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

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;
}

然后在某个时候,我使用ASI类将它发送到我的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];

存在的问题: 当我拿着iPhone拍照时,照片会被上传到服务器,就像你期望的那样。手持竖屏拍照时,上传的照片是旋转90度后观看的。

我的应用程序被设置为只在纵向模式(倒置和常规)下工作。

我怎样才能使图像始终显示正确的方向后上传?

在UIImageView中显示的图像是正确的(直接在拍照后),但在服务器上查看则不然。


当前回答

迅捷;)

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
}

其他回答

Swift 4.x/5.0版本的@an0解决方案:

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
        }
    }
}

Swift 3版本基于@jake1981,他从@MetalHeart2003中获得了它

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()!)

    }
}

如果我没理解错的话,你想做的是忽略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];

或者用Swift:-

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

它解决了我的裁剪问题。霍普,这就是你要找的…

我把这个换成了Xamarin:

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;
    }

下面是Swift-4.2自动修正图像方向的代码 返回界面图像

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

    UIGraphicsBeginImageContext(image.size)

    image.draw(at: .zero)

    let newImage = UIGraphicsGetImageFromCurrentImageContext()

    UIGraphicsEndImageContext()

    return newImage ?? image
}