How to find the Dominant color in image?

Question

i want to find the dominant color in image, how can i do it ?

it would be great if i can get this in HEX code (exm: #eeeeee)

Answer 1

To find the most "dominant" color in an image, meaning the color that is most prevalent in the image: you'd need to create a histogram of the image.

Here is an the code from this article on how to create a histogram in PHP. (Website has gone off line several times)

<?php $source_file = "test_image.jpg";  // histogram options  $maxheight = 300; $barwidth = 2;  $im = ImageCreateFromJpeg($source_file);  $imgw = imagesx($im); $imgh = imagesy($im);  // n = total number or pixels  $n = $imgw*$imgh;  $histo = array();  for ($i=0; $i<$imgw; $i++) {         for ($j=0; $j<$imgh; $j++)         {                  // get the rgb value for current pixel                  $rgb = ImageColorAt($im, $i, $j);                  // extract each value for r, g, b                  $r = ($rgb >> 16) & 0xFF;                 $g = ($rgb >> 8) & 0xFF;                 $b = $rgb & 0xFF;                  // get the Value from the RGB value                  $V = round(($r + $g + $b) / 3);                  // add the point to the histogram                  $histo[$V] += $V / $n;          } }  // find the maximum in the histogram in order to display a normated graph  $max = 0; for ($i=0; $i<255; $i++) {         if ($histo[$i] > $max)         {                 $max = $histo[$i];         } }  echo "<div style='width: ".(256*$barwidth)."px; border: 1px solid'>"; for ($i=0; $i<255; $i++) {         $val += $histo[$i];          $h = ( $histo[$i]/$max )*$maxheight;          echo "<img src=\"img.gif\" width=\"".$barwidth."\" height=\"".$h."\" border=\"0\">"; } echo "</div>"; ?>  

In that example $max is your most "dominant" color.

Answer 2

There is a PHP class developed that handles this, named color extract. However, know that doing this on the server side will require substantial system resources. You may wish to instead do this with canvas.