Can Someone Explain This?

[J3M]

I've been having some issues authoring DVD's. The main problem has been with audio. After getting some helpful suggestions here, I experimented a lot this past weekend. Here's what I found:

I'm using ATI MMC 8.9 to capture. My older footage was captured in 720x480 NTSC and audio was 48khz 16 bit MP2. I then recaptured the same footage using the same video settings but switched to MPEG2-DVD which allowed me to save the audio as LPCM. Now, if I did not demux my file, audio still would not play. However, if I allowed DVD Lab to demux and convert my PCM file to WAV before authoring the DVD, it played just fine. I also found that if I didn't demux my files with the MP2 audio, and turned my audio setting on my DVD player (Toshiba SD-3750) from bitstream to PCM they would also work. So, a straight MPEG file even with PCM audio wouldn't play, but demuxing to wav then authoring works. Not demuxing my files with MP2 audio and then changing my audio output in my DVD player would also work.

I also found that if I did demux my files with MP2 audio that the audio wouldn't play no matter what my audio settings on my player were set at. I'm just a bit confused as to why this is happening. I want to be able to author standard DVD's that will play on the vast majority of players, so what do you all suggest? BTW, I am using an optical out on my DVD player into my av amp, so bitstream is the preferred setting.

I hope all of that is as clear as mud.

[SLK001]

MP2 isn't a legal format for NTSC videos. Don't know if that is what your problem is, though.

The difference between LPCM and WAV is a tiny header at the start of the WAV. Maybe your software can't recognize the stream as a valid audio file.

[J3M]

Ah, so this header is being "fixed" when DVD Lab muxes the files back together? I was just confused by all of that. Obviously I've fixed my problem, but it just seems like I'm going through a few extra steps now to get my standalone to play the DVD's correctly.

When MMC is capturing my audio using the LPCM format, why isn't it compliant right away?

[SLK001]

Some programs can handle LPCM, some require WAV. Go figure.