上传后的 iOS UIImagePickerController 结果图像方向

iOS UIImagePickerController result image orientation after upload

提问人:james 提问时间:3/25/2011 最后编辑:Alokjames 更新时间:10/6/2020 访问量:145551

问:

我正在 iOS 3.1.3 iPhone 上测试我的 iPhone 应用程序。我正在使用以下命令选择/捕获图像:UIImagePickerController

UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
[imagePicker setSourceType:UIImagePickerControllerSourceTypeCamera];
[imagePicker setDelegate:self];
[self.navigationController presentModalViewController:imagePicker animated:YES];
[imagePicker release];



- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    self.image = [info objectForKey:UIImagePickerControllerOriginalImage];
    imageView.image = self.image;
    [self.navigationController dismissModalViewControllerAnimated:YES];
    submitButton.enabled = YES;
}

然后,我在某个时候使用 ASI 类将其发送到我的 Web 服务器:

ASIFormDataRequest *request = [ASIFormDataRequest requestWithURL:[NSURL URLWithString:@"http://example.com/myscript.php"]];
[request setDelegate:self];
[request setStringEncoding:NSUTF8StringEncoding];
[request setShouldContinueWhenAppEntersBackground:YES];
//other post keys/values
[request setFile:UIImageJPEGRepresentation(self.image, 100.0f) withFileName:[NSString stringWithFormat:@"%d.jpg", [[NSDate date] timeIntervalSinceNow]] andContentType:@"image/jpg" forKey:@"imageFile"];
[request startAsynchronous];

问题: 当我拿着iPhone横向拍照时,图像会上传到服务器,并像您期望的那样查看。当拿着手机纵向拍照时,图像会上传并查看,因为它已经旋转了 90 度。

我的应用程序设置为仅在纵向模式(颠倒和常规)下工作。

如何使图片在上传后始终显示正确的方向?

图像在UIImageView中显示是正确的(直接在拍照后),但在服务器上查看则相反。

iOS iPhone Cocoa-Touch UIImition UIImagePickerController

评论


答:

515赞 Anomie 3/25/2011 #1

A 有一个属性,它指示和其他消费者旋转原始图像数据。此标志很有可能被保存到上传的 jpeg 图像中的 exif 数据中,但您用于查看它的程序不遵循该标志。UIImageimageOrientationUIImageViewUIImage

要在上传时正确旋转显示,可以使用如下类别:UIImage

UIImage+fixOrientation.h

@interface UIImage (fixOrientation)

- (UIImage *)fixOrientation;

@end

UIImage+fixOrientation.m

@implementation UIImage (fixOrientation)

- (UIImage *)fixOrientation {

    // No-op if the orientation is already correct
    if (self.imageOrientation == UIImageOrientationUp) return self;

    // 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 (self.imageOrientation) {
        case UIImageOrientationDown:
        case UIImageOrientationDownMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, self.size.height);
            transform = CGAffineTransformRotate(transform, M_PI);
            break;

        case UIImageOrientationLeft:
        case UIImageOrientationLeftMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, 0);
            transform = CGAffineTransformRotate(transform, M_PI_2);
            break;

        case UIImageOrientationRight:
        case UIImageOrientationRightMirrored:
            transform = CGAffineTransformTranslate(transform, 0, self.size.height);
            transform = CGAffineTransformRotate(transform, -M_PI_2);
            break;
        case UIImageOrientationUp:
        case UIImageOrientationUpMirrored:
            break;
    }

    switch (self.imageOrientation) {
        case UIImageOrientationUpMirrored:
        case UIImageOrientationDownMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, 0);
            transform = CGAffineTransformScale(transform, -1, 1);
            break;

        case UIImageOrientationLeftMirrored:
        case UIImageOrientationRightMirrored:
            transform = CGAffineTransformTranslate(transform, self.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, self.size.width, self.size.height,
                                             CGImageGetBitsPerComponent(self.CGImage), 0,
                                             CGImageGetColorSpace(self.CGImage),
                                             CGImageGetBitmapInfo(self.CGImage));
    CGContextConcatCTM(ctx, transform);
    switch (self.imageOrientation) {
        case UIImageOrientationLeft:
        case UIImageOrientationLeftMirrored:
        case UIImageOrientationRight:
        case UIImageOrientationRightMirrored:
            // Grr...
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.height,self.size.width), self.CGImage);
            break;

        default:
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.width,self.size.height), self.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

评论

9赞 james 3/26/2011
谢谢,工作完美。直到现在,从未使用过类别或理解它们!
1赞 Darkshore Grouper 8/22/2012
@Anomie 我很难解释你刚才让我有多高兴。你的回答挽救了我的一天。谢谢。
3赞 Laxmi Lal Menaria 12/18/2012
我尝试了相同的方法,效果很好,但旋转 2-3 秒需要 3264*2448 分辨率的图像。因此,请建议改进版本。
3赞 pojomx 4/3/2013
我认为 stackoverflow.com/questions/8915630/...是一个更好的答案
2赞 Gallymon 11/29/2013
这里还有另一个解决方案(与这个问题非常相似),其中包括对实际发生的事情的冗长讨论。
243赞 an0 5/16/2012 #2

我想出了一个更简单的方法:

- (UIImage *)normalizedImage {
    if (self.imageOrientation == UIImageOrientationUp) return self; 

    UIGraphicsBeginImageContextWithOptions(self.size, NO, self.scale);
    [self drawInRect:(CGRect){0, 0, self.size}];
    UIImage *normalizedImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return normalizedImage;
}

顺便说一句:@Anomie 的代码没有考虑在内,因此不适用于 2x 图像。scale

评论

0赞 Dejell 9/5/2012
如何在代码中使用它?我有这个:UIImageJPEGRepresentation(image, 90);其中图像是 UIImage
2赞 an0 9/5/2012
@Odelya 将此方法添加到 UIImage 类别,然后调用 [image normalizedImage]。或者直接使用该方法的代码,方法是替换为 UIImage 对象。self
1赞 Dejell 3/3/2013
@an0 该方法大约需要一秒钟,这会消耗时间。有没有办法改进它?
1赞 chrisben 8/29/2013
谢谢你。从我的测试来看,这种方法似乎比所选答案快一点,在我的 iphone4 上大约是 20%。
7赞 Gallymon 11/29/2013
这里还有另一种解决这个问题的方法,以及对正在发生的事情的冗长解释。
6赞 Shekhar Gupta 3/9/2013 #3

这是我发现的解决方向问题的方法

UIImage *initialImage = [info objectForKey:@"UIImagePickerControllerOriginalImage"];
NSData *data = UIImagePNGRepresentation(self.initialImage);

UIImage *tempImage = [UIImage imageWithData:data];
UIImage *fixedOrientationImage = [UIImage imageWithCGImage:tempImage.CGImage
                                     scale:initialImage.scale
                               orientation:self.initialImage.imageOrientation];
initialImage = fixedOrientationImage;

编辑:

UIImage *initialImage = [info objectForKey:@"UIImagePickerControllerOriginalImage"];
NSData *data = UIImagePNGRepresentation(self.initialImage);

initialImage = [UIImage imageWithCGImage:[UIImage imageWithData:data].CGImage
                                                     scale:initialImage.scale
                                               orientation:self.initialImage.imageOrientation];

评论

2赞 lxcid 8/27/2013
图像到PNG之间的转换过多,导致成本太高。@an0答案更好。
12赞 Erroneous 10/14/2013 #4

我在设计拍照的应用程序时使用了这个页面,我发现以下方法将纠正方向并使用比以前的答案更少的内存和处理器:

CGImageRef cgRef = image.CGImage;
image = [[UIImage alloc] initWithCGImage:cgRef scale:1.0 orientation:UIImageOrientationUp];

这基本上只是用新的方向重新包装实际的图像数据。我使用的是 @an0 的代码,但它在内存中生成了一个新图像,这可能会对您可能从相机获得的 3264x2448 图像造成负担。

评论

1赞 Jawad Al Shaikh 4/28/2014
我在 iPhone 7.1s 上使用 iOS 5 测试了这个答案,但它不起作用,其中 Windows 机器 [MS-Paint、Win photo Viewer] 和 UIImageView 显示图像与原始方向为 90 度!请注意,使用默认的相机触摸按钮拍摄的图像,而不是调高音量。
3赞 hamsterdam 5/30/2014
似乎这只是改变了方向标志......需要旋转实际位
11赞 Jon 3/5/2014 #5

如果启用编辑,则编辑后的图像(而不是原始图像)将按预期定向:

UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
imagePickerController.allowsEditing = YES;
// set delegate and present controller

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    UIImage *photo = [info valueForKey:UIImagePickerControllerEditedImage];
    // do whatever
}

启用编辑允许用户在点击“使用照片”之前调整图像大小和移动图像

评论

0赞 King-Wizard 3/16/2015
不幸的是,此解决方案无法水平翻转图像,甚至不允许编辑。
4赞 user3000868 12/16/2015
有效,但强制用户将图像裁剪为正方形,除非您想添加更多代码以允许可变裁剪大小
25赞 MetalHeart2003 11/23/2014 #6

在 Swift ;)

更新 SWIFT 3.0 :D

func sFunc_imageFixOrientation(img:UIImage) -> UIImage {


    // No-op if the orientation is already correct
    if (img.imageOrientation == UIImageOrientation.up) {
        return img;
    }
    // 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.
    var transform:CGAffineTransform = CGAffineTransform.identity

    if (img.imageOrientation == UIImageOrientation.down
        || img.imageOrientation == UIImageOrientation.downMirrored) {

        transform = transform.translatedBy(x: img.size.width, y: img.size.height)
        transform = transform.rotated(by: CGFloat(M_PI))
    }

    if (img.imageOrientation == UIImageOrientation.left
        || img.imageOrientation == UIImageOrientation.leftMirrored) {

        transform = transform.translatedBy(x: img.size.width, y: 0)
        transform = transform.rotated(by: CGFloat(M_PI_2))
    }

    if (img.imageOrientation == UIImageOrientation.right
        || img.imageOrientation == UIImageOrientation.rightMirrored) {

        transform = transform.translatedBy(x: 0, y: img.size.height);
        transform = transform.rotated(by: CGFloat(-M_PI_2));
    }

    if (img.imageOrientation == UIImageOrientation.upMirrored
        || img.imageOrientation == UIImageOrientation.downMirrored) {

        transform = transform.translatedBy(x: img.size.width, y: 0)
        transform = transform.scaledBy(x: -1, y: 1)
    }

    if (img.imageOrientation == UIImageOrientation.leftMirrored
        || img.imageOrientation == UIImageOrientation.rightMirrored) {

        transform = transform.translatedBy(x: img.size.height, y: 0);
        transform = transform.scaledBy(x: -1, y: 1);
    }


    // Now we draw the underlying CGImage into a new context, applying the transform
    // calculated above.
    let ctx:CGContext = CGContext(data: nil, width: Int(img.size.width), height: Int(img.size.height),
                                  bitsPerComponent: img.cgImage!.bitsPerComponent, bytesPerRow: 0,
                                  space: img.cgImage!.colorSpace!,
                                  bitmapInfo: img.cgImage!.bitmapInfo.rawValue)!

    ctx.concatenate(transform)


    if (img.imageOrientation == UIImageOrientation.left
        || img.imageOrientation == UIImageOrientation.leftMirrored
        || img.imageOrientation == UIImageOrientation.right
        || img.imageOrientation == UIImageOrientation.rightMirrored
        ) {


        ctx.draw(img.cgImage!, in: CGRect(x:0,y:0,width:img.size.height,height:img.size.width))

    } else {
        ctx.draw(img.cgImage!, in: CGRect(x:0,y:0,width:img.size.width,height:img.size.height))
    }


    // And now we just create a new UIImage from the drawing context
    let cgimg:CGImage = ctx.makeImage()!
    let imgEnd:UIImage = UIImage(cgImage: cgimg)

    return imgEnd
}

评论

0赞 SirNod 3/15/2015
经过数周的苦苦挣扎并尝试了其他几种解决方案,这个解决方案最终完美运行。如果我能投+10票,我会的。谢谢。:)
0赞 TimWhiting 4/1/2015
@MetalHeart2003这种方法大量增加了我图像的文件大小,我的从 200kb 增加到 4mb,有什么方法可以阻止这种情况发生吗?
2赞 Richard Venable 5/14/2015
@TimWhiting听起来像是从压缩图像开始的。但是这种方法会在没有任何压缩的情况下重新绘制旋转的图像。之后可以使用 UIImageJPEGRepresentation() 重新压缩位图图像
129赞 prajna 1/5/2015 #7

以下是 @an0 的答案的 Swift 版本:

func normalizedImage() -> UIImage {

  if (self.imageOrientation == UIImageOrientation.Up) { 
      return self;
  }

  UIGraphicsBeginImageContextWithOptions(self.size, false, self.scale);
  let rect = CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height)
  self.drawInRect(rect)

  let normalizedImage : UIImage = UIGraphicsGetImageFromCurrentImageContext()
  UIGraphicsEndImageContext();
  return normalizedImage;
}

同样在更通用的功能中:

func fixOrientation(img:UIImage) -> UIImage {

  if (img.imageOrientation == UIImageOrientation.Up) { 
      return img;
  }

  UIGraphicsBeginImageContextWithOptions(img.size, false, img.scale);
  let rect = CGRect(x: 0, y: 0, width: img.size.width, height: img.size.height)
  img.drawInRect(rect)

  let normalizedImage : UIImage = UIGraphicsGetImageFromCurrentImageContext()
  UIGraphicsEndImageContext();
  return normalizedImage;

}

Swift 3 版本:

func fixOrientation(img: UIImage) -> UIImage {
    if (img.imageOrientation == .up) {
        return img
    }

    UIGraphicsBeginImageContextWithOptions(img.size, false, img.scale)
    let rect = CGRect(x: 0, y: 0, width: img.size.width, height: img.size.height)
    img.draw(in: rect)

    let normalizedImage = UIGraphicsGetImageFromCurrentImageContext()!
    UIGraphicsEndImageContext()

    return normalizedImage
}

评论

10赞 sudo make install 5/31/2015
很少需要一直滚动到底部才能获得最佳答案。+1!
0赞 alex 10/23/2015
我应该在哪里使用 fixOrientation?我有一个 saveImage 函数,我应该在那里使用它还是在我的 imageHolder.image 上使用它?
0赞 prajna 10/26/2015
如果你想使用上面更通用的函数,那么是的,你可以在你的saveImage函数中使用它。只需将 fixOrientation 传递给您的 UIImage 对象,它就会返回您传递到其中的 UIImage 的正确方向版本。
1赞 Shadros 6/7/2018
感谢 Swift 3 版本
3赞 jake1981 6/25/2015 #8

这是 swift 的 UIImage 扩展:

extension UIImage {

    func fixOrientation() -> UIImage {

        // No-op if the orientation is already correct
        if ( self.imageOrientation == UIImageOrientation.Up ) {
            return self;
        }

        // 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.
        var transform: CGAffineTransform = CGAffineTransformIdentity

        if ( self.imageOrientation == UIImageOrientation.Down || self.imageOrientation == UIImageOrientation.DownMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, self.size.height)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI))
        }

        if ( self.imageOrientation == UIImageOrientation.Left || self.imageOrientation == UIImageOrientation.LeftMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI_2))
        }

        if ( self.imageOrientation == UIImageOrientation.Right || self.imageOrientation == UIImageOrientation.RightMirrored ) {
            transform = CGAffineTransformTranslate(transform, 0, self.size.height);
            transform = CGAffineTransformRotate(transform,  CGFloat(-M_PI_2));
        }

        if ( self.imageOrientation == UIImageOrientation.UpMirrored || self.imageOrientation == UIImageOrientation.DownMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformScale(transform, -1, 1)
        }

        if ( self.imageOrientation == UIImageOrientation.LeftMirrored || self.imageOrientation == UIImageOrientation.RightMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.height, 0);
            transform = CGAffineTransformScale(transform, -1, 1);
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        var ctx: CGContextRef = CGBitmapContextCreate(nil, Int(self.size.width), Int(self.size.height),
            CGImageGetBitsPerComponent(self.CGImage), 0,
            CGImageGetColorSpace(self.CGImage),
            CGImageGetBitmapInfo(self.CGImage));

        CGContextConcatCTM(ctx, transform)

        if ( self.imageOrientation == UIImageOrientation.Left ||
            self.imageOrientation == UIImageOrientation.LeftMirrored ||
            self.imageOrientation == UIImageOrientation.Right ||
            self.imageOrientation == UIImageOrientation.RightMirrored ) {
                CGContextDrawImage(ctx, CGRectMake(0,0,self.size.height,self.size.width), self.CGImage)
        } else {
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.width,self.size.height), self.CGImage)
        }

        // And now we just create a new UIImage from the drawing context and return it
        return UIImage(CGImage: CGBitmapContextCreateImage(ctx))!
    }
}

基于MetalHeart2003的早期作品。

44赞 Sourabh Sharma 11/2/2015 #9

Swift 3.1 的解决方案,用于从相机捕获图像时的方向问题。

我已经更新了 Jake 和 Metal Heart 给出的解决方案

UIImage 扩展

//MARK:- Image Orientation fix

extension UIImage {

    func fixOrientation() -> UIImage {

        // No-op if the orientation is already correct
        if ( self.imageOrientation == UIImageOrientation.up ) {
            return self;
        }

        // 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.
        var transform: CGAffineTransform = CGAffineTransform.identity

        if ( self.imageOrientation == UIImageOrientation.down || self.imageOrientation == UIImageOrientation.downMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: self.size.height)
            transform = transform.rotated(by: CGFloat(Double.pi))
        }

        if ( self.imageOrientation == UIImageOrientation.left || self.imageOrientation == UIImageOrientation.leftMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: 0)
            transform = transform.rotated(by: CGFloat(Double.pi / 2.0))
        }

        if ( self.imageOrientation == UIImageOrientation.right || self.imageOrientation == UIImageOrientation.rightMirrored ) {
            transform = transform.translatedBy(x: 0, y: self.size.height);
            transform = transform.rotated(by: CGFloat(-Double.pi / 2.0));
        }

        if ( self.imageOrientation == UIImageOrientation.upMirrored || self.imageOrientation == UIImageOrientation.downMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: 0)
            transform = transform.scaledBy(x: -1, y: 1)
        }

        if ( self.imageOrientation == UIImageOrientation.leftMirrored || self.imageOrientation == UIImageOrientation.rightMirrored ) {
            transform = transform.translatedBy(x: self.size.height, y: 0);
            transform = transform.scaledBy(x: -1, y: 1);
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        let ctx: CGContext = CGContext(data: nil, width: Int(self.size.width), height: Int(self.size.height),
                                                      bitsPerComponent: self.cgImage!.bitsPerComponent, bytesPerRow: 0,
                                                      space: self.cgImage!.colorSpace!,
                                                      bitmapInfo: self.cgImage!.bitmapInfo.rawValue)!;

        ctx.concatenate(transform)

        if ( self.imageOrientation == UIImageOrientation.left ||
            self.imageOrientation == UIImageOrientation.leftMirrored ||
            self.imageOrientation == UIImageOrientation.right ||
            self.imageOrientation == UIImageOrientation.rightMirrored ) {
            ctx.draw(self.cgImage!, in: CGRect(x: 0,y: 0,width: self.size.height,height: self.size.width))
        } else {
            ctx.draw(self.cgImage!, in: CGRect(x: 0,y: 0,width: self.size.width,height: self.size.height))
        }

        // And now we just create a new UIImage from the drawing context and return it
        return UIImage(cgImage: ctx.makeImage()!)
    }
}

斯威夫特 2.0

//MARK:- Image Orientation fix

extension UIImage {

    func fixOrientation() -> UIImage {

        // No-op if the orientation is already correct
        if ( self.imageOrientation == UIImageOrientation.Up ) {
            return self;
        }

        // 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.
        var transform: CGAffineTransform = CGAffineTransformIdentity

        if ( self.imageOrientation == UIImageOrientation.Down || self.imageOrientation == UIImageOrientation.DownMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, self.size.height)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI))
        }

        if ( self.imageOrientation == UIImageOrientation.Left || self.imageOrientation == UIImageOrientation.LeftMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI_2))
        }

        if ( self.imageOrientation == UIImageOrientation.Right || self.imageOrientation == UIImageOrientation.RightMirrored ) {
            transform = CGAffineTransformTranslate(transform, 0, self.size.height);
            transform = CGAffineTransformRotate(transform,  CGFloat(-M_PI_2));
        }

        if ( self.imageOrientation == UIImageOrientation.UpMirrored || self.imageOrientation == UIImageOrientation.DownMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformScale(transform, -1, 1)
        }

        if ( self.imageOrientation == UIImageOrientation.LeftMirrored || self.imageOrientation == UIImageOrientation.RightMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.height, 0);
            transform = CGAffineTransformScale(transform, -1, 1);
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        let ctx: CGContextRef = CGBitmapContextCreate(nil, Int(self.size.width), Int(self.size.height),
            CGImageGetBitsPerComponent(self.CGImage), 0,
            CGImageGetColorSpace(self.CGImage),
            CGImageGetBitmapInfo(self.CGImage).rawValue)!;

        CGContextConcatCTM(ctx, transform)

        if ( self.imageOrientation == UIImageOrientation.Left ||
            self.imageOrientation == UIImageOrientation.LeftMirrored ||
            self.imageOrientation == UIImageOrientation.Right ||
            self.imageOrientation == UIImageOrientation.RightMirrored ) {
                CGContextDrawImage(ctx, CGRectMake(0,0,self.size.height,self.size.width), self.CGImage)
        } else {
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.width,self.size.height), self.CGImage)
        }

        // And now we just create a new UIImage from the drawing context and return it
        return UIImage(CGImage: CGBitmapContextCreateImage(ctx)!)
    }
}

在代码中使用此 UIImage 扩展:

让 fixOrientationImage=chosenImage.fixOrientation()

将它放在图像选择器的委托方法中,如下所示

斯威夫特 3.1

//MARK: Image Picker Delegates
    func imagePickerController(
        _ picker: UIImagePickerController,
        didFinishPickingMediaWithInfo info: [String : Any]){
        let chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage
        profileImg.contentMode = .scaleAspectFill
        let fixOrientationImage=chosenImage.fixOrientation()
        profileImg.image = fixOrientationImage

        dismiss(animated: true, completion: nil)
    }

斯威夫特 2.0

//MARK: Image Picker Delegates
    func imagePickerController(
        picker: UIImagePickerController,
        didFinishPickingMediaWithInfo info: [String : AnyObject])
    {
        let chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage
        profileImg.contentMode = .ScaleAspectFill
        **//Fix the image orientation**
         let fixOrientationImage=chosenImage.fixOrientation()
        profileImg.image = fixOrientationImage

        dismissViewControllerAnimated(true, completion: nil)
    }

评论

3赞 kevinrodriguez-io 11/24/2015
谢谢,这对我帮助很大。
0赞 Tony Fung 3/14/2017
它的工作。但我想知道是否有任何方法可以避免调用与 CG 相关的 API,因为这会导致大量内存分配。只有当我们不再保留 UIImage 时,它才会发布。
1赞 MMP 10/29/2017
在iOS 10之前,这一直工作正常。在iOS 11中,执行此操作后,我得到了一个黑色图像作为回报。不过,我做了一个小改动(用 Double.pi 替换M_PI)。我正在将 XCode 9 与 Swift 3.2 一起使用。
3赞 elegance66 3/14/2016 #10

这是 Swift 2 中基于 @Anomie 接受的答案的 UIImage 扩展。它使用更清晰的开关外壳。它还考虑了 返回的可选值。CGBitmapContextCreateImage()

extension UIImage {
    func rotateImageByOrientation() -> UIImage {
        // No-op if the orientation is already correct
        guard self.imageOrientation != .Up else {
            return self
        }

        // 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.
        var transform = CGAffineTransformIdentity;

        switch (self.imageOrientation) {
        case .Down, .DownMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, self.size.height)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI))

        case .Left, .LeftMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI_2))

        case .Right, .RightMirrored:
            transform = CGAffineTransformTranslate(transform, 0, self.size.height)
            transform = CGAffineTransformRotate(transform, CGFloat(-M_PI_2))

        default:
            break
        }

        switch (self.imageOrientation) {
        case .UpMirrored, .DownMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformScale(transform, -1, 1)

        case .LeftMirrored, .RightMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.height, 0)
            transform = CGAffineTransformScale(transform, -1, 1)

        default:
            break
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        let ctx = CGBitmapContextCreate(nil, Int(self.size.width), Int(self.size.height),
            CGImageGetBitsPerComponent(self.CGImage), 0,
            CGImageGetColorSpace(self.CGImage),
            CGImageGetBitmapInfo(self.CGImage).rawValue)
        CGContextConcatCTM(ctx, transform)
        switch (self.imageOrientation) {
        case .Left, .LeftMirrored, .Right, .RightMirrored:
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.height,self.size.width), self.CGImage)

        default:
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.width,self.size.height), self.CGImage)
        }

        // And now we just create a new UIImage from the drawing context
        if let cgImage = CGBitmapContextCreateImage(ctx) {
            return UIImage(CGImage: cgImage)
        } else {
            return self
        }
    }
}
1赞 Meet Doshi 6/21/2016 #11

如果我明白了,你想做的是无视UIImage的方向?如果是这样,那么你可以这样做:-

//image is your original image
image = [UIImage imageWithCGImage:[image CGImage]
                             scale:[image scale]
                       orientation: UIImageOrientationUp];

或在 Swift 中:-

image = UIImage(CGImage: image.CGImage!, scale: image.scale, orientation:.Up)

它解决了我的裁剪问题..希望,这就是你要找的..

0赞 Faisal 9/27/2016 #12

Swift 3 版本基于从 @MetalHeart2003 那里拿走它的@jake1981

extension UIImage {

    func fixOrientation() -> UIImage {

        // No-op if the orientation is already correct
        if ( self.imageOrientation == UIImageOrientation.up ) {
            return self;
        }

        // 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.

        var transform: CGAffineTransform = CGAffineTransform.identity

        if ( self.imageOrientation == UIImageOrientation.down || self.imageOrientation == UIImageOrientation.downMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: self.size.height)
            transform = transform.rotated(by: CGFloat(M_PI))
        }

        if ( self.imageOrientation == UIImageOrientation.left || self.imageOrientation == UIImageOrientation.leftMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: 0)
            transform = transform.rotated(by: CGFloat(M_PI_2))
        }

        if ( self.imageOrientation == UIImageOrientation.right || self.imageOrientation == UIImageOrientation.rightMirrored ) {
            transform = transform.translatedBy(x: 0, y: self.size.height);
            transform = transform.rotated(by: CGFloat(-M_PI_2));
        }

        if ( self.imageOrientation == UIImageOrientation.upMirrored || self.imageOrientation == UIImageOrientation.downMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: 0)
            transform = transform.scaledBy(x: -1, y: 1)
        }

        if ( self.imageOrientation == UIImageOrientation.leftMirrored || self.imageOrientation == UIImageOrientation.rightMirrored ) {
            transform = transform.translatedBy(x: self.size.height, y: 0);
            transform = transform.scaledBy(x: -1, y: 1);
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        let ctx: CGContext = CGContext(data: nil, width: Int(self.size.width), height: Int(self.size.height),
                                       bitsPerComponent: self.cgImage!.bitsPerComponent, bytesPerRow: 0,
                                       space: self.cgImage!.colorSpace!,
                                       bitmapInfo: self.cgImage!.bitmapInfo.rawValue)!
        ctx.concatenate(transform)

        if ( self.imageOrientation == UIImageOrientation.left ||
            self.imageOrientation == UIImageOrientation.leftMirrored ||
            self.imageOrientation == UIImageOrientation.right ||
            self.imageOrientation == UIImageOrientation.rightMirrored ) {

            ctx.draw(self.cgImage!, in: CGRect(x: 0, y: 0, width: self.size.height, height: self.size.width))
        } else {
            ctx.draw(self.cgImage!, in: CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height))
        }

        // And now we just create a new UIImage from the drawing context and return it
        return UIImage(cgImage: ctx.makeImage()!)

    }
}
4赞 Yaroslav 3/29/2017 #13

根据 的答案更新 Swift 3.1,并清理代码。Sourabh Sharma

extension UIImage {
    func fixedOrientation() -> UIImage {
        if imageOrientation == .up { return self }

        var transform:CGAffineTransform = .identity
        switch imageOrientation {
        case .down, .downMirrored:
            transform = transform.translatedBy(x: size.width, y: size.height).rotated(by: .pi)
        case .left, .leftMirrored:
            transform = transform.translatedBy(x: size.width, y: 0).rotated(by: .pi/2)
        case .right, .rightMirrored:
            transform = transform.translatedBy(x: 0, y: size.height).rotated(by: -.pi/2)
        default: break
        }

        switch imageOrientation {
        case .upMirrored, .downMirrored:
            transform = transform.translatedBy(x: size.width, y: 0).scaledBy(x: -1, y: 1)
        case .leftMirrored, .rightMirrored:
            transform = transform.translatedBy(x: size.height, y: 0).scaledBy(x: -1, y: 1)
        default: break
        }

        let ctx = CGContext(data: nil, width: Int(size.width), height: Int(size.height),
                                       bitsPerComponent: cgImage!.bitsPerComponent, bytesPerRow: 0,
                                       space: cgImage!.colorSpace!, bitmapInfo: cgImage!.bitmapInfo.rawValue)!
        ctx.concatenate(transform)

        switch imageOrientation {
        case .left, .leftMirrored, .right, .rightMirrored:
            ctx.draw(cgImage!, in: CGRect(x: 0, y: 0, width: size.height,height: size.width))
        default:
            ctx.draw(cgImage!, in: CGRect(x: 0, y: 0, width: size.width,height: size.height))
        }
        return UIImage(cgImage: ctx.makeImage()!)
    }
}

选取器委托方法示例:

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
    guard let originalImage = info[UIImagePickerControllerOriginalImage] as? UIImage else { return }
    let fixedImage = originalImage.fixedOrientation()
    // do your work
}
3赞 Teena nath Paul 11/9/2017 #14

我从相机拍摄或保存在相机胶卷中的图像时遇到了这个问题,这些图像是从相机拍摄的。从Safari浏览器下载到照片库中的图像在上传时不会旋转。

我能够通过在上传前将图像数据制作为 JPEG 来解决这个问题。

let image = info[UIImagePickerControllerOriginalImage] as! UIImage        
let data = UIImageJPEGRepresentation(image, 1.0)

我们现在可以使用数据进行上传,并且上传后图像不会旋转。

希望这会起作用。

评论

0赞 user3344977 4/16/2020
奇怪的是,png 数据保持旋转状态,但在使用 jpeg 数据时旋转是固定的。
33赞 wzso 4/19/2018 #15

Swift 4.x/5.0版本的解决方案:@an0

extension UIImage {
    func upOrientationImage() -> UIImage? {
        switch imageOrientation {
        case .up:
            return self
        default:
            UIGraphicsBeginImageContextWithOptions(size, false, scale)
            draw(in: CGRect(origin: .zero, size: size))
            let result = UIGraphicsGetImageFromCurrentImageContext()
            UIGraphicsEndImageContext()
            return result
        }
    }
}

评论

1赞 Vinayak Bhor 6/1/2019
谢谢。它完美地工作。最被低估的答案。
0赞 Caterina Dmitrieva 2/12/2022
谢谢!在里面调用这个函数,它会修复图像方向imagePickerController
0赞 Oleksii Malyarenko 12/14/2018 #16
@an0, thanks for the answer!
The only thing is autoreleasepool: 

func fixOrientation(img: UIImage) -> UIImage? {

    let result: UIImage?
    if img.imageOrientation == .up {
        result = img
    } else {

        result = autoreleasepool { () -> UIImage? in
            UIGraphicsBeginImageContextWithOptions(img.size, false, img.scale)
            let rect = CGRect(x: 0, y: 0, width: img.size.width, height: img.size.height)
            img.draw(in: rect)

            let normalizedImage = UIGraphicsGetImageFromCurrentImageContext()
            UIGraphicsEndImageContext()

            return normalizedImage
        }
    }

    return result
}
0赞 Prashanth Thota 1/7/2019 #17

这是用于自动修复图像方向的 Swift-4.2 代码 返回 UIImage

func AutofixImageOrientation(_ image: UIImage)->UIImage {

    UIGraphicsBeginImageContext(image.size)

    image.draw(at: .zero)

    let newImage = UIGraphicsGetImageFromCurrentImageContext()

    UIGraphicsEndImageContext()

    return newImage ?? image
}
0赞 Gustavo Baiocchi Costa 1/22/2019 #18

我将其转置到 Xamarin 中:

private static UIImage FixImageOrientation(UIImage image)
    {
        if (image.Orientation == UIImageOrientation.Up)
        {
            return image;
        }

        var transform = CGAffineTransform.MakeIdentity();

        float pi = (float)Math.PI;

        switch (image.Orientation)
        {
            case UIImageOrientation.Down:
            case UIImageOrientation.DownMirrored:
                transform = CGAffineTransform.Translate(transform, image.Size.Width, image.Size.Height);
                transform = CGAffineTransform.Rotate(transform, pi);
                break;

            case UIImageOrientation.Left:
            case UIImageOrientation.LeftMirrored:
                transform = CGAffineTransform.Translate(transform, image.Size.Width, 0);
                transform = CGAffineTransform.Rotate(transform, pi / 2);
                break;

            case UIImageOrientation.Right:
            case UIImageOrientation.RightMirrored:
                transform = CGAffineTransform.Translate(transform, 0, image.Size.Height);
                transform = CGAffineTransform.Rotate(transform, -(pi / 2));
                break;
        }

        switch (image.Orientation)
        {
            case UIImageOrientation.UpMirrored:
            case UIImageOrientation.DownMirrored:
                transform = CGAffineTransform.Translate(transform, image.Size.Width, 0);
                transform = CGAffineTransform.Scale(transform, -1, 1);
                break;

            case UIImageOrientation.LeftMirrored:
            case UIImageOrientation.RightMirrored:
                transform = CGAffineTransform.Translate(transform, image.Size.Height, 0);
                transform = CGAffineTransform.Scale(transform, -1, 1);
                break;
        }

        var ctx = new CGBitmapContext(null, (nint)image.Size.Width, (nint)image.Size.Height, image.CGImage.BitsPerComponent,
            image.CGImage.BytesPerRow, image.CGImage.ColorSpace, image.CGImage.BitmapInfo);

        ctx.ConcatCTM(transform);

        switch (image.Orientation)
        {
            case UIImageOrientation.Left:
            case UIImageOrientation.LeftMirrored:
            case UIImageOrientation.Right:
            case UIImageOrientation.RightMirrored:
                ctx.DrawImage(new CGRect(0, 0, image.Size.Height, image.Size.Width), image.CGImage);
                break;

            default:
                ctx.DrawImage(new CGRect(0, 0, image.Size.Width, image.Size.Height), image.CGImage);
                break;
        }

        var cgimg = ctx.ToImage();
        var img = new UIImage(cgimg);

        ctx.Dispose();
        ctx = null;
        cgimg.Dispose();
        cgimg = null;

        return img;
    }
7赞 sushmit yadav 6/7/2019 #19

我通过在下面编写几行代码来实现这一点

extension UIImage {

    public func correctlyOrientedImage() -> UIImage {
        guard imageOrientation != .up else { return self }

        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        draw(in: CGRect(origin: .zero, size: size))
        let normalizedImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()

        return normalizedImage
    }
}
5赞 0xced 10/16/2019 #20

这是一个不会更改原始图像色彩空间的解决方案。如果要对灰度图像的方向进行归一化,则所有基于该解决方案的解决方案都不走运,因为它会在RGB色彩空间中创建上下文。相反,您必须创建一个具有与原始图像相同属性的上下文并绘制:UIGraphicsBeginImageContextWithOptions

extension UIImage {
    static let rotatedOrentations: [UIImage.Orientation] = [.left, .leftMirrored, .right, .rightMirrored]

    func normalizedImage() -> UIImage {
        if imageOrientation == .up {
            return self
        }

        let image = self.cgImage!
        let swapOrientation = UIImage.rotatedOrentations.contains(imageOrientation)
        let width = swapOrientation ? image.height : image.width
        let height = swapOrientation ? image.width : image.height
        let context = CGContext(data: nil, width: width, height: height, bitsPerComponent: image.bitsPerComponent, bytesPerRow: image.bytesPerRow, space: image.colorSpace!, bitmapInfo: image.bitmapInfo.rawValue)!
        let flipVertical = CGAffineTransform(a: 1, b: 0, c: 0, d: -1, tx: 0, ty: CGFloat(height));
        context.concatenate(flipVertical)
        UIGraphicsPushContext(context)
        self.draw(at: .zero)
        UIGraphicsPopContext()

        return UIImage(cgImage: context.makeImage()!)
    }
}