<?php
/*

Thumbnailer
Copyright © 2009 Federman Scripts
Author: David Federman
Website: http://federmanscripts.com

This PHP is freely available for public use and modification, but
please give credit where credit is due.

*/

class thumbnailer
{
	private $src;
	private $width;
	private $height;
	private $mime;
	
	public function __construct($src)
	{
		$this->src = $src;
		
		$info = getimagesize($this->src);
		$this->width = $info[0];
		$this->height = $info[1];
		$this->mime = $info['mime'];
	}
	
	public function makeThumbnail($maxW, $maxH, $out = null, $quality = null)
	{
		// find new height and width
		$dh = $this->height - $maxH; // difference in h
		$dw = $this->width - $maxW; // difference in w
		
		// create old image
		if($this->mime == "image/jpeg")
			$srcImg = imagecreatefromjpeg($this->src);
		elseif($this->mime == "image/gif")
			$srcImg = imagecreatefromgif($this->src);
		elseif($this->mime == "image/png")
			$srcImg = imagecreatefrompng($this->src);
		
		if($dh > 0 || $dw > 0) // if doesn't fit in bounding box, resize
		{
			if($dw < $dh) // resize height
			{
				$nh = $maxH;
				$nw = $maxH * ($this->width / $this->height);
			}
			else // resize width
			{
				$nw = $maxW;
				$nh = $maxW * ($this->height / $this->width);
			}
			
			// create new image
			$newImg = imagecreatetruecolor($nw, $nh);
			
			// resize
			imagecopyresized($newImg, $srcImg, 0, 0, 0, 0, $nw, $nh, $this->width, $this->height);
		}
		else // no resize needed
			$newImg = $srcImg;
		
		// output
		if(empty($out)) // if to browser
		{
			header('Content-type: ' . $this->mime);
		}

		if($this->mime == "image/jpeg")
			if(!empty($quality))
				imagejpeg($newImg, $out, $quality);
			else
				imagejpeg($newImg, $out);
		elseif($this->mime == "image/gif")
			imagegif($newImg, $out);
		elseif($this->mime == "image/png")
			imagepng($newImg, $out);
	}
}

// if this was requested directly, run on query string
if($_SERVER['SCRIPT_FILENAME'] == __FILE__)
{
	// get variables if needed
	$src = $_GET['src'];
	$maxH = $_GET['maxH'];
	$maxW = $_GET['maxW'];
	$out = $_GET['out'];
	$quality = $_GET['q'];
	
	// if these not set, just stop
	if(!isset($src) || !isset($maxH) || !isset($maxW))
		die();
	
	$thumbnailer = new thumbnailer($src);
	$thumbnailer->makeThumbnail($maxW, $maxH, $out, $quality);
}
?>