func thumbnailOfVideo(path : String)-> UIImage { do {  let asset = AVURLAsset(url: URL(fileURLWithPath: path), options: nil)  let imgGenerator = AVAssetImageGenerator(asset: asset)  imgGenerator.appliesPreferredTrackTransform = true  let cgImage = try imgGenerator.copyCGImage(at: CMTimeMakeWithSeconds(1, 24), actualTime: nil)  let uiImage = UIImage(cgImage: cgImage)  return uiImage } catch {  return UIImage(named: "default_figure")! }}

#import <AssetsLibrary/AssetsLibrary.h>- (void)saveVideoIntoAlbum { NSString *fileDirectory =  NSFileManager *fileManager = [NSFileManager defaultManager]; NSArray *fileArray = [fileManager contentsOfDirectoryAtPath:fileDirectory error:nil]; NSString *filePath = [fileDirectory stringByAppendingPathComponent:[fileArray lastObject]]; NSURL *fileUrl = [NSURL fileURLWithPath:filePath];  NSLog(@"fileUrl = %@", fileUrl); ALAssetsLibrary *assetslibrary = [[ALAssetsLibrary alloc] init];  if ([assetslibrary videoAtPathIsCompatibleWithSavedPhotosAlbum:fileUrl]) {  [assetslibrary writeVideoAtPathToSavedPhotosAlbum:fileUrl completionBlock:^(NSURL *assetURL, NSError *error) {   NSLog(@"%@-----%@", assetURL, error);  }]; } else {   }}