Preserving transparancy

mel58i wrote on 7/12/2006, 4:21 AM

If I import a avi title with a solid background from another application , is there a way of rendering it to give a transparent background without having to chroma key it in vegas?

Mel.

Comments

farss wrote on 7/12/2006, 5:13 AM

The other application would have to support transparency and be able to render to a format that supports an alpha channel, e.g. uncompressed DV.
Also be aware that Vegas may not read the transparency correctly. Correct this by RClicking the media and under video force the transparency.

Bob.

mel58i wrote on 7/12/2006, 5:35 AM

Thanks Bob for your reply.
To tell the full story, I'm using Bluff titler but I've got a problem with it.
It's fine rendering to uncompressed with transparancy, but cannot find the codecs for compressed (and crashes the pc).
BT says it's a windows problem, but I cannot solve it!
That's why I'm forced to using uncompressed, but the file size is enormous. Hence the need to compress to DV (with transparancy) to save for later use.
Any ideas?

Mel.

Former user wrote on 7/12/2006, 5:51 AM

Compressed formats do not support an Alpha channel, which is what is needed to support transparency. Your other option is to use Chroma key by creating a solid color background in Bluff titler.

Dave T2

TomE wrote on 7/12/2006, 6:03 AM

You can also export Targa frames with transparency. Then when you import to Vegas use the import still image sequence and it will bring them all in. You then right click the media to make sure to check the right setting for the alpha channel. (don't remember off hand which one to use (premuliplied or whatever)

-TomE

Jim H wrote on 7/12/2006, 7:37 AM

In Bluff select generate movie and use the uncompressed format with transparancy. In Vegas, right click for properties and go to the next tab (not looking at vegas so I'm guessing) and turn on Alpha channel and select "dirty" or something like that. I'm using bluff and this works fine.

Jay-Hancock wrote on 7/12/2006, 9:15 AM

png files can also have transparency, and they are smaller than Targa files (but still lossless).

Quicktime's mov files can also have transparency. I don't know how they do it (does it use png in some way?). I don't have BT so I don't know if QT is a rendering option. But it's possibly interesting to know.