Thanks for your response Dom.
I just determined the following:
1. Squeeze seems to want an Avid exported 709 file -- and not RGB
2. Using 709 - I can apply a Squeeze -13 gamma shift - and pretty much nail the gamma. I have tested this by re-importing the resulting H.264 file (Avid import set to 0-255) and comparing it to the source shot on my timeline -- both visually and with BMD Ultrascope out of my MojoDX.
3. At that point, I need to add +3 of Squeeze saturation to resolve the chroma differences between the two.
Based on those findings, does that change your opinion of the possible necessity of uninstalling FFDShow (which, for the record, I did install with Squeeze)?
And can you please tell me why removing that app might change the outcome -- as I'm using Squeeze's MainConcept H.264 codec?
Thanks
--- In Avid-L2@yahoogroups.com, "Dom Q. Silverio" <domqsilverio@...> wrote:
>
> If you installed it with Squeeze, try uninstalling the FFDShow codecs.
>
>
>
> On 10/7/2011 7:03 PM, blafarm wrote:
> > 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
> >>>>
> >>>>
> >>>>
> >>>>
> >
> >
> >
> > ------------------------------------
> >
> > Search the official Complete Avid-L archives at: http://archives.bengrosser.com/avid/
> > Yahoo! Groups Links
> >
> >
> >
> >
>
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