Generating document preview - advanced Leave feedback

public static void GetPreview()
{
    // The path to the documents directory.
    string filePath = Constants.SAMPLE_WORD_SIGNED;
    using (Signature signature = new Signature(filePath))
    {
        // create preview options object
        PreviewOptions previewOption = new PreviewOptions(CreatePageStream, ReleasePageStream)
        {
            PreviewFormat = PreviewOptions.PreviewFormats.JPEG,
            // set property to hide all known signatures
            HideSignatures = true
        };
        // generate preview
        signature.GeneratePreview(previewOption);
    }
}

private static Stream CreatePageStream(PreviewPageData pageData)
{
    string imageFilePath = Path.Combine("GeneratePreviewFolder", "image-" + pageData.PageNumber.ToString() + ".jpg");
    var folder = Path.GetDirectoryName(imageFilePath);
    if(!Directory.Exists(folder))
    {
       Directory.CreateDirectory(folder);
    }
    return new System.IO.FileStream(imageFilePath, FileMode.Create);
}

private static void ReleasePageStream(PreviewPageData pageData, Stream pageStream)
{
    pageStream.Dispose();
    string imageFilePath = Path.Combine("GeneratePreviewFolder", "image-" + pageData.PageNumber.ToString() + ".jpg");
    Console.WriteLine("Image file {0} is ready for preview", imageFilePath);
}