Why not calculating TVloss during forward pass?

[kaca0083]

Hi. Comparing TVLoss:updateOutput(input) with TextureLoss:updateOutput(input), I found that the code didn't calculate TVLoss during forward pass but only calculate the gradient of TVLoss during backward pass. Any idea why?

[austingg]

in fact the TV Loss is used to keeping the result image smooth. It only affect the input image, not affect the conv layers.