how to understand the spatial loss

[chen wei]

I can not understand the Lsp+ loss. The loss is computed between the pseudo ground-truth and the generated density map Dc. The BCE loss force the density map to peak at the pseudo ground-truth peak points. How to understand the effect of |S| and |B|sum in denominator.

[Guolei Sun]

Hi,

Thanks for your interest. |S| and |B|sum in denominator are just for normalizing the loss. Basically, it simply means that the loss is averaged over the number of peaks and number of classes in S.
In pytorch, the loss has some arguments to control whether to do average or not. Please refer to https://pytorch.org/docs/stable/nn.html#torch.nn.BCEWithLogitsLoss