Audio reencoding and skips

[chimera]

I've done a search for this and wasn't able to find the information I was looking for.

After I compile a DVD of a Tivo stream (not reencoded, straight stream to DVD using DVD Maestro), when played on a DVD player it sometimes has a half second audio skip causing the audio to disappear for a half second. While this isn't too bad, it can be annoying, especially when you are listening to someone talking.

I can't help but think this is the DVD Player (Pioneer 440) having problems reading the audio stream that came from my DirecTivo. I know Dave puts lots of crazy things in the video file, and I'm sure he did audio the same.

I was wonder, has anyone else has similar problems? If so, what did you do to correct it? I thought if I could reencode the audio to a correctly formated .ac3 or pcm file it would fix my problem. But programs like Soft Encode seem to have a problem doing anything with the audio file.

[BD38]

chimera -

I use a 440 and it plays TyDVD's great, including mp2 audio, although it's not technically legal for DVD. I'm assuming that you've listened to the audio on your PC at the point where you have the dropout and it doesn't exist there? Do all your DVD's have this problem? If you're going to convert the audio to AC3 with SoftEncode, this requires a conversion to wav first.

[chimera]

Actually I stand to be corrected. When played in the PC, it exists there too. It does not exist if I play the original recording on the Tivo. So what does this mean? It is getting tainted somewhere between the Tivo and the DVD. I have used two different burn programs, Maestro and SpruceUP..same thing. I use jdiner's Tytool 4 to extract and split.

Any program in particular that can convert the .mpa to .wav and retain the DD stream?

[BD38]

I would try vspliting again using the standalone vsplit if you haven't already. Since there is no video corruption it sounds like the extraction went OK. Any of the popular tools like Winamp can be used to convert the mpg audio stream to wave, but if you hear a problem with the mpg audio after vsplitting it's going to exist after any conversions. I'm assuming that this is not a DD 5.1 stream.

[chimera]

Fortunately it is a DD 5.1 stream. Any idea on how to convert to Dolby Digital .wav and retain the 5.1 channels?

[BD38]

The audio stream from vsplit that was used on a ty file that contains only DD audio is in AC3 format. You should be able to open this file in SoftEncode(use "AC-3 frame view" for quicker loads and "decode to PCM" if you want to play the file in SoftEncode) and it will tell you info about the ac3 file - # of channels, bitrate, etc. If you can't open the file in SoftEncode then it's not a valid AC3 file and it's not DD 5.1. What happens when you open the ac3 file in SoftEncode?
Most, if not all, DD 5.1 programs have audio at the head and tail that is not DD. Use the -j and -l options of vsplit to get only the DD 5.1 portions of the file. Vsplit will say the file is DD 5.1, but it looks somewhere in the middle in the file to obtain this info. The head and tail of the ty file could be Layer II or DD 2.0.
What movie/show are you trying to do?

[chimera]

Thanks for all the tips. Get this, it doesn't make sense:

-After seperating the .ty file using the newest vsplit, the resulting audio file plays on the computer with a skip of audio at a certain point. This skip is about half a second.

-This skip, when burned on a DVD, causes my Sony receiver to go from DD 3/2 to no input to DD 3/2. This switch back and forth makes the "skip" seem much longer, from a half to almost a full second.

-By using your types, I was able to convert the audio file to PCM in Soft Encode, then back to ac3. After burning to a DVD, I noticed NO SKIP is there anymore.

This makes me think it wasn't a bad source, but that the audio headers in this particular stream caused most playback devices to skip a few frames of audio. By reencoding the audio into standard ac3, the headers were replaced with new ones, resulting in no frame loss. This is just a guess though. But if anyone else runs across a crazy stream like that, maybe it will help them out.