44100 to 48000 out of sync

[smeg]

A while ago I backed up several films from VHS to VCD, the thing is I want to put the onto DVD now, from the VCD. When-ever I convert the audio from 44100 to 48000 it goes out of sync. I have checked and adjusted the length of some of these and the still go out of synch.
Any ideas?
Thanks in advance.

[pijetro]

What tools are you currently using for sample conversion???

[smeg]

I've tried Goldwave and Cool Edit Pro 2.

[pijetro]

If you are doing a 41khz to 48khz resample with Cool Edit, there shouldn't be a problem. The play lengths should be identical. Just to be sure, save your .MP2 as a .WAV file first, then do the conversion. That might be a first start.
After your .wav has been recompressed to .MP2 (or .AC3), what do you mux the streams with???

Give a few more details. It might not be what you think.

[Dan East]

Is the audio out of sync playing on your PC, or in a DVD player? I tested around a dozen DVD players, and only one could properly handle 48kHz audio for VCD. All but one had one of three problems:

Audio out of sync
Intermittant audio (Apex, Sony)
Audio is synched, but lower-pitched than it should be (Pioneer)

The only player I've found that can handle 48khz audio with mpeg1 it is the ACI FLEX-1000B.

Dan East

[pijetro]

Why would you do such a futile search of players that accept 48000 audio for VCD format, when it's clearly not within spec?? Do you honestly find a difference in audio, since CD quality is 41000 to begin with??

[Dan East]

Before I discovered that TMPGEnc's audio encoder sucked, the only way I found to make it create decent sounding audio was to encode at 48kHz. Now I use HeadAC3he and encode at 44kHz.

Dan East

[pijetro]

Well, it's not the greatest, but it isn't that bad either. People have the complaint that Tmpgenc doesn't do a good job of adjusting the sample rate. Even then, if you go to the external tools under the options section, many people use Toolame as a plug-in audio encoder....

One way or the other, just to avoid any hassles, here's a tip that works for me. Whenever converting samplerates, always do it while the audio is in .wav format. Even the cheapest audio software should be able to handle that correctly. Then recompress to .AC3 or .MP2 without probs.

I've found that problems arise when people convert samplerates within a compressed format. It can be done, no doubt about it, and yes, there might be a slight quality loss (although I can't tell), but the headache involved in fixing synch issues outweighs the slight benefits of audio quality...

The only time I could see the audio quality being such a big issue, is if you're ripping a DVD, and you've got DTS going on, and you wanna keep everything perfect...Yeah, now I'm getting excited...
Otherwise, somebody taking what was VCD audio, and adjusting the samplerate for DVD, via intermediate .wav files, should be good enough..

[pijetro]

Hey, look at the date and time of that post.. How ironic.....

[Dan East]

I'm encoding from a WAV (produced via DVD2AVI). After encoding with TMPGEnc I noticed that higher pitched sounds (particularly female voices) had a sort of buzzing sound or distortion to them. I assumed it was the combination of audio freq (44 kHz) and rate (180 kbs). After experimenting I determined the audio sounded perfect at 48 kHz, but found the hard way that most DVD players can't handle it. After some searching I found reports that TMPGEnc's audio encoder does a not-so-good-job, so I tried headAC3he with the same output settings and it sounds great. Hence my thoughts on TMPGEnc's audio encoding. Of course I would love to do it all in a single pass with TMPGEnc if at all possible. That saves me the extra encoding step and multiplexing.

Dan East

[pijetro]

I'm fascinated with DVD2AVI, but haven't had the chance to play with it. Isn't it possible to export just the audio as a wav file?? If it is, then converting the sample rate with Cool Edit shouldn't effect anything, especially if the source is clean. It's a shame that you're creating VCD's that have 48khz as a samplerate. You're lucky to have found a standalone that will play it at all..You probably know this, but DVD audio is 48khz, VCD and SVCD audio is 41khz....If you would be able to get your audio down to a 41khz samplerate cleanly, then you wouldn't have to hunt down anymore players....

Good luck!!!!!!!

[Dan East]

Oh, I'm not creating them at 48kHz anymore. That's why I'm using headAC3he to encode them at 44kHz at good quality. DVD2AVI does spit out a wav file. I'll have to look into using toolame to do the encoding within TMPGEnc to save the extra step.

Dan East