Bartlomiej Pohl

<?php
/* Classname: imageResizer
 * Filename: class.imageResizer.php
 * Author: Bartlomiej Pohl
 * Description: class for Image resizing
 */

class imageResizer {
    public $accepted_types = array();                   //Array with accepted types. Contains the mime_type, extension and function that is called to load image
    public $error_code = 0;                             //Errorcode. 0: no errors.
    public $error_ini = "../config/errors.ini";         //Inifile from which all errormessages are loaded.
    public $max_file_size = 0;                          //Sets the Maximum Filesize for sourcefiles to resize

    /* constructor: Params
     *  @images_path        :   String. Path were resized Images are copied to
     *  @load_standard_types:   Boolean. Sets if standard filetypes are used or not.
     *
     * Return: none
     */
    function __construct($load_standard_types=true) {
        if($load_standard_types == true) {
            $this->loadStandardTypes();
        }
    }

    /* Sets Max Filesize for images
     * Params
     *  @file_size: Integer. Maximum Filesize in bytes
     *
     * Return: returns false if $file_size isn't an integer value. else return true;
     */
    function setMaxFileSize($file_size) {
        if(is_integer($file_size)) {
            $this->max_file_size = $file_size;

            return true;
        }
        else {
            return false;
        }
    }

    /* Checks if image is valid. Checks with getimagesize, the array accepted_types and the filesize
     * Params
     *  @file: String. Path to Imagefile.
     *
     * Return: boolean. Returns if image is valid or not.
     */
    function imageValid($file) {
        if(file_exists($file)) {
            $file_info = pathinfo($file);
            $file_type = strtolower($file_info["extension"]);

            $accepted_type = false;

            foreach($this->accepted_types as $type) {
                if($type["extension"] == $file_type) {
                    $accepted_type = true;
                }
            }

            if($accepted_type == true) {
                if(is_array(getimagesize($file))) {
                    if($this->max_file_size != 0) {
                        if(filesize($file) <= $this->max_file_size) {
                            return true;
                        }
                        else {
                            $this->error_code = 4;

                            return false;
                        }
                    }
                    else {
                        return true;
                    }
                }
                else {
                    $this->error_code = 3;

                    return false;
                }
            }
            else {
                $this->error_code = 2;

                return false;
            }
        }
        else {
            $this->error_code = 1;

            return false;
        }
    }

    /* Loads standard imagetypes.
     *
     * Return: none
     */
    function loadStandardTypes() {
        $this->addAcceptedType("jpg","imagecreatefromjpeg","imagejpeg");
        $this->addAcceptedType("jpeg","imagecreatefromjpeg","imagejpeg");
        $this->addAcceptedType("gif","imagecreatefromgif","imagegif");
        $this->addAcceptedType("png","imagecreatefrompng","imagepng");
    }

    /* Adds imagestype and imagefunction
     * Params
     *  @extension  :   String. Specififes file extension
     *  @function   :   String. Specifies a gd-function that will be user to read the image. Example: imagecreatefromjpg, imagecreatefromgif etc.
     *
     * Return: none
     */
    function addAcceptedType($extension,$read_function,$create_function) {
        $type["extension"] = strtolower($extension);
        $type["read_function"] = $read_function;
        $type["create_function"] = $create_function;

        $this->accepted_types[] = $type;
    }
    /* Gets Errormessage for currently set Error.
     *  Params
     *   none
     *
     *  Return  :   String. errormessage. Returns false if no errormessage exists.
     */
    function getErrorMessage() {
        if($this->error_code != 0) {
            $ini_content = parse_ini_file($this->error_ini,true);

            if(isset($ini_content["image_resizer"][$this->error_code])) {
                return $ini_content["image_resizer"][$this->error_code];
            }
            else {
                return "Errormessage dosnt't exist! Errorcode: ".$this->error_code;
            }
        }
        else {
            return false;
        }
    }

    /*
     * Validates and resizes Image to specific size. uses Method resizeImage.
     * Params
     *  @source_file        :       String. File to be resized
     *  @destination_file   :       String. Path to new Image
     *  @new_width          :       Integer. Specifies the width for the new image
     *  @new_height         :       Integer. Specifies the height for the new image
     *
     * return   :   boolean. returns false if an error occurs.
     */
    function resizeFixed($source_file,$destination_file,$new_width,$new_height) {
        if($this->imageValid($source_file) == true) {
            if($this->resizeImage($source_file,$destination_file,$new_width,$new_height) == true) {
                return true;
            }
            else {
                return false;
            }
        }
        else {
            return false;
        }
    }

    /*
     * Validates and resizes Image proportional to specific width. uses Method resizeImage.
     * Params
     *  @source_file            :       String. File to be resized
     *  @destination_file       :       String. Path to new Image
     *  @new_width              :       Integer. Specifies the width for the new image
     *
     * Return   :   boolean. returns false if an error occurs.
     */
    function resizeByWidth($source_file,$destination_file,$new_width) {
        if($this->imageValid($source_file)) {
            $dimensions = getimagesize($source_file);

            $width = $dimensions[0];
            $height = $dimensions[1];

            $resize_factor = $width / $new_width;
            $new_height = round($height / $resize_factor);

            if($this->resizeImage($source_file,$destination_file,$new_width,$new_height) == true) {
                return true;
            }
            else {
                return false;
            }
        }
        else {
            return false;
        }
    }

    /*
     * Validates and resizes Image proportional to specific height. uses Method resizeImage.
     * Params
     *  @source_file            :       String. File to be resized
     *  @destination_file       :       String. Path to new Image
     *  @new_height             :       Integer. Specifies the height for the new image
     *
     * Return   :   boolean. returns false if an error occurs.
     */
    function resizeByHeight($source_file,$destination_file,$new_height) {
        if($this->imageValid($source_file)) {
            $dimensions = getimagesize($source_file);

            $width = $dimensions[0];
            $height = $dimensions[1];

            $resize_factor = $height / $new_height;
            $new_width = round($width / $resize_factor);

            if($this->resizeImage($source_file,$destination_file,$new_width,$new_height) == true) {
                return true;
            }
            else {
                return false;
            }
        }
        else {
            return false;
        }
    }

    /* resizes images to specific size. uses gd library.
     * Params
     *  @pfile      :   String. specifies the sourcefile.
     *  @pdst_path  :   String. specifies the output file.
     * Return   : boolean. Returns if resizing was successful
     */
    function resizeImage($pfile,$pdst_path,$pwidth,$pheight) {
        $file_info = pathinfo($pfile);
        $file_type = strtolower($file_info["extension"]);

        foreach($this->accepted_types as $type) {
            if($type["extension"] == $file_type) {
                eval('$img_src = '.$type["read_function"].'($pfile);');
            }
        }

        $dimensions = getimagesize($pfile);

        $img_src_width = $dimensions[0];
        $img_src_height = $dimensions[1];
        $dst = ImageCreateTrueColor($pwidth,$pheight);

        imagecopyresampled($dst,$img_src,0,0,0,0,$pwidth,$pheight,$img_src_width,$img_src_height);

        foreach($this->accepted_types as $type) {
            if($type["extension"] == $file_type) {
                eval('$img = '.$type["create_function"].'($dst,$pdst_path,100);');
            }
        }

        if(imagejpeg($dst,$pdst_path,100)) {
            imagedestroy($dst);
            imagedestroy($img_src);
            return true;
        }
        else {
            return false;
        }
    }
}


if(isset($_FILES["image"])) {
    move_uploaded_file($_FILES["image"]["tmp_name"],$_FILES["image"]["name"]);

    $test = new imageResizer();
    $test->setMaxFileSize(5000000);

    if($test->resizeByHeight($_FILES["image"]["name"],"test.jpg",160) != true) {
        echo $test->getErrorMessage();
    }
}



?>

<form action="class.imageResizer.php" method="POST" enctype="multipart/form-data">
<input type="file" name="image" />
<input type="submit" value="hoch damit"/>
</form>