/admin/includes/modules/ImageResize.class.php

<?php



   # ========================================================================#

   #

   #  Author:    Jarrod Oberto

   #  Version:	 1.0

   #  Date:      17-Jan-10

   #  Purpose:   Resizes and saves image

   #  Requires : Requires PHP5, GD library.

   #  Usage Example:

   #                     include("classes/resize_class.php");

   #                     $resizeObj = new ImageResize('images/cars/large/input.jpg');

   #                     $resizeObj -> resizeImage(150, 100, 0); 

   #                     $resizeObj -> saveImage('images/cars/large/output.jpg', 100);

   #

   #

   # ========================================================================#





		Class ImageResize{

			// *** Class variables

			private $image;

		    private $width;

		    private $height;

			private $imageResized;



			function __construct($fileName)

			{

				// *** Open up the file

				$this->image = $this->openImage($fileName);



			    // *** Get width and height

			    $this->width  = imagesx($this->image);

			    $this->height = imagesy($this->image);

			}



			## --------------------------------------------------------



			private function openImage($file)

			{

				// *** Get extension

				$extension = strtolower(strrchr($file, '.'));



				switch($extension)

				{

					case '.jpg':

					case '.jpeg':

						$img = @imagecreatefromjpeg($file);

						break;

					case '.gif':

						$img = @imagecreatefromgif($file);

						break;

					case '.png':

						$img = @imagecreatefrompng($file);

						break;

					default:

						$img = false;

						break;

				}

				return $img;

			}



			## --------------------------------------------------------



			public function resizeImage($newWidth, $newHeight, $option="auto")

			{

				// *** Get optimal width and height - based on $option

				$optionArray = $this->getDimensions($newWidth, $newHeight, $option);



				$optimalWidth  = $optionArray['optimalWidth'];

				$optimalHeight = $optionArray['optimalHeight'];





				// *** Resample - create image canvas of x, y size

				$this->imageResized = imagecreatetruecolor($optimalWidth, $optimalHeight);

				imagecopyresampled($this->imageResized, $this->image, 0, 0, 0, 0, $optimalWidth, $optimalHeight, $this->width, $this->height);





				// *** if option is 'crop', then crop too

				if ($option == 'crop') {

					$this->crop($optimalWidth, $optimalHeight, $newWidth, $newHeight);

				}

			}



			## --------------------------------------------------------

			

			private function getDimensions($newWidth, $newHeight, $option)

			{



			   switch ($option)

				{

					case 'exact':

						$optimalWidth = $newWidth;

						$optimalHeight= $newHeight;

						break;

					case 'portrait':

						$optimalWidth = $this->getSizeByFixedHeight($newHeight);

						$optimalHeight= $newHeight;

						break;

					case 'landscape':

						$optimalWidth = $newWidth;

						$optimalHeight= $this->getSizeByFixedWidth($newWidth);

						break;

					case 'auto':

						$optionArray = $this->getSizeByAuto($newWidth, $newHeight);

						$optimalWidth = $optionArray['optimalWidth'];

						$optimalHeight = $optionArray['optimalHeight'];

						break;

					case 'crop':

						$optionArray = $this->getOptimalCrop($newWidth, $newHeight);

						$optimalWidth = $optionArray['optimalWidth'];

						$optimalHeight = $optionArray['optimalHeight'];

						break;

				}

				return array('optimalWidth' => $optimalWidth, 'optimalHeight' => $optimalHeight);

			}



			## --------------------------------------------------------



			private function getSizeByFixedHeight($newHeight)

			{

				$ratio = $this->width / $this->height;

				$newWidth = $newHeight * $ratio;

				return $newWidth;

			}



			private function getSizeByFixedWidth($newWidth)

			{

				$ratio = $this->height / $this->width;

				$newHeight = $newWidth * $ratio;

				return $newHeight;

			}



			private function getSizeByAuto($newWidth, $newHeight)

			{

				if ($this->height < $this->width)

				// *** Image to be resized is wider (landscape)

				{

					$optimalWidth = $newWidth;

					$optimalHeight= $this->getSizeByFixedWidth($newWidth);

				}

				elseif ($this->height > $this->width)

				// *** Image to be resized is taller (portrait)

				{

					$optimalWidth = $this->getSizeByFixedHeight($newHeight);

					$optimalHeight= $newHeight;

				}

				else

				// *** Image to be resizerd is a square

				{

					if ($newHeight < $newWidth) {

						$optimalWidth = $newWidth;

						$optimalHeight= $this->getSizeByFixedWidth($newWidth);

					} else if ($newHeight > $newWidth) {

						$optimalWidth = $this->getSizeByFixedHeight($newHeight);

						$optimalHeight= $newHeight;

					} else {

						// *** Sqaure being resized to a square

						$optimalWidth = $newWidth;

						$optimalHeight= $newHeight;

					}

				}



				return array('optimalWidth' => $optimalWidth, 'optimalHeight' => $optimalHeight);

			}



			## --------------------------------------------------------



			private function getOptimalCrop($newWidth, $newHeight)

			{



				$heightRatio = $this->height / $newHeight;

				$widthRatio  = $this->width /  $newWidth;



				if ($heightRatio < $widthRatio) {

					$optimalRatio = $heightRatio;

				} else {

					$optimalRatio = $widthRatio;

				}



				$optimalHeight = $this->height / $optimalRatio;

				$optimalWidth  = $this->width  / $optimalRatio;



				return array('optimalWidth' => $optimalWidth, 'optimalHeight' => $optimalHeight);

			}



			## --------------------------------------------------------



			private function crop($optimalWidth, $optimalHeight, $newWidth, $newHeight)

			{

				// *** Find center - this will be used for the crop

				$cropStartX = ( $optimalWidth / 2) - ( $newWidth /2 );

				$cropStartY = ( $optimalHeight/ 2) - ( $newHeight/2 );



				$crop = $this->imageResized;

				//imagedestroy($this->imageResized);



				// *** Now crop from center to exact requested size

				$this->imageResized = imagecreatetruecolor($newWidth , $newHeight);

				imagecopyresampled($this->imageResized, $crop , 0, 0, $cropStartX, $cropStartY, $newWidth, $newHeight , $newWidth, $newHeight);

			}



			## --------------------------------------------------------



			public function saveImage($savePath, $imageQuality="100")

			{

				// *** Get extension

        		$extension = strrchr($savePath, '.');

       			$extension = strtolower($extension);



				switch($extension)

				{

					case '.jpg':

					case '.jpeg':

						if (imagetypes() & IMG_JPG) {

							imagejpeg($this->imageResized, $savePath, $imageQuality);

						}

						break;



					case '.gif':

						if (imagetypes() & IMG_GIF) {

							imagegif($this->imageResized, $savePath);

						}

						break;



					case '.png':

						// *** Scale quality from 0-100 to 0-9

						$scaleQuality = round(($imageQuality/100) * 9);



						// *** Invert quality setting as 0 is best, not 9

						$invertScaleQuality = 9 - $scaleQuality;



						if (imagetypes() & IMG_PNG) {

							 imagepng($this->imageResized, $savePath, $invertScaleQuality);

						}

						break;



					// ... etc



					default:

						// *** No extension - No save.

						break;

				}



				imagedestroy($this->imageResized);

			}





			## --------------------------------------------------------



		}

?>