使用元数据将照片保存到具有特定文件名的相机胶卷中

我正在尝试使用以下代码使用exif元数据保存图像：

+(void)saveImageWithMetaToCameraRoll:(UIImage*)image location:(CLLocation*)location album:(PHAssetCollection *)album exif:(NSDictionary *)metadata isOriginal:(BOOL)isOriginal isFavorite:(BOOL)isFavorite completionBlock:(PHAssetBoolBlock)completionBlock { NSMutableDictionary *meta = [metadata mutableCopy]; NSData *imageData = UIImageJPEGRepresentation(image, 1.0f); CGImageSourceRef source = CGImageSourceCreateWithData((__bridge CFDataRef) imageData, NULL); if (!isOriginal) { [meta resetOrientation]; } NSString *timestamp = [NSString stringWithFormat:@"%.0f", [[NSDate date] timeIntervalSince1970] * 1000]; NSString *fileName = [NSString stringWithFormat:@"IMG_%@_%@.jpeg", timestamp, isOriginal ? @"orig" : @"d"]; [meta setTitle:fileName]; NSURL *tmpURL = [NSURL fileURLWithPath:[NSTemporaryDirectory() stringByAppendingPathComponent:fileName]]; CGImageDestinationRef destination = CGImageDestinationCreateWithURL((__bridge CFURLRef) tmpURL, kUTTypeJPEG, 1, NULL); CGImageDestinationAddImageFromSource(destination, source, 0, (__bridge CFDictionaryRef) meta); CGImageDestinationFinalize(destination); CFRelease(source); CFRelease(destination); [[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{ PHAssetChangeRequest *newAssetRequest = [PHAssetChangeRequest creationRequestForAssetFromImageAtFileURL:tmpURL]; PHObjectPlaceholder *placeholderAsset = newAssetRequest.placeholderForCreatedAsset; if (album) { PHAssetCollectionChangeRequest *changeRequest = [PHAssetCollectionChangeRequest changeRequestForAssetCollection:album]; [changeRequest addAssets:@[placeholderAsset]]; } } completionHandler:^(BOOL success, NSError *error) { //Clean up the file: [[NSFileManager defaultManager] removeItemAtURL:tmpURL error:nil]; if (error) { NSLog(@"%@", error); } completionBlock(success); }]; } 

注意到某些应用程序（Snapseed，Photoshop和其他应用程序）在将图像导出到相机胶卷时能够设置自定义文件名。 我无法弄清楚他们究竟是如何做到这一点的。 任何想法？

PS：我已经尝试过这种方式 ，它在iOS 10.3.1上无效