Haenlein-Software Forum

I've created a DVD with 1 one hour and 4 half hour titles on, using DVR-Studio Pro 1.56 and DVR-Compress 1.10.

When I play the DVD the 1 hour recording develops a noticable audio delay about 20 minutes in, which then gradually gets worse.

I looked at the logfile and can see that a number of audio errors were encountered during the demuxing of this title. It looks like there are some problems with the audio frames in the file.

Are there any settings that I can change that will improve things, or could the demuxing be modified to replace any corrupted audio with an equivalent duration of silence?

Source machine is a Humax PVR-9200T.

Best Regards
Dave



[snip]
\ CPlusFunctionMgr::FnDemultiplex
\ CDVRStudioDoc::OnOpenDocument
Opening File: C:\Documents and Settings\Dave\My Documents\My Videos\20070226 1859 i7Wainwright - The .ts
\ CDVRStudioDoc::PreAnalyze
\ CDVRStudioDoc::DetectByteOrder
/
/
/
\ CDVRStudioApp::CreateSubDirs
/
\ CMpegTsDemux::Init
/
Demultiplexing recording to separate MPEG ES:
First Video PTS is 0:01:07,354
First Audio PTS is 0:01:07,368
First Audio PTS is 0:01:07,392
MPEG Audio format change detected!!!
Audio may not be working for DVD-Authoring!!!
Found invalid audio frame @ PTS 0:17:38,568
Found invalid audio frame @ PTS 0:17:38,688
MPEG Audio format change detected!!!
Audio may not be working for DVD-Authoring!!!
MPG Audio PID: 0191, PTS: 0h16:31,414
Too many missing sound frame(s) detected! 385ms
Dropping corresponding GOP
Video PID: 00C9, PTS: 0h16:31,560
Dropped GOPs! 0ms
MPEG Audio format change detected!!!
Audio may not be working for DVD-Authoring!!!
Found invalid audio frame @ PTS 0:17:46,488
MPEG Audio format change detected!!!
Audio may not be working for DVD-Authoring!!!
MPG Audio PID: 0191, PTS: 0h16:39,333
Too many missing sound frame(s) detected! 408ms
Dropping corresponding GOP
Video PID: 00C9, PTS: 0h16:39,360
Dropped GOPs! 0ms
MPEG Audio format change detected!!!
Audio may not be working for DVD-Authoring!!!
Found invalid audio frame @ PTS 0:19:10,848
Found invalid audio frame @ PTS 0:19:10,849
MPEG Audio format change detected!!!
Audio may not be working for DVD-Authoring!!!
MPG Audio PID: 0191, PTS: 0h18:03,576
Too many missing sound frame(s) detected! 363ms
Dropping corresponding GOP
MPG Audio PID: 0191, PTS: 0h18:03,693
Padded missing sound frame(s): 44ms!
Video PID: 00C9, PTS: 0h18:03,840
Dropped GOPs! 0ms
Found invalid audio frame @ PTS 0:28:14,904
Found invalid audio frame @ PTS 0:28:14,928
Found invalid audio frame @ PTS 0:28:14,952
Found invalid audio frame @ PTS 0:28:14,976
Found invalid audio frame @ PTS 0:28:14,904
Found invalid audio frame @ PTS 0:28:14,928
MPG Audio PID: 0191, PTS: 0h27:07,677
Padded missing sound frame(s): 48ms!
MPG Audio PID: 0192, PTS: 0h27:07,677
Padded missing sound frame(s): 48ms!
MPEG Audio format change detected!!!
Audio may not be working for DVD-Authoring!!!
Found invalid audio frame @ PTS 0:40:15,768
MPEG Audio format change detected!!!
Audio may not be working for DVD-Authoring!!!
Found invalid audio frame @ PTS 0:40:15,769
Found invalid audio frame @ PTS 0:40:15,787
Found invalid audio frame @ PTS 0:40:15,888
MPEG Audio format change detected!!!
Audio may not be working for DVD-Authoring!!!
MPG Audio PID: 0191, PTS: 0h39:08,630
Too many missing sound frame(s) detected! 425ms
Dropping corresponding GOP
Video PID: 00C9, PTS: 0h39:09,000
Dropped GOPs! 0ms
Reached end of stream.

Synch Summary:
Skipped or missing Video Frames: 320ms
Skipped or missing Audio Frames: 1582ms
Skipped or missing Audio Frames: 312ms
Runtime Summary:
Total video runtime: 0h59:03,760
Total audio runtime: 0h59:02,629
Total audio runtime: 0h59:03,925
Done, 511s

/
[snip]

From which TV-channel is this recording from?

There is not much that can be done about it. If there are so many errors in there I would suspect bad reception during recording.

BBC4 in the UK, and usually BBC is pretty good

There are no obvious dropouts when I playback on the PVR, and I think I've located the point in the recording where the first major slip occurs. Unfortunatly it's a quiet moment though it's possible that I can hear some slight change but video is fine with no break up. Maybe there some audio only errors introduced prior to transmission.

How about the suggestion of padding the larger corrupted gaps with 'silence frames'? As it is now the audio track is just over a second shorter than the video tracks hence the loss of video/audio sync.

Alternatively perhaps an option to drop the video as well as the audio for the corrupted period. Might lose occasional 0.5 seconds but would be less noticable than loss of sync.

Let me know if I can try anything or help in some way.

Thanks
Dave

As you can see DVR-Studio is already trying to fill in silent frames and drop GOPs, whichever is more appropriate. In this case an additional problem is there: a change in audio format. Looks like the format is changing from stereo to mono or something like this. Maybe this is just because of some unfortunate bit-errors (its just 1 or 2 bits distinguishing the format). So there is not much we can do about it, I'm sorry.

If this happens often with recordings of this channel, then I would be interested in a sample file containing such an error. You would have to use cut-areas and "copy edited recording" to isolate an error. Let's say in this case the arey around 0h17m.
1 minute of recording usually results in 30MByte of size, which you could upload on our FTP server.

Hi. I've worked around the problem by cutting the affected bits out with a bit of trial and error!
I've edited out a 1 minute fragment of the original programme (~34mb). 0:17 to 0:18 which should include the first two audio dropouts.
PM me the ftp server details and I'll upload it.
Cheers
Dave