<?php/** * 图片处理，生成缩略图和添加水印图片 * Created by PhpStorm. * User: andy * Date: 17-1-3 * Time: 上午11:55 */class Image{    //原图    private $imgPath;   //图片地址    private $width;     //图片宽度    private $height;    //图片高度    private $type;      //图片类型    private $img;       //图片(图像流)    //缩略图    private $newImg;    //缩略图(图像流)    private $newWidth;    private $newHeight;    //水印图路径    private $waterMarkPath;    //输出图像质量,jpg有效    private $quality;    /**     * Image constructor.     * @param string $imagePath 图片路径     * @param string $markPath 水印图片路径     * @param int $new_width 缩略图宽度     * @param int $new_height 缩略图高度     * @param int $quality JPG图片格输出质量     */    public function __construct(string $imagePath,                                string $markPath = null,                                int $new_width = null,                                int $new_height = null,                                int $quality = 75)    {        $this->imgPath = $_SERVER[‘DOCUMENT_ROOT‘] . $imagePath;        $this->waterMarkPath = $markPath;        $this->newWidth = $new_width ? $new_width : $this->width;        $this->newHeight = $new_height ? $new_height : $this->height;        $this->quality = $quality ? $quality : 75;        list($this->width, $this->height, $this->type) = getimagesize($this->imgPath);        $this->img = $this->_loadImg($this->imgPath, $this->type);        //生成缩略图        $this->_thumb();        //添加水印图片        if (!empty($this->waterMarkPath)) $this->_addWaterMark();        //输出图片        $this->_outputImg();    }    /**     *图片输出     */    private function _outputImg()    {        switch ($this->type) {            case 1: // GIF                imagegif($this->newImg, $this->imgPath);                break;            case 2: // JPG                if (intval($this->quality) < 0 || intval($this->quality) > 100) $this->quality = 75;                imagejpeg($this->newImg, $this->imgPath, $this->quality);                break;            case 3: // PNG                imagepng($this->newImg, $this->imgPath);                break;        }        imagedestroy($this->newImg);        imagedestroy($this->img);    }    /**     * 添加水印     */    private function _addWaterMark()    {        $ratio = 1 / 5; //水印缩放比率        $Width = imagesx($this->newImg);        $Height = imagesy($this->newImg);        $n_width = $Width * $ratio;        $n_height = $Width * $ratio;        list($markWidth, $markHeight, $markType) = getimagesize($this->waterMarkPath);        if ($n_width > $markWidth) $n_width = $markWidth;        if ($n_height > $markHeight) $n_height = $markHeight;        $Img = $this->_loadImg($this->waterMarkPath, $markType);        $Img = $this->_thumb1($Img, $markWidth, $markHeight, $markType, $n_width, $n_height);        $markWidth = imagesx($Img);        $markHeight = imagesy($Img);        imagecopyresampled($this->newImg, $Img, $Width - $markWidth - 10, $Height - $markHeight - 10, 0, 0, $markWidth, $markHeight, $markWidth, $markHeight);        imagedestroy($Img);    }    /**     * 缩略图(按等比例,根据设置的宽度和高度进行裁剪)     */    private function _thumb()    {        //如果原图本身小于缩略图，按原图长高        if ($this->newWidth > $this->width) $this->newWidth = $this->width;        if ($this->newHeight > $this->height) $this->newHeight = $this->height;        //背景图长高        $gd_width = $this->newWidth;        $gd_height = $this->newHeight;        //如果缩略图宽高，其中有一边等于原图的宽高，就直接裁剪        if ($gd_width == $this->width || $gd_height == $this->height) {            $this->newWidth = $this->width;            $this->newHeight = $this->height;        } else {            //计算缩放比率            $per = 1;            if (($this->newHeight / $this->height) > ($this->newWidth / $this->width)) {                $per = $this->newHeight / $this->height;            } else {                $per = $this->newWidth / $this->width;            }            if ($per < 1) {                $this->newWidth = $this->width * $per;                $this->newHeight = $this->height * $per;            }        }        $this->newImg = $this->_CreateImg($gd_width, $gd_height, $this->type);        imagecopyresampled($this->newImg, $this->img, 0, 0, 0, 0, $this->newWidth, $this->newHeight, $this->width, $this->height);    }    /**     * 缩略图(按等比例)     * @param resource $img 图像流     * @param int $width     * @param int $height     * @param int $type     * @param int $new_width     * @param int $new_height     * @return resource     */    private function _thumb1($img, $width, $height, $type, $new_width, $new_height)    {        if ($width < $height) {            $new_width = ($new_height / $height) * $width;        } else {            $new_height = ($new_width / $width) * $height;        }        $newImg = $this->_CreateImg($new_width, $new_height, $type);        imagecopyresampled($newImg, $img, 0, 0, 0, 0, $new_width, $new_height, $width, $height);        return $newImg;    }    /**     * 加载图片     * @param string $imgPath     * @param int $type     * @return resource     */    private function _loadImg($imgPath, $type)    {        switch ($type) {            case 1: // GIF                $img = imagecreatefromgif($imgPath);                break;            case 2: // JPG                $img = imagecreatefromjpeg($imgPath);                break;            case 3: // PNG                $img = imagecreatefrompng($imgPath);                break;            default: //其他类型                Tool::alertBack(‘不支持当前图片类型.‘ . $type);                break;        }        return $img;    }    /**     * 创建一个背景图像     * @param int $width     * @param int $height     * @param int $type     * @return resource     */    private function _CreateImg($width, $height, $type)    {        $img = imagecreatetruecolor($width, $height);        switch ($type) {            case 3: //png                imagecolortransparent($img, 0); //设置背景为透明的                imagealphablending($img, false);                imagesavealpha($img, true);                break;            case 4://gif                imagecolortransparent($img, 0);                break;        }        return $img;    }}