Hello,
My project has transparency in it, and I need to render both the RGB video file and a grayscale video that contains the matte with the transparency. This is for compatibility with other software that doesn't support transparency directly - Often times you will receive a video and a companion matte video like this:
How do I render the transparency/alpha matte video from Vegas Pro 17?
Thanks in advance!
There's probably a much easier way to do this, but you could max out brightness/contrast on the video until it is all white against a transparent background, then drop some black solid color media from the media generators behind it to give it a back background.
I don't know of any current video software that doesn't support an alpha channel. Does it really need to be a separate matte video, or does it need to have an alpha channel?
@fr0styThe problem with that approach is that I'll lose the gray values where there's semitransparency.
@Former user Yes, my specifications are to deliver two separate videos, one as a matte, and not a video with alpha. It's for use in some custom app that my employers have developed.
@pmjm
One way to do is to set your preview to display the alpha channel and then use a script to export an image sequence based on the rendered preview (just like using the "Save Snapshot" button of the preview).
Another way is to use the Mask Generator FX, if your source video already uses the alpha channel. Then in the Mask Generator FX use the default setting and only set the type to "Alpha".
Both results may differ a bit. I think one outputs a premultiplied matte and the other one an unpremultiplied matte, Still investigating.
I made a short video on Vegas Pro 14 showing the process. It will also work on Vegas Pro 17.
By default the Quick Time codec is disabled in Vegas Pro 17 and, if you need to render with a transparent background you will need to enable the Quick Time Codec in Options / Preferences / Deprecated Features.
@joelsonforte.br Thank you for that! The Mask Generator -> Alpha Mask effect is the key! I'll import my project into a new project and apply the effect to the whole thing. Also thank you to @marco. and everyone else who replied to this.