Tracking ball shape in Hitfilm Pro

I've got a pretty basic understanding of vfx terms and stuff (been using other software on and off for a while) but still open to cave-man speak lol.

I've got a ball in my clip that i would like to track through the air. The specific clip in question is a recording of a match in a game called Rocket League. i thought this would be a nice challenge to learn some new skills as a hobbyist, however i have run into this issue. 

Using mocha, it tracks only to one point on the geometry of the ball, and as the ball rotates, the shape of my mask//outline moves with the rotation rather than simply the movement of the circle across the 2d plane (meaning the outline will like, "pinch" itself as the part of the ball that was facing the camera in the beginning rolls away.) (happens even if i only have it set to track translation, which tells me i don't understand how mocha actually tracks things.)

Using the "add tracker" button in the composite editor has the same effect, it tracks to a point on the ball instead of just the circle shape, rotating the outline with it. 

My question: is there a way to track to the circle shape in an automated way, or am i stuck masking by hand?



  • AxelWilkinsonAxelWilkinson Staff Administrator, Imerge Beta Tester, HitFilm Beta Tester Posts: 5,232 Staff
    edited December 2019

    Are you trying to track:

    A ) The position of the ball
    B ) The movement of the surface of the ball
    C ) The rotation of the ball?

    If you can give us a better sense of what you are trying to accomplish, we can offer tips for what sort of tracking would work best to achieve it.

  • OofDoesNotStreamOofDoesNotStream Website User Posts: 13

    i am essentially trying to overlay a circle over the visible space of ball at all times. so (A) the position of the center of the ball is what i am trying to track. thanks!

  • AxelWilkinsonAxelWilkinson Staff Administrator, Imerge Beta Tester, HitFilm Beta Tester Posts: 5,232 Staff

    In that case, it will be simplest to use the 2D tracker built into HitFilm. On the video layer, add a tracker, and set it up to track the ball, with the track point in the center of the ball. Then, once you assign that tracking data to a point layer, you have the position. Create whatever circle layer you want to overlay onto the ball, parent it to that point, and you are good to go.

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