Video transparency?

[adrmmusic]

Is there a way to make video transparency? For example, can I import a logo intro animation video and just have the background transparent?
Or import a video of particles and blend the particles with another background layer?

Currently the only thing I had success with is using the transparency feature in magic. Is there other blending options that works better?

[JEL]

Look for nodes such as Mask, Luma key, Blend mode.

[artnik]

With the modules JEL mentioned it's fairly trivial, as long as you have prepared the logo animation with a good solid colour as the background.

Luma Key (If the background is pure black and there's no pure black in the logo itself), and Chroma Key (if your background is pure green or pure blue).

A third option is to render a second animation containing the transparency information and use the Mask module to apply it.

[blackdot]

and a fourth option would be to use a picture or video that does actually support and contain an alpha channel like png (for image) or 'quicktime animation' or 'hap alpha' codec for videos (there are others but I forgot them)

[artnik]

@blackdot True that.

Wouldn't it be nice if the JPEGFolder was instead a generic IMAGEFolder that would allow you to load a series of alpha-channeled PNGs, or other format?

[blackdot]

@blackdot True that.

Wouldn't it be nice if the JPEGFolder was instead a generic IMAGEFolder that would allow you to load a series of alpha-channeled PNGs, or other format?

actually I think Eric said something about the jpg's being able to be run really fast and png's not. some kind of hardware accelleration. so that's why he settled for jpg's only.

instead you can just run 2 sequences, one the color sequence, the other the mask sequence and put them together. at least that's how i do it. you can even safe by exporting your mask sequence into bw only and not rgb.

[artnik]

Nice! Thanks for the suggestion – I never considered two folders of JPEGs for this.

[Magic]

actually I think Eric said something about the jpg's being able to be run really fast and png's not. some kind of hardware accelleration. so that's why he settled for jpg's only.

Yeah, here's the post where we were talking about it : viewtopic.php?f=2&t=738

[artnik]

Thanks Eric!