public static void ExportToJpeg() {
    prepare(true);
    SaveFileDialog saveDialog = new SaveFileDialog
    {
        Filter = "JPEG Files (*.jpeg)|*.jpeg",
        DefaultExt = ".jpeg",
    };
    if ((bool)saveDialog.ShowDialog()) {
        using (Stream fileStream = saveDialog.OpenFile()) {
            WriteableBitmap bitmap = new WriteableBitmap(containerPanel, null);