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Magnitude of differential motion vs. separation between pairs, for all 4 images:
Looks like fitting differential motion vs. sqrt(separation) might work. Did those fits, here are the results:
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| frame | b | a |
|---|---|---|
| 42 | 0.1150 | 0.0579 |
| 50 | 0.1139 | -0.0306 |
| 58 | 0.0654 | -0.0189 |
| 81 | 0.0309 | 0.0345 |
Those are the lines on the plot above.
MATLAB code DIMSUM.m is here: DIMSUM.m
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