<code lang="php">function image_create_thumb($filename, $width, $height)
{
	list($image["Width"], $image["Height"], $image["Type"]) = getimagesize($filename);

	if($image["Type"] == IMG_JPG || $image["Type"] == IMG_JPEG)
	{
		$im_image = ImageCreateFromJPEG($filename);
	}
	if($image["Type"] == IMG_GIF)
	{
		$im_image = ImageCreateFromGIF($filename);
	}
	if($image["Type"] == IMG_PNG)
	{
		$im_image = ImageCreateFromPNG($filename);
	}

	if($image["Width"] > $image["Height"])
	{
		$scale = $width / $image["Width"];
		$thumb_width = $width;
		$thumb_height  = floor($image["Height"]*$scale);
	}
	else
	{
		$scale = $height / $image["Height"];
		$thumb_height = $height;
		$thumb_width  = floor($image["Width"]*$scale);
	}

	$im_thumb = @ImageCreateTrueColor($thumb_width, $thumb_height) or die("Cannot Initialize new GD image stream");

	ImageCopyResized($im_thumb,$im_image,0,0,0,0,$thumb_width,$thumb_height,$image["Width"],$image["Height"]);

	ImageDestroy($im_image);
	ImagePNG($im_thumb, $filename);
	ImageDestroy($im_thumb);

	return true;
}//image_create_thumb($filename, $width, $height)</code>