About magicpoint export on coco2014

[cxy99zyr]

Sorry to bother you again, I'm having another question, why do the coordinates of the feature points I output with MagicPoint on the coco image seem to be limited to a certain range instead of the whole image：

I saw your note about the adjustment of datasize in preprocessing, is it related to this?
Thanks for the answer, it will help me a lot！ @rpautrat