While processing my first Game On! video I came across a bit of an issue. I had rendered a lower 3rd banner in After Effects and wanted to import it as a layer into Sony Vegas which I use to do the final processing of my videos. The problem was when I imported the video, it usually imported with a black background.
I had done a search for this in Google and surprisingly found very little in ways of importing transparent videos, all I could find was how to import transparent backgrounds (usually involving a PNG file). I did how ever find one saving grace, one of the youtube videos explained exactly how to do it. Trollshopping published a video entitled
Tutorial: How to render transparent clips in After Effects & the tricky ìmport in Sony Vegas
In the comments they state what needs to be done (I reformatted it to make the steps more clear):
In After Effects
- Have your Transparency Toogle Grid in transparent mode enabled
- Add composition to render queue
- Go to lossless-option
- Go with a format supporting alpha-channels (like AVI)
- Set RGB to RGB+ALPHA in the channel option!
- Press OK
Note: The size of the video is going to be quite large and take a while to render as it is rendering both RGB and Alpha at the same time. My export was only a few seconds long but took 5 minutes to render and was over 1GB in size.
In Sony Vegas
- Import your clip rendered in After Effects into Vegas like you import every other file
- Drop your clip on the timeline. it will not be transparent.
- Right Click on it
- go to Properties
- Select the Media tab
- Change the AlphaChannel option from Undefined to PreMultiplied.
Note: Because the file size is very large for your transparency, preview may be jittery and rendering will take a bit longer to process, however the output is amazing.
Hope this helps people find the answer quicker as this does not seem to be a very popular question on the net.