I think generally QuickTime, thus Squeeze in this case, prefers RGB.
On 10/7/2011 8:38 PM, blafarm wrote:
> Thanks for that explanation.
>
> Is it your opinion, that Squeeze prefers 709 over RGB?
>
> Or have I just lucked-into a group of settings that finally allows me to see unity between the source file in my Avid timeline -- and the H.264 file created in Squeeze with my gamma and saturation tweeks?
>
>
>
>
>
> --- In Avid-L2@yahoogroups.com, "Dom Q. Silverio"<domqsilverio@...> wrote:
>> 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
>>>
>>>
>>>
>>>
>
>
>
> ------------------------------------
>
> Search the official Complete Avid-L archives at: http://archives.bengrosser.com/avid/
> Yahoo! Groups Links
>
>
>
>
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