View Full Version : Playback stuters with unknown QT codec after import!


Tony Pham
January 3rd, 2007, 04:16 AM
Hi everyone,

I just got a self-contained QT file from my boss and I'm unsure about what to do. I have a few questions and problems:


1. We're not sure what the codec was used for this file. Is there way to find out either it's DV or DV50 or HD so we can set the project type accordingly when creating a new project with Avid?


2. I imported this file into AE 7 and here's what I got when I highlighted the clip:

720x486 (0.90)

29.97 fps

Millions of Colors

YUV422 codec

48.000 kHz / 16 bit / Stereo


What project type should I set when I create a new project with Avid to import this file? Should I import the file as DV50 or 1:1?


3. When I tried to import this file into a 30i project type with OMF 411, the playback get stutered inside Avid. Here's the tricky part! It only stuters when I have Mojo component output selected. When I disable Mojo component output (by clicking on the DNA button on the top right of the timeline) and use firewire output from Mojo only, the same clip doesn't get stuter on playback. The stuter is random and I tried the exact same clip and it gives the smooth playback when I diabled Mojo component output. Any ideas? This is scary because I don't want to start a project (this is a long project) and in the end realize that I can't get smooth output.


P.S: Aside from the above information, this QT file is 80 gig for about 1 hour and 15 minutes. This is way bigger than a normal DV QT. Also, I'm using Avid 5.6.2 with Mojo SDI.


I really need help with this. Please advise. Thank you so much!

Alister Chapman
January 4th, 2007, 12:56 PM
The YUV 422 codec is an uncompressed codec, which why your file is so big, and it will be stretching your system, especially you hard drive/raid array. Switch in the mojo and as well as handling a massive file with very high data rate you are also asking the system to do an on the fly conversion. Unless you have a really good PC with a raid array I doubt very much you will be able to get stutter free output to your mojo.

The choice of project will depend on what your final output is going to be.

Tony Pham
January 4th, 2007, 03:26 PM
Thanks, Alister!