espite the fact that I cannot rollback to old versions of the algorithm — those that worked much better — I have run experiments on half of the entire Texas database. The performance was vastly inferior because of changes that I have made over the past couple of months.

Over the past few days I experimented with other smoothing schemes, as a colleague once suggested that I do. The improvements were very minor once performance was assessed with some ROC curves (few dozens of pairs). The general idea was, by removing areas or artifacts that distract from identity-related entropy, we can improve overall performance. The impediment has always been that, given too lenient and sensitive a measure, the items being compared are not identity-related but pose-related, noise-related, etc.

In my most recent experiments I have been looking into more kinds of masks, but none so far offers a magic solution with state-of-the-art performance.

Symmetric mask where eyes are removed and the nose tip too, in order to accentuate topology and delve into areas more “stable” than eye surface

Examples of correct matches where the mask is symmetric (the “classic” mode)

Examples of correct matches where the mask is cut at nose level

Examples of correct matches where the mask is intentionally asymmetric (to avoid flipping over)

I decided to tweak this further, testing GMDS for surfaces with holes.

Dealing with the existing algorithm, which performs more weakly than months ago (due to experimental changes that are hard to selectivity rollback), I have some new results. I have tested it with and without support (difference in dilation/distance for FMM cutoff), but in both cases the ROC curves were too disappointing to be worth plotting and showing. The approach does not seem suitable for good performance to be reached. With or without the most performance-promising algorithm, the general observation is that GMDS does not deal well with these holes (connected torus-like shapes).

Example of pairs of surfaces where eyes and nose tip got removed

An increasing level of geodesic dilation where eyes are cropped out but not the nose tip

ROC curves for the above

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