Merge pull request #764 from n13/master

support for image orientation

SDWebImage/UIImage+MultiFormat.m

@@ -9,6 +9,7 @@
 #import "UIImage+MultiFormat.h"
 #import "UIImage+GIF.h"
 #import "NSData+ImageContentType.h"
+#import <ImageIO/ImageIO.h>
 
 #ifdef SD_WEBP
 #import "UIImage+WebP.h"
@@ -30,10 +31,82 @@
 #endif
     else {
         image = [[UIImage alloc] initWithData:data];
+        UIImageOrientation orientation = [self sd_imageOrientationFromImageData:data];
+        if (orientation != UIImageOrientationUp) {
+            image = [UIImage imageWithCGImage:image.CGImage
+                                        scale:image.scale
+                                  orientation:orientation];
+        }
     }
 
 
     return image;
 }
 
+
++(UIImageOrientation)sd_imageOrientationFromImageData:(NSData *)imageData {
+    UIImageOrientation result = UIImageOrientationUp;
+    CGImageSourceRef imageSource = CGImageSourceCreateWithData((__bridge CFDataRef)imageData, NULL);
+    CFDictionaryRef properties = CGImageSourceCopyPropertiesAtIndex(imageSource, 0, NULL);
+    if (properties) {
+        CFTypeRef val;
+        int exifOrientation;
+        val = CFDictionaryGetValue(properties, kCGImagePropertyOrientation);
+        if (val) {
+            CFNumberGetValue(val, kCFNumberIntType, &exifOrientation);
+            result = [self sd_exifOrientationToiOSOrientation:exifOrientation];
+        } // else - if it's not set it remains at up
+        CFRelease((CFTypeRef) properties);
+    } else {
+        //NSLog(@"NO PROPERTIES, FAIL");
+    }
+    CFRelease(imageSource);
+    return result;
+}
+
+#pragma EXIF orientation tag converter
+// Convert an EXIF image orientation to an iOS one.
+// reference see here: http://sylvana.net/jpegcrop/exif_orientation.html
++ (UIImageOrientation) sd_exifOrientationToiOSOrientation:(int)exifOrientation {
+    UIImageOrientation orientation = UIImageOrientationUp;
+    switch (exifOrientation) {
+        case 1:
+            orientation = UIImageOrientationUp;
+            break;
+
+        case 3:
+            orientation = UIImageOrientationDown;
+            break;
+
+        case 8:
+            orientation = UIImageOrientationLeft;
+            break;
+
+        case 6:
+            orientation = UIImageOrientationRight;
+            break;
+
+        case 2:
+            orientation = UIImageOrientationUpMirrored;
+            break;
+
+        case 4:
+            orientation = UIImageOrientationDownMirrored;
+            break;
+
+        case 5:
+            orientation = UIImageOrientationLeftMirrored;
+            break;
+
+        case 7:
+            orientation = UIImageOrientationRightMirrored;
+            break;
+        default:
+            break;
+    }
+    return orientation;
+}
+
+
+
 @end