private void btnSaveStream_Click(object sender, RoutedEventArgs e) { SaveFileDialog saveFileDialog = new SaveFileDialog(); saveFileDialog.Filter = "Image files (*.png;*.jpg;*.jpeg)|*.png;*.jpg;*.jpeg"; saveFileDialog.InitialDirectory = System.AppDomain.CurrentDomain.BaseDirectory; if (saveFileDialog.ShowDialog() == true) { File.WriteAllBytes(saveFileDialog.FileName, BlockCipher.imageToByteArray(_encryptedBitmap)); } }