PHP Fill or Fit Image (based on gd library)

php_GDImageFill.php

<?php

namespace common\widgets;

/**
* Crop fill or fit image with php-gd library
* @author Maxim Ishchenko <maxim.ishchenko@gmail.com>
* @version 1.0*
* @uses, @example
* @license GPL
* @license http://opensource.org/licenses/gpl-license.php GNU Public License
*
* $image = new ImageFill(
* 		array(
* 				'source' => 'source.jpg', 	// required source image
* 				'h' => 250,					// optional, if missing uses ImageFill::DEFAULT_HEIGHT value
* 				'w' => 250,					// optional, if missing uses ImageFill::DEFAULT_WIDTH value
* 				'mode' => 'fill', 			// optional, must be 'fit' or 'fill', default 'fill'
* 				'saveFile' => false, 		// optional, is need to save file, default - true, must be boolean, file be saved into ImageFill::DESTINATION_PATH
* 			)
* 	);
*
* @property string $source
* @property integer $h
* @property integer $w
* @property string $mode
* @property bool $saveFile
*/
class ImageFill
{
	/**
	 * @constant MIN_HEIGHT minimal image height
	 * @constant MIN_WIDTH minimal image width
	 * @constant MAX_HEIGHT maximum available image height
	 * @constant MAX_WIDTH maximum available image width
	 * @constant DEFAULT_WIDTH standart image width
	 * @constant DEFAULT_HEIGHT standart image height
	 * @constant DEFAULT_MODE standart mode (if not set in $args array)
	 * @constant DESTINATION_PATH path to save output images (if $saveFile argument is true)
	 */
	const MIN_HEIGHT = 1;
	const MIN_WIDTH = 1;
	const MAX_HEIGHT = 1000;
	const MAX_WIDTH = 1000;
	const DEFAULT_HEIGHT = 100;
	const DEFAULT_WIDTH = 100;
	const DEFAULT_MODE = 'fill';
	const DESTINATION_PATH = 'images/output.jpg';

	/**
	 * @access private
	 * @property integer $h
	 * @property integer $w
	 * @property bool $saveFile
	 * @property string $mode
	 * @property string $source
	 * @property array $availableModes
	 */
	private $h;
	private $w;
	private $saveFile;
	private $mode;
	private $source;
	private $availableModes = array('fit', 'fill');
	
	function __construct($args = array())
	{
		/**
		 * source required
		 * @property string $source
		 * @access private
		 * @return Exception if not set or image resourse if variable is set
		 */
		if(!isset($args['source'])) {
			throw new Exception("FillImage. One or more required parameters are missing!", 1);			
		} else {

			/**
			 * @link http://php.net/manual/ru/function.imagecreatefromjpeg.php
			 */
			$this->source = imagecreatefromjpeg($args['source']);
		}

		/**
		 * Set default source value to DEFAULT_MODE constant if $mode is not set
		 * Check if mode is in range (fit, fill)
		 * @constant DEFAULT_MODE
		 * @property string $mode
		 * @access private
		 * @return Exception if not in range from $availableModes array, else return pre-defined value
		 */
		if(isset($args['mode']) && !in_array($args['mode'], $this->availableModes)) {
			throw new Exception("FillImage. Incorrect mode!", 1);	
		} else {
			$this->mode = (isset($args['mode']) && $args['mode'] == 'fit') ? 'fit' : self::DEFAULT_MODE;
		}

		/**
		 * Check if isset $saveFile, is $saveFile is boolean and set it to true if not set
		 * @property bool $saveFile
		 * @access private
		 * @return true | false
		 */
		if($args['saveFile'] !== null && !is_bool($args['saveFile'])) {
			throw new Exception("Incorrect saveFile value", 1);
		} elseif($args['saveFile'] !== null && is_bool($args['saveFile'])) {
			$this->saveFile = $args['saveFile'];
		} else {
			$this->saveFile = true;
		}
		
		/**
		 * Check if isset $h value. If not set it to DEFAULT_HEIGHT
		 * Alse check if $h value in range (MIN_HEIGHT, MAX_HEIGHT), if not - set to DEFAULT_HEIGHT
		 * @constant MIN_HEIGHT
		 * @constant MIN_WIDTH
		 * @constant MAX_HEIGHT
		 * @constant MAX_WIDTH
		 * @property integer $h
		 * @access private
		 * @return integer $h value from $args array if it set or set $h to DEFAULT_HEIGHT value
		 */
		if(isset($args['h'])) {

			/**
			 * @link http://php.net/manual/ru/function.intval.php
			 */
			$this->h = intval($args['h']);
			$this->h = ($this->h <= self::MIN_HEIGHT || $this->h >= self::MAX_HEIGHT) ? self::DEFAULT_HEIGHT : $this->h;
		} else {
			$this->h = self::DEFAULT_HEIGHT;
		}

		/**
		 * Check if isset $w value. If not set it to DEFAULT_HEIGHT
		 * Alse check if $w value in range (MIN_HEIGHT, MAX_HEIGHT), if not - set to DEFAULT_HEIGHT
		 * @constant MIN_WIDTH
		 * @constant MAX_WIDTH
		 * @constant DEFAULT_WIDTH
		 * @property integer $w
		 * @access private
		 * @return integer $w value from $args array if it set or set $w to DEFAULT_HEIGHT value
		 */
		if(isset($args['w'])) {

			/**
			 * @link http://php.net/manual/ru/function.intval.php
			 */
			$this->w = intval($args['w']);
			$this->w = ($this->w <= self::MIN_WIDTH || $this->w >= self::MAX_WIDTH) ? self::DEFAULT_WIDTH : $this->w;
		} else {
			$this->w = self::DEFAULT_WIDTH;
		}

		/**
		 * Run result function to get croped-image
		 * @see getDestinationImage()
		 */
		$this->getDestinationImage();
	}

	/**
	 * @access private
	 * @constant DEFAULT_MODE
	 * @property string $source
	 * @param string $dst_image
	 * @var integer $new_width
	 * @var integer $new_height
	 * @var integer $new_x
	 * @var integer $new_y
	 * @var integer $next
	 * @var integer $dst_width
	 * @var integer $src_height
	 * @var integer $src_width
	 * @var integer $dst_height
	 * @var string $dst_image
	 */
	private function scaleImage($dst_image) 
	{
		/**
		 * Get source image width
		 * @link http://php.net/manual/ru/function.imagesx.php
		 */
	    $src_width = imagesx($this->source);

	    /**
	     * Get source image height
	     * @link http://php.net/manual/ru/function.imagesy.php
	     */
	    $src_height = imagesy($this->source);
	 
	 	/**
	 	 * Get destination image width
		 * @link http://php.net/manual/ru/function.imagesx.php
	 	 */
	    $dst_width = imagesx($dst_image);

	    /**
	     * Get destination image height
	     */
	    $dst_height = imagesy($dst_image);
	 
	    /**
	     * Try to match destination image by width
	     * @link http://php.net/manual/ru/function.imagesy.php
	     */
	    $new_width = $dst_width;
	    $new_height = round($new_width*($src_height/$src_width));
	    $new_x = 0;

	    /**
	     * @link http://php.net/manual/ru/function.round.php
	     */
	    $new_y = round(($dst_height-$new_height)/2);
	 
	    $next = $this->mode == self::DEFAULT_MODE ? $new_height < $dst_height : $new_height > $dst_height;
	 
	    /**
	     * If match by width failed and destination image does not fit, try by height 
	     */
	    if ($next) {
	        $new_height = $dst_height;

	        /**
	         * @link http://php.net/manual/ru/function.round.php
	         */
	        $new_width = round($new_height*($src_width/$src_height));
	        $new_x = round(($dst_width - $new_width)/2);
	        $new_y = 0;
	    }
	 
	    /**
	     * Copy image on right place
	     * @link http://php.net/manual/ru/function.imagecopyresampled.php
	     */
	    imagecopyresampled($dst_image, $this->source , $new_x, $new_y, 0, 0, $new_width, $new_height, $src_width, $src_height);
	}

	/**
	 * Return destination image to browser or save it to file
	 * @access private
	 * @property integer $w
	 * @property integer $h
	 * @property bool $saveFile
	 * @param string $dst
	 */
	private function getDestinationImage()
	{
		/**
		 * @link http://php.net/manual/ru/function.imagecreatetruecolor.php
		 */
		$dst = imagecreatetruecolor($this->w, $this->h);

		/**
		 * @link http://php.net/manual/ru/function.imagefill.php
		 */
		imagefill($dst, 0, 0, imagecolorallocate($dst, 255, 255, 255));
		 
		/**
		 * @see $scaleImage
		 */
		$this->scaleImage($dst);

		/**
		 * Output to the browser
		 * @link http://php.net/manual/ru/function.imagejpeg.php
		 */
		imagejpeg($dst, ($this->saveFile) ? self::DESTINATION_PATH : null);
	}

}

// Header('Content-Type: image/jpeg');

/**
 * @see ImageFill()
 */
// $image = new ImageFill(
// 		array(
// 				'h' => 250,
// 				'w' => 250,
// 				'source' => 'source.jpg',
// 				'mode' => 'fill',
// 				'saveFile' => false,
// 			)
// 	);