为了防止自己辛苦制作的作品被别人窃取，经常给作品添加水印，以此保证作品的唯一性，那么该怎么给图片添加水印呢，如果作品尺寸过大，该如何处理呢，下面小编给大家详细介绍有关PHP给图片添加水印 压缩 剪切的封装类，需要的朋友可以参考下

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：

1. <?php
2. class Image
3. {
4. private $info;
5. private $image;
6. public $type;
7. public function __construct($src)
8. {
9. $this->info=getimagesize($src);
10. $this->type=image_type_to_extension($this->info['2'],false);
11. $fun="imagecreatefrom{$this->type}";
12. $this->image=$fun($src);
13. }
14. /**
15. * 文字水印
16. * @param [type] $font 字体
17. * @param [type] $content 内容
18. * @param [type] $size 文字大小
19. * @param [type] $col 文字颜色（四元数组）
20. * @param array $location 位置
21. * @param integer $angle 倾斜角度
22. * @return [type]
23. */
24. public function fontMark($font,$content,$size,$col,$location,$angle=0){
25. $col=imagecolorallocatealpha($this->image, $col['0'], $col['1'], $col['2'],$col['3']);
26. imagettftext($this->image, $size, $angle, $location['0'], $location['1'], $col,$font,$content);
27. }
28. /**
29. * 图片水印
30. * @param [type] $imageMark 水印图片地址
31. * @param [type] $dst 水印图片在原图片中的位置
32. * @param [type] $pct 透明度
33. * @return [type]
34. */
35. public function imageMark($imageMark,$dst,$pct){
36. $info2=getimagesize($imageMark);
37. $type=image_type_to_extension($info2['2'],false);
38. $func2="imagecreatefrom".$type;
39. $water=$func2($imageMark);
40. imagecopymerge($this->image, $water, $dst[0], $dst[1], 0, 0, $info2['0'], $info2['1'], $pct);
41. imagedestroy($water);
42. }
43. /**
44. * 压缩图片
45. * @param [type] $thumbSize 压缩图片大小
46. * @return [type] [description]
47. */
48. public function thumb($thumbSize){
49. $imageThumb=imagecreatetruecolor($thumbSize[0], $thumbSize[1]);
50. imagecopyresampled($imageThumb, $this->image, 0, 0, 0, 0, $thumbSize[0], $thumbSize[1], $this->info['0'], $this->info['1']);
51. imagedestroy($this->image);
52. $this->image=$imageThumb;
53. }
54. /**
55. * 裁剪图片
56. * @param [type] $cutSize 裁剪大小
57. * @param [type] $location 裁剪位置
58. * @return [type] [description]
59. */
60. public function cut($cutSize,$location){
61. $imageCut=imagecreatetruecolor($cutSize[0],$cutSize[1]);
62. imagecopyresampled($imageCut, $this->image, 0, 0, $location[0], $location[1],$cutSize[0],$cutSize[1],$cutSize[0],$cutSize[1]);
63. imagedestroy($this->image);
64. $this->image=$imageCut;
65. }
66. /**
67. * 展现图片
68. * @return [type] [description]
69. */
70. public function show(){
71. header("content-type:".$this->info['mime']);
72. $funn="image".$this->type;
73. $funn($this->image);
74. }
75. /**
76. * 保存图片
77. * @param [type] $newname 新图片名
78. * @return [type] [description]
79. */
80. public function save($newname){
81. header("content-type:".$this->info['mime']);
82. $funn="image".$this->type;
83. $funn($this->image,$newname.'.'.$this->type);
84. }
85. public function __destruct(){
86. imagedestroy($this->image);
87. }
88. }
89. ?>

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

1. <?php
2. //修改图片效果
3. $db = mysql_connect('localhost','root','Ctrip07185419') or die('can not connect to database');
4. mysql_select_db('moviesite',$db) or die(mysql_error($db));
5. //上传文件的路径
6. $dir = 'D:\Serious\phpdev\test\images';
7. //设置环境变量
8. putenv('GDFONTPATH='.'C:\Windows\Fonts');
9. $font = "arial";
10. //upload_image.php页面传递过来的参数，如果是上传图片
11. if($_POST['submit'] == 'Upload')
12. {
13. if($_FILES['uploadfile']['error'] != UPLOAD_ERR_OK)
14. {
15. switch($_FILES['uploadfile']['error'])
16. {
17. case UPLOAD_ERR_INI_SIZE:
18. die('The uploaded file exceeds the upload_max_filesize directive');
19. break;
20. case UPLOAD_ERR_FORM_SIZE:
21. die('The upload file exceeds the MAX_FILE_SIZE directive that was specified in the HTML form');
22. break;
23. case UPLOAD_ERR_PARTIAL:
24. die('The uploaded file was only partially uploaded');
25. break;
26. case UPLOAD_ERR_NO_FILE:
27. die('No file was uploaded');
28. break;
29. case UPLOAD_ERR_NO_TMP_DIR:
30. die('The server is missing a temporary folder');
31. break;
32. case UPLOAD_ERR_CANT_WRITE:
33. die('The server fail to write the uploaded file to the disk');
34. break;
35. case UPLOAD_ERR_EXTENSION:
36. die('The upload stopped by extension');
37. break;
38. }
39. }
40. $image_caption = $_POST['caption'];
41. $image_username = $_POST['username'];
42. $image_date = date('Y-m-d');
43. list($width,$height,$type,$attr) = getimagesize($_FILES['uploadfile']['tmp_name']);
44. $error = 'The file you upload is not a supported filetype';
45. switch($type)
46. {
47. case IMAGETYPE_GIF:
48. $image = imagecreatefromgif($_FILES['uploadfile']['tmp_name']) or die($error);
49. break;
50. case IMAGETYPE_JPEG:
51. $image = imagecreatefromjpeg($_FILES['uploadfile']['tmp_name']) or die($error);
52. break;
53. case IMAGETYPE_PNG:
54. $image = imagecreatefrompng($_FILES['uploadfile']['tmp_name']) or die($error);
55. break;
56. default:
57. break;
58. }
59. $query = 'insert into images(image_caption,image_username,image_date) values("'.$image_caption.'" , "'.$image_username.'","'.$image_date.'")';
60. $result = mysql_query($query,$db) or die(mysql_error($db));
61. $last_id = mysql_insert_id();
62. // $imagename = $last_id.'.jpg';
63. // imagejpeg($image,$dir.'/'.$imagename);
64. // imagedestroy($image);
65. $image_id = $last_id;
66. imagejpeg($image , $dir.'/'.$image_id.'.jpg');
67. imagedestroy($image);
68. }
69. else //如果图片已经上传，则从数据库中取图片名字
70. {
71. $query = 'select image_id,image_caption,image_username,image_date from images where image_id'];
72. $result = mysql_query($query,$db) or die(mysql_error($db));
73. extract(mysql_fetch_assoc($result));
74. list($width,$height,$type,$attr) = getimagesize($dir.'/'.$image_id.'.jpg');
75. }
76. //如果是保存图片
77. if($_POST['submit'] == 'Save')
78. {
79. if(isset($_POST['id']) && ctype_digit($_POST['id']) && file_exists($dir.'/'.$_POST['id'].'.jpg'))
80. {
81. $image = imagecreatefromjpeg($dir.'/'.$_POST['id'].'.jpg');
82. }
83. else
84. {
85. die('invalid image specified');
86. }
87. $effect = (isset($_POST['effect'])) ? $_POST['effect'] : -1;
88. switch($effect)
89. {
90. case IMG_FILTER_NEGATE:
91. imagefilter($image , IMG_FILTER_NEGATE); //将图像中所有颜色反转
92. break;
93. case IMG_FILTER_GRAYSCALE:
94. imagefilter($image , IMG_FILTER_GRAYSCALE); //将图像转换为灰度的
95. break;
96. case IMG_FILTER_EMBOSS:
97. imagefilter($image , IMG_FILTER_EMBOSS); //使图像浮雕化
98. break;
99. case IMG_FILTER_GAUSSIAN_BLUR:
100. imagefilter($image , IMG_FILTER_GAUSSIAN_BLUR); //用高斯算法模糊图像
101. break;
102. }
103. if(isset($_POST['emb_caption']))
104. {
105. imagettftext($image , 12 , 0 , 20 , 20 , 0 , $font , $image_caption);
106. }
107. if(isset($_POST['emb_logo']))
108. {
109. //获取水印图片的尺寸并创建水印
110. list($wmk_width , $wmk_height) = getimagesize('images/logo.png');
111. $x = ($width-$wmk_width) / 2;
112. $y = ($height-$wmk_height)/2;
113. $wmk = imagecreatefrompng('images/logo.png');
114. //把水印图片和原图片合并在一起
115. imagecopymerge($image , $wmk , $x , $y , 0 , 0 , $wmk_width , $wmk_height , 20);
116. //清除水印图片
117. imagedestroy($wmk);
118. }
119. imagejpeg($image , $dir.'/'.$_POST['id'].'.jpg' , 100);
120. ?>
121. <html>
122. <head>
123. <title>Here is your pic!</title>
124. </head>
125. <body>
126. <h1>Your image has been saved!</h1>
127. <img src="images/<?php echo $_POST['id'];?>.jpg" alt="" />
128. </body>
129. </html>
130. <?php
131. }
132. else
133. {
134. ?>
135. <html>
136. <head>
137. <title>Here is your pic!</title>
138. </head>
139. <body>
140. <h1>So how does it feel to be famous?</h1>
141. <p>Here is the picture you just uploaded to your servers:</p>
142. <!--<img src="images/<?php echo $imagename;?>" alt="" />-->
143. </body>
144. </html>
145. <?php
146. if($_POST['submit'] == 'Upload')
147. {
148. $imagename = 'images/'.$image_id.'.jpg';
149. }
150. else
151. {
152. $imagename = 'image_effect.php?&e='.$_POST['effect'];
153. if(isset($_POST['emb_caption']))
154. {
155. $imagename .= '&capt='.urlencode($image_caption);
156. }
157. if(isset($_POST['emb_logo']))
158. {
159. $imagename .= '&logo=1';
160. }
161. }
162. ?>
163. <img src="<?php echo $imagename;?>" alt="" />
164. <table>
165. <tr>
166. <td>Image save as:</td>
167. <td><?php $image_id?></td>
168. </tr>
169. <tr>
170. <td>Height:</td>
171. <td><?php echo $height;?></td>
172. </tr>
173. <tr>
174. <td>Widht:</td>
175. <td><?php echo $width;?></td>
176. </tr>
177. <tr>
178. <td>Upload date:</td>
179. <td><?php echo $image_date;?></td>
180. </tr>
181. </table>
182. <p>You may apply a special effect to your image from the list of option below.
183. Note:saving an image with any of the filters applied <em>can be undone</em>
184. </p>
185. <form action="<?php echo $_SERVER['PHP_SELF'];?>" method="post">
186. <div>
187. <input type="hidden" name="id" value="<?php echo $image_id;?>"/>
188. Filter:<select name="effect" >
189. <option value="-1">None</option>
190. <?php
191. echo '<option value="'.IMG_FILTER_GRAYSCALE.'" ';
192. if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_GRAYSCALE)
193. {
194. echo 'selected="selected"';
195. }
196. echo ' >Black and white</option>';
197. echo '<option value="'.IMG_FILTER_GAUSSIAN_BLUR.'"';
198. if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_GAUSSIAN_BLUR)
199. {
200. echo ' selected="selected"';
201. }
202. echo '>Blur</option>';
203. echo '<option value="'.IMG_FILTER_EMBOSS.'"';
204. if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_EMBOSS)
205. {
206. echo 'selected="selected"';
207. }
208. echo '>Emboss</option>';
209. echo '<option value="'.IMG_FILTER_NEGATE.'"';
210. if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_NEGATE)
211. {
212. echo 'selected="selected"';
213. }
214. echo '>Negative</option>';
215. ?>
216. </select><br />
217. <?php
218. echo '<input type="checkbox" name="emb_caption"';
219. if(isset($_POST['emb_caption']))
220. {
221. echo ' checked="checked"';
222. }
223. echo ' />Embed caption in image?';
224. echo '<br />';
225. //添加水印选项
226. echo '<input type="checkbox" name="emb_logo" ';
227. if(isset($_POST['emb_logo']))
228. {
229. echo 'checked="checked"';
230. }
231. echo ' />Embed watermarked logo in image?';
232. ?>
233. <input type="submit" value="Preview" name="submit" /><br /><br />
234. <input type="submit" value="Save" name="submit" />
235. </div>
236. </form>
237. <?php
238. }
239. ?>

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：

1. <?php
2. $dir = 'D:\Serious\phpdev\test\images';
3. //设置环境变量
4. putenv('GDFONTPATH='.'C:\Windows\Fonts');
5. $font = "arial";
6. if(isset($_GET['id']) && ctype_digit($_GET['id']) && file_exists($dir.'/'.$_GET['id'].'.jpg'))
7. {
8. $image = imagecreatefromjpeg($dir.'/'.$_GET['id'].'.jpg');
9. }
10. else
11. {
12. die('invalid image specified');
13. }
14. $effect = (isset($_GET['e'])) ? $_GET['e'] : -1;
15. switch($effect)
16. {
17. case IMG_FILTER_NEGATE:
18. imagefilter($image , IMG_FILTER_NEGATE);
19. break;
20. case IMG_FILTER_GRAYSCALE:
21. imagefilter($image , IMG_FILTER_GRAYSCALE);
22. break;
23. case IMG_FILTER_EMBOSS:
24. imagefilter($image , IMG_FILTER_EMBOSS);
25. break;
26. case IMG_FILTER_GAUSSIAN_BLUR:
27. imagefilter($image , IMG_FILTER_GAUSSIAN_BLUR);
28. break;
29. }
30. if(isset($_GET['capt']))
31. {
32. //echo $_GET['capt'];
33. imagettftext($image, 12, 0, 20, 20, 0, $font, $_GET['capt']);
34. }
35. if(isset($_GET['logo']))
36. {
37. list($widht , $height) = getimagesize($dir.'/'.$_GET['id'].'.jpg');
38. list($wmk_width , $wmk_height) = getimagesize('images/logo.png');
39. $x = ($widht-$wmk_width) / 2;
40. $y = ($height-$wmk_height) / 2;
41. $wmk = imagecreatefrompng('images/logo.png');
42. imagecopymerge($image , $wmk , $x , $y , 0 , 0 , $wmk_width , $wmk_height , 20);
43. imagedestroy($wmk);
44. }
45. header('Content-Type:image/jpeg');
46. imagejpeg($image , '' , 100);
47. ?>

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。