DXV3 & AE masks bug?

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Asthettic
Met Resolume in a bar the other day
Posts: 6
Joined: Wed Mar 23, 2016 14:23

Re: DXV3 & AE masks bug?

Post by Asthettic »

@ Oaktown
Super thank you :)

The 'high' file works perfectly. It says DXV3 and in an alpha surrounding.
The 'normal' file has the same weirdness. In the preview it has a black background & when I trigger it the background is transparant. When I preview whilst it's triggered/playing, the black background is gone.

Also, I don't know the footage very well, but the preview is a line instead of text, is that normal?

I was looking at the clip properties & now noticed that even on your clips the alpha type in the video properties for the clip is on premultiplied! Putting it to straight there does make a difference on your clips & on some of mine (not all of them....)

Hope these screenshots are clear.
Attachments
clips properties adjusted to straight
clips properties adjusted to straight
clip propperties as orginally loaded
clip propperties as orginally loaded
text = line in preview
text = line in preview
alpha layer = black in preview
alpha layer = black in preview

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Oaktown
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Joined: Tue May 08, 2012 15:19
Location: Oakland, CA

Re: DXV3 & AE masks bug?

Post by Oaktown »

This article may help you understand what straight and pre-multiplied alpha mattes are and how they get interpreted: http://dvd-hq.info/alpha_matting.php.

I think pre-multiplied is the default mode in Arena so whenever your alpha channel doesn't behave as expected, changing the mode should be the first thing one does.

The footage I shared with you was encoded as straight alpha matte so if you select pre-multiplied it gives an opaque text box because it doesn't have the right combination of RGB & A information. Whenever I create content with an alpha channel, I personally always use straight alpha matting to avoid as much as possible losing color information as the footage gets re-rendered downstream from my studio.

Asthettic
Met Resolume in a bar the other day
Posts: 6
Joined: Wed Mar 23, 2016 14:23

Re: DXV3 & AE masks bug?

Post by Asthettic »

Thnx everybody!

So I think I understand alpha even better after reading this.
My next thing is to check ALL my files & settings. In output and in resolume.
Gonna take some time this morning :)
Hope my next post is a fullscreen shot of my UI where everything is right & working :D

Asthettic
Met Resolume in a bar the other day
Posts: 6
Joined: Wed Mar 23, 2016 14:23

Re: DXV3 & AE masks bug?

Post by Asthettic »

As promissed some fullscreen shots
Big thank you again, understanding alpha better helped loads; looks like all is working ok now.

I exported my clips alpha 'straight'.
then manually, per clip, adjusted the clip setting to straight. It seems to be premultiplied as default (maybe a nice option for the defaults preferences in an update? ;) )
In Preview alpha is still black , but the clip triggers fine now
export straight, clip setting straight. preview = black, trigger = fine
export straight, clip setting straight. preview = black, trigger = fine
greenscreen (masked out in photoshop) straight-straight : no problem
greenscreen (masked out in photoshop) straight-straight : no problem
btw when my clip is exported straight & left on the default setting premultiplied, I still see the part that I had masked out completly in Ae. Same goes for the greenscreen & random white bits that were never there before export or outside of resolume.....
Without it being an issue, still finding that kind of hard to understand..?
export: alpha straight; default setting clip = premultiplied. Strange to see what I masked out came back
export: alpha straight; default setting clip = premultiplied. Strange to see what I masked out came back
same file but default clip setting still in premultiplied (hello greenscren & white debris?)
same file but default clip setting still in premultiplied (hello greenscren & white debris?)
Thank a lot for all you comments & help guys!

serch54
Met Resolume in a bar the other day
Posts: 3
Joined: Thu Sep 20, 2012 04:42

Re: DXV3 & AE masks bug?

Post by serch54 »

Thank you Oaktown! your video solved my problem. I've been using the same DXV3 preset for as long as I've had it, and was always getting my Alpha channel. Somehow that setting got switched in the codec and I didn't know where to look. cheers!

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