From d00d368cdb32cb484a6e42cfef2d3da544b8044f Mon Sep 17 00:00:00 2001
From: Isaac Paul <izackp@gmail.com>
Date: Fri, 21 Aug 2015 10:59:07 -0400
Subject: [PATCH] Fix unsupported colorspace issue.

Without this fix, this url: https://abs.twimg.com/sticky/default_profile_images/default_profile_3_normal.png isn't correctly decoded and the method returns a nil image.. perhaps there should be a failsafe that checks the return value and returns the input image instead if the return value is nil.
---
 SDWebImage/SDWebImageDecoder.m | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/SDWebImage/SDWebImageDecoder.m b/SDWebImage/SDWebImageDecoder.m
index 9527603..3997089 100644
--- a/SDWebImage/SDWebImageDecoder.m
+++ b/SDWebImage/SDWebImageDecoder.m
@@ -29,17 +29,19 @@
     size_t width = CGImageGetWidth(imageRef);
     size_t height = CGImageGetHeight(imageRef);
 
-    // default RGB
-    CGColorSpaceRef RGBcolorSpace = CGColorSpaceCreateDeviceRGB();
-
     // current
     CGColorSpaceModel imageColorSpaceModel = CGColorSpaceGetModel(CGImageGetColorSpace(imageRef));
+    CGColorSpaceRef colorspaceRef = CGImageGetColorSpace(imageRef);
+    
+    bool unsupportedColorSpace = (imageColorSpaceModel == 0 || imageColorSpaceModel == -1 || imageColorSpaceModel == kCGColorSpaceModelIndexed);
+    if (unsupportedColorSpace)
+        colorspaceRef = CGColorSpaceCreateDeviceRGB();
 
     CGContextRef context = CGBitmapContextCreate(NULL, width,
                                                  height,
                                                  CGImageGetBitsPerComponent(imageRef),
                                                  0,
-                                                 (imageColorSpaceModel == 0 || imageColorSpaceModel == -1) ? RGBcolorSpace : CGImageGetColorSpace(imageRef),
+                                                 colorspaceRef,
                                                  kCGBitmapByteOrderDefault | kCGImageAlphaPremultipliedFirst);
 
     // Draw the image into the context and retrieve the new image, which will now have an alpha layer
@@ -47,7 +49,9 @@
     CGImageRef imageRefWithAlpha = CGBitmapContextCreateImage(context);
     UIImage *imageWithAlpha = [UIImage imageWithCGImage:imageRefWithAlpha];
 
-    CGColorSpaceRelease(RGBcolorSpace);
+    if (unsupportedColorSpace)
+        CGColorSpaceRelease(colorspaceRef);
+    
     CGContextRelease(context);
     CGImageRelease(imageRefWithAlpha);