title: How to increase the color tone of a picture in C#?
body: <p>I have got the picture that has got a text in it. I have already converted that picture into grayscale by using the ColorMatrix. </p>
  
  <pre><code>public Bitmap MakeGrayscale(Bitmap original)
  {
      //create a blank bitmap the same size as original
      Bitmap newBitmap = new Bitmap(original.Width, original.Height);
  
      //get a graphics object from the new image
      Graphics g = Graphics.FromImage(newBitmap);
  
      //create the grayscale ColorMatrix
      ColorMatrix colorMatrix = new ColorMatrix(
         new float[][] 
           {
       new float[] {.3f, .3f, .3f, 0, 0}, // 30% red.
       new float[] {.59f, .59f, .59f, 0, 0}, // 59% green.
       new float[] {.11f, .11f, .11f, 0, 0}, // 11% blue.
       new float[] {0, 0, 0, 1, 0},
       new float[] {0, 0, 0, 0, 1}
            });
  
      //create some image attributes
      ImageAttributes attributes = new ImageAttributes();
  
  
      //set the color matrix attribute
      attributes.SetColorMatrix(colorMatrix);
  
      //draw the original image on the new image
      //using the grayscale color matrix
      g.DrawImage(original, new Rectangle(0, 0, original.Width, original.Height),
         0, 0, original.Width, original.Height, GraphicsUnit.Pixel, attributes);
  
      //dispose the Graphics object
      g.Dispose();
      return newBitmap;
  }
  </code></pre>
  
  <p>Now, this is a fairly grayscale (black and white tone). I want to increase the black tone and make darker which I could do with Photoshop. Please let me know how can I achieve this in C#?</p>
  
  <p>Please let me know.</p>
  
  <p>Cheers! :)</p>