diff --git a/concatimages.py b/concatimages.py
index 4d400bf..67c0603 100644
--- a/concatimages.py
+++ b/concatimages.py
@@ -7,6 +7,18 @@
 i1=cv2.resize(picture,(600,450))
 i2=cv2.resize(picture,(600,450))
 print(i2.shape,i1.shape)
+
+    if isinstance(colors, str):
+        cmap = cm.get_cmap(colors, N)
+        cmap = cmap(np.arange(N))
+        colors = cmap[::-1,:].tolist()
+    if isinstance(colors, list): 
+        if len(colors) == N:
+            colors = colors[::-1]
+        else: 
+            raise Exception("\n\nnumber of colors {} not equal \
+            to number of categories{}\n".format(len(colors), N))
+
 nhorizontal=np.hstack((i1,i2))
 cv2.imshow("combined",nhorizontal)
 cv2.waitKey(0)