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Alpha Channels

Posted: Mon Jan 16, 2012 3:20 pm
by scaryxpuppy
I wonder if anyone can help.......

I am looking at a simple MAP where I am trying to project onto a car using VDMX and MADMAPPER which is seemingly straightforward - basically, I have just created a lot of masking around the car.

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However, i then need to project a different image onto the door!

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Image 02
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If I use the masking in MADMAPPER, it adds BLACK around my mask, so I have created a mask directly in VDMX and am sending a preset masked video through that is the right shape (did this by creating a mask in MADMAPPER, inverted to a solid white shape and then took a screen grab - I then used this as a layer mask in VDMX)

When I input this door video from VDMX, the problem is I can not seem to get the IGNORE ALPHA function to work ! - it still keeps the black around the edges

If i use the ADD function, it seems to merge them!

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Image 03
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Is there a workaround that anyone can think of??

Many thanks

PHIL

Re: Alpha Channels

Posted: Mon Jan 16, 2012 3:33 pm
by scaryxpuppy
....... Or maybe VDMX is not the best package to use??? Its just I like it for other applications, but if anyone knows of a better way of doing this idea then i'm open to any suggestions!

PHIL

Re: Alpha Channels

Posted: Wed Jan 18, 2012 2:57 am
by pele2010
hi ,

i think you need either an app like AE to do so.

Or someone that wrote a module for this kind of task.

Maybe QC can draw a hole in a video projection, biut i couldn“t find a composition.

Anybody experience with this ?

thanxs

pele2010

Re: Alpha Channels

Posted: Wed Jan 18, 2012 11:53 am
by franz
Ignore Alpha will ... ignore alpha, rendering it as black. This is not what you want.
Add will addition the pixel values, so adding black (0,0,0) will do nothing. This is not what you want.

Over will interpret the alpha values as transparent pixels. This is probably what you want.