There's Got To Be A Better Way...

Kira_Douji · Post by **Kira_Douji** » Tue Mar 21, 2006 9:12 am

... to remove a character from a background. So far I've figured out two methods. In the first, you put your clip in AE and plot a zillion+ points around it to create a mask, which you change each frame. Okay. I don't really like this method, as I generally suck at it. The second method involves exporting hundreds of frames to bitmap files and cleaning every single frame in Photoshop. Now, Photoshop I can use well, so my gripe isn't that I just generally suck at it so much as it takes so long that I eventually just give up.

So my question is this; is there a third way, and if so what is it called and where can I learn about it?

Thank you,
Kira

BasharOfTheAges · Post by **BasharOfTheAges** » Tue Mar 21, 2006 10:08 am

Well, those are the only 2 methods i've ever heard of. You can re-use masks somewhat though, right?

Coderjo · Post by **Coderjo** » Tue Mar 21, 2006 1:13 pm

Hollywood effects studios possibly have a faster way, but generally they don't like sharing their tools with competition. And I'm not counting chromakey (aka "bluescreen" or "greenscreen").

You could possibly set up a rotoscope outline on the first frame, and then have a program use that to try and follow the object, updating the line each frame. You'd have to write your own program to do this, though, or have someone you know write it. I don't know of any existing tools to do this, offhand. They would probably be pricey or proprietary internal tools for effects companies.

If you do find or write a tool for this, after you run it to generate your rotoscope masks, you will want to step through what it generated and make sure everything is right. Telling a computer to do what the human visual cortex can do is quite difficult.

Keeper of Hellfire · Post by **Keeper of Hellfire** » Tue Mar 21, 2006 1:29 pm

Two other possible methods come to mind, but the success depends on the footage. If the background hasn't much colors (like blue sky and green meadows) and they are distinct from the colors of the person, chromakeying may be your friend. And if you have a steady background and have at least one frame of the background without the person, differential keying can help you.

Kira_Douji · Post by **Kira_Douji** » Tue Mar 21, 2006 1:38 pm

I'm getting the impression that my original statement was incorrect --; Thank you for offering what you know, though.

- Kira