public class EnlargeQRCode
{
    public GcBitmap GenerateImage(Size pixelSize, float dpi, bool opaque, string[] sampleParams = null)
    {
        // Create and clear the target bitmap.
        var targetBmp = new GcBitmap(pixelSize.Width, pixelSize.Height, opaque, dpi, dpi);
        targetBmp.Clear(Color.Transparent);

        const int fontSize = 16;
        var xpad = (int)(dpi * .5f);
        var ypad = (int)(dpi * .7f);

        // Initialize Font.
        TextFormat tf = new TextFormat
        {
            Font = GCTEXT.Font.FromFile(Path.Combine("Resources", "Fonts", "times.ttf")),
            FontSize = fontSize,
        };

        // Load the image.
        using var origBmp = new GcBitmap();
        using (var stm = File.OpenRead(Path.Combine("Resources", "ImagesBis", "QRCode-57x57.png")))
            origBmp.Load(stm);

        // Match the opaqueness of the original bitmap and the target.
        origBmp.Opaque = targetBmp.Opaque;

        var ip = new Point(xpad, ypad);

        // Draw the original image at its original size.
        targetBmp.BitBlt(origBmp, ip.X, ip.Y);
        using (var g = targetBmp.CreateGraphics(null))
            g.DrawString($"⟵ Original image ({origBmp.PixelWidth} by {origBmp.PixelHeight} pixels)", tf, new PointF(xpad * 2 + origBmp.Width, ip.Y));
        ip.Y += origBmp.PixelHeight + ypad;

        // Enlarge the original small image by a factor of 6.
        var f = 6;
        int twidth = origBmp.PixelWidth * f;
        int theight = origBmp.PixelHeight * f;

        // Enlarge and draw four copies of the image using the four different available interpolation modes.
        using (var bmp = origBmp.Resize(twidth, theight, InterpolationMode.NearestNeighbor))
            targetBmp.BitBlt(bmp, ip.X, ip.Y);
        drawCaption("InterpolationMode.NearestNeighbor", ip.X, ip.Y + theight);

        using (var bmp = origBmp.Resize(twidth, theight, InterpolationMode.Cubic))
            targetBmp.BitBlt(bmp, ip.X + twidth + xpad, ip.Y);
        drawCaption("InterpolationMode.Cubic", ip.X + twidth + xpad, ip.Y + theight);

        ip.Y += theight + ypad;

        using (var bmp = origBmp.Resize(twidth, theight, InterpolationMode.Linear))
            targetBmp.BitBlt(bmp, ip.X, ip.Y);
        drawCaption("InterpolationMode.Linear", ip.X, ip.Y + theight);

        using (var bmp = origBmp.Resize(twidth, theight, InterpolationMode.Downscale))
            targetBmp.BitBlt(bmp, ip.X + twidth + xpad, ip.Y);
        drawCaption("InterpolationMode.Downscale", ip.X + twidth + xpad, ip.Y + theight);
        
        void drawCaption(string caption, float x, float y)
        {
            using var g = targetBmp.CreateGraphics(null);
            g.DrawString(caption, tf, new PointF(x, y));
        }
        return targetBmp;
    }
}