video as mask

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VjLuper
Is taking Resolume on a second date
Posts: 31
Joined: Mon Apr 12, 2010 10:48

video as mask

Post by VjLuper »

hey, silly question:
if I have a video rendered with alpha channel (DXV) may I use it as a mask?
or, its possible to use a normal B/W video as mask for other video?

pfelberg
Wants to marry Resolume, and Resolume said "yes!"
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Re: video as mask

Post by pfelberg »

Yes,
You can disable the Alpha on the clip properties RGB "(A)". Then, you can use LumaKey or Lumakey 1 blend modes to use white or black as a video mask to all video bellow.

Paulo

Joris
Doesn't Know Jack about VJ'ing or Software Development and Mostly Just Gets Coffee for Everyone
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Re: video as mask

Post by Joris »

I think VJLuper is asking about the exact same thing as what you call 'parenting', Paulo.

The most used term for this is layer mask or a track matte. Usually the luma or alpha channel of one layer are used to mask areas of the other layer. Parenting usually refers making an object or layer follow the movement of another object or layer.

Neither of those are currently possible in Resolume. Track mattes are on the radar though.

VjLuper
Is taking Resolume on a second date
Posts: 31
Joined: Mon Apr 12, 2010 10:48

Re: video as mask

Post by VjLuper »

yes parenting is a way, or also the possibility of put a video where you usually put the (PNG) mask!

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subpixel
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Re: video as mask

Post by subpixel »

It *IS* possible to do this in Resolume. You need at least 5 layers to do it (including one "background" content layer).

1. Matte shape layer(s). Start with ARGB content, or use an effect such as Auto Mask (which maps luma to the alpha channel) or the Luma as Alpha blend mode (requires more than one layer).
2. Content layer (use Multiply or similalr to cut out to the shape of the matte).
3. Layer Router layer. This is a kind of "flatten" layer. Set the source to "Composition" (which is your cut out content from the previous layers).
4. Background layer(s). Whatever you want the cut-out content to float above. Note that you probably want to make sure that you have something "solid" so your matte setup layers below don't show through. You can stick in a solid black layer for safety if you like.
5. Layer Router layer. This is the overlay! Set the source to the other Layer Router layer (whatever "3" is).

Magic!

-subpixel

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