Score values between two identical images

[Ellyuca]

Hi, thanks for this interesting work.
I am trying to use the test.py code to compute the IQT between two images.
I've been playing around with the code to understand it better. So I was doing a few runs using different images (from the PIPAL validation set).
I also tried to compute the score between two identical images (A0005.bmp) and the prediction is 0.7645590901374817.
I am wondering if this is correct, since for example with other FR metrics like SSIM the score between two identical images is 1.
Is there some specific parameters that I need to change in the config? Or is this normal behaviour for this metric?
Also, what is the score range min and max value? is it between 0 and 1?

Thank you.
Have a great day.