fix bugs in save_image

torchvision/utils.py

@@ -16,9 +16,10 @@ def make_grid(tensor, nrow=8, padding=2):
         for i in range(numImages):
             tensor[i].copy_(tensorlist[i])
     if tensor.dim() == 2: # single image H x W
-        tensor = torch.view(1, tensor.size(0), tensor.size(1))
-        tensor = torch.cat((tensor, tensor, tensor), 0)
+        tensor = tensor.view(1, tensor.size(0), tensor.size(1))
     if tensor.dim() == 3: # single image
+        if tensor.size(0) == 1:
+            tensor = torch.cat((tensor, tensor, tensor), 0)
         return tensor
     if tensor.dim() == 4 and tensor.size(1) == 1: # single-channel images
         tensor = torch.cat((tensor, tensor, tensor), 1)