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Unexpected behavior X-axis Only autotracker post and replies

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Unexpected behavior X-axis Only autotracker
Sander Wildeman
2 Posts

Dear tracker community,

I'm trying to get the X-axis Only feature of the autotracker to work to track an edge. However, the detected points still seem to wander off the x-axis when the feature is enabled, even going outside the search area sometimes (see attached screenshot).

I'm using tracker version 6.2 on Mac OS 12.7.5. I checked that the Java version is the bundled one.

Any ideas what might be going wrong or how to resolve this?

Best regards,
Sander

Attached File: Screenshot20241005at12.41.31.png


Replies to Unexpected behavior X-axis Only autotracker

Re: Unexpected behavior X-axis Only autotracker -
Sander Wildeman
2 Posts

A small update. I dug a bit into the OSP/Tracker source code on GitHub to see if I could find a cause for the behavior.

My current hypothesis is that it could have to do with the sub-pixel refinement step in the template matcher (media/core/TemplateMatcher.java). This optimization step seems to assume that the correlation peak is two-dimensional, while this is not the case for an edge (the direction parallel to the edge won't have a well defined (sub-pixel) peak location).

If this suspicion is correct (and this is indeed unintended behavior) a fix might be to make getMatchLocation() aware of the line (x-axis) along which the search is performed and project the (dx,dy) correction on this line.



Re: Unexpected behavior X-axis Only autotracker -
Johnnie Justice
2 Posts

hiiii,
geometry dash meltdown
To fix this, you can try checking the axis settings again, narrowing the search area to limit discrepancies, or saving and restarting the project to ensure the correct settings are applied. If the problem persists, there is a high possibility that this is a bug with this version. You may need to report it or try another version to see if the feature works more stably.
Regard,



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