(PHP 4, PHP 5)
imagecolorstotal — Find out the number of colors in an image's palette
Returns the number of colors in an image palette.
An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
Returns the number of colors in the specified image's palette or 0 for truecolor images.
Example #1 Getting total number of colors in an image using imagecolorstotal()
<?php
// Create image instance
$im = imagecreatefromgif('php.gif');
echo 'Total colors in image: ' . imagecolorstotal($im);
// Free image
imagedestroy($im);
?>
The above example will output something similar to:
Total colors in image: 128