fixed data casting

Author: chrisgorgo

nipype/algorithms/confounds.py

@@ -464,7 +464,7 @@ def _run_interface(self, runtime):
             mask_data = np.zeros_like(in_mask_data)
             mask_data[in_mask_data != 0] = mask
         else:
-            mask_data = mask
+            mask_data = mask.astype(int)
 
         # save mask
         mask_file = os.path.abspath('mask.nii')