Alpha Channels

streckfus wrote on 2/15/2001, 7:38 AM
I've been having problems with setting transparency on text
effects. I'm trying to create a text effect where the
LETTERS of the text are transparent INSTEAD of the
background color, thus allowing an underlying video clip to
be seen through the letters of the text. I want a black
background, so when I go to "Properties/Media" I
choose "Premultiplied" with the color white (same as text
color) for the alpha channel. However, no matter what
color I choose as the alpha channel, VF by default seems to
set black as the alpha channel. So instead of getting a
black background with transparent letters and a video file
creating the shapes of the letters, I get a full frame
video with white text. What to do?


SonyEPM wrote on 2/15/2001, 9:13 AM
Create a new text event on track one, with your video
underneath in track 2.

Set text forground color to transparent (vertical slider
next to color picker, drag to bottom) and text background
color to opaque (vertical slider next to color picker, drag
to top). No need to adjust the alpha interp in properties.