在服务器上传图像，接收旋转后的图像

Question

在我的应用程序中，我想将图像上传到服务器，并检索上传图像的URL以将其显示在应用程序中。我发送图像的NSData。这是我的代码：

AsynchronousImageView *imgVw_User = (AsynchronousImageView*)[self.view viewWithTag:K_TagImageViewUser]; 
UIImage *UserImgForBioData = imgVw_User.image; 
UserImgForBioData = [UIImage imageWithCGImage:UserImgForBioData.CGImage scale:1.0f orientation:UserImgForBioData.imageOrientation]; 
NSData *imageData = [NSData dataWithData:UIImageJPEGRepresentation(UserImgForBioData,0.5)]; 

Base64Transcoder *temp_transcoder=[[Base64Transcoder alloc]init]; 
NSString * temp_base64EncodedImage= @""; 
if (imageData!=nil) 
    { 
     temp_base64EncodedImage = [NSString stringWithFormat:@"%@",[temp_transcoder base64EncodedStringfromData:imageData]]; 
     temp_base64EncodedImage = [[temp_base64EncodedImage stringByReplacingOccurrencesOfString:@"\n" 
              withString:@""] 
             mutableCopy]; 
     } 

有时当我显示图像时，通过获取图像的url，图像被旋转。难道我做错了什么？

Answer 1

如果[R从摄像机捕捉图像，然后上传图像通过该生成图像缩略图在原来的方向前：在此之后

- (UIImage *)generatePhotoThumbnail:(UIImage *)image 
{ 
    //int kMaxResolution = 320; 

    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"]; 
      break; 
    } 

    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(); 

    return imageCopy; 

} 

u得到正确的图像，然后上传图片。我希望这会解决你的问题。

第1步：从相机捕捉图像。

第二步：然后上传所得到的图像：通过以下方法

第三步生成photoThumbnail。

使用从照片库中的图像时，你会得到正确的图像

Answer 2

这为我工作。

ALAssetRepresentation *rep = [_asset defaultRepresentation]; 
CGImageRef iref = [rep fullResolutionImage]; 
UIImage* img = [UIImage imageWithCGImage:iref scale:1.f orientation:UIImageOrientationUp] 

注意：_asset是ALAsset的一个实例。