Chaps,
I recently flung a Matrox RTX 100 Xtreme Pro into my PC.
PC spec:
2.6ghz processor
2gb RAM (beefy)
3x200gb hard drives (Maxtor, 7200rpm jobbies)
Geoforce 5600 video card
Bog standard sound card
All running under the glorious wizardry that is Windows XP (running SP2).
Now! Here's the problem:
I'm breaking the card in by editing down a recent dance contest which we shot with three cameras. I'm using Premiere Pro which naturally came bundled with the card. At first things were fine. I captured the first 50 minute act in a single file (so three files altogether for each camera) and edited to the original CD track which is identical to the track played on the night.
The further I get through, the more the video and audio are getting out-of-synch with the CD.
By the time I got to the final 10 minutes the CD track was coming in LONGER by almost 19 seconds.
It was driving me mad while I was editing as the music kept slipping out of synch with what the cameras had recorded.
I went back and recaptured a single song (approx 5 minutes long) and the CD track is EXACTLY on time.
So I captured the full 50 minutes of the first act again using a standard firewire card and Premiere 6.5 and it's spot on perfect with the CDs.
So does anyone know whether it's the Matrox card or Premiere Pro that's encoding the video at a weird rate? Or a combination of both?
Good luck, dears.
Matt.
capture the audio.( it will probably capture @ 44.1khz)
convert to 48khz
now put it on the timeline.
bet it is a little bit better now.
I've tried various combinations as that was my first guess.
The CDs were captured at 44khz (roughly) and the project was 48khz. I thought that might be the problem.
However, it didn't change anything.
Are you suggesting I capture the video first, then capture the audio again? The video is slower than the CD track as well. It's the whole captured file that's slower so how would that help?
I would have audio and video which weren't synched.
(sorry - a bit confused)
ok .
capture the audio from the cd as 48KHZ audio or convert it from 44.1 to 48khz.
you say the cd audio tallies with the audio on the video
I went back and recaptured a single song (approx 5 minutes long) and the CD track is EXACTLY on time.
so use each cd track seperately , starting at the beginning of each 'video' version.
that way the 48khz audio should match the video.
Matt,
I think there is a function called "audi drift" which you can find on the Matrox site and also page 62 in the RTX100 handbook. Have a look over there and search for "audio drift" and see if anyone can help.
http://forum2.matrox.com/cgi-bin/rtx100/ultimatebb.cgi
The CD only tallies with the captured footage when I capture it in little bits.
If I capture the entire 50 minute sequence the CD audio is waaaay off.
That's essentially the problem.
However, if I capture through standard Firewire and not the Matrox card it's fine. The full 50 minute video clip and the CD audio tracks match up throughout.
I know the obvious answer is: Don't use the Matrox card to capture. But I'm not overjoyed at yanking firewire leads just to capture.
Originally posted by PP:
Matt,I think there is a function called "audi drift" which you can find on the Matrox site and also page 62 in the RTX100 handbook. Have a look over there and search for "audio drift" and see if anyone can help.
http://forum2.matrox.com/cgi-bin/rtx100/ultimatebb.cgi
Now you mention it - that rings a bell from when I was installing Matrox tools.
I'll get back to you on that. Cheers :D
Surely if it was a 44khz>48khz problem, the audio conforming which happens in Premiere Pro would have sorted it out anyway?
Pass .....
I always transcode to 48khz using cooledit/audition before loading a cd track into any nle.
i found out the hard way what a PITA it could be doing it any other way.
In fact the audio conforming in Premiere Pro would appear to be the shiteful problem here.
As suggested it's highly beneficial to convert to 48k in Audition rather than let Premiere sort it out as I found out on my current project.
Still not solved the problem with the Dance one though :(
I have found that the Matrox card has a habit of dropping frames but not reporting them as dropped. I keep finding little 3-4 second chunks missing from my captured video. The clips are fine on the original tape.
I'd have thought a Matrox card, at the price it is, would be able to capture 45 minutes of continuous video without dropping frames (and before you say it - the PC is fine).
I think the "Audio Drift" function is only used for the phono (analogue) connections.