title: Emgu CV - Combining greyscale images into single Bgr image
body: <p>I'm trying to convert a greyscale image to a Hsv image, but with the S and V channels set to a preset value. The following code works but takes ~400ms to execute. </p>
  
  <pre><code>public void ToHueImage(this Image&lt;Gray, double&gt; image, Image&lt;Hsv, double&gt; output)
  {
          for (int i = 0; i &lt; image.Width; i++)
          {
              for (int j = 0; j &lt; image.Height; j++)
              {
                  output.Data[j, i, 0] = image.Data[j, i, 0];
                  output.Data[j, i, 1] = 255;
                  output.Data[j, i, 2] = 255;
              }
          }           
      }
  }
  </code></pre>
  
  <p>I would like to be able to assign a single greyscale image channel to each of the H, S, and V planes in a single operation to avoid copying the pixels across individually, something along the lines of</p>
  
  <pre><code>public void ToHueImage(this Image&lt;Gray, double&gt; image, Image&lt;Hsv, double&gt;     output)
  {
      output.Data.H = image; 
      output.Data.S = WHITE_IMAGE; // These are static
      output.Data.V = WHITE_IMAGE; // These are static            
  }
  </code></pre>
  
  <p>without resorting to byte copying etc. I'm trying to get the execution time to ~30ms or so. Is there any straightforward way to accomplish this? </p>