New Post: Bitmap Image to 1Bpp image

using (MagickImage image = new MagickImage("logo:"))
{
    image.Threshold(50);
    image.Depth = 1;
    image.Write(@"C:\logo-1.png");
}

using (MagickImage image = new MagickImage("logo:"))
{
    image.ColorType = ColorType.Bilevel;
    image.Depth = 1;
    image.Write(@"C:\logo-2.png");
}

using (MagickImage image = new MagickImage("logo:"))
{
    QuantizeSettings settings = new QuantizeSettings();
    settings.ColorSpace = ColorSpace.GRAY;
    settings.Colors = 2;

    image.Quantize(settings);
    image.Depth = 1;
    image.Write(@"C:\logo-3.png");
}