Figure 3

These are illustrations of five standard problems LACE_ac toolbox can automatically detect and solve. Problem 1 and 2 are superfluous detections of either the same animal (Problem 1) or other contrast areas in the video frame like shadows (Problem 2). Both are solved by deleting the detection with the lower quality rating. Problem 4 results from one of the detection ellipses not passing all criteria (size, eccentricity, last position) and is solved by taking the detection with the highest quality from the sub-threshold detection list. Problem 5 to 7 are all due to a miss-detection in which two or more animals are lumped together, because of their proximity. These are mainly solved by deleting detections that are too large and choosing from the sub-threshold detection list (Problems 5 and 6) or by splitting up the chain in animal long regions (Problem 7).