Color Black not showing in graphics rendered with Alpha

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soentjie
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Color Black not showing in graphics rendered with Alpha

Post by soentjie » Thu Nov 09, 2017 18:34

I rendered a bunch graphics from After Effects, the color black is part of the design and need to show but in Resolume it looks like the black is also keyed out or unmalted.For example I have a logo on a black circle the logo will be the top layer on a red background (bottom layer). THe black doesn't show up

I rendered out as DXV codec with alpha, when I bring it back in AE there is definitely an alpha so that is not the issue, resolume also confirmed that the video clip has an alpha.
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Alpha Color black issue
Alpha Color black issue

Zoltán
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Re: Color Black not showing in graphics rendered with Alpha

Post by Zoltán » Thu Nov 09, 2017 18:52

Try setting the layer's blend mode to alpha and 100% opacity.
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gesp
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Re: Color Black not showing in graphics rendered with Alpha

Post by gesp » Fri Nov 17, 2017 17:45

I have the same problem here.. I already export in "Rgb" "alpha" "rgb+alpha" and in resolume i already try "add" "luma"

Can someone help me?

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Oaktown
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Re: Color Black not showing in graphics rendered with Alpha

Post by Oaktown » Fri Nov 17, 2017 18:13

Probably a straight vs pre-multiplied issue!

Resolume defaults to pre-multiplied. You need to understand the difference between straight and pre-multiplied so take a look at this post (and thread) to understand matting better.

Also, make sure you render your alpha files in maximum depth in 24+8 bit (8-bpc + alpha).

If you're having issues with the alpha channel with DXV3, you might want to take a look at this older thread.

gesp
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Re: Color Black not showing in graphics rendered with Alpha

Post by gesp » Fri Nov 17, 2017 20:01

I still don't understanding how to project a black image, i will explain exacly what is happening,
I have a composition in after effects with a single image and i export that with "quicktime" and "dxv3" with maximum quality, exacly you did in your video tutorial. Then i insert it in resolume and then i set alpha type to straight. And doesn't shows my black symbol. I've downloaded your video test and everything is ok, but with mine no..
Help me please

I've uploaded a print.

https://imgur.com/a/qazOr

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Oaktown
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Re: Color Black not showing in graphics rendered with Alpha

Post by Oaktown » Fri Nov 17, 2017 20:17

You can't project a black image because black is the absence of light.

So, are you talking about using a mask for other content?

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Oaktown
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Re: Color Black not showing in graphics rendered with Alpha

Post by Oaktown » Fri Nov 17, 2017 20:19

Take your L1C6 clip, move it to L2C6 and add a color clip below it for you to see the black outline.

Flaket
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Re: Color Black not showing in graphics rendered with Alpha

Post by Flaket » Sat Nov 18, 2017 00:50

gesp wrote:I still don't understanding how to project a black image, i will explain exacly what is happening,
I have a composition in after effects with a single image and i export that with "quicktime" and "dxv3" with maximum quality, exacly you did in your video tutorial. Then i insert it in resolume and then i set alpha type to straight. And doesn't shows my black symbol. I've downloaded your video test and everything is ok, but with mine no..
Help me please

I've uploaded a print.

https://imgur.com/a/qazOr
Hy,

Did you create a black solid on After effect or did you just applied a mask on a background?

It' not because it's black in after effect that means it will be black rendered, specially if you go with alpha channel.

To be sure that black will be rendered as black and not alpha, try to change the setting of your composition in after effect and change the black background with a colored one. Everything who'll have have the same color as the one you choosed as background will be rendered as an alpha channel.

gesp
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Re: Color Black not showing in graphics rendered with Alpha

Post by gesp » Mon Nov 20, 2017 10:20

I'll test with your tips. I'll tell the result soon. Thank you to everyone.

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subpixel
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Re: Color Black not showing in graphics rendered with Alpha

Post by subpixel » Wed Nov 22, 2017 16:50

gesp wrote:I have the same problem here.. I already export in "Rgb" "alpha" "rgb+alpha" and in resolume i already try "add" "luma"

Can someone help me?
Set your layer's blend mode to Alpha and opacity to 100%.

Although most blend modes work out the same as "Alpha" when set to 100%, you should consider that it doesn't make sense to "add black" (you are adding zero to the red, green and blue values), and the luma value of black is zero, so using Luma Key blend mode will make it disappear.

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