php生成缩略图的类代码

<?php
 



 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;
 
 }
 
 }
 
 }
 
 ?>