yangfangs / pneannotaiontool Goto Github PK

In the below code (https://github.com/yangfangs/PneAnnotaionTool/blob/master/anntool.py) you are using a dFactor and want to clarify.

def setDicomWinWidthWinCenter(self,img_data, winwidth, wincenter):
img_temp = img_data
img_temp.flags.writeable = True
rows = img_data.shape[0]
cols = img_data.shape[1]
min = (2 * wincenter - winwidth) / 2.0 + 0.5
max = (2 * wincenter + winwidth) / 2.0 + 0.5
dFactor = 255.0 / (max - min)

what is the purpose of code: (dFactor = 255.0 / (max - min))
I would like to understand a little fundamentally.