Pixelate Images using PHP

On January 24th, 2011 "lasers" from Stack Overflow asked how can he make the edges smoother on an image. Effectively, the script he uses to generate to pixelate image has very sharp edges. After some digging, I found a very good script. This script generates a pixelate image with smooth edges and sharp edges.

The smooth edges look way better for my taste and here's what kept from the script:

function convertToPixel($image, $size) {
 $im = imagecreatefromjpeg($image);
 $size = (int)$size;
 $sizeX = imagesx($im);
 $sizeY = imagesy($im);
 if($sizeX < 3 && $sizeX < 3) { // or you can choose any size you want
  return;
 }
 for($i = 0;$i < $sizeX; $i += $size) {
  for($j = 0;$j < $sizeY; $j += $size) {
  $colors = Array('alpha' => 0, 'red' => 0, 'green' => 0, 'blue' => 0, 'total' => 0);
   for($k = 0; $k < $size; ++$k) {
    for($l = 0; $l < $size; ++$l) {
     if($i + $k >= $sizeX || $j + $l >= $sizeY) {
      continue;
     }
     $color = imagecolorat($im, $i + $k, $j + $l);
     imagecolordeallocate($im, $color);
     $colors['alpha'] += ($color >> 24) & 0xFF;
     $colors['red'] += ($color >> 16) & 0xFF;
     $colors['green'] += ($color >> 8) & 0xFF;
     $colors['blue'] += $color & 0xFF;
     ++$colors['total'];
    }
   }
   $color = imagecolorallocatealpha($im, $colors['red'] / $colors['total'], $colors['green'] / $colors['total'], $colors['blue'] / $colors['total'], $colors['alpha'] / $colors['total']);
   imagefilledrectangle($im, $i, $j, ($i + $size - 1), ($j + $size - 1), $color);
  }
 }
 header('Content-type: image/jpg');
 imagejpeg($im, '', 100);
}
$image = 'lion.jpg';
convertToPixel($image, 10);

This will convert this image:

To:

If you want to change the pixel size you can simply change the second parameters to a lower or higher number.