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EricChadwick
08-28-2003, 03:18 PM
It has been a long time since I've used Video Post, so I've forgotten just how this is supposed to work. Can't figure it out via the docs nor the tutorials either.

I want to composite a 32bit TGA file on top of my Scene and some Lens Effect filters. But the alpha is always ignored, and it just becomes a solid image covering the scene/glows. How the heck do I turn the alpha on?

>Scene Event: Camera1
>Filter Event: Lens Effects Glow
>Filter Event: Lens Effects Flare
>Image Input Event: MyImageWithAlpha.TGA
>Image Output Event: MyOutputImage.TIF

I also tried this, but to no avail:

>Scene Event: Camera1
>Filter Event: Lens Effects Glow
>Image Layer Event: Alpha Compositor
-->Filter Event: Lens Effects Flare
-->Image Input Event: MyImageWithAlpha.TGA
>Image Output Event: MyOutputImage.TIF

Anyone familiar with Video Post? This has got to be something simple, which is really the whole reason I'm using VP instead of AfterEffects or Photoshop. I just want to see the composited results while I tweak the Lens Effects filters...
Clanger
08-28-2003, 04:21 PM
Can you get the alpha without glow to work?
I'e select background pic and forground pic with alpha, then choose 'apha compositor'
With this does the top pic get cut out?
Clanger
08-28-2003, 04:46 PM
This worked with glow

VP cue:
Clanger
08-28-2003, 04:50 PM
Filter settings, make sure you use the bitmap with alpha as a mask:
Clanger
08-28-2003, 04:53 PM
Glow settings:
Clanger
08-28-2003, 04:54 PM
Result, do you think I'll get it into Expose 2?
EricChadwick
08-28-2003, 04:56 PM
The compositing order I'm trying to get is this, bottom to top:

Camera01 (on bottom)
Glow
Flare
Image with Alpha (on top)

The image is basically a log to superimpose. I need to make sure it isn't glowed or flared.

I tried using an Alpha Compositor, but it only let me do this...

>Image Layer Event: Alpha Compositor
-->Image Input Event: MyImageWithAlpha.TGA
-->Scene Event: Camera1
>Filter Event: Lens Effects Glow
>Filter Event: Lens Effects Flare
>Image Output Event: MyOutputImage.TIF

...which meant the image and the scene were alpha-composited, but then the whole thing was glowed and flared. I just want to alpha-composite an image on top of everything else. Should be easy... right? Strange...
Clanger
08-28-2003, 05:31 PM
I see, you want the effects on the scene not the alphered bitmap on top. hmmmmm doesn't seem to work!!!
I think I'd work around it and render the scene with effects on it's own then use the result as a bitmap sequence in VP for a second go with the alpha image.
EricChadwick
08-28-2003, 05:40 PM
OK, thanks for double-checking. Too bad, I was hoping for a quicker method... seems like VP ought to be able to do this... a seemingly common compositing task.

I'll ask on the Discreet board, see if anyone comes up with something.
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