fix: rorate issue of heci image

numandev1 · Jun 22, 2021 · 156686c · 156686c
1 parent 1830173
commit 156686c
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diff --git a/ios/Compressor.m b/ios/Compressor.m
@@ -33,6 +33,7 @@ @implementation Compressor
                 reject(@"unsupported_value", @"Unsupported value type.", nil);
                 return;
         }
+        image=[ImageCompressor scaleAndRotateImage:image];
         NSString *outputExtension=[ImageCompressorOptions getOutputInString:options.output];
         UIImage *resizedImage = [ImageCompressor resize:image maxWidth:options.maxWidth maxHeight:options.maxHeight];
         Boolean isBase64=options.returnableOutputType ==rbase64;

diff --git a/ios/Image/ImageCompressor.h b/ios/Image/ImageCompressor.h
@@ -9,4 +9,5 @@
 
 + (UIImage *)resize:(UIImage *)image maxWidth:(int)maxWidth maxHeight:(int)maxHeight;
 + (NSString *)compress:(UIImage *)image output:(enum OutputType)output quality:(float)quality outputExtension:(NSString*)outputExtension isBase64:(Boolean)isBase64;
++ (UIImage *)scaleAndRotateImage:(UIImage *)image;
 @end
diff --git a/ios/Image/ImageCompressor.m b/ios/Image/ImageCompressor.m
@@ -135,4 +135,83 @@ + (NSString *)generateCacheFilePath:(NSString *)extension{
     return filePath;
 }
 
++(UIImage *)scaleAndRotateImage:(UIImage *)image{
+        // No-op if the orientation is already correct
+        if (image.imageOrientation == UIImageOrientationUp) return image;
+
+        // We need to calculate the proper transformation to make the image upright.
+        // We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
+        CGAffineTransform transform = CGAffineTransformIdentity;
+
+        switch (image.imageOrientation) {
+            case UIImageOrientationDown:
+            case UIImageOrientationDownMirrored:
+                transform = CGAffineTransformTranslate(transform, image.size.width, image.size.height);
+                transform = CGAffineTransformRotate(transform, M_PI);
+                break;
+
+            case UIImageOrientationLeft:
+            case UIImageOrientationLeftMirrored:
+                transform = CGAffineTransformTranslate(transform, image.size.width, 0);
+                transform = CGAffineTransformRotate(transform, M_PI_2);
+                break;
+
+            case UIImageOrientationRight:
+            case UIImageOrientationRightMirrored:
+                transform = CGAffineTransformTranslate(transform, 0, image.size.height);
+                transform = CGAffineTransformRotate(transform, -M_PI_2);
+                break;
+            case UIImageOrientationUp:
+            case UIImageOrientationUpMirrored:
+                break;
+        }
+
+        switch (image.imageOrientation) {
+            case UIImageOrientationUpMirrored:
+            case UIImageOrientationDownMirrored:
+                transform = CGAffineTransformTranslate(transform, image.size.width, 0);
+                transform = CGAffineTransformScale(transform, -1, 1);
+                break;
+
+            case UIImageOrientationLeftMirrored:
+            case UIImageOrientationRightMirrored:
+                transform = CGAffineTransformTranslate(transform, image.size.height, 0);
+                transform = CGAffineTransformScale(transform, -1, 1);
+                break;
+            case UIImageOrientationUp:
+            case UIImageOrientationDown:
+            case UIImageOrientationLeft:
+            case UIImageOrientationRight:
+                break;
+        }
+
+        // Now we draw the underlying CGImage into a new context, applying the transform
+        // calculated above.
+        CGContextRef ctx = CGBitmapContextCreate(NULL, image.size.width, image.size.height,
+                                                 CGImageGetBitsPerComponent(image.CGImage), 0,
+                                                 CGImageGetColorSpace(image.CGImage),
+                                                 CGImageGetBitmapInfo(image.CGImage));
+        CGContextConcatCTM(ctx, transform);
+        switch (image.imageOrientation) {
+            case UIImageOrientationLeft:
+            case UIImageOrientationLeftMirrored:
+            case UIImageOrientationRight:
+            case UIImageOrientationRightMirrored:
+                // Grr...
+                CGContextDrawImage(ctx, CGRectMake(0,0,image.size.height,image.size.width), image.CGImage);
+                break;
+
+            default:
+                CGContextDrawImage(ctx, CGRectMake(0,0,image.size.width,image.size.height), image.CGImage);
+                break;
+        }
+
+        // And now we just create a new UIImage from the drawing context
+        CGImageRef cgimg = CGBitmapContextCreateImage(ctx);
+        UIImage *img = [UIImage imageWithCGImage:cgimg];
+        CGContextRelease(ctx);
+        CGImageRelease(cgimg);
+        return img;
+}
+
 @end