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标题: 得到图片的长、宽及类型 [打印本页]

作者: tznktg 时间: 2007-10-4 17:37
标题: 得到图片的长、宽及类型
<?php
#########################################################
#                                                    #
# Release....: ImageVue.v1.4.PHP.NULL-WDYL             #
# Date.......: 01/30/04                               #
# Released...: WDYL                                  #
# Protection.: CallHome, License Check, Refferer Links  #
#                                                    #
#########################################################
define('GIF_SIG',    chr(0x47).chr(0x49).chr(0x46));  // 'GIF'

define('PNG_SIG',    chr(0x89).chr(0x50).chr(0x4E).chr(0x47).chr(0x0D).chr(0x0A).chr(0x1A).chr(0x0A));

define('JPG_SIG',    chr(0xFF).chr(0xD8).chr(0xFF));
define('JPG_SOS',    chr(0xDA)); // Start Of Scan - image data start
define('JPG_SOF0', chr(0xC0)); // Start Of Frame N
define('JPG_SOF1', chr(0xC1)); // N indicates which compression process
define('JPG_SOF2', chr(0xC2)); // Only SOF0-SOF2 are now in common use
define('JPG_SOF3', chr(0xC3));
// NB: codes C4 and CC are *not* SOF markers
define('JPG_SOF5', chr(0xC5));
define('JPG_SOF6', chr(0xC6));
define('JPG_SOF7', chr(0xC7));
define('JPG_SOF9', chr(0xC9));
define('JPG_SOF10', chr(0xCA));
define('JPG_SOF11', chr(0xCB));
// NB: codes C4 and CC are *not* SOF markers
define('JPG_SOF13', chr(0xCD));
define('JPG_SOF14', chr(0xCE));
define('JPG_SOF15', chr(0xCF));
define('JPG_EOI',    chr(0xD9)); // End Of Image (end of datastream)

function GetURLImageSize($urlpic) {
      if ($fd = @fopen($urlpic, 'rb')){
            $imgData = fread($fd, filesize($urlpic));
            fclose($fd);
            return GetDataImageSize($imgData);
      } else {
            return array('', '', '');
      }
}

function GetDataImageSize($imgData) {
      $height = '';
      $width  = '';
      $type = '';
      if ((substr($imgData, 0, 3) == GIF_SIG) && (strlen($imgData) > 10)) {
            $dim = unpack('v2dim', substr($imgData, 6, 4));
            $width  = $dim['dim1'];
            $height = $dim['dim2'];
            $type = 1;
      } elseif ((substr($imgData, 0, 8) == PNG_SIG) && (strlen($imgData) > 24)) {
            $dim = unpack('N2dim', substr($imgData, 16, 8));
            $width  = $dim['dim1'];
            $height = $dim['dim2'];
            $type = 3;
      } elseif ((substr($imgData, 0, 3) == JPG_SIG) && (strlen($imgData) > 4)) {
            ///////////////// JPG CHUNK SCAN ////////////////////
            $imgPos = 2;
            $type = 2;
            $buffer = strlen($imgData) - 2;
            while ($imgPos < strlen($imgData)) {
                     // synchronize to the marker 0xFF
                     $imgPos = strpos($imgData, 0xFF, $imgPos) + 1;
                     $marker = $imgData[$imgPos];
                     do {
                              $marker = ord($imgData[$imgPos++]);
                     } while ($marker == 255);
                     // find dimensions of block
                     switch (chr($marker)) {
                              // Grab width/height from SOF segment (these are acceptable chunk types)
                              case JPG_SOF0:
                              case JPG_SOF1:
                              case JPG_SOF2:
                              case JPG_SOF3:
                              case JPG_SOF5:
                              case JPG_SOF6:
                              case JPG_SOF7:
                              case JPG_SOF9:
                              case JPG_SOF10:
                              case JPG_SOF11:
                              case JPG_SOF13:
                              case JPG_SOF14:
                              case JPG_SOF15:
                                    $dim = unpack('n2dim', substr($imgData, $imgPos + 3, 4));
                                    $height = $dim['dim1'];
                                    $width  = $dim['dim2'];
                                    break 2; // found it so exit
                              case JPG_EOI:
                              case JPG_SOS:
                                    return false;    // End loop in case we find one of these markers
                              default:          // We're not interested in other markers
                                    $skiplen = (ord($imgData[$imgPos++]) << 8) + ord($imgData[$imgPos++]) - 2;
                                    // if the skip is more than what we've read in, read more
                                    $buffer -= $skiplen;
                                    if ($buffer < 512) { // if the buffer of data is too low, read more file.
                                             // $imgData .= fread( $fd,$skiplen+1024 );
                                             // $buffer += $skiplen + 1024;
                                             return false; // End loop in case we find run out of data
                                    }
                                    $imgPos += $skiplen;
                                    break;
                     } // endswitch check marker type
            } // endif loop through JPG chunks
      } // endif chk for valid file types

      return array($width, $height, $type);
} // end function

function ImageTypesLookup($imagetypeid) {
      static $ImageTypesLookup = array();
      if (empty($ImageTypesLookup)) {
            $ImageTypesLookup[1]  = 'gif';
            $ImageTypesLookup[2]  = 'jpg';
            $ImageTypesLookup[3]  = 'png';
            $ImageTypesLookup[4]  = 'swf';
            $ImageTypesLookup[5]  = 'psd';
            $ImageTypesLookup[6]  = 'bmp';
            $ImageTypesLookup[7]  = 'tiff (little-endian)';
            $ImageTypesLookup[8]  = 'tiff (big-endian)';
            $ImageTypesLookup[9]  = 'jpc';
            $ImageTypesLookup[10] = 'jp2';
            $ImageTypesLookup[11] = 'jpx';
            $ImageTypesLookup[12] = 'jb2';
            $ImageTypesLookup[13] = 'swc';
            $ImageTypesLookup[14] = 'iff';
      }
      return (isset($ImageTypesLookup[$imagetypeid]) ? $ImageTypesLookup[$imagetypeid] : '');
}

?>

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