Onlining. Is Uncompressed compressed?

J

JoPo

Member
I am just finishing editing some commercials and the client asked that we work with a specific Onlining House. They're completely rebuiding our edits from an Adrenaline and a FCP machine but to keep this short...they said that they would need the MXF files as part of the assets. I was told that even though the Avid reads the MXF files natively, when we exported to Uncompressed Quicktimes, they actually get compressed a bit. This was news to me. Is this true? Then would that be the same in FCP? Converting to Uncompressed QT's compressed them?
I was told that they would import the MXF files into Flame and then export to their DS and that would make a better finished product.
Any insight would be interesting. I've never had to jump hoops for onlining like I have to for these guys although they are nice guys.
jP
 
JoPo said:
I am just finishing editing some commercials and the client asked that we work with a specific Onlining House. They're completely rebuiding our edits from an Adrenaline and a FCP machine but to keep this short...they said that they would need the MXF files as part of the assets. I was told that even though the Avid reads the MXF files natively, when we exported to Uncompressed Quicktimes, they actually get compressed a bit. This was news to me. Is this true? Then would that be the same in FCP? Converting to Uncompressed QT's compressed them?
I was told that they would import the MXF files into Flame and then export to their DS and that would make a better finished product.
Any insight would be interesting. I've never had to jump hoops for onlining like I have to for these guys although they are nice guys.
jP
Click to expand...

Any way to talk directly to the Flame/DS editors ? They might have some insight for you or at least be able to tell you exactly what they're looking for.
 
I have spoken to the editors and what I wrote above is coming from them and I'm have no problems with the assets. I just wanted to know about the Uncompressed/compressed thing. Why would they call it "uncompressed" if it's actually compressed.
 
There is really nothing "uncompressed" about MXF files coming out of the HVX200 to begin with. They contain DVCPRO HD material, which is compressed right off the bat.

Try using 16 bit TIFF image sequences if your really that worried.
 
Ok. Thanks for the info. I'm still wondering though if converting the MXF (yes even if they are compressed by nature) files to UNcompressed QT's actually compresses it?
 
Nope... sorta... but...

You cannot really uncompress compressed material... Information lost through compression is lost forever, independently of which format you choose to eventually save your data in. So the conversion does not uncompress, it just saves the compressed data in an other data format... BUT

You can transcode data, not uncompress them,but you can gain some advantages from that, given specific scenarios.

Let's say that you record your material with an HVX to DVCPRO HD.

The "bad" carracteristics of DVCPRO (HD) is noisy darks. It's a codec thing. (Barry may not agree, and I know there are ways to better it, but I see it repeatedly in my own and others material, and it's a known thing from Panny as well...)
Let's say you have recorded your dark footy "overexposed" (that is not blown, but lighter than what you want the finished image to be).
Theoretically, you may be well off to transcode to uncompressed or prores before setting the final luma charracterristics, just because those codecs trets those scenarios beter than DVCPRO HD (... that doesn't come from a Varicam or a HPX 2000...)

The second scenario is when you're doing heavy comp'ing and/or colorcorrection.

Because if you have other material from better formats, why not keep the goodies for as long as you can?

That's sorta sums it up...

But, again:
Info lost at initial recording, will never come back.

Gunleik
 
I think they're just trying to eliminate the possibility that your guys would mess anything up. If they have the MXFs they know they have the originals.
 
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