How to generate a monochrome bitmap with a bit depth of 1 in BMP format?

[jingxin2015]

Due to printing requirements, I need to use it NET6 generates a monochrome bitmap in BMP format with a bit depth of 1, a white background, and black text. May I ask Magick Can NET be implemented? My program needs to be deployed on the Ubuntu system, thank you!

[dlemstra]

This should already be supported? What have you tried so far?

[jingxin2015]

@dlemstra

         var fontPath = webHostEnvironment.WebRootPath + "/fonts/SimSun.ttf".Replace('/', Path.DirectorySeparatorChar);

        using var image = new MagickImage(MagickColors.White, 500, 700);
        image.Format = MagickFormat.Bmp;
        image.Depth = 1;

        var drawables = new Drawables();

        drawables.Font(fontPath, FontWeight.Bold, FontStretch.Normal);
        drawables.TextEncoding(Encoding.UTF8);
        drawables.FontPointSize(12);
        drawables.FillColor(MagickColors.Black);
        drawables.Text(0, 0, "单色位图");

        drawables.Draw(image);

        image.Write(webHostEnvironment.WebRootPath + "/images/test1bit.bmp".Replace('/', Path.DirectorySeparatorChar));

I tried the above code and the generated image is still 32-bit deep. If the format is set to MagickFormat Bmp3 generates a depth of 24 bits.

[dlemstra]

You should set image.ColorType to ColorType.Bilevel after you have called .Draw(image). This makes sure that the image becomes monochrome.

[jingxin2015]

You're right, thank you very much!