diff --git a/imagelib/color_transfer.py b/imagelib/color_transfer.py
index 67a580d..2b085d5 100644
--- a/imagelib/color_transfer.py
+++ b/imagelib/color_transfer.py
@@ -138,11 +138,11 @@ def linear_color_transfer(target_img, source_img, mode='pca', eps=1e-5):
 
 def lab_image_stats(image, mask=None):
     # compute the mean and standard deviation of each channel
+    l, a, b = cv2.split(image)
+
     if mask is not None:
         mask = np.squeeze(mask)
-        image = image[mask == 1]
-
-    (l, a, b) = cv2.split(image)
+        l, a, b = l[mask == 1], a[mask == 1], b[mask == 1]
 
     l_mean, l_std = np.mean(l), np.std(l)
     a_mean, a_std = np.mean(l), np.std(l)