[mythtv] RE: [patch] dvb problems

Torbjörn Jansson torbjorn.jansson at mbox200.swipnet.se
Sat Jan 31 16:25:24 EST 2004


> > I have tested that i can tune to a channel with "czap channel 
> > name -r" and that i can watch it with mplayer. I also got vdr
> > working.
> 
> The card should have been working with that warning message above,
> please send the output of mythbackend, when you try to go into
> LiveTV or start a recording.
> 

The dvb card I have is a technotrend (hauppauge) dvb-c with mpeg2 decoder
and tvout.
I think the problems I have is atleast partly driver problems and probably
something in mythtv too since vdr usualy works better.

When I use vdr it outputs the picture via dvbc tvout, and it looked like it
was lots of reception errors, blocky picture and weird audio.
And when I ran mythbackend it had problems tuning to channels and I got all
sorts of strange error messages, unfortunately I didn't log it to a file.

After that I have been messing with the drivers and it looks like its
working better now. I don't know exactly what fixed it or if its just
temporary, but I was able to make a short test recording.
One intresting "feature" is that when mythbackend is running and has tuned
to a channel the video is sent out thru the tvout and the same for audio.

So I'm guessing that if there is some problems with the dvb driver it can
appear as bad reception.

I have attached a backend log when I recorded the test.
I ran mythbackend from gdb and I coudnt figure out how to redirect stderr to
the logfile so I did some cut and paste to a new file.


I think that the dvb setup is too complicated, take for example the channel
setup and all the numbers and stuff that has to be entered.
On set top boxes you never have to mess with channels or atleast it's a lot
easier.
So it woud be nice with a channel scanning option like the scan program in
dvb-apps from linuxtv.org

During my testing of the dvb card I managed to get lots of zero length
files, for example when mythbackend cound't tune to the channel. When i try
to delete those file mythbackend output lots of log messages about not being
able to read the file and mythfrontend is slower than normal.
-------------- next part --------------
2004-01-31 21:17:09 Probed: /dev/video0 - Television
2004-01-31 21:17:09 Probed: /dev/video0 - Composite1
2004-01-31 21:17:09 Probed: /dev/video0 - S-Video
2004-01-31 21:17:09 Probed: /dev/video0 - Composite3
2004-01-31 21:17:09 Probed: /dev/video0 - Television
2004-01-31 21:17:09 Probed: /dev/video0 - Composite1
2004-01-31 21:17:09 Probed: /dev/video0 - S-Video
2004-01-31 21:17:09 Probed: /dev/video0 - Composite3
2004-01-31 21:17:10 DVB#0 Using DVB card 0, with frontend VES1820 based DVB-C frontend.
2004-01-31 21:17:10 DVB#0 CAM - Initialized successfully.
2004-01-31 21:17:10 DVB#0 Trying to tune to channel 12.
2004-01-31 21:17:10 DVB#0 Frequency: 394000000 Symbol Rate: 6875000. Inv:Auto Fec:Auto Mod:64
2004-01-31 21:17:10 DVB#0 Waiting for frontend event after tune.
2004-01-31 21:17:15 DVB#0 Status: CARRIER | VITERBI | SIGNAL | SYNC | LOCK.
2004-01-31 21:17:15 DVB#0 Successfully tuned to channel 12.
2004-01-31 21:17:15 DVB#0 CAM - Cached PMT found.
2004-01-31 21:17:15 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
2004-01-31 21:17:15 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
2004-01-31 21:17:15 mythbackend version: 0.14.20040123-1 www.mythtv.org
2004-01-31 21:17:15 Enabled verbose msgs :all
2004-01-31 21:17:15 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
--- print list start ---
Title                 Chan  ChID  StartTime       S I C  C R O N Priority Total
<lots of recorings cut out>
---  print list end  ---
2004-01-31 21:17:16 Found changes in the todo list.
--- print list start ---
Title                 Chan  ChID  StartTime       S I C  C R O N Priority Total
ppv nu                  12  1012  Jan 31 09:19pm  2 3 2  0 1 0 2        0    2
<lots of recorings cut out>
---  print list end  ---
2004-01-31 21:20:14 Found changes in the todo list.
2004-01-31 21:20:14 Started recording "ppv nu" on channel: 1012 on cardid: 2, sourceid 2
2004-01-31 21:20:14 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
2004-01-31 21:20:14 Changing from None to RecordingOnly
2004-01-31 21:20:14 Using profile 'Default' to record
2004-01-31 21:20:14 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
2004-01-31 21:20:14 DVB#0 Recorder: Card opened successfully.
2004-01-31 21:20:14 DVB#0 CAM - Cached PMT found.
2004-01-31 21:20:14 DVB#0 Adding pid 4369, type 0
2004-01-31 21:20:15 DVB#0 Adding pid 4113, type 1
2004-01-31 21:20:15 DVB#0 WARNING - Transport Stream Continuity Error. PID = 4369
2004-01-31 21:20:15 DVB#0 PID 4369 contcounter 6 cc 0
2004-01-31 21:20:58 switching to overrecord for 300 more seconds
2004-01-31 21:25:58 Changing from RecordingOnly to None
2004-01-31 21:25:58 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
2004-01-31 21:25:58 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
--- print list start ---
Title                 Chan  ChID  StartTime       S I C  C R O N Priority Total
<lots of recorings cut out>
---  print list end  ---
2004-01-31 21:25:59 Found changes in the todo list.
2004-01-31 21:25:59 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
2004-01-31 21:25:59 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
2004-01-31 21:26:01 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
2004-01-31 21:26:01 Estimated bitrate = 64000
2004-01-31 21:26:02 Position map found
2004-01-31 21:28:53 DVB#0 ERROR - Poll failed while waiting for Section
          (4) Interrupted system call
-------------- next part --------------
(gdb) run -v all 2>&1 >/tmp/backend.log
Starting program: /usr/local/bin/mythbackend -v all 2>&1 >/tmp/backend.log
[New Thread 16384 (LWP 1841)]
Starting up as the master server.
[New Thread 32769 (LWP 1855)]
[New Thread 16386 (LWP 1856)]
[New Thread 32771 (LWP 1859)]
[New Thread 49156 (LWP 1860)]
[New Thread 65541 (LWP 1861)]
[New Thread 81926 (LWP 1862)]
[New Thread 98311 (LWP 1863)]
[New Thread 114696 (LWP 1864)]
[New Thread 131081 (LWP 1865)]
[New Thread 147466 (LWP 1866)]
[New Thread 163851 (LWP 1867)]
[New Thread 180236 (LWP 1868)]
[New Thread 196621 (LWP 1869)]
[New Thread 213006 (LWP 2125)]
[New Thread 229391 (LWP 2126)]
Audiostream: Layer: 2  BRate: 64 kb/s  Freq: 48.0 kHz
Videostream: ASPECT: 4:3  Size = 352x576  FRate: 25 fps  BRate: 3.10 Mbit/s
[Thread 229391 (LWP 2126) exited]
[Thread 213006 (LWP 2125) exited]
[New Thread 245776 (LWP 2274)]
[New Thread 262161 (LWP 2302)]
Input #0, mpeg, from '/mnt/store//1012_20040131212000_20040131212000.nuv':
  Stream #0.0: Video: mpeg2video, 352x576, 25.00 fps
  Stream #0.1: Audio: mp2, 48000 Hz, mono, 64 kb/s
[mpeg2video @ 0x472026f8]ac-tex damaged at 6 25
[mpeg2video @ 0x472026f8]concealing errors
[mpeg2video @ 0x472026f8]Warning MVs not available
[Thread 262161 (LWP 2302) exited]
[Thread 245776 (LWP 2274) exited]



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