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Author: fepegar

src/torchio/transforms/preprocessing/spatial/resample.py

@@ -410,6 +410,7 @@ def _get_sigmas(downsampling_factor: np.ndarray, spacing: np.ndarray) -> np.ndar
             spacing: Array with the spacing of the input image in mm.
         """
         k = downsampling_factor
-        variance = (k**2 - 1**2) * (2 * np.sqrt(2 * np.log(2))) ** (-2)
+        # Equation from top of page 678 of proceedings (4/9 in the PDF)
+        variance = (k**2 - 1) * (2 * np.sqrt(2 * np.log(2))) ** (-2)
         sigma = spacing * np.sqrt(variance)
         return sigma