From db95e63a632bc0bd62f1842bda8ef30e0e6df6ff Mon Sep 17 00:00:00 2001
From: BaBaBags <ryan@ryanbagwell.com>
Date: Tue, 23 Aug 2011 10:20:37 -0400
Subject: [PATCH] Added support for preserving transparency when converting
 from color to greyscale

---
 imagekit/utils.py | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/imagekit/utils.py b/imagekit/utils.py
index af8d40f..3582023 100644
--- a/imagekit/utils.py
+++ b/imagekit/utils.py
@@ -4,6 +4,14 @@ import tempfile
 
 def img_to_fobj(img, format, **kwargs):
     tmp = tempfile.TemporaryFile()
-    img.convert('RGB').save(tmp, format, **kwargs)
+    
+    #preserve transparency if the image is in Pallette (P) mode
+    if img.mode == 'P':
+        #assert False, img.info
+        kwargs['transparency'] = 255
+    else:
+        img.convert('RGB')
+    
+    img.save(tmp, format, **kwargs)
     tmp.seek(0)
     return tmp