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PHP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);

}