40b19568 in sigsuspend () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x409cb478 in __pthread_wait_for_restart_signal () from 
/lib/i686/libpthread.so.0
No symbol table info available.
#2  0x409c7c5b in pthread_cond_wait at GLIBC_2.0 () from 
/lib/i686/libpthread.so.0
No symbol table info available.

Thread 9 (Thread 114696 (LWP 5470)):
#0  0x40b19568 in sigsuspend () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x409cb478 in __pthread_wait_for_restart_signal () from 
/lib/i686/libpthread.so.0
No symbol table info available.
#2  0x409c7c5b in pthread_cond_wait at GLIBC_2.0 () from 
/lib/i686/libpthread.so.0
No symbol table info available.

Thread 8 (Thread 98311 (LWP 5469)):
#0  0x40b19568 in sigsuspend () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x409cb478 in __pthread_wait_for_restart_signal () from 
/lib/i686/libpthread.so.0
No symbol table info available.
#2  0x409c7c5b in pthread_cond_wait at GLIBC_2.0 () from 
/lib/i686/libpthread.so.0
No symbol table info available.

Thread 7 (Thread 81926 (LWP 5468)):
#0  0x40b19568 in sigsuspend () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x409cb478 in __pthread_wait_for_restart_signal () from 
/lib/i686/libpthread.so.0
No symbol table info available.
#2  0x409c7c5b in pthread_cond_wait at GLIBC_2.0 () from 
/lib/i686/libpthread.so.0
No symbol table info available.

Thread 6 (Thread 65541 (LWP 5467)):
#0  0x40b9ebe6 in nanosleep () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x00000000 in ?? ()
No symbol table info available.

Thread 5 (Thread 49156 (LWP 5466)):
#0  0x40b9ebe6 in nanosleep () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x00000000 in ?? ()
No symbol table info available.

Thread 4 (Thread 32771 (LWP 5465)):
#0  0x40b9ebe6 in nanosleep () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x00000000 in ?? ()
No symbol table info available.

Thread 3 (Thread 16386 (LWP 5464)):
#0  0x40b9ebe6 in nanosleep () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x00000000 in ?? ()
No symbol table info available.

Thread 2 (Thread 32769 (LWP 5463)):
#0  0x40bc6537 in poll () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x409c896e in __pthread_manager () from /lib/i686/libpthread.so.0
No symbol table info available.
#2  0x409c8bbb in __pthread_manager_event () from /lib/i686/libpthread.so.0
No symbol table info available.

Thread 1 (Thread 16384 (LWP 5454)):
#0  0x40bc7ef1 in select () from /lib/i686/libc.so.6
No symbol table info available.
#1  0x409b7024 in typeinfo for QMotifStyle () from 
/usr/lib/qt3/lib/libqt-mt.so.3
No symbol table info available.
Cannot access memory at address 0x11
#0  0x40b19568 in sigsuspend () from /lib/i686/libc.so.6