一个PHP智能把图片生成缩略图类,可自动根据你图片的大小生成等比例的图片,PHP智能把图片生成缩略图类代码如下:

1. <?php
2. /*************************************** *作者：落梦天蝎（beluckly）
3. *开源代码phpfensi.com
4. *类名：CreatMiniature
5. *功能：生成多种类型的缩略图
6. *基本参数：$srcFile,$echoType
7. *方法用到的参数：
8. $toFile,生成的文件
9. $toW,生成的宽
10. $toH,生成的高
11. $bk1,背景颜色参数 以255为最高
12. $bk2,背景颜色参数
13. $bk3,背景颜色参数
14. *例子：
15. include("thumb.php");
16. $cm=new CreatMiniature();
17. $cm->SetVar("1.jpg","file");
18. $cm->Distortion("dis_bei.jpg",150,200);
19. $cm->Prorate("pro_bei.jpg",150,200);
20. $cm->Cut("cut_bei.jpg",150,200);
21. $cm->BackFill("fill_bei.jpg",150,200);
22. ***************************************/
23. class CreatMiniature
24. {
25. //公共变量
26. var $srcFile=""; //原图
27. var $echoType; //输出图片类型，link--不保存为文件；file--保存为文件
28. var $im=""; //临时变量
29. var $srcW=""; //原图宽
30. var $srcH=""; //原图高
31. //设置变量及初始化
32. function SetVar($srcFile,$echoType)
33. {
34. $this->srcFile=$srcFile;
35. $this->echoType=$echoType;
36. $info = "";
37. $data = GetImageSize($this->srcFile,$info);
38. switch ($data[2]) {
39. case 1:
40. if(!function_exists("imagecreatefromgif")){
41. echo "你的GD库不能使用GIF格式的图片，请使用Jpeg或PNG格式！<a href='javascript：go(-1);'>返回</a>";
42. exit();
43. }
44. $this->im = ImageCreateFromGIF($this->srcFile);
45. break;
46. case 2:
47. if(!function_exists("imagecreatefromjpeg")){
48. echo "你的GD库不能使用jpeg格式的图片，请使用其它格式的图片！<a href='javascript：go(-1);'>返回</a>";
49. exit();
50. }
51. $this->im = ImageCreateFromJpeg($this->srcFile);
52. break;
53. case 3:
54. $this->im = ImageCreateFromPNG($this->srcFile);
55. break;
56. }
57. $this->srcW=ImageSX($this->im);
58. $this->srcH=ImageSY($this->im);
59. }
60. //生成扭曲型缩图
61. function Distortion($toFile,$toW,$toH)
62. {
63. $cImg=$this->CreatImage($this->im,$toW,$toH,0,0,0,0,$this->srcW,$this->srcH);
64. return $this->EchoImage($cImg,$toFile);
65. ImageDestroy($cImg);
66. }
67. //生成按比例缩放的缩图
68. function Prorate($toFile,$toW,$toH)
69. {
70. $toWH=$toW/$toH;
71. $srcWH=$this->srcW/$this->srcH;
72. if($toWH< =$srcWH)
73. {
74. $ftoW=$toW;
75. $ftoH=$ftoW*($this->srcH/$this->srcW);
76. }
77. else {
78. $ftoH=$toH;
79. $ftoW=$ftoH*($this->srcW/$this->srcH);
80. }
81. if($this->srcW>$toW||$this->srcH>$toH)
82. {
83. $cImg=$this->CreatImage($this->im,$ftoW,$ftoH,0,0,0,0,$this->srcW,$this->srcH);
84. return $this->EchoImage($cImg,$toFile);
85. ImageDestroy($cImg);
86. }
87. else
88. {
89. $cImg=$this->CreatImage($this->im,$this->srcW,$this->srcH,0,0,0,0,$this->srcW,$this->srcH);
90. return $this->EchoImage($cImg,$toFile);
91. ImageDestroy($cImg);
92. }
93. }
94. //生成最小裁剪后的缩图
95. function Cut($toFile,$toW,$toH)
96. {
97. $toWH=$toW/$toH;
98. $srcWH=$this->srcW/$this->srcH;
99. if($toWH< =$srcWH)
100. {
101. $ctoH=$toH;
102. $ctoW=$ctoH*($this->srcW/$this->srcH);
103. }
104. else
105. {
106. $ctoW=$toW;
107. $ctoH=$ctoW*($this->srcH/$this->srcW);
108. }
109. $allImg=$this->CreatImage($this->im,$ctoW,$ctoH,0,0,0,0,$this->srcW,$this->srcH);
110. $cImg=$this->CreatImage($allImg,$toW,$toH,0,0,($ctoW-$toW)/2,($ctoH-$toH)/2,$toW,$toH);
111. return $this->EchoImage($cImg,$toFile);
112. ImageDestroy($cImg);
113. ImageDestroy($allImg);
114. }
115. //生成背景填充的缩图
116. function BackFill($toFile,$toW,$toH,$bk1=255,$bk2=255,$bk3=255)
117. {
118. $toWH=$toW/$toH;
119. $srcWH=$this->srcW/$this->srcH;
120. if($toWH< =$srcWH)
121. {
122. $ftoW=$toW;
123. $ftoH=$ftoW*($this->srcH/$this->srcW);
124. }
125. else
126. {
127. $ftoH=$toH;
128. $ftoW=$ftoH*($this->srcW/$this->srcH);
129. }
130. if(function_exists("imagecreatetruecolor"))
131. {
132. @$cImg=ImageCreateTrueColor($toW,$toH);
133. if(!$cImg)
134. {
135. $cImg=ImageCreate($toW,$toH);
136. }
137. }
138. else
139. {
140. $cImg=ImageCreate($toW,$toH);
141. }
142. $backcolor = imagecolorallocate($cImg, $bk1, $bk2, $bk3); //填充的背景颜色
143. ImageFilledRectangle($cImg,0,0,$toW,$toH,$backcolor);
144. if($this->srcW>$toW||$this->srcH>$toH)
145. {
146. $proImg=$this->CreatImage($this->im,$ftoW,$ftoH,0,0,0,0,$this->srcW,$this->srcH);
147. /*
148. if($ftoW< $toW)
149. {
150. ImageCopyMerge($cImg,$proImg,($toW-$ftoW)/2,0,0,0,$ftoW,$ftoH,100);
151. }
152. else if($ftoH<$toH)
153. {
154. ImageCopyMerge($cImg,$proImg,0,($toH-$ftoH)/2,0,0,$ftoW,$ftoH,100);
155. }
156. */
157. if($ftoW<$toW)
158. {
159. ImageCopy($cImg,$proImg,($toW-$ftoW)/2,0,0,0,$ftoW,$ftoH);
160. }
161. else if($ftoH<$toH)
162. {
163. ImageCopy($cImg,$proImg,0,($toH-$ftoH)/2,0,0,$ftoW,$ftoH);
164. }
165. else
166. {
167. ImageCopy($cImg,$proImg,0,0,0,0,$ftoW,$ftoH);
168. }
169. }
170. else
171. {
172. ImageCopyMerge($cImg,$this->im,($toW-$ftoW)/2,($toH-$ftoH)/2,0,0,$ftoW,$ftoH,100);
173. }
174. return $this->EchoImage($cImg,$toFile);
175. ImageDestroy($cImg);
176. }
177. function CreatImage($img,$creatW,$creatH,$dstX,$dstY,$srcX,$srcY,$srcImgW,$srcImgH)
178. {
179. if(function_exists("imagecreatetruecolor"))
180. {
181. @$creatImg = ImageCreateTrueColor($creatW,$creatH); if($creatImg)
182. ImageCopyResampled($creatImg,$img,$dstX,$dstY,$srcX,$srcY,$creatW,$creatH,$srcImgW,$srcImgH);
183. else
184. {
185. $creatImg=ImageCreate($creatW,$creatH);
186. ImageCopyResized($creatImg,$img,$dstX,$dstY,$srcX,$srcY,$creatW,$creatH,$srcImgW,$srcImgH);
187. }
188. }
189. else
190. {
191. $creatImg=ImageCreate($creatW,$creatH);
192. ImageCopyResized($creatImg,$img,$dstX,$dstY,$srcX,$srcY,$creatW,$creatH,$srcImgW,$srcImgH);
193. }
194. return $creatImg;
195. }
196. //输出图片，link---只输出，不保存文件。file--保存为文件
197. function EchoImage($img,$to_File)
198. {
199. switch($this->echoType) {
200. case "link":
201. if(function_exists('imagejpeg')) return ImageJpeg($img);
202. else return ImagePNG($img);
203. break;
204. case "file":
205. if(function_exists('imagejpeg')) return ImageJpeg($img,$to_File);
206. else return ImagePNG($img,$to_File);
207. break;
208. }
209. }
210. }
211. ?>