使用Http Post成功上传到服务器后，图像变为水平

我使用图像选择器捕获图像，此时图像处于其实际位置。 但在服务器上传后它变得水平。 我不知道为什么会发生这种情况。

这是我的代码

NSString *urlString = @"Url"; NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease]; [request setURL:[NSURL URLWithString:urlString]]; [request setHTTPMethod:@"POST"]; NSMutableData *body = [NSMutableData data]; NSString *boundary = [NSString stringWithString:@"---------------------------14737809831466499882746641449"]; NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@", boundary]; [request addValue:contentType forHTTPHeaderField:@"Content-Type"]; // file NSData *imageData = UIImageJPEGRepresentation(image.image, 90); [body appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]]; // [body appendData:[[NSString stringWithString:@"Content-Disposition: attachment; name=\"user_photo\"; filename=\"photoes.jpg\"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"image\"; filename=\"%@.jpg\"\r\n",@"ImageNmae"] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[NSData dataWithData:imageData]]; [body appendData:[[NSString stringWithString:@"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"desc\"\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[[NSString stringWithString:ImageDesc.text] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[[NSString stringWithString:@"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]]; // close form [body appendData:[[NSString stringWithFormat:@"--%@--\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]]; // set request body [request setHTTPBody:body]; //return and test NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil]; NSString *returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding]; 

Answer 1

我发现这里的解决方案是代码。

 - (UIImage *)scaleAndRotateImage:(UIImage *)image { // here we rotate the image in its orignel int kMaxResolution = 640; // 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 = roundf(bounds.size.width / ratio); } else { bounds.size.height = kMaxResolution; bounds.size.width = roundf(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(); return imageCopy; } 

Answer 2

方向（在您的情况下旋转）位于图像的exif数据中。 您需要在iOS上预旋转图像或在服务器上后旋转它们。

在iOS上，您可以检查UIImage的imageOrientation属性。

您可以使用剪切的代码获取转换（您需要设置大小或更改代码部分。大小可能是原始大小）：

 - (CGAffineTransform)transformForOrientation:(CGSize)newSize { CGAffineTransform transform = CGAffineTransformIdentity; switch (self.imageOrientation) { case UIImageOrientationDown: // EXIF = 3 case UIImageOrientationDownMirrored: // EXIF = 4 transform = CGAffineTransformTranslate(transform, newSize.width, newSize.height); transform = CGAffineTransformRotate(transform, M_PI); break; case UIImageOrientationLeft: // EXIF = 6 case UIImageOrientationLeftMirrored: // EXIF = 5 transform = CGAffineTransformTranslate(transform, newSize.width, 0); transform = CGAffineTransformRotate(transform, M_PI_2); break; case UIImageOrientationRight: // EXIF = 8 case UIImageOrientationRightMirrored: // EXIF = 7 transform = CGAffineTransformTranslate(transform, 0, newSize.height); transform = CGAffineTransformRotate(transform, -M_PI_2); break; } switch (self.imageOrientation) { case UIImageOrientationUpMirrored: // EXIF = 2 case UIImageOrientationDownMirrored: // EXIF = 4 transform = CGAffineTransformTranslate(transform, newSize.width, 0); transform = CGAffineTransformScale(transform, -1, 1); break; case UIImageOrientationLeftMirrored: // EXIF = 5 case UIImageOrientationRightMirrored: // EXIF = 7 transform = CGAffineTransformTranslate(transform, newSize.height, 0); transform = CGAffineTransformScale(transform, -1, 1); break; } return transform; } 

当然你需要以某种方式将变换应用到你的UIImage。 但我想你会在stackoverflow的其他问题中找到它。 也许从这里开始。

Answer 3

它是媒体上传的一个很好的查询。

从设备捕获图像时，它会修复特定图像的方向。 假设您以横向模式捕获图像，当您使用imageView显示此图像时，它会以纵向模式显示，因为基本设备配置同时支持图像（横向和纵向），然后它可能会假装自己为肖像，而实际存储在横向中。 因此，当您在UI（imageView）中以纵向显示图像时，它将在服务器中保存。 最后1）图像水平写在设备上。 2）由于纵向模式激活应用程序，您已在UI上垂直显示它。 3）但是当它将被写入服务器时，它将采用其原始模式（水平）。

因此，根据最佳建议，您应该在应用程序中以正确模式显示媒体。

Answer 4

  NSData *imageData = UIImageJPEGRepresentation(image.image, 90); 

90°旋转角度不是？

阅读文档后编辑

  NSData *imageData = UIImageJPEGRepresentation(image.image, 90); 

看起来90应该是0.9。 可能不是问题。