php生成缩略图的类代码

  <?php

  /**

  * 功能:生成缩略图

  * 作者:phpox

  * 日期:Thu May 17 09:57:05 CST 2007

  */

  class CreatMiniature

  {

  //公共变量

  var $srcFile=""; //原图

  var $echoType; //输出图片类型,link--不保存为文件;file--保存为文件

  var $im=""; //临时变量

  var $srcW=""; //原图宽

  var $srcH=""; //原图高

  //设置变量及初始化

  function SetVar($srcFile,$echoType)

  {

  if (!file_exists($srcFile)){

  echo '源图片文件不存在!';

  exit();

  }

  $this->srcFile=$srcFile;

  $this->echoType=$echoType;

  $info = "";

  $data = GetImageSize($this->srcFile,$info);

  switch ($data[2])

  {

  case 1:

  if(!function_exists("imagecreatefromgif")){

  echo "你的GD库不能使用GIF格式的图片,请使用Jpeg或PNG格式!<a href='javascript:go(-1);'>返回</a>";

  exit();

  }

  $this->im = ImageCreateFromGIF($this->srcFile);

  break;

  case 2:

  if(!function_exists("imagecreatefromjpeg")){

  echo "你的GD库不能使用jpeg格式的图片,请使用其它格式的图片!<a href='javascript:go(-1);'>返回</a>";

  exit();

  }

  $this->im = ImageCreateFromJpeg($this->srcFile);

  break;

  case 3:

  $this->im = ImageCreateFromPNG($this->srcFile);

  break;

  }

  $this->srcW=ImageSX($this->im);

  $this->srcH=ImageSY($this->im);

  }

  //生成扭曲型缩图

  function Distortion($toFile,$toW,$toH)

  {

  $cImg=$this->CreatImage($this->im,$toW,$toH,0,0,0,0,$this->srcW,$this->srcH);

  return $this->EchoImage($cImg,$toFile);

  ImageDestroy($cImg);

  }

  //生成按比例缩放的缩图

  function Prorate($toFile,$toW,$toH)

  {

  $toWH=$toW/$toH;

  $srcWH=$this->srcW/$this->srcH;

  if($toWH<=$srcWH)

  {

  $ftoW=$toW;

  $ftoH=$ftoW*($this->srcH/$this->srcW);

  }

  else

  {

  $ftoH=$toH;

  $ftoW=$ftoH*($this->srcW/$this->srcH);

  }

  if($this->srcW>$toW||$this->srcH>$toH)

  {

  $cImg=$this->CreatImage($this->im,$ftoW,$ftoH,0,0,0,0,$this->srcW,$this->srcH);

  return $this->EchoImage($cImg,$toFile);

  ImageDestroy($cImg);

  }

  else

  {

  $cImg=$this->CreatImage($this->im,$this->srcW,$this->srcH,0,0,0,0,$this->srcW,$this->srcH);

  return $this->EchoImage($cImg,$toFile);

  ImageDestroy($cImg);

  }

  }

  //生成最小裁剪后的缩图

  function Cut($toFile,$toW,$toH)

  {

  $toWH=$toW/$toH;

  $srcWH=$this->srcW/$this->srcH;

  if($toWH<=$srcWH)

  {

  $ctoH=$toH;

  $ctoW=$ctoH*($this->srcW/$this->srcH);

  }

  else

  {

  $ctoW=$toW;

  $ctoH=$ctoW*($this->srcH/$this->srcW);

  }

  $allImg=$this->CreatImage($this->im,$ctoW,$ctoH,0,0,0,0,$this->srcW,$this->srcH);

  $cImg=$this->CreatImage($allImg,$toW,$toH,0,0,($ctoW-$toW)/2,($ctoH-$toH)/2,$toW,$toH);

  return $this->EchoImage($cImg,$toFile);

  ImageDestroy($cImg);

  ImageDestroy($allImg);

  }

  //生成背景填充的缩图

  function BackFill($toFile,$toW,$toH,$bk1=255,$bk2=255,$bk3=255)

  {

  $toWH=$toW/$toH;

  $srcWH=$this->srcW/$this->srcH;

  if($toWH<=$srcWH)

  {

  $ftoW=$toW;

  $ftoH=$ftoW*($this->srcH/$this->srcW);

  }

  else

  {

  $ftoH=$toH;

  $ftoW=$ftoH*($this->srcW/$this->srcH);

  }

  if(function_exists("imagecreatetruecolor"))

  {

  @$cImg=ImageCreateTrueColor($toW,$toH);

  if(!$cImg)

  {

  $cImg=ImageCreate($toW,$toH);

  }

  }

  else

  {

  $cImg=ImageCreate($toW,$toH);

  }

  $backcolor = imagecolorallocate($cImg, $bk1, $bk2, $bk3); //填充的背景颜色

  ImageFilledRectangle($cImg,0,0,$toW,$toH,$backcolor);

  if($this->srcW>$toW||$this->srcH>$toH)

  {

  $proImg=$this->CreatImage($this->im,$ftoW,$ftoH,0,0,0,0,$this->srcW,$this->srcH);

  if($ftoW<$toW)

  {

  ImageCopy($cImg,$proImg,($toW-$ftoW)/2,0,0,0,$ftoW,$ftoH);

  }

  else if($ftoH<$toH)

  {

  ImageCopy($cImg,$proImg,0,($toH-$ftoH)/2,0,0,$ftoW,$ftoH);

  }

  else

  {

  ImageCopy($cImg,$proImg,0,0,0,0,$ftoW,$ftoH);

  }

  }

  else

  {

  ImageCopyMerge($cImg,$this->im,($toW-$ftoW)/2,($toH-$ftoH)/2,0,0,$ftoW,$ftoH,100);

  }

  return $this->EchoImage($cImg,$toFile);

  ImageDestroy($cImg);

  }

  function CreatImage($img,$creatW,$creatH,$dstX,$dstY,$srcX,$srcY,$srcImgW,$srcImgH)

  {

  if(function_exists("imagecreatetruecolor"))

  {

  @$creatImg = ImageCreateTrueColor($creatW,$creatH);

  if($creatImg)

  ImageCopyResampled($creatImg,$img,$dstX,$dstY,$srcX,$srcY,$creatW,$creatH,$srcImgW,$srcImgH);

  else

  {

  $creatImg=ImageCreate($creatW,$creatH);

  ImageCopyResized($creatImg,$img,$dstX,$dstY,$srcX,$srcY,$creatW,$creatH,$srcImgW,$srcImgH);

  }

  }

  else

  {

  $creatImg=ImageCreate($creatW,$creatH);

  ImageCopyResized($creatImg,$img,$dstX,$dstY,$srcX,$srcY,$creatW,$creatH,$srcImgW,$srcImgH);

  }

  return $creatImg;

  }

  //输出图片,link---只输出,不保存文件。file--保存为文件

  function EchoImage($img,$to_File)

  {

  switch($this->echoType)

  {

  case "link":

  if(function_exists('imagejpeg')) return ImageJpeg($img);

  else return ImagePNG($img);

  break;

  case "file":

  if(function_exists('imagejpeg')) return ImageJpeg($img,$to_File);

  else return ImagePNG($img,$to_File);

  break;

  }

  }

  }

  ?>