Image Resizer

Image.php

<?php

class Image
{
	public static function resize($path, $new_width, $new_height)
	{
	  	list($width, $height) = getimagesize($path);
	  	
	  	if ($new_width > max( $width, $height ) && $new_height > max($width, $height))
	  		return;

	  	$type = strtolower(substr(strrchr($path, "."), 1));

	  	$ratio = max( $width / $new_width, $height / $new_height );

	  	$new_width = $width / $ratio;
	  	$new_height = $height / $ratio;

	  	switch($type) {
		    case 'bmp': $src = imagecreatefromwbmp($path); break;
		    case 'gif': $src = imagecreatefromgif($path); break;
		    case 'jpg': $src = imagecreatefromjpeg($path); break;
		    case 'png': $src = imagecreatefrompng($path); break;
		    default : return "Unsupported picture type!";
		}

	    $dst = imagecreatetruecolor($new_width, $new_height);

	      // preserve transparency
		if($type == "gif" or $type == "png"){
			imagecolortransparent($dst, imagecolorallocatealpha($dst, 0, 0, 0, 127));
			imagealphablending($dst, false);
			imagesavealpha($dst, true);
		}

	    imagecopyresampled($dst, $src, 0, 0, 0, 0, $new_width, $new_height, $width, $height);

	    switch($type) {
		    case 'bmp': imagewbmp($dst, $path); break;
		    case 'gif': imagegif($dst, $path); break;
		    case 'jpg': imagejpeg($dst, $path); break;
		    case 'png': imagepng($dst, $path, 9); break;
		}

	    return true;
	}

	public static function resizeDirectory($directory, $new_width, $new_height)
	{
		$images =  glob($directory."*.{jpg,gif,png}", GLOB_BRACE);

		foreach ($images as $image) {
			Image::resize($image, $new_width, $new_height);
		}
	}
}

// Resize whole directory
$images_path = __DIR__ . '/path/to/directory/';
Image::resizeDirectory($images_path, 220, 80);