Happaugge PVR audio issue ...

[Anonymous]

When converting a 30gig MPEG2 file to DivX5 using VirtualDub I get "MPEG-1 audio decode error: incomplete frame".
Capping using hardware MPEG2 compression on Happaugge PVR pci at best quality (12mbit/s CBR).

I purchased VideoReDo after reading lots of good stuff about it in the forums and yes - it does seem to fix stuff - just not the incomplete frame error! I've heard that the issue is cos VirtualDub is fussy about mpeg2 streams or something but I was hoping that VideoReDo would sort it.

Is VideoReDo supposed to fix this? Otherwise, does anyone know any other way to fix this and still use VirtualDub??

Thanks for your help ... Rob

[DanR]

Rob, There are 2 types of possible audio frame errors although I'm not sure which one(s) VirtualDub is looking for. One possible error are dropped or partial audio frames. The PVR board is notorious for creating these error. These result in missing or corrupt frame headers. VideoReDo detects these and corrects them along with resulting possible sync issues. There should never be bad frame headers in the output file created by VideoReDo.

The 2nd error might be bad data within an audio frame. VideoReDo doesn't look inside the audio frame when creating the output file, only during playback.

If you want me to look further into this, then upload a small clip (10-20mb) which duplicates the problem and I'll see what I can find.

A future release of VideoReDo will support changing the audio bitrate. When this is available, then the audio will be decoded and recoded during output.

[Rob Dunn]

Cheers for the quick response.
I've got two Mpeg2 files that get the error but they're both 30+gig TV recordings.
I will try to record something a little smaller.
Where should I upload it?

Thanks ... Rob.

[DanR]

Rob, The first topic in this forum has the upload information.

http://www.drdsystems.com/forum/phpBB2/viewtopic.php?t=92

[Rob Dunn]

I can't seem to recreate the incomplete audio frame error by capping 15-20meg of video. Also, just to really help, VirtualDub won't let me cut the bad bit out to a seperate file - I just get the same error.

VideoReDo to the rescue - it was more than happy to cut the bad bit out into a 3.5meg file "Audio Error.mpg" which I've uploaded to your "Upload" directory.

[DanR]

VideoReDo to the rescue - it was more than happy to cut the bad bit out into a 3.5meg file "Audio Error.mpg" which I've uploaded to your "Upload" directoryJust to be clear, this 3.5MB will trigger the audio error with VDub? Is is there a particular version and/or plug-in I need to load for VDub?

[Rob Dunn]

I have just zipped my virtual dub directory and uploaded it aswell - I hope this helps. It's version 1.5.1 build 15654 but I think it may be a modified version that deals with mpeg2.

You may not need to use Virtual Dub to see (or hear) the problem - I just played back the dodgy 3meg file and there is a nasty sounding blip right where virtual dub fails!

[DanR]

Rob, Thanks for the uploads. VDub failed right where you said it would. However, our own internal MPEG audio decoder doesn't recognize any error within the stream, so even though there's a crackle at that point, we don't detect it as being in error. All I can suggest at this point is to manually remove the bad area in VideoReDo and re-try the compression.

[Rob Dunn]

I suspected as much. I'll try to identify the exact frame and remove it using VideoReDo - hopefully it won't be too noticable.
Thanks for your help.

BTW this audio bitrate feature you are adding - do you think would help and if so is there an eta?

[DanR]

BTW this audio bitrate feature you are adding - do you think would help and if so is there an eta?Yes, the audio bitrate feature will fix this problem. The crackling frame will still be there, bit it will be re-encoded into a "valid" cracking noise. :)

ETA is 1-3 months with the emphasis on "Estimated".