Easiest Track in the world fails

White circle. Black background. Nothing else. Mocha can’t track it no matter what settings I use. Why?

I’m trying to track a ball that a guy tosses barely over his head (off screen) and then catches. Despite great color separation, Mocha didn’t do well with that due to motion blur and fingers on the ball (I assume) so I manually keyframed a beautiful spline, frame by frame. But it’s not a roto I want, and Mocha doesn’t have the ability to utilize the XY (etc) data from that spline, so I rendered the matte and brought this white “ball” on a black screen in to track. But Mocha fails at it spectacularly, often confusingly considering the wonders I’ve seen Mocha pull off elsewhere. As I said, I’ve tried every Track setting imaginable. Is there something special about simple, high-contrast geometric shapes that Mocha can’t stomach?

Here’s a picture of what happens when I turn on Perspective tracking (anything less than that simply fails). The previous frame was perfect and the circle only moved 50 to 100 pixels, tops.

Okay, I lied about trying EVERY setting. I tracked rotation (!?!) and that seems to have done something. (and BTW, there IS no rotation, Mocha). But just leaving it on is no good. Every frame is special, even when the circle doesn’t even leave the search spline.

Quite simply, mocha is a planar tracker which tracks texture. If there isn’t any texture, it’s going to have a hard time.

You may be able to track this by just using “Translation” in the motion properties.

But it also depends on how fast the object is moving. How much pixel distance is covered per frame?

So you’re saying… user error? :wink: Interesting experiment, though. Thanks for enlightening me.

Not really, just limitations of the software. :slight_smile:

Bright, high contrast flat colour is hard to track!

Pixel distance is also a factor however. If the ball is moving VERY fast, you may need to up the search area parameters.