Trackers on video of not the same FPS as Project (29.97 vs 30) is about a frame off (trackers incorrectly interpolate?)

[belisoful]

Apple Feedback Assistant ID: MISSING

DESCRIBE THE BUG:
There are severe timing problems with trackers placed on videos that are 29.97 fps but are in projects of 30 fps.
I can't tell if it's Plus or minus one frame off. It may be a smoothing issue as well? It's almost as if it were tracking on the interpolation of the previous and next frame. The 0.03 fps seems to be desynchronizing the tracker timing in some really bogus ways.

It may be a timing and synchronization issue between the tracker data (29.97 based) and the main timeline in 30 fps.

This bug looks like it may also be adding spatial drift. The movement of objects attached to and moving with the tracker look like they move about 1.5x the distance of the tracker in one dimension. This is difficult to tell and requires more testing to confirm. It looks like there is bias being introduced to the tracking object that shouldn't be there as the tracker moves larger distances.

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TO REPRODUCE:
Drop a 29.97 fps video that shakes a little per frame. Shaking per frame makes it easy to identify timing. (it must be clear and not blurry)
Add a tracker to the video to track a quickly oscilating object.

If it's not too shaky or blurry, the tracker should track the element properly, however it doesn't. The tracker seems to be about ~0.2-1.2 frames ahead or behind. it looks like it's tracking something that's almost there but not there.

A larger movement in the tracker may push a tracking object further than a 1:1 relationship than should have.

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EXPECTED BEHAVIOUR:
The tracker should be tracking on the actual visual displayed rather than an interpolation of frames, or interpolating the tracker data.

I was able to tame the tracker jumping around in Einstein's space-time by putting the 29.97 video into a project Compound clip [running at 30 fps] and then tracking on the clip. Then everything worked perfectly fine.

The expected behavior of tracking on a 29.97 video in a 30fps project is the same as if the 29.97 video were first put in a clip and the same tracker applied. Radically different behavior to the point of making trackers pointless in such a condition.
thankfully, the work around is reasonable until this is fixed.

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SPECS:

• 2021 16-inch MacBook Pro (M1 Max, 32GB RAM, 2TB SSD)
• macOS Sonoma 14.5
• Final Cut Pro 10.8

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ADDITIONAL COMMENTS:

It looks like maybe a timing and synchronization issue between the tracker data on the 29.97 video and the main 30 fps timeline.