2nd LPT Challenge Case 3 TP Results

Second LPT Challenge Case 3: Two-Pulse results

This page presents published results for the TP (Two-Pulse) case of the 2nd LPT Challenge Case 3. The link for result submission, as well as details about the test case and rules for result formatting are given there.

Tables can be ordered according to each of the quantities reported. Clicking on an algorithm name in a table will open a page gathering its result, together with information on the submitter.

Definition of performance metrics

Evaluation pertains to both particle localization, at the two pulse times t0 and t1, and estimation of the displacement vectors. For either particles or vectors, we count :

• a True Positive (TP) if a ground truth (GT) particle is found in the neighborhood of a detection (maximum componentwise distance less than 1 voxel). For vectors, both detections should be TPs and associated to the same GT particle.
• a False Negative (FN, a.k.a. missed particle) if there is no detection in the neighborhood of a GT particle. A FN vector is a GT vector that is not associated to a TP vector.
• a False Positive (FP, a.k.a. ghost particle/vector) particle/vector when it is not a TP particle/vector.

Precision and Recall are derived quantities reflecting the detection performance, defined as:

Root-mean-square (rms) error on particle position or displacement are defined by only considering the TP within the result. 

In the tables, they are given in voxel, with a voxel size here equal to 528 µm; figures also show these errors in mm. Conversion from displacement to velocities can be done straightforwardly by considering the acquisition frequency, set to 30 Hz; for reference, the free-stream velocity is here equal to 0.6633 m/s.

Below the tables, we provide plots comparing some of these quantities among participants, as well as displacement error slices for a selected test point.