[mythtv] HDTV Channel Changing Bug

[Jonathan Watmough]

I seem to have a reproducible bug when changing between certain
channels. Summary :

3 -> Fox OK
3 -> WB OK
Fox -> WB Broken, with continue 'bad stream' printed

But I *can* switch from WB to Fox or vice versa if I go via channel 3.

When I get the 'bad stream' message, I can still switch back to
channel 3 and that works. Then switching to the channel I originally
wanted is ok.

I reproduced what gets printed below. Not sure about the 'desired
subchannel' messages, the subchannel for both these streams is really
3, as verified by using -tsprog 3 in mplayer.

Cheers
Jonathan



switching to channel 3 (This is OK)
-------------------------------
2005-03-15 22:38:01.070 /dev/dtv0 ringbuf avg 1.10352% max 3% samples 47732
2005-03-15 22:39:04.331 prebuffering pause
2005-03-15 22:40:59.455 /dev/dtv0 ringbuf avg 1.10071% max 3% samples 47978
av_remove_stream 0x35
av_remove_stream 0x34
adding pes stream at pid 0x41 with type 2
adding pes stream at pid 0x44 with type 129
closing filter for pid 0x31
av_remove_stream 0x31
closing filter for pid 0x34
closing filter for pid 0x35
streams_changed()
2005-03-15 22:41:56.350 streams_changed() -- stream count 2
2005-03-15 22:41:58.198 AvFormatDecoder: Video has changed from 0x0 to 704x480.

from 3 to Fox (goes to SAP channel - hitting '+' fixes)
------------------------------------------
av_remove_stream 0x44
2005-03-15 22:44:52.056 Desired subchannel 3 not found; using 1 instead
adding pes stream at pid 0x31 with type 2
adding pes stream at pid 0x34 with type 129
adding pes stream at pid 0x35 with type 129
closing filter for pid 0x41
av_remove_stream 0x41
closing filter for pid 0x44
streams_changed()
2005-03-15 22:44:53.184 streams_changed() -- stream count 3
2005-03-15 22:44:53.208 AvFormatDecoder: Video has changed from 0x0 to
1280x720.[mpeg2video @ 0x4096d010]ac-tex damaged at 8 2
[mpeg2video @ 0x4096d010]Warning MVs not available
[mpeg2video @ 0x4096d010]Warning MVs not available
[mpeg2video @ 0x4096d010]ac-tex damaged at 67 5
[mpeg2video @ 0x4096d010]ac-tex damaged at 18 37
[mpeg2video @ 0x4096d010]ac-tex damaged at 73 40

from Fox to WB (Playback is kinda broken / soundless at this point)
-----------------------------------------------------------------------
av_remove_stream 0x35
av_remove_stream 0x34
2005-03-15 22:46:44.396 Desired subchannel 3 not found; using 1 instead
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=338185
[mpeg2video @ 0x4096d010]end mismatch left=178513
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=165077
bad stream
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=276191
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=168926
[mpeg2video @ 0x4096d010]end mismatch left=172997
bad stream
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=262707
[mpeg2video @ 0x4096d010]end mismatch left=142478
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=166121
bad stream
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=246083
[mpeg2video @ 0x4096d010]end mismatch left=155671
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=154930
bad stream
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=269898
bad stream
[mpeg2video @ 0x4096d010]end mismatch left=165954
[mpeg2video @ 0x4096d010]end mismatch left=156680
2005-03-15 22:46:46.303 prebuffering pause
bad stream
bad stream
2005-03-15 22:46:46.310 AvFormatDecoder: Video has changed from
1280x720 to 1920x1088.
bad stream
bad stream

When broken - returning to Channel 3 Fixes it
----------------------------------------------------------
bad stream
2005-03-15 22:50:29.521 prebuffering pause
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
bad stream
adding pes stream at pid 0x41 with type 2
adding pes stream at pid 0x44 with type 129
closing filter for pid 0x31
av_remove_stream 0x31
closing filter for pid 0x34
closing filter for pid 0x35
streams_changed()
2005-03-15 22:50:32.904 streams_changed() -- stream count 2
2005-03-15 22:50:34.473 AvFormatDecoder: Video has changed from 0x0 to 704x480.

Now I can switch back to WB ...
---------------------------------------
2005-03-15 22:51:35.299 /dev/dtv0 ringbuf avg 1.133% max 3.1875% samples 41521
av_remove_stream 0x44
2005-03-15 22:53:36.801 Desired subchannel 3 not found; using 1 instead
adding pes stream at pid 0x31 with type 2
adding pes stream at pid 0x34 with type 129
adding pes stream at pid 0x35 with type 129
closing filter for pid 0x41
av_remove_stream 0x41
closing filter for pid 0x44
streams_changed()
2005-03-15 22:53:37.609 streams_changed() -- stream count 3
2005-03-15 22:53:38.148 AvFormatDecoder: Video has changed from 0x0 to
1920x1088.

Hope this is useful to someone ...