Help using Viewport function

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Mugwood
Posts: 9
Joined: Wed Jun 05, 2019 6:00 am

Help using Viewport function

Post by Mugwood »

I have been using the Viewport function to create a transparent section on one half of the video to do a back-projection type of thing -- but have struggled a bit to understand the best ways to use Viewports. There are only a couple of lines in the help file, so would appreciate some guidance :)

Firstly, I thought Viewports would allow effects to occur only inside the Viewport - however when I tried to select one half of the image with a Viewport and apply the transparency effect, it didn't seem to work.

It's also a little confusing with the meaning/use of Top Layer, Back Layer and Original in the Viewport settings - how should these be used?

In the end I got it working by duplicating the main video across 2 tracks, with identical Viewports for the left side of the image where there is no transparency (i.e. Viewports on the left side for "no transparency" no Viewport on the right side where transparency would be used). The final arrangement is something like this:

TRACK 1 : Main video, viewport on left 50%, set to Back Layer
TRACK 2 : Back projection video
TRACK 3 : Main video, viewport on left 50%, set to Top Layer

I can then fade in the back projection to the colour-keyed transparent section as needed... though doing fades on the 2 main videos have to be identical.

Can you recommend a better way to do something like this?

Thanks!
Mugwood
Posts: 9
Joined: Wed Jun 05, 2019 6:00 am

Re: Help using Viewport function

Post by Mugwood »

Or perhaps is it a feature/conflict specific to the transparency effect?

I can apply some effects within a Viewport (blur, colour shift, colour levels) but transparent colour doesn't seem to work just within the viewport.

Or perhaps I am just permanently confused ;)
GoldWave Inc.
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Re: Help using Viewport function

Post by GoldWave Inc. »

It should be possible to have transparent areas in the Viewport. I'll check into it.
Mugwood
Posts: 9
Joined: Wed Jun 05, 2019 6:00 am

Re: Help using Viewport function

Post by Mugwood »

Many thanks - I'm working on another project with split screens PLUS transparency on color-keyed sections, so this would be very helpful :)

Let me know if I can help test anything?
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