Is it correct how to compute the variance?

[taikiinoue45]

I have a question about how to compute the variance.

pytorch-ssim/pytorch_ssim/__init__.py

Line 25 in d6adfb5

sigma1_sq = F.conv2d(img1*img1, window, padding = window_size//2, groups = channel) - mu1_sq

[taikiinoue45]

Here is the definition of the variance.

[taikiinoue45]

To me, your implementation looks like the following.

[taikiinoue45]

I think this is a correct implementation. What do you think about this?

sigma1_sq = F.conv2d(img1 - mu1, window, padding = window_size//2, groups = channel).pow(2)

[taikiinoue45]

Sorry, it's my bad. Your implementation is correct.