<?php//創建壓縮圖function _create_thumbnail($srcFile, $toW, $toH, $toFile=""){  if ($toFile == "")  {    $toFile = $srcFile;  }  $info = "";  $data = getimagesize($srcFile, $info);  if (!$data)    return false;  //將文件載入到資源變量im中  switch ($data[2])  {    case 1:      $im = imagecreatefromgif($srcFile);      break;    case 2:      $im = imagecreatefromjpeg($srcFile);      break;    case 3:      $im = imagecreatefrompng($srcFile);      break;  }  //計算縮略圖的寬高  $srcW = imagesx($im);  $srcH = imagesy($im);  $toWH = $toW / $toH;  $srcWH = $srcW / $srcH;  if ($toWH <= $srcWH)  {    $ftoW = $toW;    $ftoH = (int)($ftoW * ($srcH / $srcW));  }  else  {    $ftoH = $toH;    $ftoW = (int)($ftoH * ($srcW / $srcH));  }  if (function_exists("imagecreatetruecolor"))  {    $ni = imagecreatetruecolor($ftoW, $ftoH); //新建一個真彩色圖像    if ($ni)    {      //重采樣拷貝部分圖像并調整大小 可保持較好的清晰度      imagecopyresampled($ni, $im, 0, 0, 0, 0, $ftoW, $ftoH, $srcW, $srcH);    }    else    {      //拷貝部分圖像并調整大小      $ni = imagecreate($ftoW, $ftoH);      imagecopyresized($ni, $im, 0, 0, 0, 0, $ftoW, $ftoH, $srcW, $srcH);    }  }  else  {    $ni = imagecreate($ftoW, $ftoH);    imagecopyresized($ni, $im, 0, 0, 0, 0, $ftoW, $ftoH, $srcW, $srcH);  }  //保存到文件 統一為.png格式  imagepng($ni, $toFile); //以 PNG 格式將圖像輸出到瀏覽器或文件  ImageDestroy($ni);  ImageDestroy($im);}?>