Skip to content
Open
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions README.md
Original file line number Diff line number Diff line change
Expand Up @@ -51,11 +51,11 @@ img1 = Variable( img1, requires_grad=False)
img2 = Variable( img2, requires_grad = True)


# Functional: pytorch_ssim.ssim(img1, img2, window_size = 11, size_average = True)
# Functional: pytorch_ssim.ssim(img1, img2, window_size = 11, size_average = True,reduction='mean')
ssim_value = pytorch_ssim.ssim(img1, img2).data[0]
print("Initial ssim:", ssim_value)

# Module: pytorch_ssim.SSIM(window_size = 11, size_average = True)
# Module: pytorch_ssim.SSIM(window_size = 11, size_average = True,reduction='mean')
ssim_loss = pytorch_ssim.SSIM()

optimizer = optim.Adam([img2], lr=0.01)
Expand Down
27 changes: 15 additions & 12 deletions pytorch_ssim/__init__.py
Original file line number Diff line number Diff line change
Expand Up @@ -14,7 +14,7 @@ def create_window(window_size, channel):
window = Variable(_2D_window.expand(channel, 1, window_size, window_size).contiguous())
return window

def _ssim(img1, img2, window, window_size, channel, size_average = True):
def _ssim(img1, img2, window, window_size, channel, size_average = True, reduction = 'mean'):
mu1 = F.conv2d(img1, window, padding = window_size//2, groups = channel)
mu2 = F.conv2d(img2, window, padding = window_size//2, groups = channel)

Expand All @@ -30,19 +30,22 @@ def _ssim(img1, img2, window, window_size, channel, size_average = True):
C2 = 0.03**2

ssim_map = ((2*mu1_mu2 + C1)*(2*sigma12 + C2))/((mu1_sq + mu2_sq + C1)*(sigma1_sq + sigma2_sq + C2))

if size_average:
return ssim_map.mean()
else:
return ssim_map.mean(1).mean(1).mean(1)

if reduction == 'mean':
if size_average:
return ssim_map.mean()
else:
return ssim_map.mean(1).mean(1).mean(1)
elif reduction == 'none':
return ssim_map
# reduction can be 'mean' or 'none'
class SSIM(torch.nn.Module):
def __init__(self, window_size = 11, size_average = True):
def __init__(self, window_size = 11, size_average = True, reduction= 'mean'):
super(SSIM, self).__init__()
self.window_size = window_size
self.size_average = size_average
self.channel = 1
self.window = create_window(window_size, self.channel)
self.reduction = reduction

def forward(self, img1, img2):
(_, channel, _, _) = img1.size()
Expand All @@ -60,14 +63,14 @@ def forward(self, img1, img2):
self.channel = channel


return _ssim(img1, img2, window, self.window_size, channel, self.size_average)

def ssim(img1, img2, window_size = 11, size_average = True):
return _ssim(img1, img2, window, self.window_size, channel, self.size_average , self.reduction)
# reduction can be 'mean' or 'none'
def ssim(img1, img2, window_size = 11, size_average = True, reduction='mean'):
(_, channel, _, _) = img1.size()
window = create_window(window_size, channel)

if img1.is_cuda:
window = window.cuda(img1.get_device())
window = window.type_as(img1)

return _ssim(img1, img2, window, window_size, channel, size_average)
return _ssim(img1, img2, window, window_size, channel, size_average, reduction)