iphone image captured from camera rotate -90 degree automatically

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后悔当初
后悔当初 2020-12-01 04:57

Programatically I have fetched image from my camera in my app. It has been fetched nicely but when I shift to another view and dismiss that view at that time my image automa

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  • 2020-12-01 05:35

    you have to use this function to rotate image captured by camera

     - (void)imagePickerController:(UIImagePickerController *)picker
                    didFinishPickingImage:(UIImage *)image
                                        editingInfo:(NSDictionary *)editingInfo
    {
        image = [self scaleAndRotateImage:image];
        [self useImage:image];
        [[picker parentViewController] dismissModalViewControllerAnimated:YES];
    }
    
    
    - (void)scaleAndRotateImage:(UIImage *)image
    {
        int kMaxResolution = 320; // Or whatever
    
        CGImageRef imgRef = image.CGImage;
    
        CGFloat width = CGImageGetWidth(imgRef);
        CGFloat height = CGImageGetHeight(imgRef);
    
        CGAffineTransform transform = CGAffineTransformIdentity;
        CGRect bounds = CGRectMake(0, 0, width, height);
        if (width > kMaxResolution || height > kMaxResolution) {
            CGFloat ratio = width/height;
            if (ratio > 1) {
                bounds.size.width = kMaxResolution;
                bounds.size.height = bounds.size.width / ratio;
            }
            else {
                bounds.size.height = kMaxResolution;
                bounds.size.width = bounds.size.height * ratio;
            }
        }
    
        CGFloat scaleRatio = bounds.size.width / width;
        CGSize imageSize = CGSizeMake(CGImageGetWidth(imgRef), CGImageGetHeight(imgRef));
        CGFloat boundHeight;
        UIImageOrientation orient = image.imageOrientation;
        switch(orient) {
    
            case UIImageOrientationUp: //EXIF = 1
                transform = CGAffineTransformIdentity;
                break;
    
            case UIImageOrientationUpMirrored: //EXIF = 2
                transform = CGAffineTransformMakeTranslation(imageSize.width, 0.0);
                transform = CGAffineTransformScale(transform, -1.0, 1.0);
                break;
    
            case UIImageOrientationDown: //EXIF = 3
                transform = CGAffineTransformMakeTranslation(imageSize.width, imageSize.height);
                transform = CGAffineTransformRotate(transform, M_PI);
                break;
    
            case UIImageOrientationDownMirrored: //EXIF = 4
                transform = CGAffineTransformMakeTranslation(0.0, imageSize.height);
                transform = CGAffineTransformScale(transform, 1.0, -1.0);
                break;
    
            case UIImageOrientationLeftMirrored: //EXIF = 5
                boundHeight = bounds.size.height;
                bounds.size.height = bounds.size.width;
                bounds.size.width = boundHeight;
                transform = CGAffineTransformMakeTranslation(imageSize.height, imageSize.width);
                transform = CGAffineTransformScale(transform, -1.0, 1.0);
                transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
                break;
    
            case UIImageOrientationLeft: //EXIF = 6
                boundHeight = bounds.size.height;
                bounds.size.height = bounds.size.width;
                bounds.size.width = boundHeight;
                transform = CGAffineTransformMakeTranslation(0.0, imageSize.width);
                transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
                break;
    
            case UIImageOrientationRightMirrored: //EXIF = 7
                boundHeight = bounds.size.height;
                bounds.size.height = bounds.size.width;
                bounds.size.width = boundHeight;
                transform = CGAffineTransformMakeScale(-1.0, 1.0);
                transform = CGAffineTransformRotate(transform, M_PI / 2.0);
                break;
    
            case UIImageOrientationRight: //EXIF = 8
                boundHeight = bounds.size.height;
                bounds.size.height = bounds.size.width;
                bounds.size.width = boundHeight;
                transform = CGAffineTransformMakeTranslation(imageSize.height, 0.0);
                transform = CGAffineTransformRotate(transform, M_PI / 2.0);
                break;
    
            default:
                [NSException raise:NSInternalInconsistencyException format:@"Invalid image orientation"];
    
        }
    
        UIGraphicsBeginImageContext(bounds.size);
    
        CGContextRef context = UIGraphicsGetCurrentContext();
    
        if (orient == UIImageOrientationRight || orient == UIImageOrientationLeft) {
            CGContextScaleCTM(context, -scaleRatio, scaleRatio);
            CGContextTranslateCTM(context, -height, 0);
        }
        else {
            CGContextScaleCTM(context, scaleRatio, -scaleRatio);
            CGContextTranslateCTM(context, 0, -height);
        }
    
        CGContextConcatCTM(context, transform);
    
        CGContextDrawImage(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, width, height), imgRef);
        UIImage *imageCopy = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
    
        [self setRotatedImage:imageCopy];
        //return imageCopy;
    }
    
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