train transform

[sunmengnan]

in the first line of train transform, why is transforms.Resize(250.0 / iheight) for computational efficiency?
transform = transforms.Compose([
transforms.Resize(250.0 / iheight), # this is for computational efficiency, since rotation can be slow
transforms.Rotate(angle),
transforms.Resize(s),
transforms.CenterCrop((228, 304)),
transforms.HorizontalFlip(do_flip),
transforms.Resize(self.output_size),
])