Resolume Forum

@ 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.

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.

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

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 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..? Thank a lot for all you comments & help guys!

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!