FFDShow is a set of codecs. Normally it should not interfere with the
decoding "normal" QT codecs like Avid as Squeeze usually use it for
other formats like XiVD and such. But I did come across your problem and
one of the steps I took was removing the FFDshow codecs.
Considering your recent post, I don't think FFDshow is the culprit. I
think this is just another QT app that cannot interpret the color space
information correctly (again). I think this is one of the reasons why
even Apple has given up on QT 7 (though QT X is not perfect either).
On 10/7/2011 8:22 PM, blafarm wrote:
> 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
>>>
>>>
>>>
>>>
>
>
>
> ------------------------------------
>
> Search the official Complete Avid-L archives at: http://archives.bengrosser.com/avid/
> Yahoo! Groups Links
>
>
>
>
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