2nd LPT Challenge Case 2 TR Results

Second LPT Challenge Case 2: Time-Resolved results

This page presents published results for the Time-Resolved case 2nd LPT Challenge Case 2. The link for result submission, as well as details about the test case and  rules for result 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 this specific test case, where a subset of the particles are viewed by only 2 or 3 cameras at low I/U ratio, quantities for performance evaluation are estimated on the set of particles which are viewed by all 4 cameras. 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) errors, whether on particle position, velocity or acceleration, are defined by considering only the TP within the result. Corresponding units are as follows:

• Position errors (raw and fitted) are given in voxel, with a voxel size here equal to 30.5 µm
• Velocity errors are dimensionless, with corresponding reference velocity V_inf = 10 m/s
• Acceleration errors are dimensionless, with corresponding reference acceleration A_inf = V_inf²/D = 10,000 m/s², where D = 0.01 m is the cylinder diameter (see there for more information on the physical setup).

Below, we provide tables showing these quantities for all test points. Then, we show figures comparing these quantities among participants, as well as groups of error slices for velocity and acceleration at a given test point.