HOWTO: Drawing graphics/text on CMYK images

//For saving the original startup folder of the this file
protected string startupFolder;

private void Page_Load(object sender, System.EventArgs e)
{
	//Save the original startup folder of the this application for loading files
	startupFolder = Server.MapPath("./");			

	Aurigma.GraphicsMill.Bitmap bitmap = new Aurigma.GraphicsMill.Bitmap(Aurigma.GraphicsMill.RgbColor.White, 1038, 688,
		 Aurigma.GraphicsMill.PixelFormat.Format40bppAcmyk);
	
	//Create the color to draw with
	Aurigma.GraphicsMill.CmykColor rectColor = Aurigma.GraphicsMill.CmykColor.FromCmyk(214, 99, 255, 94);
	
	//Draw a CMYK rectangle
	//drawRectangleCMYK(bitmap,x,y,width,height,CMYKcolor,opacity,rotation);
	bitmap = drawRectangleCMYK(bitmap,100,100,50,50,rectColor,128,45);
	bitmap = drawRectangleCMYK(bitmap,125,125,50,50,rectColor,128,45);
	bitmap = drawRectangleCMYK(bitmap,200,200,50,50,rectColor,255,0);
	bitmap = drawRectangleCMYK(bitmap,300,300,50,50,rectColor,255,180);
	
	//save the output
	bitmap.Save(startupFolder+[color=CC0000]"cmyk32.jpg", new JpegEncoderOptions(100, true));
}
				
private Aurigma.GraphicsMill.Bitmap drawRectangleCMYK(Aurigma.GraphicsMill.Bitmap bitmap, float fX,float fY, float fWidth, 
						float fHeight, Aurigma.GraphicsMill.CmykColor CMYKcolor, int iOpacity, float fRotation) {

	//Create rotation matrix
	System.Drawing.Drawing2D.Matrix matrix = new System.Drawing.Drawing2D.Matrix();
	matrix.RotateAt(fRotation, new System.Drawing.PointF(fX+fWidth/2,fY+fHeight/2));

	//Get the color channels
	Aurigma.GraphicsMill.ColorChannel[] channels = {Aurigma.GraphicsMill.ColorChannel.Cyan,
											Aurigma.GraphicsMill.ColorChannel.Magenta,
											Aurigma.GraphicsMill.ColorChannel.Yellow,
											Aurigma.GraphicsMill.ColorChannel.Black};

	//Get the colors
	int[] colors = {CMYKcolor.C,CMYKcolor.M,CMYKcolor.Y,CMYKcolor.K};

	//For storing the working color channel
	Aurigma.GraphicsMill.Bitmap colorChannel;

	//Begin processing each color channel
	for(int i = 0;i<4;i++) {
		
		colorChannel = bitmap.Channels[channels[ i ]];
		
		//Convert it to RGB, so that GetGdiplusGraphics can work with it
		//if you only need GetGdiGraphics, then there is no need to change colorSpaces
		colorChannel.ColorManagement.ConvertToContinuous(Aurigma.GraphicsMill.ColorSpace.Rgb,false, false);
		
		//Can't use GetGdiGraphics, we want Anti-alias
		System.Drawing.Graphics graphics = colorChannel.GetGdiplusGraphics();

		//Turn on AntiAliasing on draw
		graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;

		//Create a solid brush colored with the RGB color and opacity specified	
		System.Drawing.SolidBrush brush = new 
				System.Drawing.SolidBrush(System.Drawing.Color.FromArgb(iOpacity, colors[ i ], colors[ i ], colors[ i ]));
		
		//Apply rotation
		graphics.Transform = matrix;
						
		//Draw the filled rectangle
		graphics.FillRectangle(brush, fX, fY, fWidth, fHeight);
		
		//Convert RGB back to grayscale
		colorChannel.ColorManagement.ConvertToContinuous(Aurigma.GraphicsMill.ColorSpace.GrayScale,false, false);
		
		//Put the channel back in the image
		bitmap.Channels[channels[ i ]] = colorChannel;
	}						
	
	return bitmap;
}