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Ugly borders in avi and mpeg

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Lisa Ganseblume
Ugly borders in avi and mpeg
on Nov 5, 2010 at 11:20:35 am

Hi,

I'm just trying to render an animation which I'm asked to deliver in uncompressed avi or mpeg (or at least as uncompressed as possible).

As I'm on a mac avi is out anyway for rendering it directly from after effects and a direct rendering to mpeg doesn't make any sense as after effects only supports single pass rendering and as far as I know mpeg looks way better after double-pass-rendering. Moreover I'm using a special format, so I can't go over Premiere to render it.

So I think the easiest way is to render it as a Quicktime Animation Codec File (Keyframe every frame - size doesn't matter with this one) and then covert it.

The video looks perfekt in quicktime but whenever I'm trying to convert to avi or mpeg - using media encoder or mpeg streamclip - I do have crappy brownish borders appearing around the borders where red and green meets. The same happens if I render mpeg directly from ae?

Why is this? And has anyone found a way to avoid this?


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Chris Blair
Re: Ugly borders in avi and mpeg
on Nov 6, 2010 at 4:34:51 pm

If you're converting from the Quicktime animation codec to an uncompressed AVI, the only thing occuring is a transcode from one format to another. There is NO compression occurring.

If you're converting to MPEG, you ARE compressing and we'd need to know what type of MPEG, MPEG2? MP4? Also, what codec are you using?

You would want to make sure you're just passing through the pixel dimensions, frame rate, bit depth etc. of the file when you convert it. Otherwise, you should not be seeing any sort of degration going to uncompressed AVI. You would see some degradation going to MPEG2 or MP4, but if your data rate is set high enough, it would be virtually imperceptible to the eye.

Obviously, going to uncompressed AVI is the best choice if file size is no concern.

To give you more specific help we'd need to know all the specs of your original render, and the settings you're using in your export.

Also, if you're referring to Adobe Media Encoder when you mention "media encoder"....it sucks royally. It has so many quirks and bugs in it that in my opinion it's unusuable in a professional environment. Others would dispute that, but we gave up on it and moved on to more robust encoding tools.

Chris Blair
Magnetic Image, Inc.
Evansville, IN
http://www.videomi.com
Read our blog http://www.videomi.com/blog


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Daniel Low
Re: Ugly borders in avi and mpeg
on Nov 14, 2010 at 10:58:10 pm

Keep in mind that the Animation codec is only lossless when the setting is set to "Best" or 100% quality. Holds an 8-bit alpha channel but is limited to 32-bit rendering. This codec does encode and decode quickly though.

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