给图片添加水印，其实就是把原来的图片和水印添加在一起，下面小编把最近整理的资料分享给大家。
php对图片文件的操作主要是利用GD库扩展。当我们频繁利用php对图片进行操作时，会自然封装很多函数，否则会写太多重复的代码。当有很多对图片的相关函数的时候，我们可以考虑将这些函数也整理一下，因而就有了封装成类的想法。
操作图片主要历经四个步骤：
第一步：打开图片
第二步：操作图片
第三步：输出图片
第四步：销毁图片
1,3,4三个步骤每次都要写，每次又都差不多。真正需要变通的只有操作图片的这一步骤了。操作图片又往往通过1或多个主要的GD函数来完成。
本文封装类里面的四种方法，文字水印（imagettftext()），图片水印（imagecopymerge()），图片压缩，图片剪切(imagecopyresampled())，其余的常用GD函数便不赘述。
直接上代码：
<?php class Image{ private $info; private $image; public $type; public function __construct($src) { $this->info=getimagesize($src); $this->type=image_type_to_extension($this->info["2"],false); $fun="imagecreatefrom{$this->type}"; $this->image=$fun($src); } /** * 文字水印 * @param [type] $font 字体 * @param [type] $content 内容 * @param [type] $size 文字大小 * @param [type] $col 文字颜色（四元数组） * @param array $location 位置 * @param integer $angle 倾斜角度 * @return [type] */ public function fontMark($font,$content,$size,$col,$location,$angle=0){ $col=imagecolorallocatealpha($this->image, $col["0"], $col["1"], $col["2"],$col["3"]); imagettftext($this->image, $size, $angle, $location["0"], $location["1"], $col,$font,$content); } /** * 图片水印 * @param [type] $imageMark 水印图片地址 * @param [type] $dst 水印图片在原图片中的位置 * @param [type] $pct 透明度 * @return [type] */ public function imageMark($imageMark,$dst,$pct){ $info2=getimagesize($imageMark); $type=image_type_to_extension($info2["2"],false); $func2="imagecreatefrom".$type; $water=$func2($imageMark); imagecopymerge($this->image, $water, $dst[0], $dst[1], 0, 0, $info2["0"], $info2["1"], $pct); imagedestroy($water); } /** * 压缩图片 * @param [type] $thumbSize 压缩图片大小 * @return [type] [description] */ public function thumb($thumbSize){ $imageThumb=imagecreatetruecolor($thumbSize[0], $thumbSize[1]); imagecopyresampled($imageThumb, $this->image, 0, 0, 0, 0, $thumbSize[0], $thumbSize[1], $this->info["0"], $this->info["1"]); imagedestroy($this->image); $this->image=$imageThumb; } /** * 裁剪图片 * @param [type] $cutSize 裁剪大小 * @param [type] $location 裁剪位置 * @return [type] [description] */ public function cut($cutSize,$location){ $imageCut=imagecreatetruecolor($cutSize[0],$cutSize[1]); imagecopyresampled($imageCut, $this->image, 0, 0, $location[0], $location[1],$cutSize[0],$cutSize[1],$cutSize[0],$cutSize[1]); imagedestroy($this->image); $this->image=$imageCut; } /** * 展现图片 * @return [type] [description] */ public function show(){ header("content-type:".$this->info["mime"]); $funn="image".$this->type; $funn($this->image); } /** * 保存图片 * @param [type] $newname 新图片名 * @return [type] [description] */ public function save($newname){ header("content-type:".$this->info["mime"]); $funn="image".$this->type; $funn($this->image,$newname.".".$this->type); } public function __destruct(){ imagedestroy($this->image); } } ?>如果还需要其他操作，只需要再往这个类里面添加就好啦~~
给图片添加水印代码：
先看文件check_image_addwatermark.php代码
<?php //修改图片效果$db = mysql_connect("localhost","root","Ctrip07185419") or die("can not connect to database");mysql_select_db("moviesite",$db) or die(mysql_error($db));//上传文件的路径$dir = "D:Seriousphpdev estimages";//设置环境变量putenv("GDFONTPATH="."C:WindowsFonts");$font = "arial";//upload_image.php页面传递过来的参数，如果是上传图片if($_POST["submit"] == "Upload"){ if($_FILES["uploadfile"]["error"] != UPLOAD_ERR_OK) { switch($_FILES["uploadfile"]["error"]) { case UPLOAD_ERR_INI_SIZE: die("The uploaded file exceeds the upload_max_filesize directive"); break; case UPLOAD_ERR_FORM_SIZE: die("The upload file exceeds the MAX_FILE_SIZE directive that was specified in the HTML form"); break; case UPLOAD_ERR_PARTIAL: die("The uploaded file was only partially uploaded"); break; case UPLOAD_ERR_NO_FILE: die("No file was uploaded"); break; case UPLOAD_ERR_NO_TMP_DIR: die("The server is missing a temporary folder"); break; case UPLOAD_ERR_CANT_WRITE: die("The server fail to write the uploaded file to the disk"); break; case UPLOAD_ERR_EXTENSION: die("The upload stopped by extension"); break; } } $image_caption = $_POST["caption"]; $image_username = $_POST["username"]; $image_date = date("Y-m-d"); list($width,$height,$type,$attr) = getimagesize($_FILES["uploadfile"]["tmp_name"]); $error = "The file you upload is not a supported filetype"; switch($type) { case IMAGETYPE_GIF: $image = imagecreatefromgif($_FILES["uploadfile"]["tmp_name"]) or die($error); break; case IMAGETYPE_JPEG: $image = imagecreatefromjpeg($_FILES["uploadfile"]["tmp_name"]) or die($error); break; case IMAGETYPE_PNG: $image = imagecreatefrompng($_FILES["uploadfile"]["tmp_name"]) or die($error); break; default: break; } $query = "insert into images(image_caption,image_username,image_date) values("".$image_caption."" , "".$image_username."","".$image_date."")"; $result = mysql_query($query,$db) or die(mysql_error($db)); $last_id = mysql_insert_id(); // $imagename = $last_id.".jpg"; // imagejpeg($image,$dir."/".$imagename); // imagedestroy($image); $image_id = $last_id; imagejpeg($image , $dir."/".$image_id.".jpg"); imagedestroy($image);}else //如果图片已经上传，则从数据库中取图片名字{ $query = "select image_id,image_caption,image_username,image_date from images where image_id=".$_POST["id"]; $result = mysql_query($query,$db) or die(mysql_error($db)); extract(mysql_fetch_assoc($result)); list($width,$height,$type,$attr) = getimagesize($dir."/".$image_id.".jpg");}//如果是保存图片if($_POST["submit"] == "Save"){ if(isset($_POST["id"]) && ctype_digit($_POST["id"]) && file_exists($dir."/".$_POST["id"].".jpg")) { $image = imagecreatefromjpeg($dir."/".$_POST["id"].".jpg"); } else { die("invalid image specified"); } $effect = (isset($_POST["effect"])) ? $_POST["effect"] : -1; switch($effect) { case IMG_FILTER_NEGATE: imagefilter($image , IMG_FILTER_NEGATE); //将图像中所有颜色反转 break; case IMG_FILTER_GRAYSCALE: imagefilter($image , IMG_FILTER_GRAYSCALE); //将图像转换为灰度的 break; case IMG_FILTER_EMBOSS: imagefilter($image , IMG_FILTER_EMBOSS); //使图像浮雕化 break; case IMG_FILTER_GAUSSIAN_BLUR: imagefilter($image , IMG_FILTER_GAUSSIAN_BLUR); //用高斯算法模糊图像 break; } if(isset($_POST["emb_caption"])) { imagettftext($image , 12 , 0 , 20 , 20 , 0 , $font , $image_caption); } if(isset($_POST["emb_logo"])) { //获取水印图片的尺寸并创建水印 list($wmk_width , $wmk_height) = getimagesize("images/logo.png"); $x = ($width-$wmk_width) / 2; $y = ($height-$wmk_height)/2; $wmk = imagecreatefrompng("images/logo.png"); //把水印图片和原图片合并在一起 imagecopymerge($image , $wmk , $x , $y , 0 , 0 , $wmk_width , $wmk_height , 20); //清除水印图片 imagedestroy($wmk); } imagejpeg($image , $dir."/".$_POST["id"].".jpg" , 100); ?> <html> <head> <title>Here is your pic!</title> </head> <body> <h1>Your image has been saved!</h1> <img src="images/<?php echo $_POST["id"];?>.jpg" alt="" /> </body> </html><?php }else{?> <html> <head> <title>Here is your pic!</title> </head> <body> <h1>So how does it feel to be famous?</h1> <p>Here is the picture you just uploaded to your servers:</p> <!--<img src="images/<?php echo $imagename;?>" alt="" style="float:left;" />--> </body> </html> <?php if($_POST["submit"] == "Upload") { $imagename = "images/".$image_id.".jpg"; } else { $imagename = "image_effect.php?id=".$image_id."&e=".$_POST["effect"]; if(isset($_POST["emb_caption"])) { $imagename .= "&capt=".urlencode($image_caption); } if(isset($_POST["emb_logo"])) { $imagename .= "&logo=1"; } } ?> <img src="<?php echo $imagename;?>" style="float:left;" alt="" /> <table> <tr> <td>Image save as:</td> <td><?php $image_id?></td> </tr> <tr> <td>Height:</td> <td><?php echo $height;?></td> </tr> <tr> <td>Widht:</td> <td><?php echo $width;?></td> </tr> <tr> <td>Upload date:</td> <td><?php echo $image_date;?></td> </tr> </table> <p>You may apply a special effect to your image from the list of option below. Note:saving an image with any of the filters applied <em>can be undone</em> </p> <form action="<?php echo $_SERVER["PHP_SELF"];?>" method="post"> <div> <input type="hidden" name="id" value="<?php echo $image_id;?>"/> Filter:<select name="effect" id=""> <option value="-1">None</option> <?php echo "<option value="".IMG_FILTER_GRAYSCALE."" "; if(isset($_POST["effect"]) && $_POST["effect"] == IMG_FILTER_GRAYSCALE) { echo "selected="selected""; } echo " >Black and white</option>"; echo "<option value="".IMG_FILTER_GAUSSIAN_BLUR."""; if(isset($_POST["effect"]) && $_POST["effect"] == IMG_FILTER_GAUSSIAN_BLUR) { echo " selected="selected""; } echo ">Blur</option>"; echo "<option value="".IMG_FILTER_EMBOSS."""; if(isset($_POST["effect"]) && $_POST["effect"] == IMG_FILTER_EMBOSS) { echo "selected="selected""; } echo ">Emboss</option>"; echo "<option value="".IMG_FILTER_NEGATE."""; if(isset($_POST["effect"]) && $_POST["effect"] == IMG_FILTER_NEGATE) { echo "selected="selected""; } echo ">Negative</option>"; ?> </select><br /> <?php echo "<input type="checkbox" name="emb_caption""; if(isset($_POST["emb_caption"])) { echo " checked="checked""; } echo " />Embed caption in image?"; echo "<br />"; //添加水印选项 echo "<input type="checkbox" name="emb_logo" "; if(isset($_POST["emb_logo"])) { echo "checked="checked""; } echo " />Embed watermarked logo in image?"; ?> <input type="submit" value="Preview" name="submit" /><br /><br /> <input type="submit" value="Save" name="submit" /> </div> </form><?php }?>这里面主要是添加水印选项，如果选中添加水印则将logo.png作为水印图片和原来的图片合并在一起。
在预览文件中添加了对应的逻辑，代码如下：
<?php $dir = "D:Seriousphpdev estimages";//设置环境变量putenv("GDFONTPATH="."C:WindowsFonts");$font = "arial";if(isset($_GET["id"]) && ctype_digit($_GET["id"]) && file_exists($dir."/".$_GET["id"].".jpg")){ $image = imagecreatefromjpeg($dir."/".$_GET["id"].".jpg");}else{ die("invalid image specified");}$effect = (isset($_GET["e"])) ? $_GET["e"] : -1;switch($effect){ case IMG_FILTER_NEGATE: imagefilter($image , IMG_FILTER_NEGATE); break; case IMG_FILTER_GRAYSCALE: imagefilter($image , IMG_FILTER_GRAYSCALE); break; case IMG_FILTER_EMBOSS: imagefilter($image , IMG_FILTER_EMBOSS); break; case IMG_FILTER_GAUSSIAN_BLUR: imagefilter($image , IMG_FILTER_GAUSSIAN_BLUR); break; }if(isset($_GET["capt"])){ //echo $_GET["capt"]; imagettftext($image, 12, 0, 20, 20, 0, $font, $_GET["capt"]);}if(isset($_GET["logo"])){ list($widht , $height) = getimagesize($dir."/".$_GET["id"].".jpg"); list($wmk_width , $wmk_height) = getimagesize("images/logo.png"); $x = ($widht-$wmk_width) / 2; $y = ($height-$wmk_height) / 2; $wmk = imagecreatefrompng("images/logo.png"); imagecopymerge($image , $wmk , $x , $y , 0 , 0 , $wmk_width , $wmk_height , 20); imagedestroy($wmk);}header("Content-Type:image/jpeg");imagejpeg($image , "" , 100);?>最后上传的水印图片效果如下：
注意主要的逻辑就是通过 imagecopymerge() 方法把两个图片合并在一起造成水印效果。来看看这个方法的方法原型和参数：
bool imagecopymerge ( resource $dst_im , resource $src_im , int $dst_x , int $dst_y , int$src_x , int $src_y , int $src_w , int $src_h , int $pct )
将 src_im 图像中坐标从 src_x，src_y 开始，宽度为 src_w，高度为 src_h 的一部分拷贝到 dst_im 图像中坐标为 dst_x 和 dst_y 的位置上。两图像将根据 pct 来决定合并程度，其值范围从 0 到 100。当 pct = 0 时，实际上什么也没做，当为 100 时对于调色板图像本函数和 imagecopy() 完全一样，它对真彩色图像实现了 alpha 透明。
以上内容是本文介绍PHP给图片添加水印 压缩 剪切的封装类的全部内容，希望大家对本文介绍感兴趣。
