From 10d7d883103cab0a866380de833f496532d1d05d Mon Sep 17 00:00:00 2001
From: Mattt Thompson <m@mattt.me>
Date: Tue, 18 Jun 2013 08:56:23 -0700
Subject: [PATCH] Adding automaticallyInflatesResponseImage property to
 AFImageRequestOperation

Falling back on initWithData:scale: initialization when available (iOS > 5)
---
 AFNetworking/AFImageRequestOperation.h |  5 ++++
 AFNetworking/AFImageRequestOperation.m | 39 ++++++++++++++++++--------
 2 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/AFNetworking/AFImageRequestOperation.h b/AFNetworking/AFImageRequestOperation.h
index f0bee4b..d5e6596 100644
--- a/AFNetworking/AFImageRequestOperation.h
+++ b/AFNetworking/AFImageRequestOperation.h
@@ -65,6 +65,11 @@
  The scale factor used when interpreting the image data to construct `responseImage`. Specifying a scale factor of 1.0 results in an image whose size matches the pixel-based dimensions of the image. Applying a different scale factor changes the size of the image as reported by the size property. This is set to the value of scale of the main screen by default, which automatically scales images for retina displays, for instance.
  */
 @property (nonatomic, assign) CGFloat imageScale;
+
+/**
+ Whether to automatically inflate response image data for compressed formats (such as PNG or JPEG). Enabling this can significantly improve drawing performance on iOS when used with `setCompletionBlockWithSuccess:failure:`, as it allows a bitmap representation to be constructed in the background rather than on the main thread. `YES` by default.
+ */
+@property (nonatomic, assign) BOOL automaticallyInflatesResponseImage;
 #endif
 
 /**
diff --git a/AFNetworking/AFImageRequestOperation.m b/AFNetworking/AFImageRequestOperation.m
index c39c149..2154124 100644
--- a/AFNetworking/AFImageRequestOperation.m
+++ b/AFNetworking/AFImageRequestOperation.m
@@ -35,6 +35,15 @@ static dispatch_queue_t image_request_operation_processing_queue() {
 #if defined(__IPHONE_OS_VERSION_MIN_REQUIRED)
 #import <CoreGraphics/CoreGraphics.h>
 
+static UIImage * AFImageWithDataAtScale(NSData *data, CGFloat scale) {
+    if ([UIImage instancesRespondToSelector:@selector(initWithData:scale:)]) {
+        return [[UIImage alloc] initWithData:data scale:scale];
+    } else {
+        UIImage *image = [[UIImage alloc] initWithData:data];
+        return [[UIImage alloc] initWithCGImage:[image CGImage] scale:scale orientation:image.imageOrientation];
+    }
+}
+
 static UIImage * AFInflatedImageFromResponseWithDataAtScale(NSHTTPURLResponse *response, NSData *data, CGFloat scale) {
     if (!data || [data length] == 0) {
         return nil;
@@ -50,9 +59,10 @@ static UIImage * AFInflatedImageFromResponseWithDataAtScale(NSHTTPURLResponse *r
     } else if ([contentTypes containsObject:@"image/jpeg"]) {
         imageRef = CGImageCreateWithJPEGDataProvider(dataProvider, NULL, true, kCGRenderingIntentDefault);
     } else {
-        UIImage *image = [[UIImage alloc] initWithData:data scale:scale];
+        UIImage *image = AFImageWithDataAtScale(data, scale);
         if (image.images) {
             CGDataProviderRelease(dataProvider);
+            
             return image;
         }
         
@@ -68,17 +78,19 @@ static UIImage * AFInflatedImageFromResponseWithDataAtScale(NSHTTPURLResponse *r
     size_t width = CGImageGetWidth(imageRef);
     size_t height = CGImageGetHeight(imageRef);
     size_t bitsPerComponent = CGImageGetBitsPerComponent(imageRef);
-    size_t bytesPerRow = CGImageGetBytesPerRow(imageRef);
+    size_t bytesPerRow = NULL; // CGImageGetBytesPerRow() calculates incorrectly in iOS 5.0, so defer to CGBitmapContextCreate()
     CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
     CGBitmapInfo bitmapInfo = CGImageGetBitmapInfo(imageRef);
 
-    int alpha = (bitmapInfo & kCGBitmapAlphaInfoMask);
-    if (alpha == kCGImageAlphaNone && CGColorSpaceGetNumberOfComponents(colorSpace) == 3) {
-        bitmapInfo &= ~kCGBitmapAlphaInfoMask;
-        bitmapInfo |= kCGImageAlphaNoneSkipFirst;
-    } else if (!(alpha == kCGImageAlphaNoneSkipFirst || alpha == kCGImageAlphaNoneSkipLast) && CGColorSpaceGetNumberOfComponents(colorSpace) == 3) {
-        bitmapInfo &= ~kCGBitmapAlphaInfoMask;
-        bitmapInfo |= kCGImageAlphaPremultipliedFirst;
+    if (CGColorSpaceGetNumberOfComponents(colorSpace) == 3) {
+        int alpha = (bitmapInfo & kCGBitmapAlphaInfoMask);
+        if (alpha == kCGImageAlphaNone) {
+            bitmapInfo &= ~kCGBitmapAlphaInfoMask;
+            bitmapInfo |= kCGImageAlphaNoneSkipFirst;
+        } else if (!(alpha == kCGImageAlphaNoneSkipFirst || alpha == kCGImageAlphaNoneSkipLast)) {
+            bitmapInfo &= ~kCGBitmapAlphaInfoMask;
+            bitmapInfo |= kCGImageAlphaPremultipliedFirst;
+        }
     }
 
     CGContextRef context = CGBitmapContextCreate(NULL, width, height, bitsPerComponent, bytesPerRow, colorSpace, bitmapInfo);
@@ -88,7 +100,7 @@ static UIImage * AFInflatedImageFromResponseWithDataAtScale(NSHTTPURLResponse *r
     if (!context) {
         CGImageRelease(imageRef);
 
-        return [[UIImage alloc] initWithData:data scale:scale];
+        return [[UIImage alloc] initWithData:data];
     }
 
     CGRect rect = CGRectMake(0.0f, 0.0f, width, height);
@@ -214,6 +226,7 @@ static UIImage * AFInflatedImageFromResponseWithDataAtScale(NSHTTPURLResponse *r
 
 #if defined(__IPHONE_OS_VERSION_MIN_REQUIRED)
     self.imageScale = [[UIScreen mainScreen] scale];
+    self.automaticallyInflatesResponseImage = YES;
 #endif
 
     return self;
@@ -223,7 +236,11 @@ static UIImage * AFInflatedImageFromResponseWithDataAtScale(NSHTTPURLResponse *r
 #if defined(__IPHONE_OS_VERSION_MIN_REQUIRED)
 - (UIImage *)responseImage {
     if (!_responseImage && [self.responseData length] > 0 && [self isFinished]) {
-        self.responseImage = AFInflatedImageFromResponseWithDataAtScale(self.response, self.responseData, self.imageScale);
+        if (self.automaticallyInflatesResponseImage) {
+            self.responseImage = AFInflatedImageFromResponseWithDataAtScale(self.response, self.responseData, self.imageScale);
+        } else {
+            self.responseImage = AFImageWithDataAtScale(self.responseData, self.imageScale);
+        }
     }
 
     return _responseImage;