How to do resize and color change png image in php GD

<?php
createImage(50,50, 0,0, 255);
function createImage($width, $height, $nR, $nG, $nB)
{
$image = imagecreatefrompng("source.png");
imagealphablending($image, false);  
imagesavealpha($image, true);       

      //resize the image
      $new_image = imagecreatetruecolor($width, $height);
      imagealphablending($new_image, false); 
      imagesavealpha($new_image, true);
      imagecopyresampled(开发者_如何转开发$new_image, $image, 0, 0, 0, 0, $width, $height, imagesx($image), imagesx($image));

    //colorize the image
        $nrgb = str_pad(dechex($nR), 2, '0', STR_PAD_LEFT). str_pad(dechex($nG), 2, '0', STR_PAD_LEFT). str_pad(dechex($nB), 2, '0', STR_PAD_LEFT);              

       $newColor = $nrgb;

        $c2 = sscanf($newColor ,"%2x%2x%2x");

        for($i=0;$i<$width;$i++)
        {
            for($j=0;$j<$height;$j++)
            {
             $cIndex = imagecolorat($new_image,$i,$j);

             imagecolorset($new_image,$cIndex,$c2[0],$c2[1],$c2[2]);
            }
        }

        header("Content-Type: image/png");

        imagepng($new_image,"test.png");
}
?>

No expert here... so far after one month research and hard study I found the answer for above solution......just a couple of min ago... we have to use imagecreate funciton instead of imagecreatetruecolor... coz trucolor function generate 32bit png image...we could not colorize 32 bit image using imagecolorset function.. how tricky it is....lol.. thanks for the support of crayon...