Are you sure it's actually in the video file and not just some kind of display anomaly? Have you tried making a test file, which appears to have become pixelated and interlaced, then seeing if it looks that way on another system?
I know there were people complaining about the state of nVidia drivers for Lion, so it's something to consider and also quick and easy to rule out.
Whenever I import perfect quality MP4 Files to iMovie they always become pixelated or interlaced, no matter how much i play with the setting. This problem just recently occurred when switching to lion, I have been editing on previous OS for a long time now without problems like this. Is this a problem with Lion or what? I have tried the deinterlace option with both iMovie and MPEG Streamclip and they did little to nothing. Thanks in advance for anyone who helps ![]()

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