Do not use uiimagepickercontrolleroriginalimage to obtain the source Image

Generally, you can use imagepickercontroller to obtain the DIC.

Uiimage * image = [DIC objectforkey: @ "uiimagepickercontrolleroriginalimage"];

To obtain the source image, but I used this method to obtain the image not the source image, but the size after compression. Then I found a new method to obtain the source image and paste the Code directly.

       ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];            [library assetForURL:[dic objectForKey:UIImagePickerControllerReferenceURL]                     resultBlock:^(ALAsset *asset)             {                 ALAssetRepresentation *representation = [asset defaultRepresentation];                 CGImageRef imgRef = [representation fullResolutionImage];                 UIImage *image = [UIImage imageWithCGImage:imgRef                                                    scale:representation.scale                                              orientation:(UIImageOrientation)representation.orientation];                 NSData * data = UIImageJPEGRepresentation(image, 0.5);                             }failureBlock:^(NSError *error){                 NSLog(@"couldn‘t get asset: %@", error);             }             ];