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Apple Compressor edge artifacts

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Bob Cole
Apple Compressor edge artifacts
on Jan 22, 2010 at 10:29:59 pm

I made a Quicktime movie (Kona umcompressed 8 bit SD) of a ProRes 422LT HD timeline, & put the Quicktime movie into its own new sequence. I exported both the original ProRes HD file and the SD file to Compressor (DVD high quality 150 minutes).

My purpose was to find out which file (original HD or downsized SD) looked better in the final DVD (btw, SD looks better at least in Compressor). But what I found instead was erratic green flashes on the bottom 1-4 pixels of the both compressed files. These artifacts are not in the original.

Is this due to the fact that I used ProRes422 LT?

I understand that these artifacts would not be visible on a traditional television, but nowadays with people popping DVDs into their laptops, I like to make sure the entire frame is clean. I also understand that I could use cropping in Compressor, but I'd rather not.

My alternative workflow is to live play out from the Mac to a HP workstation that is equipped with a Digital Rapids card. That works fine.

Thanks!

Bob C


Snow Leopard
MacPro dual-core
FCS3 (FCP 7.01, Compressor 3.5.1)


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Daniel Low
Re: Apple Compressor edge artifacts
on Jan 23, 2010 at 10:24:51 pm

[Bob Cole] "Is this due to the fact that I used ProRes422 LT? "

No, it's likely just an anomaly in the scaling process, chooses another scaling setting and it might disappear.



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Bob Cole
Re: Apple Compressor edge artifacts
on Jan 24, 2010 at 5:51:23 am

[Daniel Low] "No, it's likely just an anomaly in the scaling process, chooses another scaling setting and it might disappear."

But for the original, I used two versions of the file, one at SD and the other at HD size. Both had similar artifacts: bright solid-colored blocks of pixels.


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