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pixelpusher
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Creating Varied Transparency Mask

Post by pixelpusher » 29 Jul 2020, 17:40

Hello all.
I am interested in figuring out how to take a grey scale image, and make it a mask maintaining the various levels of grey as various levels of transparency.
So black would be o% transparent and white would be 100% transparent.
I can't figure out a good approach to this.
The various key tools allow for filtering a range to a fully opaque mask, not what I want.
I want a variable matte, maintaining the variety of density driven by the greys.
Any direction appreciated.
Stay safe and well!
Casey

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slowtiger
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Re: Creating Varied Transparency Mask

Post by slowtiger » 29 Jul 2020, 17:58

The Scan cleaner would transfer a bw image into these transparencies, but TVP can't use this as a mask on a different layer the same way as it peserves alpha on the same layer.
TVP 10.0.18, Mac Pro Quadcore 3 GHz, 16 GB RAM, OS 10.11, QT 7.7.3

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ematecki
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Re: Creating Varied Transparency Mask

Post by ematecki » 30 Jul 2020, 06:27

Yes it can :)

You have to activate "Stencil" on the gray-level layer, and then it will only draw (in any layer) where there is already opacity in this layer.

Untitled.png
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Quicktime is DEAD. Get over it and move on !

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Hironori Takagi
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Re: Creating Varied Transparency Mask

Post by Hironori Takagi » 30 Jul 2020, 06:30

I'm interested in this issue and created a custom panel that behaves the same as the After Effects plugin "Unmult".
WhiteOnOff(e)_200730.png
Is your goal different from this?
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WhiteOnOff_190607.tvpx
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TVPaint 11.0.9, Windows10 Pro, DELL Precision M3800 / Mac OS 10.15, Apple Mac Pro(Late 2013)

pixelpusher
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Joined: 05 Nov 2013, 17:06

Re: Creating Varied Transparency Mask

Post by pixelpusher » 30 Jul 2020, 19:38

Yes, my goal is different.
I am interested in maintaining the full 256 steps of potential variation in transparency of a mask, (or alpha whichever you prefer) driven by the grey scale of the source image(s).
So were it a full color image, first step is a black and white conversion. No problem. Then a conversion to a variable density mask/alpha image based on the grey scale. 0% black = 100% transparent, 25% black = 75% transparent 50% black = 50% transparent 75% black = 25% transparent 100% black = 0% transparent, and every step in between these as well. Equivalent to a gradient mask/alpha driven by the image.
Thanks for the interest and feedback on this.
Scan Cleaner does not do this in my estimation. It is more like the color keying tools and isolates a range that then is the mask/alpha.

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ematecki
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Re: Creating Varied Transparency Mask

Post by ematecki » 30 Jul 2020, 21:18

Ok, I misunderstood...
Convert to B&W.
Then try the Luma Keyer with these values :
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Because of data validation, you have to input the 255s from right to left...
Quicktime is DEAD. Get over it and move on !

pixelpusher
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Joined: 05 Nov 2013, 17:06

Re: Creating Varied Transparency Mask

Post by pixelpusher » 31 Jul 2020, 15:59

Thanks ematecki!
This was a great solution to what I was trying to do!
I so appreciate your assist.
Be well and thank you!

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