Just tested a slew of Gamma adjustments (in both directions) in Squeeze 7 -- and it definitely doesn't seem like it's Gamma.
Also tested exporting 709 QT and using that as a source for compressions -- again -- and still no joy.
Can't figure out why Avid can export an H.264 that is in "unity" with the timeline -- but Squeeze cannot.
And I'd use Avid, but the quality level is terrible.
--- In Avid-L2@yahoogroups.com, "blafarm" <blafarm@...> wrote:
>
> 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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