Something wierd happening with VidCap audio

farss wrote on 7/31/2005, 5:17 PM
Having been up to the small hours of the morning capturing video and then done some trouble shooting on this problem all I can say is I'm not a happy chappy.
Using VidCap 50 to capture PAL DB from J30 here's what I'm finding.
The audio is ending up as 16/32K according to Vegas and SF, no wonder it sounds horrid during capture, VidCap sets the audio device at 48K! Switching project property to 32K at least means it plays back right from the T/L.
So thinking maybe the J30 is to blame and checking settings and manual and extensive Googling we ran some tests. Connected 1394 port of J30 to Miranda DV bridge. Playout tape and the bridge reports audio as 48K, as advertised, switch J30 to Channels 1/2/3/4 and as advertised according to DV Bridge audio changes to 32K. Conclusion, J30 works correctly.
So this leads to the obvious question, how the hell is Vegas able to convince the deck to output audio at 32K, or is it, is VidCap somehow managing to screw around with the audio, that'd not seem likely, it'd have to be resampling on the fly which I seriously doubt.
The only test I've yet to try is switching off DV Device control and doing a crash capture, maybe, just maybe something is odd in the command sequence that VidCap is sending to the deck. Again rather unlikely. Whatever this problem is I'd rate it as pretty serious and I've gone back and checked previous captures on another system from a J30 and they're the same oddball 16/32K audio.
Worse still I've got a suspicion this isn't just happening with the J30s as well, I seem to regulalry end up with 16/32K audio out of my DSR-11 from camera tapes out of cameras that can't even record 32K audio as far as I know.
I've lodged a support request but I'm hoping others can confirm this issue, up until now I always wondered why so many Vegas users don't use VidCap as I;d never had an issue with it, that's sure come back to bite me.
Bob.

Comments

Spot|DSE wrote on 7/31/2005, 8:56 PM
Bob, have you tried this with Scenelyzer? I rarely use this app, but on the odd occasion that I've had capture issues, it occasionally works, and helps me point a finger at Vegas or Avid, depending on what I"m capturing with. I've never seen VidCap change the sampling rate, but I've seen other oddities with various decks. You're sure the Miranda isn't doing something odd? Have you tried the Convergent in place of the Miranda? (I'm thinking you have a Convergent, yes?)
farss wrote on 8/1/2005, 12:49 AM
Firstly we're not capturing through the Miranda, we just hooked it up to confirm what the J30s output and as I said it confirmed that what comes out of the J30 is exactly what Sony say it should be. Clearly VidCap50.exe is resampling the audio to 32K and that's rather nasty.
At the advice of local support I tried capturing with V6.0b by starting VidCap from within Vegas with project properties confirmed as 16/48K and wonder of wonders we got 16/48K audio captured.

This is sort of good news, at least we can get working again but it does raise more questions than it answers.

I think a lot of us here have always been under the impression that VidCap simply transfers data from the tape bit for bit, clearly that's not entirely correct. I still haven't narrowed this down 100%, what I didn't have time to check is if VidCap60.exe started standalone captures correctly or if it needs some parameters that are passed from Vegas.

What I have confirmed just now is that no matter how I start VidCap50.exe, either from within a project or standalone I get 16/32K audio. As one more test I'm installing V6.0b on the PC we normally run V5.0 just to eliminate some oddity in the PC.

Stay posted, this is sure a wierd one.

Bob.
farss wrote on 8/1/2005, 1:51 AM
This just got wierder.
Installed V6.0b on the 'other' PC and wonder of wonders, it still captures the audio at 16/32K!!
Disable Deck COntrol and do a crash capture and we get 16/48K, clearly somehow the deck control commands are screwing something up.
Bob.
farss wrote on 8/1/2005, 5:51 AM
Just took your advice and SCL seems to capture just fine, audio all as it should be. Crash capturing with V6.0b also gives the correct result but that's no help as no TC, need to add burnt in TC and also go back and batch capture 4.2.2 once we have a rough EDL, no way can I afford enough disks for 20 hours of 4.2.2!
Oddly enough at very rare times VidCap gets it right, thought it might be F/wire 410 screwing things up but unplugging that didn't help either. Looks like another long night.
Bob.