title: imagemagick get a co-ordinate for pixel with most common color
body: <p><br>
  In short, I want to find out co-ordinate of a pixel with predominant color.</p>
  
  <p>To be specific, I want to achieve the following:</p>
  
  <ol>
  <li><p>Find predominant color. By predominant, I mean a color that majority of the pixels in an image have (I have achieved it using histogram)<br></p></li>
  <li><p>After getting this color (in my case its black), I want to find a pixel that is black and its surrounded by only black pixels. Basically, the center of most concentrated area of black.</p></li>
  </ol>
  
  <p>Till now, I could only get the predominant color.</p>
  
  <pre><code>convert src.png -format %c histogram:info: &gt; x.txt
  cat x.txt | awk '{print $1}' | sed 's/://g' &gt; x1.txt
  h=$(sort -n x1.txt | tail -1)
  cat x.txt | grep "$h"
  rm -rf x.txt
  </code></pre>
  
  <p>Result:</p>
  
  <pre><code>    169211: (  0,  0,  0,255) #000000 black
  </code></pre>
  
  <p>Now, I can also get all the co-ordinates for black<br></p>
  
  <pre><code>convert src.png txt: | grep black
  469,799: (  0,  0,  0,255)  #000000  black
  470,799: (  0,  0,  0,255)  #000000  black
  471,799: (  0,  0,  0,255)  #000000  black
  472,799: (  0,  0,  0,255)  #000000  black
  473,799: (  0,  0,  0,255)  #000000  black
  474,799: (  0,  0,  0,255)  #000000  black
  475,799: (  0,  0,  0,255)  #000000  black
  476,799: (  0,  0,  0,255)  #000000  black
  477,799: (  0,  0,  0,255)  #000000  black
  478,799: (  0,  0,  0,255)  #000000  black
  ...
  </code></pre>
  
  <p>But I need a random co-ordinate of a black pixel that is located at a place where there is a only black pixels around it...<br></p>
  
  <p>I am using Linux and Imagemagick version 6.6.5</p>