Fix typo

bob/ip/stereo/calibration.py

@@ -38,7 +38,6 @@ def detect_chessboard_corners(image, prep_im, pattern_size, verbosity):
             im = cv2.cvtColor(image, cv2.COLOR_GRAY2BGR)
         else:
             im = cv2.cvtColor(prep_im, cv2.COLOR_GRAY2BGR)
-        prev = np.copy(im)
         draw_image = cv2.drawChessboardCorners(im, pattern_size, im_points, True)
         plt.imshow(draw_image, vmin=0, vmax=255)
         plt.show()
@@ -450,7 +449,7 @@ def main():
         image_size = image_data[camera]
         for camera_2 in stream[idx+1:]:# or with itertools.tee()
             if image_data[camera_2] != image_size:
-                raise ValueError("Image size between {} and {} does not match.".format(camera, camera2))
+                raise ValueError("Image size between {} and {} does not match.".format(camera, camera_2))
             if not "df_extrinsics_{}".format(camera_2) in calibration[camera].keys():
                 continue
             df = calibration[camera]["df_extrinsics_{}".format(camera_2)]