Ridimensionare immagini PNG con librerie GD

[brodik]

ma l'hai provato ad usare almeno?

$new_image = imagecreatetruecolor($width, $height);
imagealphablending($new_image, false);
imagesavealpha($new_image, true);  

$src_image = imagecreatefrompng($file);
imagealphablending($src_image, true);

imagecopyresized($new_image, $src_image, 0, 0, 0, 0, $width, $height, imagesx($src_image), imagesy($src_image)); // oppure imagecopyresampled()
imagepng($new_image, $name_new_image);