How to generate thumbnails in c#

 private void SaveThumbnail(Bitmap originBitmap, int width, int height, string directory, string filename, string extension)
{
    var physicalPath = directory + filename + extension;

    using (var newImage = new Bitmap(width, height))
    {
        using (var graphic = GetGraphic(originBitmap, newImage))
        {
            (originBitmap, 0, 0, width, height);
            using (var encoderParameters = new EncoderParameters(1))
            {
                [0] = new EncoderParameter(, 100L);
                (physicalPath,
                            ()
                                .Where(x => (()))
                                .FirstOrDefault(),
                            encoderParameters);
            }
        }
    }           
}

private Graphics GetGraphic(Image originImage, Bitmap newImage)
{
    (, );
    var graphic = (newImage);
    = .;
    = .;
    = .;
    = .;
    return graphic;
}