public Task<Tuple<bool, AVIMVideoMessage>> SendVideoMessageAsync(AVIMVideoMessage avVideoMessage)
 {
     return InternalExtensions.OnSuccess<Tuple<bool, AVIMFileMessageBase>, Tuple<bool, AVIMVideoMessage>>(this.SendFileMessageAsync((AVIMFileMessageBase)avVideoMessage), (Func<Task<Tuple<bool, AVIMFileMessageBase>>, Tuple<bool, AVIMVideoMessage>>)(x => new Tuple<bool, AVIMVideoMessage>(x.Result.Item1, avVideoMessage)));
 }
        private async void SendVideo()
        {
            StorageFolder local = Windows.Storage.ApplicationData.Current.LocalFolder;

            var VideoFile = await local.OpenStreamForReadAsync(recordVideoFileName);

            AVIMVideoMessage videoMessage = new AVIMVideoMessage(recordVideoFileName, VideoFile);

            await conversation.SendVideoMessageAsync(videoMessage);
        }