title: Remove filter on image
body: <p>I'm using AForge.net for my channel filtering, I have 3 button, red, blue and green.
  When I click on button red it will apply the filter of red channel. However, when I go on to click on the blue button, it will overlap the red and image goes dark. </p>
  
  <p>Does anyone know how can I "dispose" red channel when blue is click, vice versa, so as the filter will not overlap each other? Below is a snippet of my code.</p>
  
  <pre><code> private void redchannel_Click_1(object sender, EventArgs e)
      {
          try
          {
  
              pictureBox1.Image = pic;
              pictureBox2.Image = pic2;
  
              // create filter
              ChannelFiltering filter = new ChannelFiltering();
              // set channels' ranges to keep
              filter.Red = new IntRange(0, 255);
              filter.Green = new IntRange(255, 255);
              filter.Blue = new IntRange(255, 255);
              // apply the filter
              filter.ApplyInPlace(pic2);
  
  
          }
  
  
          catch (Exception)
          {
              throw new ApplicationException("Failed loading image");
          }
      }
  
      private void bluechannel_Click_1(object sender, EventArgs e)
      {
          try
          {
              pictureBox1.Image = pic;
              pictureBox2.Image = pic2;
  
              // create filter
              ChannelFiltering filter = new ChannelFiltering();
              // set channels' ranges to keep
              filter.Red = new IntRange(255, 255);
              filter.Green = new IntRange(255, 255);
              filter.Blue = new IntRange(0, 255);
              // apply the filter
              filter.ApplyInPlace(pic2);
  
          }
  
  
  
  
          catch (Exception)
          {
              throw new ApplicationException("Failed loading image");
          }
      }
  
      private void greenchannel_Click_1(object sender, EventArgs e)
      {
          try
          {
              pictureBox1.Image = pic;
              pictureBox2.Image = pic2;
  
              // create filter
              ChannelFiltering filter = new ChannelFiltering();
              // set channels' ranges to keep
  
              filter.Red = new IntRange(255, 255);
              filter.Green = new IntRange(0, 255);
              filter.Blue = new IntRange(255, 255);
              // apply the filter
              filter.ApplyInPlace(pic2);
          }
          catch (Exception)
          {
              throw new ApplicationException("Failed loading image");
  
          }
      }
  </code></pre>