lib/thumb/thumb.gd.php

   1 <?php\r
   2 /**\r
   3  * Thumbnail Generate API: GD Wrapper\r
   4  *\r
   5  * 提供程式便於以 GD Library 生成預覽圖的物件\r
   6  *\r
   7  * @package PMCLibrary\r
   8  * @version $Id: thumb.gd.php 603 2008-02-22 14:12:29Z scribe $\r
   9  * @date $Date: 2008-02-22 22:12:29 +0800 (星期五, 22 二月 2008) $\r
  10  */\r
  11 \r
  12 class ThumbWrapper{\r
  13         var $sourceFile, $sourceWidth, $sourceHeight, $thumbWidth, $thumbHeight, $thumbQuality;\r
  14 \r
  15         function ThumbWrapper($sourceFile='', $sourceWidth=0, $sourceHeight=0){\r
  16                 $this->sourceFile = $sourceFile;\r
  17                 $this->sourceWidth = $sourceWidth;\r
  18                 $this->sourceHeight = $sourceHeight;\r
  19         }\r
  20 \r
  21         function _GetLeftShiftCount($dwVal,$len=4) {\r
  22                 $nCount = 0;\r
  23                 for ($i=0; $i<$len * 8; $i++) {\r
  24                         if ($dwVal & 1) $nCount++;\r
  25                         $dwVal >>= 1;\r
  26                 }\r
  27                 return (8 - $nCount);\r
  28         }\r
  29         function _GetRightShiftCount($dwVal,$len=4) {\r
  30                 for ($i=0; $i<$len * 8; $i++) {\r
  31                         if ($dwVal & 1) return $i;\r
  32                         $dwVal >>= 1;\r
  33                 }\r
  34                 return -1;\r
  35         }\r
  36 \r
  37         /* ImageCreateFromBMP : 讓GD可處理BMP圖檔\r
  38         此為修改後最適化版本。原出處：http://www.php.net/imagecreate#53879\r
  39         原作宣告：\r
  40         *****************************\r
  41         Function: ImageCreateFromBMP\r
  42         Author: DHKold\r
  43         Contact: admin@dhkold.com\r
  44         Date: The 15th of June 2005\r
  45         Version: 2.0B\r
  46         *****************************/\r
  47         function _ImageCreateFromBMP($filename){\r
  48                 // 序章：以二進位模式開啟檔案流\r
  49                 if(!$f1 = fopen($filename, 'rb')) return FALSE;\r
  50 \r
  51                 // 第一步：讀取BMP檔頭\r
  52                 $FILE = unpack('vfile_type/Vfile_size/Vreserved/Vbitmap_offset', fread($f1, 14));\r
  53                 if($FILE['file_type']!=19778) return FALSE; // BM\r
  54 \r
  55                 // 第二步：讀取BMP資訊\r
  56                 // 僅支援BITMAPINFOHEADER，不支援BITMAPV4HEADER及BITMAPV5HEADER\r
  57                 $BMP = unpack('Vheader_size/Vwidth/Vheight/vplanes/vbits_per_pixel/Vcompression/Vsize_bitmap/Vhoriz_resolution/Vvert_resolution/Vcolors_used/Vcolors_important', fread($f1, 40));\r
  58                 $BMP['colors'] = pow(2, $BMP['bits_per_pixel']);\r
  59                 if($BMP['size_bitmap']==0) $BMP['size_bitmap'] = $FILE['file_size'] - $FILE['bitmap_offset'];\r
  60                 $BMP['bytes_per_pixel'] = $BMP['bits_per_pixel'] / 8;\r
  61                 $BMP['decal'] = ($BMP['width'] * $BMP['bytes_per_pixel'] / 4);\r
  62                 $BMP['decal'] -= floor($BMP['width'] * $BMP['bytes_per_pixel'] / 4);\r
  63                 $BMP['decal'] = 4 - (4 * $BMP['decal']);\r
  64                 if($BMP['decal']==4) $BMP['decal'] = 0;\r
  65 \r
  66                 // 第三步：讀取色盤資訊\r
  67                 $PALETTE = array();\r
  68                 if ($BMP['colors'] <=256 || $BMP['compression'] == 3) {\r
  69                         if($BMP['compression'] == 3) // BI_BITFIELDS\r
  70                                 $PALETTE = unpack('V3', fread($f1,12));\r
  71                         else\r
  72                                 $PALETTE = unpack('V'.$BMP['colors'], fread($f1,$BMP['colors']*4));\r
  73                 }\r
  74                 if($BMP['compression'] == 3) // BI_BITFIELDS\r
  75                         $mask = array(array($PALETTE[1],$PALETTE[2],$PALETTE[3]),\r
  76                                 array($this->_GetRightShiftCount($PALETTE[1]),$this->_GetRightShiftCount($PALETTE[2]),$this->_GetRightShiftCount($PALETTE[3])),\r
  77                                 array($this->_GetLeftShiftCount($PALETTE[1]),$this->_GetLeftShiftCount($PALETTE[2]),$this->_GetLeftShiftCount($PALETTE[3])));\r
  78                 else {\r
  79                         if($BMP['colors'] == 65536) $mask = array(array(0x7C00,0x3E0,0x1F),array(10,5,0),array(3,3,3));\r
  80                 }\r
  81 \r
  82                 // 第四步：關閉檔案，變換每一個畫素\r
  83                 $IMG = fread($f1, $BMP['size_bitmap']);\r
  84                 fclose($f1);\r
  85                 $VIDE = chr(0);\r
  86 \r
  87                 $res = ImageCreateTrueColor($BMP['width'], $BMP['height']);\r
  88                 $P = 0;\r
  89                 $Y = $BMP['height'] - 1;\r
  90 \r
  91                 if($BMP['compression'] == 1 && $BMP['colors'] == 256) { // BI_RLE8\r
  92                         $imgDataLen=strlen($IMG);\r
  93                         $RLEData='';\r
  94                         while(true) {\r
  95                                 $prefix=ord(substr($IMG, floor($P++), 1));\r
  96                                 $suffix=ord(substr($IMG, floor($P++), 1));\r
  97 \r
  98                                 if(($prefix==0)&&($suffix==1)) break; // end of RLE stream\r
  99                                 if($P>=$imgDataLen) break;\r
 100 \r
 101                                 while(!(($prefix==0)&&($suffix==0))){ // ! end of RLE line\r
 102                                         if($prefix==0){ // Command\r
 103                                                 $RLEData.=substr($IMG, floor($P), $suffix);\r
 104                                                 $P+=$suffix;\r
 105                                                 if($P%2==1) $P++;\r
 106                                         } elseif($prefix>0){ // Repeat\r
 107                                                 for($r=0;$r<$prefix;$r++)\r
 108                                                         $RLEData.=chr($suffix);\r
 109                                         }\r
 110                                         $prefix=ord(substr($IMG, floor($P++), 1));\r
 111                                         $suffix=ord(substr($IMG, floor($P++), 1));\r
 112                                 }\r
 113                                 for($X=0;$X<strlen($RLEData);$X++) // Write\r
 114                                         ImageSetPixel($res, $X, $Y, $PALETTE[ord($RLEData[$X])+1]);\r
 115                                 $RLEData='';\r
 116                                 $Y--;\r
 117                         }\r
 118                 } elseif($BMP['compression'] == 2 && $BMP['colors'] == 16) { // BI_RLE4\r
 119                         $imgDataLen=strlen($IMG);\r
 120                         $RLEData='';\r
 121                         while(true) {\r
 122                                 $prefix=ord(substr($IMG, floor($P++), 1));\r
 123                                 $suffix=ord(substr($IMG, floor($P++), 1));\r
 124 \r
 125                                 if(($prefix==0)&&($suffix==1)) break; // end of RLE stream\r
 126                                 if($P>=$imgDataLen) break;\r
 127 \r
 128                                 while(!(($prefix==0)&&($suffix==0))){ // ! end of RLE line\r
 129                                         if($prefix==0){ // Command\r
 130                                                 for($h=0;$h<$suffix;$h++) {\r
 131                                                         $COLOR = ord(substr($IMG, floor($P), 1));\r
 132                                                         $RLEData.=($h%2==0)?chr($COLOR >> 4):chr($COLOR & 0x0F);\r
 133                                                         $P += $BMP['bytes_per_pixel'];\r
 134                                                 }\r
 135                                                 $P=ceil($P);\r
 136                                                 if($P%2==1) $P++;\r
 137                                         } elseif($prefix>0){ // Repeat\r
 138                                                 for($r=0;$r<$prefix;$r++)\r
 139                                                         $RLEData.=($r%2==0)?chr($suffix >> 4):chr($suffix & 0x0F);\r
 140                                         }\r
 141                                         $prefix=ord(substr($IMG, floor($P++), 1));\r
 142                                         $suffix=ord(substr($IMG, floor($P++), 1));\r
 143                                 }\r
 144 \r
 145                                 for($X=0;$X<strlen($RLEData);$X++) // Write\r
 146                                         ImageSetPixel($res, $X, $Y, $PALETTE[ord($RLEData[$X])+1]);\r
 147                                 $RLEData='';\r
 148                                 $Y--;\r
 149 \r
 150                         }\r
 151                 } else {\r
 152                         while($Y >= 0){\r
 153                                 $X = 0;\r
 154                                 while($X < $BMP['width']){\r
 155                                         switch($BMP['bits_per_pixel']){\r
 156                                                 case 32: \r
 157                                                         $COLOR = unpack('V', substr($IMG, $P, 4));\r
 158                                                         $COLOR[1] &= 0xFFFFFF; // 不處理Alpha\r
 159                                                         break;\r
 160                                                 case 24: $COLOR = unpack('V', substr($IMG, $P, 3).$VIDE); break;\r
 161                                                 case 16:\r
 162                                                         $COLOR = unpack("v",substr($IMG,$P,2));\r
 163                                                         $COLOR[1] = (((($COLOR[1] & $mask[0][0])>>$mask[1][0])<<$mask[2][0])<<16) |\r
 164                                                                 (((($COLOR[1] & $mask[0][1])>>$mask[1][1])<<$mask[2][1])<<8) |\r
 165                                                                 ((($COLOR[1] & $mask[0][2])>>$mask[1][2])<<$mask[2][2]);\r
 166                                                         break;\r
 167                                                 case 8: $COLOR = unpack('n', $VIDE.substr($IMG, $P, 1)); break;\r
 168                                                 case 4:\r
 169                                                         $COLOR = unpack('n', $VIDE.substr($IMG, floor($P), 1));\r
 170                                                         if(($P*2)%2==0) $COLOR[1] = ($COLOR[1] >> 4);\r
 171                                                         else $COLOR[1] = ($COLOR[1] & 0x0F);\r
 172                                                         break;\r
 173                                                 case 1:\r
 174                                                         $COLOR = unpack('n', $VIDE.substr($IMG, floor($P), 1));\r
 175                                                         switch(($P * 8) % 8){\r
 176                                                                 case 0: $COLOR[1] = $COLOR[1] >> 7; break;\r
 177                                                                 case 1: $COLOR[1] = ($COLOR[1] & 0x40) >> 6; break;\r
 178                                                                 case 2: $COLOR[1] = ($COLOR[1] & 0x20) >> 5; break;\r
 179                                                                 case 3: $COLOR[1] = ($COLOR[1] & 0x10) >> 4; break;\r
 180                                                                 case 4: $COLOR[1] = ($COLOR[1] & 0x8) >> 3; break;\r
 181                                                                 case 5: $COLOR[1] = ($COLOR[1] & 0x4) >> 2; break;\r
 182                                                                 case 6: $COLOR[1] = ($COLOR[1] & 0x2) >> 1; break;\r
 183                                                                 case 7: $COLOR[1] = ($COLOR[1] & 0x1);\r
 184                                                         }\r
 185                                                         break;\r
 186                                                 default:\r
 187                                                         return FALSE;\r
 188                                         }\r
 189                                         if($BMP['bits_per_pixel']<16) $COLOR[1] = $PALETTE[$COLOR[1]+1];\r
 190                                         ImageSetPixel($res, $X, $Y, $COLOR[1]);\r
 191                                         $X++;\r
 192                                         $P += $BMP['bytes_per_pixel'];\r
 193                                 }\r
 194                                 $Y--;\r
 195                                 $P += $BMP['decal'];\r
 196                         }\r
 197                 }\r
 198 \r
 199                 // 終章：回傳新圖像\r
 200                 return $res;\r
 201         }\r
 202 \r
 203         function getClass(){\r
 204                 $str = 'GD Wrapper';\r
 205                 if($this->isWorking()){\r
 206                         $a = gd_info(); $str .= ' : '.$a['GD Version'];\r
 207                 }\r
 208                 return $str;\r
 209         }\r
 210 \r
 211         function isWorking(){\r
 212                 return extension_loaded('gd') && function_exists('ImageCreateTrueColor') && function_exists('ImageCopyResampled');\r
 213         }\r
 214 \r
 215         function setThumbnailConfig($thumbWidth, $thumbHeight, $thumbQuality=50){\r
 216                 $this->thumbWidth = $thumbWidth;\r
 217                 $this->thumbHeight = $thumbHeight;\r
 218                 $this->thumbQuality = $thumbQuality;\r
 219         }\r
 220 \r
 221         function makeThumbnailtoFile($destFile){\r
 222                 if(!$this->isWorking()) return false;\r
 223                 switch(strtolower(strrchr($this->sourceFile, '.'))){ // 取出副檔名\r
 224                         case '.jpg':\r
 225                                 $im_in = @ImageCreateFromJPEG($this->sourceFile); break;\r
 226                         case '.gif':\r
 227                                 $im_in = @ImageCreateFromGIF($this->sourceFile); break;\r
 228                         case '.png':\r
 229                                 $im_in = @ImageCreateFromPNG($this->sourceFile); break;\r
 230                         case '.rle':\r
 231                         case '.bmp':\r
 232                                 $im_in = $this->_ImageCreateFromBMP($this->sourceFile); break;\r
 233                         default:\r
 234                                 return false;\r
 235                 }\r
 236                 if(!$im_in) return false;\r
 237                 $im_out = ImageCreateTrueColor($this->thumbWidth, $this->thumbHeight);\r
 238                 ImageCopyResampled($im_out, $im_in, 0, 0, 0, 0, $this->thumbWidth, $this->thumbHeight, $this->sourceWidth, $this->sourceHeight);\r
 239                 ImageJPEG($im_out, $destFile, $this->thumbQuality);\r
 240                 ImageDestroy($im_in); ImageDestroy($im_out);\r
 241                 return true;\r
 242         }\r
 243 }\r
 244 ?>