Alignment: fixed typo

Signed-off-by: Nicola VIGANÒ <nicola.vigano@esrf.fr>

nabu/preproc/alignment.py

@@ -372,7 +372,7 @@ class AlignmentBase(object):
     def _compute_correlation_fft(img_1, img_2, padding_mode):
         do_circular_conv = padding_mode is None or padding_mode == "wrap"
         if not do_circular_conv:
-            padding = np.ceil(np.array(img_2.img_shape) / 2).astype(np.int)
+            padding = np.ceil(np.array(img_2.shape) / 2).astype(np.int)
             img_1 = np.pad(img_1, ((padding[0],), (padding[1],)), mode=padding_mode)
             img_2 = np.pad(img_2, ((padding[0],), (padding[1],)), mode=padding_mode)