From bb02b247a7f08d6cc2091d6fee2bbbd79a6cfe07 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=82=93=E6=B3=A2?= <dengbo03@maoyan.com>
Date: Sat, 4 Mar 2017 14:49:59 +0800
Subject: [PATCH] fix image alpha premultiplied

---
 FXBlurView/FXBlurView.m | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/FXBlurView/FXBlurView.m b/FXBlurView/FXBlurView.m
index 73c6f91..55d2b22 100755
--- a/FXBlurView/FXBlurView.m
+++ b/FXBlurView/FXBlurView.m
@@ -117,10 +117,26 @@ - (UIImage *)blurredImageWithRadius:(CGFloat)radius iterations:(NSUInteger)itera
     free(buffer2.data);
     free(tempBuffer);
 
+    CGImageAlphaInfo alphaInfo = CGImageGetBitmapInfo(imageRef) & kCGBitmapAlphaInfoMask;
+    
+    //Since iOS8 it's not allowed anymore to create contexts with unmultiplied Alpha info
+    if (alphaInfo == kCGImageAlphaLast) {
+        alphaInfo = kCGImageAlphaPremultipliedLast;
+    }
+    if (alphaInfo == kCGImageAlphaFirst) {
+        alphaInfo = kCGImageAlphaPremultipliedFirst;
+    }
+    
+    //reset the bits
+    CGBitmapInfo newBitmapInfo = CGImageGetBitmapInfo(imageRef) & ~kCGBitmapAlphaInfoMask;
+    
+    //set the bits to the new alphaInfo
+    newBitmapInfo |= alphaInfo;
+    
     //create image context from buffer
     CGContextRef ctx = CGBitmapContextCreate(buffer1.data, buffer1.width, buffer1.height,
                                              8, buffer1.rowBytes, CGImageGetColorSpace(imageRef),
-                                             CGImageGetBitmapInfo(imageRef));
+                                             newBitmapInfo);
 
     //apply tint
     if (tintColor && CGColorGetAlpha(tintColor.CGColor) > 0.0f)