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等)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。任何的想法?
PS:我已经尝试this way,但它在iOS 10.3.1
上无效