I guess.....An effect. Maybe stacking order of an effect? Head over and clck the FX switch on the effects one at a time and see if that cures it.
Looks like an OpneGL buffer artifact, either from the fast preview stuff or an OpenGL-driven effect like MB Looks or whatever. Update your graphics driver.
from your screencap it looks like theres no effects applid but the footage is mpeg4.
try transcoding that clip to prores or dnxhd or some other format.
its possible that the footage is trying to build the image from multiple frames due to the compression and thats causing the error
The project was started in AE CS5.5 on my Macbook Pro, but as it got more complex, it became unwieldy to work with on the less powerful machine. So I transferred it to my work computer, which is running CS6 on Windows 7 with NVIDIA Quadro 4000 and GPU acceleration. I know, that probably complicates things significantly. It should also be noted that the computer is brand new and this is the first AE project I've run on it.
As expected when jumping up to a newer version, AE generated a new project file with a copy of the existing project. Everything seemed to transfer correctly, but only after I'd been working a few hours did these artifacts begin to appear.
I do not have any third-party plug-ins installed that did not come with CS6.
I haven't been able to find anything in AE concerning OpenGL, so I'm not sure if that might be responsible.
The footage is 1080 XDCam 60i in an mp4 container.
Hope this helps, and thank you very much.
It's probably the mp4 decoding that is causing the problem. Make sure that everything including QT is up to date.
So AE, Premiere, QT and the graphics card are all up to date. Still no luck.
Did a test render, and the glitch carries through to the output files as well.
I'm going to try bringing the footage into Premiere, pre-cutting this section and then bringing it in through Dynamic Link. Hopefully it'll be an easy fix for this particular segment, but there's still the rest of the project.