php图片水印类详解编程语言

<?php 
class Image { 
    private $path; 
    //构造方法用来对图片所在位置进行初使化 
    function __construct($path="./"){ 
        $this->path=rtrim($path, "/")."/"; 
        $this -> path = ''; 
    } 
    /* 对图片进行缩放 
     * 
     * 参数$name: 是需要处理的图片名称 
     * 参数$width:是缩放后的宽度 
     * 参数$height:是缩放后的高度 
     * 参数$qz: 是新图片的名称前缀 
     * 返回值:就是缩放后的图片名称，失败则返回false 
     * 
     */ 
    function thumb($name, $width, $height, $qz="th_"){ 
        //获取图片信息 
        $imgInfo=$this->getInfo($name); //图片的宽度，高度，类型 
        //获取图片资源, 各种类型的图片都可以创建资源 jpg, gif, png 
        $srcImg=$this->getImg($name, $imgInfo); 
        //获取计算图片等比例之后的大小, $size["width"], $size["height"] 
        $size=$this->getNewSize($name, $width, $height, $imgInfo); 
        //获取新的图片资源, 处理一下gif透明背景 
        $newImg=$this->kidOfImage($srcImg, $size, $imgInfo); 
        //另存为一个新的图片，返回新的缩放后的图片名称     
        return $this->createNewImage($newImg, $qz.$name, $imgInfo);     
    } 
 
    private function createNewImage($newImg, $newName, $imgInfo){ 
        switch($imgInfo["type"]){ 
        case 1://gif 
            Header("Content-type: image/gif"); 
            $result=imageGif($newImg); 
            break; 
        case 2://jpg 
            Header("Content-type: image/jpg"); 
            $result=imageJPEG($newImg); 
            break; 
        case 3://png 
            Header("Content-type: image/png"); 
            $return=imagepng($newImg); 
            break; 
        } 
        imagedestroy($newImg); 
        return $newName; 
    } 
 
    private function kidOfImage($srcImg, $size, $imgInfo){ 
        $newImg=imagecreatetruecolor($size["width"], $size["height"]); 
 
        $otsc=imagecolortransparent($srcImg); 
 
        if($otsc >=0 && $otsc <= imagecolorstotal($srcImg)){ 
            $tran=imagecolorsforindex($srcImg, $otsc); 
 
            $newt=imagecolorallocate($newImg, $tran["red"], $tran["green"], $tran["blue"]); 
 
            imagefill($newImg, 0, 0, $newt); 
 
            imagecolortransparent($newImg, $newt); 
        } 
 
        imagecopyresized($newImg, $srcImg, 0, 0, 0, 0, $size["width"], $size["height"], $imgInfo["width"], $imgInfo["height"]); 
 
        imagedestroy($srcImg); 
 
        return $newImg; 
    } 
 
    private function getNewSize($name, $width, $height, $imgInfo){ 
        $size["width"]=$imgInfo["width"]; 
        $size["height"]=$imgInfo["height"]; 
 
        //缩放的宽度如果比原图小才重新设置宽度 
        if($width < $imgInfo["width"]){ 
            $size["width"]=$width; 
        } 
        //缩放的高度如果比原图小才重新设置高度 
        if($height < $imgInfo["height"]){ 
            $size["height"]=$height; 
        } 
 
        //图片等比例缩放的算法 
        if($imgInfo["width"]*$size["width"] > $imgInfo["height"] * $size["height"]){ 
            $size["height"]=round($imgInfo["height"]*$size["width"]/$imgInfo["width"]); 
        }else{ 
            $size["width"]=round($imgInfo["width"]*$size["height"]/$imgInfo["height"]); 
        } 
 
 
        return $size; 
 
    } 
 
    public function getInfo($name){ 
        $data=getImageSize($this->path.$name); 
 
        $imageInfo["width"]=$data[0]; 
        $imageInfo["height"]=$data[1]; 
        $imageInfo["type"]=$data[2]; 
 
        return $imageInfo; 
    } 
 
    private function getImg($name, $imgInfo){ 
        $srcPic=$this->path.$name; 
 
        switch($imgInfo["type"]){ 
        case 1: //gif 
            $img=imagecreatefromgif($srcPic); 
            break; 
        case 2: //jpg 
            $img=imageCreatefromjpeg($srcPic); 
            break; 
        case 3: //png 
            $img=imageCreatefrompng($srcPic); 
            break; 
        default: 
            return false; 
 
        } 
 
        return $img; 
    } 
    /* 功能：为图片加水印图片 
     * 参数$groundName: 背景图片，即需要加水印的图片 
     * 参数$waterName: 水钱图片 
     * 参数#aterPost：水印位置， 10种状态，  
     *  0为随机位置 
     * 
     *  1. 为顶端居左  2. 为顶端居中  3 为顶端居右 
     *  4  为中部居左  5. 为中部居中  6 为中部居右 
     *  7 . 为底端居左 8. 为底端居中， 9. 为底端居右 
     * 
     * 参数$qz : 是加水印后的图片名称前缀 
     * 返回值：就是处理后图片的名称 
     * 
     */ 
    function waterMark($groundName, $waterName, $waterPos=0, $qz="wa_"){ 
 
 
        $groundInfo=$this->getInfo($groundName); 
        $waterInfo=$this->getInfo($waterName); 
        //水印的位置 
        if(!$pos=$this->position($groundInfo, $waterInfo, $waterPos)){ 
            return "Picture too small!"; 
        } 
 
        $groundImg=$this->getImg($groundName, $groundInfo); 
        $waterImg=$this->getImg($waterName, $waterInfo); 
 
        $groundImg=$this->copyImage($groundImg, $waterImg, $pos, $waterInfo); 
 
        return $this->createNewImage($groundImg, $qz.$groundName, $groundInfo); 
 
    } 
 
    private function copyImage($groundImg, $waterImg, $pos, $waterInfo){ 
        imagecopy($groundImg, $waterImg, $pos["posX"], $pos["posY"], 0, 0, $waterInfo["width"], $waterInfo["height"]); 
        imagedestroy($waterImg); 
 
        return $groundImg; 
    } 
 
    private function position($groundInfo, $waterInfo, $waterPos){ 
        //需要背景比水印图片大 
        if(($groundInfo["width"]< $waterInfo["width"]) ||($groundInfo["height"] < $waterInfo["height"])){ 
            return false; 
        } 
 
        switch($waterPos){ 
        case 1: 
            $posX=0; 
            $posY=0; 
            break; 
        case 2: 
            $posX=($groundInfo["width"]-$waterInfo["width"])/2; 
            $posY=0; 
            break; 
        case 3: 
            $posX=$groundInfo["width"]-$waterInfo["width"]; 
            $posY=0; 
            break; 
        case 4: 
            $posX=0; 
            $posY=($groundInfo["height"]-$waterInfo["height"]) /2; 
            break; 
        case 5: 
            $posX=($groundInfo["width"]-$waterInfo["width"])/2; 
            $posY=($groundInfo["height"]-$waterInfo["height"]) /2; 
            break; 
        case 6: 
            $posX=$groundInfo["width"]-$waterInfo["width"]; 
            $posY=($groundInfo["height"]-$waterInfo["height"]) /2; 
            break; 
        case 7: 
            $posX=0; 
            $posY=$groundInfo["height"]-$waterInfo["height"]; 
            break; 
        case 8: 
            $posX=($groundInfo["width"]-$waterInfo["width"])/2; 
            $posY=$groundInfo["height"]-$waterInfo["height"]; 
            break; 
        case 9: 
            $posX=$groundInfo["width"]-$waterInfo["width"]; 
            $posY=$groundInfo["height"]-$waterInfo["height"]; 
            break; 
        case 0: 
        default: 
        $posX=rand(0, ($groundInfo["width"]-$waterInfo["width"])); 
        $posY=rand(0, ($groundInfo["height"]-$waterInfo["height"])); 
        break; 
        } 
 
        return array("posX"=>$posX, "posY"=>$posY); 
    } 
 
}