Fix MIND-SSC (#77)

* Add squared lncc and mind-ssc losses

* fix cpu error and add indexing parameter for meshgrid in mind-ssc

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Co-authored-by: Basar Demir <[email protected]>

src/icon_registration/losses.py

@@ -771,15 +771,15 @@ def compute_mindssc(self, img):
         dist = self.pdist_squared(six_neighbourhood.t().unsqueeze(0)).squeeze(0)
 
         # define comparison mask
-        x, y = torch.meshgrid(torch.arange(6), torch.arange(6))
+        x, y = torch.meshgrid(torch.arange(6), torch.arange(6), indexing='ij')
         mask = ((x > y).view(-1) & (dist == 2).view(-1))
 
         # build kernel
         idx_shift1 = six_neighbourhood.unsqueeze(1).repeat(1, 6, 1).view(-1, 3)[mask, :]
         idx_shift2 = six_neighbourhood.unsqueeze(0).repeat(6, 1, 1).view(-1, 3)[mask, :]
-        mshift1 = torch.zeros(12, 1, 3, 3, 3).cuda()
+        mshift1 = torch.zeros(12, 1, 3, 3, 3).to(img.device)
         mshift1.view(-1)[torch.arange(12) * 27 + idx_shift1[:, 0] * 9 + idx_shift1[:, 1] * 3 + idx_shift1[:, 2]] = 1
-        mshift2 = torch.zeros(12, 1, 3, 3, 3).cuda()
+        mshift2 = torch.zeros(12, 1, 3, 3, 3).to(img.device)
         mshift2.view(-1)[torch.arange(12) * 27 + idx_shift2[:, 0] * 9 + idx_shift2[:, 1] * 3 + idx_shift2[:, 2]] = 1
         rpad1 = torch.nn.ReplicationPad3d(self.dilation)
         rpad2 = torch.nn.ReplicationPad3d(self.radius)