今天小编就为大家分享一篇关于PHP添加文字水印或图片水印的水印类完整源代码与使用示例，小编觉得内容挺不错的，现在分享给大家，具有很好的参考价值，需要的朋友一起跟随小编来看看吧。

PHP实现的给图片添加水印功能，可添加文字水印或图片水印，使用文字水印时需要提供字体文件，使用图片水印时需要提供水印图片，水印图片不能比要添加水印的图片大，请使用背景透明的水印图片。

该水印类支持自定义水印位置、自定义水印大小和水印的透明度，字体水印可自定义颜色等，功能已相应完善。

完整源代码如下(注解中已给出使用示例)：

1. <?php
2. /**
3. * 图片加水印类，支持文字水印、透明度设置、自定义水印位置等。
4. * 使用示例：
5. * $obj = new WaterMask($imgFileName); //实例化对象
6. * $obj->$waterType = 1; //类型：0为文字水印、1为图片水印
7. * $obj->$transparent = 45; //水印透明度
8. * $obj->$waterStr = 'www.jb51.net'; //水印文字
9. * $obj->$fontSize = 18; //文字字体大小
10. * $obj->$fontColor = array(255,255,255); //水印文字颜色（RGB）
11. * $obj->$fontFile = 'AHGBold.ttf'; //字体文件
12. * ……
13. * $obj->output(); //输出水印图片文件覆盖到输入的图片文件
14. */
15. class WaterMask{
16. public $waterType = 0; //水印类型：0为文字水印、1为图片水印
17. public $pos = 0; //水印位置
18. public $transparent = 45; //水印透明度
19. public $waterStr = 'www.jb51.net'; //水印文字
20. public $fontSize = 18; //文字字体大小
21. public $fontColor = array(255,255,255); //水印文字颜色（RGB）
22. public $fontFile = 'AHGBold.ttf'; //字体文件
23. public $waterImg = 'logo.png'; //水印图片
24. private $srcImg = ''; //需要添加水印的图片
25. private $im = ''; //图片句柄
26. private $water_im = ''; //水印图片句柄
27. private $srcImg_info = ''; //图片信息
28. private $waterImg_info = ''; //水印图片信息
29. private $str_w = ''; //水印文字宽度
30. private $str_h = ''; //水印文字高度
31. private $x = ''; //水印X坐标
32. private $y = ''; //水印y坐标
33. function __construct($img) { //析构函数
34. $this->srcImg = file_exists($img) ? $img : die('"'.$img.'" 源文件不存在！');
35. }
36. private function imginfo() { //获取需要添加水印的图片的信息，并载入图片。
37. $this->srcImg_info = getimagesize($this->srcImg);
38. switch ($this->srcImg_info[2]) {
39. case 3:
40. $this->im = imagecreatefrompng($this->srcImg);
41. break 1;
42. case 2:
43. $this->im = imagecreatefromjpeg($this->srcImg);
44. break 1;
45. case 1:
46. $this->im = imagecreatefromgif($this->srcImg);
47. break 1;
48. default:
49. die('原图片（'.$this->srcImg.'）格式不对，只支持PNG、JPEG、GIF。');
50. }
51. }
52. private function waterimginfo() { //获取水印图片的信息，并载入图片。
53. $this->waterImg_info = getimagesize($this->waterImg);
54. switch ($this->waterImg_info[2]) {
55. case 3:
56. $this->water_im = imagecreatefrompng($this->waterImg);
57. break 1;
58. case 2:
59. $this->water_im = imagecreatefromjpeg($this->waterImg);
60. break 1;
61. case 1:
62. $this->water_im = imagecreatefromgif($this->waterImg);
63. break 1;
64. default:
65. die('水印图片（'.$this->srcImg.'）格式不对，只支持PNG、JPEG、GIF。');
66. }
67. }
68. private function waterpos() { //水印位置算法
69. switch ($this->pos) {
70. case 0: //随机位置
71. $this->x = rand(0,$this->srcImg_info[0]-$this->waterImg_info[0]);
72. $this->y = rand(0,$this->srcImg_info[1]-$this->waterImg_info[1]);
73. break 1;
74. case 1: //上左
75. $this->x = 0;
76. $this->y = 0;
77. break 1;
78. case 2: //上中
79. $this->x = ($this->srcImg_info[0]-$this->waterImg_info[0])/2;
80. $this->y = 0;
81. break 1;
82. case 3: //上右
83. $this->x = $this->srcImg_info[0]-$this->waterImg_info[0];
84. $this->y = 0;
85. break 1;
86. case 4: //中左
87. $this->x = 0;
88. $this->y = ($this->srcImg_info[1]-$this->waterImg_info[1])/2;
89. break 1;
90. case 5: //中中
91. $this->x = ($this->srcImg_info[0]-$this->waterImg_info[0])/2;
92. $this->y = ($this->srcImg_info[1]-$this->waterImg_info[1])/2;
93. break 1;
94. case 6: //中右
95. $this->x = $this->srcImg_info[0]-$this->waterImg_info[0];
96. $this->y = ($this->srcImg_info[1]-$this->waterImg_info[1])/2;
97. break 1;
98. case 7: //下左
99. $this->x = 0;
100. $this->y = $this->srcImg_info[1]-$this->waterImg_info[1];
101. break 1;
102. case 8: //下中
103. $this->x = ($this->srcImg_info[0]-$this->waterImg_info[0])/2;
104. $this->y = $this->srcImg_info[1]-$this->waterImg_info[1];
105. break 1;
106. default: //下右
107. $this->x = $this->srcImg_info[0]-$this->waterImg_info[0];
108. $this->y = $this->srcImg_info[1]-$this->waterImg_info[1];
109. break 1;
110. }
111. }
112. private function waterimg() {
113. if ($this->srcImg_info[0] <= $this->waterImg_info[0] || $this->srcImg_info[1] <= $this->waterImg_info[1]){
114. die('水印比原图大！');
115. }
116. $this->waterpos();
117. $cut = imagecreatetruecolor($this->waterImg_info[0],$this->waterImg_info[1]);
118. imagecopy($cut,$this->im,0,0,$this->x,$this->y,$this->waterImg_info[0],$this->waterImg_info[1]);
119. $pct = $this->transparent;
120. imagecopy($cut,$this->water_im,0,0,0,0,$this->waterImg_info[0],$this->waterImg_info[1]);
121. imagecopymerge($this->im,$cut,$this->x,$this->y,0,0,$this->waterImg_info[0],$this->waterImg_info[1],$pct);
122. }
123. private function waterstr() {
124. $rect = imagettfbbox($this->fontSize,0,$this->fontFile,$this->waterStr);
125. $w = abs($rect[2]-$rect[6]);
126. $h = abs($rect[3]-$rect[7]);
127. $fontHeight = $this->fontSize;
128. $this->water_im = imagecreatetruecolor($w, $h);
129. imagealphablending($this->water_im,false);
130. imagesavealpha($this->water_im,true);
131. $white_alpha = imagecolorallocatealpha($this->water_im,255,255,255,127);
132. imagefill($this->water_im,0,0,$white_alpha);
133. $color = imagecolorallocate($this->water_im,$this->fontColor[0],$this->fontColor[1],$this->fontColor[2]);
134. imagettftext($this->water_im,$this->fontSize,0,0,$this->fontSize,$color,$this->fontFile,$this->waterStr);
135. $this->waterImg_info = array(0=>$w,1=>$h);
136. $this->waterimg();
137. }
138. function output() {
139. $this->imginfo();
140. if ($this->waterType == 0) {
141. $this->waterstr();
142. }else {
143. $this->waterimginfo();
144. $this->waterimg();
145. }
146. switch ($this->srcImg_info[2]) {
147. case 3:
148. imagepng($this->im,$this->srcImg);
149. break 1;
150. case 2:
151. imagejpeg($this->im,$this->srcImg);
152. break 1;
153. case 1:
154. imagegif($this->im,$this->srcImg);
155. break 1;
156. default:
157. die('添加水印失败！');
158. break;
159. }
160. imagedestroy($this->im);
161. imagedestroy($this->water_im);
162. }
163. }
164. ?>