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 {      }}