PHP实现显示照片exif信息的方法

<?
/**
* 获取图象信息的函数
* 一个全面获取图象信息的函数
* @access public
* @param string $img 图片路径
* @return array
*/
function getimageinfoval($imageinfo,$val_arr) {
  $infoval  =  "未知";
  foreach($val_arr as $name=>$val) {
    if ($name==$imageinfo) {
      $infoval  =  &$val;
      break;
    }
  }
  return $infoval;
}
function getimageinfo($img) {
  $imgtype      =  array("", "gif", "jpg", "png", "swf", "psd", "bmp", "tiff(intel byte order)", "tiff(motorola byte order)", "jpc", "jp2", "jpx", "jb2", "swc", "iff", "wbmp", "xbm");
  $orientation    =  array("", "top left side", "top right side", "bottom right side", "bottom left side", "left side top", "right side top", "right side bottom", "left side bottom");
  $resolutionunit    =  array("", "", "英寸", "厘米");
  $ycbcrpositioning  =  array("", "the center of pixel array", "the datum point");
  $exposureprogram  =  array("未定义", "手动", "标准程序", "光圈先决", "快门先决", "景深先决", "运动模式", "肖像模式", "风景模式");
  $meteringmode_arr  =  array(
    "0"    =>  "未知",
    "1"    =>  "平均",
    "2"    =>  "*重点平均测光",
    "3"    =>  "点测",
    "4"    =>  "分区",
    "5"    =>  "评估",
    "6"    =>  "局部",
    "255"  =>  "其他"
    );
  $lightsource_arr  =  array(
    "0"    =>  "未知",
    "1"    =>  "日光",
    "2"    =>  "荧光灯",
    "3"    =>  "钨丝灯",
    "10"  =>  "闪光灯",
    "17"  =>  "标准灯光a",
    "18"  =>  "标准灯光b",
    "19"  =>  "标准灯光c",
    "20"  =>  "d55",
    "21"  =>  "d65",
    "22"  =>  "d75",
    "255"  =>  "其他"
    );
  $flash_arr      =  array(
    "0"    =>  "flash did not fire",
    "1"    =>  "flash fired",
    "5"    =>  "flash fired but strobe return light not detected",
    "7"    =>  "flash fired and strobe return light detected",
    );
  
  $exif = exif_read_data ($img,"ifd0");
  if ($exif===false) {
    $new_img_info  =  array ("文件信息"    =>  "没有图片exif信息");
  }
  else
  {
    $exif = exif_read_data ($img,0,true);
    $new_img_info  =  array (
      "文件信息"    =>  "-----------------------------",
      "文件名"    =>  $exif[file][filename],
      "文件类型"    =>  $imgtype[$exif[file][filetype]],
      "文件格式"    =>  $exif[file][mimetype],
      "文件大小"    =>  $exif[file][filesize],
      "时间戳"    =>  date("y-m-d h:i:s",$exif[file][filedatetime]),
      "图像信息"    =>  "-----------------------------",
      "图片说明"    =>  $exif[ifd0][imagedescription],
      "制造商"    =>  $exif[ifd0][make],
      "型号"      =>  $exif[ifd0][model],
      "方向"      =>  $orientation[$exif[ifd0][orientation]],
      "水平分辨率"  =>  $exif[ifd0][xresolution].$resolutionunit[$exif[ifd0][resolutionunit]],
      "垂直分辨率"  =>  $exif[ifd0][yresolution].$resolutionunit[$exif[ifd0][resolutionunit]],
      "创建软件"    =>  $exif[ifd0][software],
      "修改时间"    =>  $exif[ifd0][datetime],
      "作者"      =>  $exif[ifd0][artist],
      "ycbcr位置控制"  =>  $ycbcrpositioning[$exif[ifd0][ycbcrpositioning]],
      "版权"      =>  $exif[ifd0][copyright],
      "摄影版权"    =>  $exif[computed][copyright.photographer],
      "编辑版权"    =>  $exif[computed][copyright.editor],
      "拍摄信息"    =>  "-----------------------------",
      "exif版本"    =>  $exif[exif][exifversion],
      "flashpix版本"  =>  "ver. ".number_format($exif[exif][flashpixversion]/100,2),
      "拍摄时间"    =>  $exif[exif][datetimeoriginal],
      "数字化时间"  =>  $exif[exif][datetimedigitized],
      "拍摄分辨率高"  =>  $exif[computed][height],
      "拍摄分辨率宽"  =>  $exif[computed][width],
      /*
      the actual aperture value of lens when the image was taken.
      unit is apex.
      to convert this value to ordinary f-number(f-stop),
      calculate this value's power of root 2 (=1.4142).
      for example, if the aperturevalue is '5', f-number is pow(1.41425,5) = f5.6.
      */
      "光圈"      =>  $exif[exif][aperturevalue],
      "快门速度"    =>  $exif[exif][shutterspeedvalue],
      "快门光圈"    =>  $exif[computed][aperturefnumber],
      "最大光圈值"  =>  "f".$exif[exif][maxaperturevalue],
      "曝光时间"    =>  $exif[exif][exposuretime],
      "f-number"    =>  $exif[exif][fnumber],
      "测光模式"    =>  getimageinfoval($exif[exif][meteringmode],$meteringmode_arr),
      "光源"      =>  getimageinfoval($exif[exif][lightsource], $lightsource_arr),
      "闪光灯"    =>  getimageinfoval($exif[exif][flash], $flash_arr),
      "曝光模式"    =>  ($exif[exif][exposuremode]==1?"手动":"自动"),
      "白平衡"    =>  ($exif[exif][whitebalance]==1?"手动":"自动"),
      "曝光程序"    =>  $exposureprogram[$exif[exif][exposureprogram]],
      /*
      brightness of taken subject, unit is apex. to calculate exposure(ev) from brigtnessvalue(bv), you must add sensitivityvalue(sv).
      ev=bv+sv  sv=log((isospeedrating/3.125),2)
      iso100:sv=5, iso200:sv=6, iso400:sv=7, iso125:sv=5.32. 
      */
      "曝光补偿"    =>  $exif[exif][exposurebiasvalue]."ev",
      "iso感光度"    =>  $exif[exif][isospeedratings],
      "分量配置"    =>  (bin2hex($exif[exif][componentsconfiguration])=="01020300"?"ycbcr":"rgb"),//'0x04,0x05,0x06,0x00'="rgb" '0x01,0x02,0x03,0x00'="ycbcr"
      "图像压缩率"  =>  $exif[exif][compressedbitsperpixel]."bits/pixel",
      "对焦距离"    =>  $exif[computed][focusdistance]."m",
      "焦距"      =>  $exif[exif][focallength]."mm",
      "等价35mm焦距"  =>  $exif[exif][focallengthin35mmfilm]."mm",
      /*
      stores user comment. this tag allows to use two-byte character code or unicode. first 8 bytes describe the character code. 'jis' is a japanese character code (known as kanji).
      '0x41,0x53,0x43,0x49,0x49,0x00,0x00,0x00':ascii
      '0x4a,0x49,0x53,0x00,0x00,0x00,0x00,0x00':jis
      '0x55,0x4e,0x49,0x43,0x4f,0x44,0x45,0x00':unicode
      '0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00':undefined
      */
      "用户注释编码"  =>  $exif[computed][usercommentencoding],
      "用户注释"    =>  $exif[computed][usercomment],
      "色彩空间"    =>  ($exif[exif][colorspace]==1?"srgb":"uncalibrated"),
      "exif图像宽度"  =>  $exif[exif][exifimagelength],
      "exif图像高度"  =>  $exif[exif][exifimagewidth],
      "文件来源"    =>  (bin2hex($exif[exif][filesource])==0x03?"digital still camera":"unknown"),
      "场景类型"    =>  (bin2hex($exif[exif][scenetype])==0x01?"a directly photographed image":"unknown"),
      "缩略图文件格式"  =>  $exif[computed][thumbnail.filetype],
      "缩略图mime格式"  =>  $exif[computed][thumbnail.mimetype]
    );
  }
  return $new_img_info;
}

$innerhtml  =  "";
$exif  =  getimageinfo($_get['img']);
$innerhtml  .=  "<table>";

foreach($exif as $name=>$val) {
  $innerhtml  .=  "<tr><td>{$name}</td><td>{$val}</td></tr>";
}

$innerhtml  .=  "<tr><td colspan=\"2\">";
if ($_get['img']) {
  $image = exif_thumbnail($_get['img']);
} else {
  $image = false;
}
if ($image!==false) {
  $innerhtml  .=  "<img src=\"thumbnail.php?img=".$_get['img']."\">";
} else {
  // no thumbnail available, handle the error here
  $innerhtml  .=  "no thumbnail available";
}

$innerhtml  .=  "</td></tr></table>";
?>
<html>
<head> 
<title>图片信息</title>
<meta http-equiv="content-type" content="text/html; charset=??????">
</head>
<body>
<script>
<!--
//初始化内容值
parent.followtd<?=$_get['r_id'];?>.innerhtml='<?=$innerhtml;?>';
//已读取
parent.document.images.followimg<?=$_get['r_id'];?>.loaded='yes';
-->
</script>
</body>
</html>