HELP! Having Problems Rotoscoping some Tracked Footage

Morning all-
I’m having some issues with understanding an error that’s occurring while rotoscoping. I’m thinking (hoping) that it’s something someone can point out relatively easily.

I have tracked some footage of a rainy day in a parking garage. Actually very happy with the tracked footage, no problems there, with a low projection error.

However, when I shot the scene, I left a white pipe from my camera dolly on the ground. It’s a sore thumb, and I decided to try and rotoscope it out of there. The pipe is surrounded by an area of very clean space, and I want to take that space, rotoscope it, and pull it over on top of the pipe.

So, using the rotoscope tool, I rotoscoped a shape that acts as a mask layer over the clean ground, and I will translate that shape over the white pipe when I figure out this problem.

THE PROBLEM: Even though it appears that I am tracking the correct area when I look through the 3d view, when I render the image/movie the rotoscoped layer actually looks like it is sampling an area of the video that is far to the right of pipe. Instead of pulling in the dry, tan ground next to the right side of the pipe, it is pulling in the wet, rainy ground much farther to the right.

I realize now that this is the reason my past rotoscoping efforts have failed.

Screenshots (for the quick fix):

Files (for the not-so-quick-fix) - (.blend and footage)

Any help would be appreciated! While the end result may not look the greatest, it’s the technique that I am lacking. I’l be able to use this in a couple of other projects that I am doing.


Make sure the Video is matching in Width and Height and remember to match frame rate.

DOH! Yep, feeling like a bonehead. Thank you. The movie size was still set to 50% in the Scene panel. Thanks. F

As long as I’m at it- what’s the best way to eliminate the hard edge of the rotoscoped layer? dilate/erade node the alpha input followed by Blur?

You want a feathered edge So Yeah the Dilate/Erode be careful with and don’t do to much. Of course I am not an expert by any means so others may know some better techniques.

Might be a good idea to try to match the shutter angle from the footage so that the motion blur on the matte matches with the plate.

So, in Blender the word rotoscope means “paint over?” :slight_smile:

what’s the best way to eliminate the hard edge of the rotoscoped layer?

The compositing nodes in 2.62 and beyond include the Double Edge Matte node which should work for this.