`1. //-----------ImageCheck.class.php------------------
2. <?
3. /*
4. php缩略图函数：
5. 等比例无损压缩，可填充补充色
6. 主持格式：bmp 、jpg 、gif、png
7. param:
8. @srcimage : 要缩小的图片
9. @dstimage : 要保存的图片
10. @dst_width: 缩小宽
11. @dst_height: 缩小高
12. @backgroundcolor: 补充色 如：#FFFFFF 支持 6位 不支持3位
13. */
14. class ImageCheck{
15. public function imagezoom($srcimage,$dstimage,$dst_width,$dst_height,$backgroundcolor ){
16. // 中文件名乱码
17. if ( PHP_OS == 'WINNT' ) {
18. $srcimage = iconv('UTF-8','GBK',$srcimage);
19. $dstimage = iconv('UTF-8','GBK',$dstimage);
20. }
21. $dstimg = imagecreatetruecolor( $dst_width, $dst_height );
22. $color = imagecolorallocate($dstimg,hexdec(substr($backgroundcolor, 1, 2)),hexdec(substr($backgroundcolor, 3, 2)),hexdec(substr($backgroundcolor, 5, 2)));
23. //echo $srcimage;
24. imagefill($dstimg, 0, 0, $color);
25. //dump(getimagesize($srcimage));
26. if ( !$arr=getimagesize($srcimage) ) {
27. echo "要生成缩略图的文件不存在";
28. exit;
29. }
30. $src_width = $arr[0];
31. $src_height = $arr[1];
32. $srcimg =null;
33. $method =$this->getcreatemethod($srcimage);
34. if ( $method ) {
35. eval( '$srcimg ='.$method.';');
36. }
37. $dst_x = 0;
38. $dst_y = 0;
39. $dst_w = $dst_width;
40. $dst_h = $dst_height;
41. if ( ($dst_width / $dst_height - $src_width / $src_height) > 0 ) {
42. $dst_w = $src_width * ( $dst_height / $src_height );
43. $dst_x = ( $dst_width - $dst_w ) / 2;
44. } elseif ( ($dst_width / $dst_height - $src_width / $src_height) < 0 ) {
45. $dst_h = $src_height * ( $dst_width / $src_width );
46. $dst_y = ( $dst_height - $dst_h ) / 2;
47. }
48. imagecopyresampled($dstimg,$srcimg,$dst_x,$dst_y,0,0,$dst_w,$dst_h,$src_width,$src_height);
49. // 保存格式
50. $arr = array(
51. 'jpg' => 'imagejpeg',
52. 'jpeg' => 'imagejpeg',
53. 'png' => 'imagepng',
54. 'gif' => 'imagegif',
55. 'bmp' => 'imagebmp'
56. );
57. $suffix = strtolower(array_pop(explode('.', $dstimage ) ) );
58. if (!in_array($suffix,array_keys($arr))) {
59. echo "保存的文件名错误";
60. exit;
61. } else {
62. eval( $arr[$suffix] . '($dstimg, "'.$dstimage.'");' );
63. }
64. imagejpeg($dstimg,$dstimage);
65. imagedestroy($dstimg);
66. imagedestroy($srcimg);
67. }
68. //*************************************************************
69. public function getcreatemethod($file){
70. $arr = array(
71. '474946' => "imagecreatefromgif('$file')",
72. 'FFD8FF' => "imagecreatefromjpeg('$file')",
73. '424D' => "imagecreatefrombmp('$file')",
74. '89504E' => "imagecreatefrompng('$file')"
75. );
76. $fd = fopen( $file, "rb" );
77. $data = fread( $fd, 3 );
78. $data =$this->str2hex( $data );
79. if( array_key_exists( $data, $arr ) ) {
80. return $arr[$data];
81. }else if( array_key_exists( substr($data, 0, 4), $arr ) ) {
82. return $arr[substr($data, 0, 4)];
83. }else{
84. return false;
85. }
86. }
87. //**********************************************************
88. public function str2hex( $str ) {
89. $ret = "";
90. for( $i = 0; $i < strlen( $str ) ; $i++ ) {
91. $ret .= ord($str[$i]) >= 16 ? strval( dechex( ord($str[$i]) ) ):'0'.strval( dechex( ord($str[$i]) ) );
92. }
93. return strtoupper( $ret );
94. }
95. //***********************************************************
96. public function imagecreatefrombmp($filename){
97. if (! $f1 = fopen($filename,"rb")) return FALSE;
98. $FILE = unpack("vfile_type/Vfile_size/Vreserved/Vbitmap_offset", fread($f1,14));
99. if ($FILE['file_type'] != 19778) return FALSE;
100. $BMP = unpack('Vheader_size/Vwidth/Vheight/vplanes/vbits_per_pixel'.'/Vcompression/Vsize_bitmap/Vhoriz_resolution'.'/Vvert_resolution/Vcolors_used/Vcolors_important', fread($f1,40));
101. $BMP['colors'] = pow(2,$BMP['bits_per_pixel']);
102. if ($BMP['size_bitmap'] == 0) $BMP['size_bitmap'] = $FILE['file_size'] - $FILE['bitmap_offset'];
103. $BMP['bytes_per_pixel'] = $BMP['bits_per_pixel']/8;
104. $BMP['bytes_per_pixel2'] = ceil($BMP['bytes_per_pixel']);
105. $BMP['decal'] = ($BMP['width']*$BMP['bytes_per_pixel']/4);
106. $BMP['decal'] -= floor($BMP['width']*$BMP['bytes_per_pixel']/4);
107. $BMP['decal'] = 4-(4*$BMP['decal']);
108. if ($BMP['decal'] == 4) $BMP['decal'] = 0;
109. $PALETTE = array();
110. if ($BMP['colors'] < 16777216)
111. {
112. $PALETTE = unpack('V'.$BMP['colors'], fread($f1,$BMP['colors']*4));
113. }
114. $IMG = fread($f1,$BMP['size_bitmap']);
115. $VIDE = chr(0);
116. $res = imagecreatetruecolor($BMP['width'],$BMP['height']);
117. $P = 0;
118. $Y = $BMP['height']-1;
119. while ($Y >= 0)
120. {
121. $X=0;
122. while ($X < $BMP['width'])
123. {
124. if ($BMP['bits_per_pixel'] == 24)
125. $COLOR = unpack("V",substr($IMG,$P,3).$VIDE);
126. else if ($BMP['bits_per_pixel'] == 16){
127. $COLOR = unpack("n",substr($IMG,$P,2));
128. $COLOR[1] = $PALETTE[$COLOR[1]+1];
129. }else if ($BMP['bits_per_pixel'] == 8){
130. $COLOR = unpack("n",$VIDE.substr($IMG,$P,1));
131. $COLOR[1] = $PALETTE[$COLOR[1]+1];
132. }else if ($BMP['bits_per_pixel'] == 4){
133. $COLOR = unpack("n",$VIDE.substr($IMG,floor($P),1));
134. if (($P*2)%2 == 0) $COLOR[1] = ($COLOR[1] >> 4) ; else $COLOR[1] = ($COLOR[1] & 0x0F);
135. $COLOR[1] = $PALETTE[$COLOR[1]+1];
136. }else if ($BMP['bits_per_pixel'] == 1){
137. $COLOR = unpack("n",$VIDE.substr($IMG,floor($P),1));
138. if (($P*8)%8 == 0) $COLOR[1] = $COLOR[1] >>7;
139. elseif (($P*8)%8 == 1) $COLOR[1] = ($COLOR[1] & 0x40)>>6;
140. elseif (($P*8)%8 == 2) $COLOR[1] = ($COLOR[1] & 0x20)>>5;
141. elseif (($P*8)%8 == 3) $COLOR[1] = ($COLOR[1] & 0x10)>>4;
142. elseif (($P*8)%8 == 4) $COLOR[1] = ($COLOR[1] & 0x8)>>3;
143. elseif (($P*8)%8 == 5) $COLOR[1] = ($COLOR[1] & 0x4)>>2;
144. elseif (($P*8)%8 == 6) $COLOR[1] = ($COLOR[1] & 0x2)>>1;
145. elseif (($P*8)%8 == 7) $COLOR[1] = ($COLOR[1] & 0x1);
146. $COLOR[1] = $PALETTE[$COLOR[1]+1];
147. }else
148. return FALSE;
149. imagesetpixel($res,$X,$Y,$COLOR[1]);
150. $X++;
151. $P += $BMP['bytes_per_pixel'];
152. }
153. $Y--;
154. $P+=$BMP['decal'];
155. }
156. fclose($f1);
157. return $res;
158. }
159. //*********************************BMP保存函数*************************************************
160. public function imagebmp ($im, $fn = false){
161. if (!$im) return false;
162. if ($fn === false) $fn = 'php://output';
163. $f = fopen ($fn, "w");
164. if (!$f) return false;
165. $biWidth = imagesx ($im);
166. $biHeight = imagesy ($im);
167. $biBPLine = $biWidth * 3;
168. $biStride = ($biBPLine + 3) & ~3;
169. $biSizeImage = $biStride * $biHeight;
170. $bfOffBits = 54;
171. $bfSize = $bfOffBits + $biSizeImage;
172. fwrite ($f, 'BM', 2);
173. fwrite ($f, pack ('VvvV', $bfSize, 0, 0, $bfOffBits));
174. fwrite ($f, pack ('VVVvvVVVVVV',40,$biWidth, $biHeight,1,24,0, $biSizeImage,0,0,0,0));
175. $numpad = $biStride - $biBPLine;
176. for ($y = $biHeight - 1; $y >= 0; --$y)
177. {
178. for ($x = 0; $x < $biWidth; ++$x)
179. {
180. $col = imagecolorat ($im, $x, $y);
181. fwrite ($f, pack ('V', $col), 3);
182. }
183. for ($i = 0; $i < $numpad; ++$i)
184. {
185. fwrite ($f, pack ('C', 0));
186. }
187. fclose ($f);
188. return true;
189. }
190. }
191. }
192. ?>
193. //----------调用-------------------------
194. $image=new ImageCheck();
195. $image->imagezoom("./Common/upload/news/20130712/liu.jpg","./Common/upload/news/20130712/liu.jpg",100,100,"#FFFFFF");
196. 同名将覆盖
复制代码
<embed id="ZeroClipboardMovie_1" src="http://www.thinkphp.cn/Public/common/zclip/ZeroClipboard.swf" loop="false" menu="false" quality="best" bgcolor="#ffffff" width="82" height="29" name="ZeroClipboardMovie_1" align="middle" allowscriptaccess="always" allowfullscreen="false" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" flashvars="id=1&width=82&height=29" wmode="transparent">`
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php 原生图片压缩方法
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