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:Seriousphpdevtestimages';
//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:Seriousphpdevtestimages';
//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：
Notice: Undefined index: CMSdown in /data/webroot/gcms/lib/Api/Open/Article.php on line 161
img/2015/08/19/115759_55d3fec790ad0.png" alt="查看图片" />
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。