//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;
}