Is multiple optimal frames reported allowed?

I check the training data and found that there are multiple optimal frames in the GT label. When we submit the fetal-abdomen-frame-number.json, can there be multiple numbers in the file? Or just one allowed? Because when I check the baseline code, it only outputs the frame with largest area of optimal seg.

Only one frame is allowed as output. The baseline algorithm implements a dummy selection for it. You can work on a better alternative.

Even if your algorithm detects multiple frames, you should select and output one. If it also corresponds to an optimal (or suboptimal) one in the ground-truth, you will get points for this via the Weighted Frame Selection Score

Weighted Frame Selection Score (WFSS): WFSS evaluates the algorithm's frame selection accuracy, assigning higher scores to accurately identified and chosen clinically relevant frames. A score of 1 denotes correct identification of optimal planes, 0.6 for suboptimal plane selection when an optimal is available, and 0 for the selection of irrelevant frames when optimal/suboptimal ones are present.