Thanks for your response.
The source files are Cannon 5D imported as RGB.
The Avid project is YCbCR 709.
And I exported all of the QT's as RGB.
At first I thought it might be gamma.
Then I thought it might 0-255 vs. 16-235 mapping.
My Squeeze presets are "known quantities".
And I realize I could get into the filter thing...
But I was hoping to find the [possible] error of my ways.
And just nail this problem without a lot of trial and error.
--- In Avid-L2@yahoogroups.com, Jeff Cook <jeff@...> wrote:
>
> Not sure about Squeeze, but a problem with Cleaner used to be that
> anybody could overwrite the presets without necessarily knowing it, so
> check that you're not using altered settings.
>
> Otherwise, and unless it's a bug, can you add a video filter inside
> Squeeze and get good levels out that way? Only other thing that occurs
> just now is, are you sure it's the black levels and not a gamma/gray
> levels issue?
>
> --
> Jeff Cook
> jeff@...
> 703-980-1104 (cell)
>
> CookStudios.com
> Freelance Video Editing
> Washington DC & Portable
>
>
> Quoting blafarm <blafarm@...>:
>
> > Every H.264 file we create in Sorenson Squeeze 7 (PC) has elevated
> > black levels and reduced contrast. If I didn't know better I would
> > have thought it was a RGB vs. 709 issue -- but I think we've
> > disproved that.
> >
> > We have exported test files from Avid (PC) using three different
> > types of uncompressed QuickTime RGB (0-255) files -- Same as Source,
> > Avid Codecs and Avid 1:1x.
> >
> > And to check them for "unity" -- we re-imported them back into Avid
> > as RGB -- and they match perfectly with the timeline.
> >
> > Then we imported those uncompressed QuickTime files into Squeeze and
> > compressed them using three different types of H.264 codecs --
> > MainConcept, Apple and Sorenson.
> >
> > We have viewed all of these compressed files in QuickTime, Windows
> > Media Player, VLC, Firefox, Chrome and Internet Explorer -- and they
> > all have the same black and contrast problem.
> >
> > The we imported all of the H.264 files back into Avid as RGB -- and
> > they exhibit the exact same problem -- and do not match the timeline.
> >
> > Finally, we exported an H.264 file directly out of Avid -- which I
> > believe uses QuickTime codecs -- and the video levels are fine. And
> > then we re-imported that Avid H.264 file back into Avid as RGB --
> > and the levels match the timeline perfectly.
> >
> > I realize H.264 colorspace is different -- but the black level and
> > contrast differences we are seeing are significant. More confusing
> > -- is that the Avid H.264 export matches the timeline perfectly.
> >
> > And, lastly, the "Black Normalization to 16" checkbox in Squeeze 7
> > -- has had absolutely no affect in any of our tests.
> >
> > Anyone else see this problem -- or have a solution?
> >
> > Thanks in advance.
> >
> >
> >
> > ------------------------------------
> >
> > Search the official Complete Avid-L archives at:
> > http://archives.bengrosser.com/avid/
> > Yahoo! Groups Links
> >
> >
> >
> >
>
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