php 生成缩略图

?php /* *生成缩略图 *$imgPath（图片路径）, $maxWidth（宽）, $maxHeight（高）, $directOutput = true（是否在页面输出）, $quality = 90, $verbose,$imageType（图片类型） * * */ function resizeImg($imgPath, $maxWidth, $maxHeight, $directOutput =

/*

*生成缩略图

*$imgPath（图片路径）, $maxWidth（宽）, $maxHeight（高）, $directOutput = true（是否在页面输出）, $quality = 90, $verbose,$imageType（图片类型）

*

*

*/
function resizeImg($imgPath, $maxWidth, $maxHeight, $directOutput = true, $quality = 90, $verbose,$imageType)
  {
    $size = getimagesize($imgPath);

    //print_r($size);exit;
     // break and return false if failed to read image infos
    if(!$size){
      if($verbose && !$directOutput)echo "
Not able to read image infos.
";
     
      return false;
    }
  
     // relation: width/height
    $relation = $size[0]/$size[1];
     // maximal size (if parameter == false, no resizing will be made)
    $maxSize = array($maxWidth?$maxWidth:$size[0],$maxHeight?$maxHeight:$size[1]);
     // declaring array for new size (initial value = original size)
    $newSize = $size;
     // width/height relation
    $relation = array($size[1]/$size[0], $size[0]/$size[1]);
  //print_r($size);
  //echo "
";
  //print_r($relation);exit;
  
   if(($newSize[0] > $maxWidth))
   {
    $newSize[0]=$maxSize[0];
    $newSize[1]=$newSize[0]*$relation[0];
   }
      
   if(($newSize[1] > $maxHeight))
   {
    $newSize[1]=$maxSize[1];
    $newSize[0]=$newSize[1]*$relation[1];
   }
   
   
    // create image
      switch($size[2])
      {
     case 1:
       if(function_exists("imagecreatefromgif"))
       {
      $originalImage = imagecreatefromgif($imgPath);
       }else{
      if($verbose && !$directOutput)echo "
No GIF support in this php installation, sorry.
";
      return false;
       }
       break;
     case 2: $originalImage = imagecreatefromjpeg($imgPath); break;
     case 3: $originalImage = imagecreatefrompng($imgPath); break;
     default:
       if($verbose && !$directOutput)echo "
No valid image type.
";
       return false;
      }
  
    // create new image
  
      $resizedImage = imagecreatetruecolor($newSize[0], $newSize[1]);
  
      imagecopyresampled($resizedImage, $originalImage,0, 0, 0, 0,$newSize[0], $newSize[1], $size[0], $size[1]);
  
   $rz=$imgPath;
  
    // output or save
      if($directOutput)
    {
     imagejpeg($resizedImage);
     }
     else
    {
     
     $exp=explode(".",$imgPath);
     $extension=end($exp);//$exp[count($exp)-1];
     $newimage=$imageType.".".$extension;
     $rz=preg_replace("//.([a-zA-Z]{3,4})$/",$newimage,$imgPath);
        imagejpeg($resizedImage, $rz, $quality);
     }
    // return true if successfull
      return $rz;
  } // End function Resize Image 

 

//调用
 resizeImg("var/chen.jpg", 125 ,75, false, 100, 0,"_thumb");
?>