#Video Post – alpha ?
8 messages in this thread
Gary,
I am having a few problems using video post. What I want to do is
render a 3ds scene in video post and then do a pull focus on the
camera do obtain my effect. Not a problem so far (blur.ixp) , but I
also need to blur the alpha chanel of the image so that when I export
the images to our paint system I recieve a blured cut-out, at the
moment what happens is, I get a blurred image with a clean sharp
matte. I could probably do what I want by rendering the sequence with
alpha-split and then bluring the two sets of images but then I would
need to combine the 24 bit and the 8 bit images to create my cut-out.
Any answers or clues to help me out would be appreciated.
You've got the right idea. David Stinnett has already spoken
eloquently about the subject. (and I quote)
Thanks for the quick response, I actually remember reading that
message a while ago. I think that the effect that I am after is a bit
simpler than the one you explained. I only need to blur the 3d model
and the asscoiated matte. I would like to keyframe the effect and
therefore cannot use photoshop.
You can use blur.ixp instead of Photoshop. Just follow the same procedure
David outlined (using Alpha Split).
– G
>> I only need to blur the 3d model and the asscoiated matte.
Just run the blur filter over the scene, but render with alpha
and set "split alpha" to yes. Then bring in the alpha frames that
were created by the split, and run blur over those too, with the same
settings. This should work fine, the only difference being that
instead of 32 bit TGAs, you now have a set of 24 bit TGAs and a
separate set of 8 bit alpha channel TGAs, all blurred and usable as
masks.
David Thanks for your reply, unfortunatly we do need 32 bit files
only, I wonder if there is a util that will enable us to join the 24
bit and the 8 bit together ??
-Phil
>> I wonder if there is a util that will enable us to join the 24 bit and the 8
bit together ??
You can do this in 3ds. In video post, load an IFL listing the
24 bit TGAs in the queue. In the alpha slot for the entry put an IFL
listing the split 8 bit TGAs as an RGB Mask. then render (with no
background), and if you have "render alpha" set to YES (but Split to
No), and render to disk, the resulting files will be true 32 bit
files with the proper alpha.