shrink matte or matte choking
- Thread starter Gord.T
- Start date
Are you doing a chromakey?
Apply a gaussian blur to the clip after you apply the chromakey. Then, in the blur effect control, uncheck R, G, and B. Leave A checked. Play with the blur until you shrink it as much as you want.
There's a more complicated way if that doesn't work.
Apply a gaussian blur to the clip after you apply the chromakey. Then, in the blur effect control, uncheck R, G, and B. Leave A checked. Play with the blur until you shrink it as much as you want.
There's a more complicated way if that doesn't work.
Gord.T
Still "Senior Member"
Thanks David. Actually I'm compositing a 3D render over video and would like to soften up the edges a bit of the 3D object render pass.
I tried the above method but it doesn't give the results I was looking for in this case.
I've played around a bit and have some success at this point(cleanly blurred edges) by parenting a seperate alpha video to the color video.
- Alpha video has a blending mode of Multiply Mask
- FX added to the alpha are Median, (used to shrink the mask) + Mask Generator + Gaussian Blur (with alpha unchecked) in that order.
Very sensitive though.
Here's 2 simple pics I used for testing. An alpha and a color if anyone wants to do a quick play with them. (Although they were originally Tiffs)
It seems to work.
I'll keep looking though and am open to other ideas.
I tried the above method but it doesn't give the results I was looking for in this case.
I've played around a bit and have some success at this point(cleanly blurred edges) by parenting a seperate alpha video to the color video.
- Alpha video has a blending mode of Multiply Mask
- FX added to the alpha are Median, (used to shrink the mask) + Mask Generator + Gaussian Blur (with alpha unchecked) in that order.
Very sensitive though.
Here's 2 simple pics I used for testing. An alpha and a color if anyone wants to do a quick play with them. (Although they were originally Tiffs)
It seems to work.
I'll keep looking though and am open to other ideas.
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Thanks David. Actually I'm compositing a 3D render over video and would like to soften up the edges a bit of the 3D object render pass.
I tried the above method but it doesn't give the results I was looking for in this case.
I've played around a bit and have some success at this point(cleanly blurred edges) by parenting a seperate alpha video to the color video.
- Alpha video has a blending mode of Multiply Mask
- FX added to the alpha are Median, (used to shrink the mask) + Mask Generator + Gaussian Blur (with alpha unchecked) in that order.
Very sensitive though.
Here's 2 simple pics I used for testing. An alpha and a color if anyone wants to do a quick play with them. (Although they were originally Tiffs)
It seems to work.
I'll keep looking though and am open to other ideas.
That is more or less the same thing, except you're using a track mask rather than a chromakey.
Gord.T
Still "Senior Member"
David, I tried your method again and maybe I'm doing it wrong but here's a couple test
comparisons. I think in your method, while maybe fine for green screening, I don't see where it can shrink the matte. It'll blur in both directions will it not?
If there was an option to do 1/ inner blur (ideal in this case, 2/ outter blur or 3/ both directions like the manual masking method, that would solve a lot of the headaches.
As it is, and again, I might be over zealous in my settings but here's a couple quick over kill comparisons.
The chroma keying (keying black in this case) plus gaussian blur method. I don't like the bleeding from the blue background. Onto a solid blue back color. And the edges aren't soft and tight. I can't get it to perform the way I want. (The text colors are different for this test so ignore that but you can see the blue bleeding and lack of edge shrinking.) [Maybe I'm missing something in the process.]
And here's the Median + mask + gaussian blur version.
At least in this case it appears to me that's it's cleaner, although shown with overkill settings for explanation purposes. I also find that The Median filter can shrink the mask up to about 25% which is overkill but lots of play there.
Maybe I wasn't doing it right. But this is kind of the control I was after. Most other programs like AE have shrink matte functions built in. I don't know why vegas doesn't.
comparisons. I think in your method, while maybe fine for green screening, I don't see where it can shrink the matte. It'll blur in both directions will it not?
If there was an option to do 1/ inner blur (ideal in this case, 2/ outter blur or 3/ both directions like the manual masking method, that would solve a lot of the headaches.
As it is, and again, I might be over zealous in my settings but here's a couple quick over kill comparisons.
The chroma keying (keying black in this case) plus gaussian blur method. I don't like the bleeding from the blue background. Onto a solid blue back color. And the edges aren't soft and tight. I can't get it to perform the way I want. (The text colors are different for this test so ignore that but you can see the blue bleeding and lack of edge shrinking.) [Maybe I'm missing something in the process.]
And here's the Median + mask + gaussian blur version.
At least in this case it appears to me that's it's cleaner, although shown with overkill settings for explanation purposes. I also find that The Median filter can shrink the mask up to about 25% which is overkill but lots of play there.
Maybe I wasn't doing it right. But this is kind of the control I was after. Most other programs like AE have shrink matte functions built in. I don't know why vegas doesn't.
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It tends to work for greenscreen; figured it couldn't hurt to try without knowing exactly what you were doing. I like the results in your second pic.