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Robert Longwell
Uncompressed Error in Engine
on Aug 29, 2007 at 2:05:40 pm

Ok I'm stumped.

Occasionally we receive an uncompressed QT file (QT reports the codec as "none"). If I encoded this file on my 8 Core Mac Pro in Episode Pro the encodings come out just fine. However if I drop this same file into Episode Engine the file comes out very distorted. The entire image is on a slant, yes, a slant.

The codecs on my Mac Pro are identical to the Engine nodes, QT versions are the same as well. Oddly enough if I open up this uncompressed QT file in QT on the nodes the video is a white screen, which usually means a missing codec. But uncompressed is just that, it has no codec in theory.

Since my codecs are dupliated across all the Macs, QT versions are identical, I don't know what else to do. I'm stumped!

Robert Longwell


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Jack Arky
Re: Uncompressed Error in Engine
on Aug 29, 2007 at 3:44:50 pm

Robert,

I've seen some of this behavior on occasion too. I once saw the slant issue out of Engine and assumed it was a communication error with our shared storage as we use ref files. I'll have to go back and see if I can piece together what the source format was as well as destination. It wasn't too long ago that I saw this.

Regarding the white screen, aside from missing codecs, I've seen this behavior when the file is coming from a PC platform, usually with uncompressed avi. Do you know if your source was output on a PC? Do you know if the QT version from the source is identical to yours?

Jack



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Jack Arky
Re: Uncompressed Error in Engine
on Aug 29, 2007 at 7:42:17 pm

I was able to locate the source that caused the issue. Looking at the info in QT, Format is None, 720x480, Millions + ; audio is 16 bit (Little Endian), Stereo, 44.1khz. File was output from a PC.

Perhaps the Alpha channel was the source of the problem in our case? Don't know why the editor output it with the alpha. I also don't know why they output the audio at 44.1 but that's another issue.

Trouble is, I've tried to reproduce the problem in Engine and can't. We were outputting to wmv and 3gp (mpeg4) formats. Saw video askew and also had a greenish cast.

Bit of a head scratcher now. We were able to reproduce the problem at the time a few weeks back. Not now. Gremlins.



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Jack Arky
Re: Uncompressed Error in Engine
on Aug 29, 2007 at 8:32:07 pm

Okay. NOW I've been able to reproduce the problem.

We use an automated system that generates ref files using QT for Java on a PC platform. All the ref file does is point back to the asset on the shared storage system. This keeps us from having to copy large files between systems. We do this every day with hundreds of files and rarely have an issue.

If I MOVE the mov file to Engine, despite the odd format settings, it encodes no problem. When I use our automated system and generate a ref file pointing back to the mov on shared storage: in the case of the wmv output, slanted video; in the case of the 3gp file, slanted video and a greenish cast. As I said, the original mov is rendered on a PC, uncompressed with an alpha channel. I can't say as I understand why this happens, but at least I can reproduce the problem.

Robert, I don't know if any of this bears any resemblance to the issues you're having.



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Robert Longwell
Re: Uncompressed Error in Engine
on Aug 29, 2007 at 9:05:52 pm

Hmmm, it sounds similar to our system. We also generate some QT refs from the original files before dropping into Engine, also from a PC.

I think you may be onto something here. Once I bypassed the QT Ref step on the PC and encoded this manually on the the Engine it came out just fine.

Robert Longwell


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Jack Arky
Re: Uncompressed Error in Engine
on Aug 29, 2007 at 9:17:13 pm

REALLY interesting. So I just took the ref that our system generates and copied it over to the Engine controller manually. Took the ref and dropped it into an Engine watchfolder and it came out with the slant. Opened the ref in QT on that system and it looks just fine. Exported from the ref on that system in QT and it exported fine. Looks like it's time to pass this one on to the guys in Sweden.



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Robert Longwell
Re: Uncompressed Error in Engine
on Aug 29, 2007 at 9:23:36 pm

I know the new release is supposed to address some Ref errors, not sure if this is one of them. Last I heard the new release is slated for release around IBC.

Robert Longwell


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