Render to low res black and white

[arsu-leo]

I'm trying to render some text as completely black and white to png in low resolution (~200 dpi, actually pointing to 8 px per mm)

Rendering the svg gives text with grayscale bordering:
Sample

But I'm looking looking for the following result:
Desired

I have tried several combiantions of graphics options (including set none) but I have not been able to achieve the desired result.

Simplified sample code:

public Bitmap Draw()
{
             byte[] byteArray = Encoding.UTF8.GetBytes(SVG_CODE);
            using MemoryStream stream = new MemoryStream(byteArray);
            SvgDocument Doc =  SvgDocument.Open<SvgDocument>(stream);

            int w = 320;
            int h = 1280; 
            Bitmap bmp = new Bitmap(w, h, PixelFormat.Format32bppArgb);
            float density = (float)203.2;
            bmp.SetResolution(density, density);
            using Graphics g = Graphics.FromImage(bmp);
            g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAlias;
            //Set some of the graphics properties so that the text renders nicely
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
            //Compositing Mode can't be set since string needs source over to be valid
            g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
            g.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
            //And an additional step to make sure text is proper anti-aliased and takes advantage
            //of clear type as necessary
            g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit;
            Doc.Draw(g);
            return bmp;
}
const string SVG_CODE = @"<svg width=""320"" height=""1280"" position=""relative"" xml=""http://www.w3.org/XML/1998/namespace""
  xmlns:xlink=""http://www.w3.org/1999/xlink""
  xmlns:xml=""http://www.w3.org/XML/1998/namespace"" version=""1.1""
  xmlns=""http://www.w3.org/2000/svg"">
  <defs />
  <g class=""svg-in-label-background"">
    <rect x=""0"" y=""0"" width=""100%"" height=""100%"" fill-opacity=""0"" />
  </g>
  <g class=""svg-in-label-elements-container"">
    <g transform=""matrix(1, 0, 0, 1, 0, 0)"" text-anchor=""start"" font-family=""'Arial Narrow'"" font-size=""16px"" font-style=""normal"" text-decoration=""none"" font-weight=""700"" data-id=""-317631"" wrap-mode=""WRAP_INCREASE_HORIZONTAL_SIZE"" gl22-rotation-degrees=""0"" class=""svg-model-element svg-model-element-text"" style=""fill:black;"">
      <text x=""16"" y=""88"">
        <tspan x=""16"" dy=""1.2em"">Produkt      CLEMENTINEN</tspan>
        <tspan x=""16"" dy=""1.2em"" visibility=""hidden"">HIDDEN</tspan>
        <tspan x=""16"" dy=""1.2em"">Sorte:</tspan>
      </text>
    </g>
    <g transform=""matrix(1, 0, 0, 1, 0, 0)"" text-anchor=""start"" font-family=""'Arial Narrow'"" font-size=""42px"" font-style=""normal"" text-decoration=""none"" font-weight=""700"" data-id=""-851205"" wrap-mode=""WRAP_INCREASE_HORIZONTAL_SIZE"" gl22-rotation-degrees=""0"" class=""svg-model-element svg-model-element-text"" style=""fill:black;"">
      <text x=""64"" y=""104"">
        <tspan x=""64"" dy=""1.2em"">CLEMENRUBI</tspan>
      </text>
    </g>
  </g>
</svg>";

I'm trying to replicate some old Java code but instead of rendering each piece as that old code used to do, I'm using an Svg:

//Java code
for (Part part : figures){
  IFigure figure = part.getFigure();
  GC gc = new GC(image);
  gc.setAntialias(SWT.OFF);
  gc.setTextAntialias(SWT.OFF);

  // create the graphics to draw the figure.
  final Graphics graphics = new SWTGraphics(gc);
  graphics.translate(bounds.getLocation().negate());

  // Paint the figure.
  figure.paint(graphics);
  graphics.dispose();
  gc.dispose();
  part.dispose();
}

There, setting the antialias is trivial and works like a charm as the Desired image shows.

Is there any way to achieve the desired result?

[H1Gdev]

Why not try disabling anti-aging with SVG shape-rendering ?

[H1Gdev]

I'm not sure what effect you expect, but I paste the code I tested.

            var d = new Bitmap(1446, 532);
            {
                using (var s = new Bitmap(320, 1280))
                {
                    using (var g = SvgRenderer.FromImage(s))
                    {
                        ((IGraphicsProvider)g).GetGraphics().TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit;
                        ((IGraphicsProvider)g).GetGraphics().CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighSpeed;
                        svgDoc.Draw(g);
                    }
                    using (var g = Graphics.FromImage(d))
                    {
                        g.DrawImage(s, -20f, -700f, s.Width * 8f, s.Height * 8f);
                    }
                }
            }

[arsu-leo]

Hi,
This process gave me a really good result, really accurate given what I was looking for.
Unfortunately, the software I'm transitioning form, gave a slightly bolder text on all cases and the output on the special printer for it was not acceptable in comparison, 1 line of pixels is not that visible.

At end, I had to keep the antialiasing and then process grey pixels through a threshold filter so I would get 2 pixels wide on some places:
Rendering modification on graphics element:

                //Code section to render SVG to bitmap
                g.CompositingQuality = CompositingQuality.HighQuality;
                g.SmoothingMode = SmoothingMode.AntiAlias;
                g.TextRenderingHint = TextRenderingHint.ClearTypeGridFit;

//Code section to evaluate a color must be taken either as black or as white:
public static bool ColorIsWhite(int a, int r, int g, int b, double threshold)
        {
            //Fully transparent, color is white
            if (a == 0)
            {
                return true;
            }

            //Note to myself: [0,0,0] is black
            double transparenceyPercentage = a / (double)byte.MaxValue;
            double blackPercentage = byte.MaxValue - ((r + g + b) / 3.0);
            double finalBlackPercentage = transparenceyPercentage * blackPercentage;
            double thr = byte.MaxValue * threshold;
            return finalBlackPercentage <= thr;
}

For the threshold, range [0.25-0.35] gave me desired results, ended up using 0.25. Still is a configurable value.

I may have somewhere the choice to use direct rendering (Your graphics suggestion) or antialiased + threshold system.