php生成图片缩略图类程序

<?php
class resizeimage
{
    //图片类型
    var $type;
    //实际宽度
    var $width;
    //实际高度
    var $height;
    //改变后的宽度
    var $resize_width;
    //改变后的高度
    var $resize_height;
    //是否裁图
    var $cut;
    //源图象
    var $srcimg;
    //目标图象地址
    var $dstimg;
    //临时创建的图象
    var $im;

    function resizeimage($img, $wid, $hei,$c,$dstpath)
    {
        $this->srcimg = $img;
        $this->resize_width = $wid;
        $this->resize_height = $hei;
        $this->cut = $c;
        //图片的类型
  
$this->type = strtolower(substr(strrchr($this->srcimg,"."),1));

        //初始化图象
        $this->initi_img();
        //目标图象地址
        $this -> dst_img($dstpath);
        //--
        $this->width = imagesx($this->im);
        $this->height = imagesy($this->im);
        //生成图象
        $this->newimg();
        ImageDestroy ($this->im);
    }
    function newimg()
    {
        //改变后的图象的比例
        $resize_ratio = ($this->resize_width)/($this->resize_height);
        //实际图象的比例
        $ratio = ($this->width)/($this->height);
        if(($this->cut)=="1")
        //裁图
        {
            if($ratio>=$resize_ratio)
            //高度优先
            {
                $newimg = imagecreatetruecolor($this->resize_width,$this->resize_height);
                imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width,$this-

>resize_height, (($this->height)*$resize_ratio), $this->height);
                ImageJpeg ($newimg,$this->dstimg);
            }
            if($ratio<$resize_ratio)
            //宽度优先
            {
                $newimg = imagecreatetruecolor($this->resize_width,$this->resize_height);
                imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width, $this-

>resize_height, $this->width, (($this->width)/$resize_ratio));
                ImageJpeg ($newimg,$this->dstimg);
            }
        }
        else
        //不裁图
        {
            if($ratio>=$resize_ratio)
            {
                $newimg = imagecreatetruecolor($this->resize_width,($this->resize_width)/$ratio);
                imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width, ($this-

>resize_width)/$ratio, $this->width, $this->height);
                ImageJpeg ($newimg,$this->dstimg);
            }
            if($ratio<$resize_ratio)
            {
                $newimg = imagecreatetruecolor(($this->resize_height)*$ratio,$this->resize_height);
                imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, ($this->resize_height)*$ratio,

$this->resize_height, $this->width, $this->height);
                ImageJpeg ($newimg,$this->dstimg);
            }
        }
    }
    //初始化图象
    function initi_img()
    {
        if($this->type=="jpg")
        {
            $this->im = imagecreatefromjpeg($this->srcimg);
        }
        if($this->type=="gif")
        {
            $this->im = imagecreatefromgif($this->srcimg);
        }
        if($this->type=="png")
        {
            $this->im = imagecreatefrompng($this->srcimg);
        }
    }
    //图象目标地址
    function dst_img($dstpath)
    {
        $full_length  = strlen($this->srcimg);

        $type_length  = strlen($this->type);
        $name_length  = $full_length-$type_length;

        $name         = substr($this->srcimg,0,$name_length-1);
        $this->dstimg = $dstpath;

//echo $this->dstimg;
    }
}
?>

类的调用方法

$resizeimage = new resizeimage("图片源文件地址", "200", "100", "0","缩略图地址");

<?php
error_reporting( E_ALL );

// 测试
imagezoom('1.jpg', '2.jpg', 400, 300, '#FFFFFF');

/*
    php缩略图函数：
        等比例无损压缩，可填充补充色 author: 华仔
    主持格式：
        bmp 、jpg 、gif、png
    param:
        @srcimage : 要缩小的图片
        @dstimage : 要保存的图片
        @dst_width: 缩小宽
        @dst_height: 缩小高
        @backgroundcolor: 补充色  如：#FFFFFF  支持 6位  不支持3位
*/
function imagezoom( $srcimage, $dstimage,  $dst_width, $dst_height, $backgroundcolor ) {
       
        // 中文件名乱码
        if ( PHP_OS == 'WINNT' ) {
                $srcimage = iconv('UTF-8', 'GBK', $srcimage);
                $dstimage = iconv('UTF-8', 'GBK', $dstimage);
        }
   
    $dstimg = imagecreatetruecolor( $dst_width, $dst_height );
    $color = imagecolorallocate($dstimg
        , hexdec(substr($backgroundcolor, 1, 2))
        , hexdec(substr($backgroundcolor, 3, 2))
        , hexdec(substr($backgroundcolor, 5, 2))
    );
    imagefill($dstimg, 0, 0, $color);
   
    if ( !$arr=getimagesize($srcimage) ) {
                echo "要生成缩略图的文件不存在";
                exit;
        }
       
    $src_width = $arr[0];
    $src_height = $arr[1];
    $srcimg = null;
    $method = getcreatemethod( $srcimage );
    if ( $method ) {
        eval( '$srcimg = ' . $method . ';' );
    }
   
    $dst_x = 0;
    $dst_y = 0;
    $dst_w = $dst_width;
    $dst_h = $dst_height;
    if ( ($dst_width / $dst_height - $src_width / $src_height) > 0 ) {
        $dst_w = $src_width * ( $dst_height / $src_height );
        $dst_x = ( $dst_width - $dst_w ) / 2;
    } elseif ( ($dst_width / $dst_height - $src_width / $src_height) < 0 ) {
        $dst_h = $src_height * ( $dst_width / $src_width );
        $dst_y = ( $dst_height - $dst_h ) / 2;
    }

    imagecopyresampled($dstimg, $srcimg, $dst_x
        , $dst_y, 0, 0, $dst_w, $dst_h, $src_width, $src_height);
   
    // 保存格式
    $arr = array(
        'jpg' => 'imagejpeg'
        , 'jpeg' => 'imagejpeg'
        , 'png' => 'imagepng'
        , 'gif' => 'imagegif'
        , 'bmp' => 'imagebmp'
    );
    $suffix = strtolower( array_pop(explode('.', $dstimage ) ) );
    if (!in_array($suffix, array_keys($arr)) ) {
        echo "保存的文件名错误";
        exit;
    } else {
        eval( $arr[$suffix] . '($dstimg, "'.$dstimage.'");' );
    }
   
    imagejpeg($dstimg, $dstimage);
   
    imagedestroy($dstimg);
    imagedestroy($srcimg);
   
}

function getcreatemethod( $file ) {
        $arr = array(
                '474946' => "imagecreatefromgif('$file')"
                , 'FFD8FF' => "imagecreatefromjpeg('$file')"
                , '424D' => "imagecreatefrombmp('$file')"
                , '89504E' => "imagecreatefrompng('$file')"
        );
        $fd = fopen( $file, "rb" );
        $data = fread( $fd, 3 );
       
        $data = str2hex( $data );
       
        if ( array_key_exists( $data, $arr ) ) {
                return $arr[$data];
        } elseif ( array_key_exists( substr($data, 0, 4), $arr ) ) {
                return $arr[substr($data, 0, 4)];
        } else {
                return false;
        }
}

function str2hex( $str ) {
        $ret = "";
       
        for( $i = 0; $i < strlen( $str ) ; $i++ ) {
                $ret .= ord($str[$i]) >= 16 ? strval( dechex( ord($str[$i]) ) )
                        : '0'. strval( dechex( ord($str[$i]) ) );
        }
       
        return strtoupper( $ret );
}

// BMP 创建函数  php本身无
function imagecreatefrombmp($filename)
{
   if (! $f1 = fopen($filename,"rb")) return FALSE;

   $FILE = unpack("vfile_type/Vfile_size/Vreserved/Vbitmap_offset", fread($f1,14));
   if ($FILE['file_type'] != 19778) return FALSE;

   $BMP = unpack('Vheader_size/Vwidth/Vheight/vplanes/vbits_per_pixel'.
                 '/Vcompression/Vsize_bitmap/Vhoriz_resolution'.
                 '/Vvert_resolution/Vcolors_used/Vcolors_important', fread($f1,40));
   $BMP['colors'] = pow(2,$BMP['bits_per_pixel']);
   if ($BMP['size_bitmap'] == 0) $BMP['size_bitmap'] = $FILE['file_size'] - $FILE['bitmap_offset'];
   $BMP['bytes_per_pixel'] = $BMP['bits_per_pixel']/8;
   $BMP['bytes_per_pixel2'] = ceil($BMP['bytes_per_pixel']);
   $BMP['decal'] = ($BMP['width']*$BMP['bytes_per_pixel']/4);
   $BMP['decal'] -= floor($BMP['width']*$BMP['bytes_per_pixel']/4);
   $BMP['decal'] = 4-(4*$BMP['decal']);
   if ($BMP['decal'] == 4) $BMP['decal'] = 0;
  
   $PALETTE = array();
   if ($BMP['colors'] < 16777216)
   {
    $PALETTE = unpack('V'.$BMP['colors'], fread($f1,$BMP['colors']*4));
   }
  
   $IMG = fread($f1,$BMP['size_bitmap']);
   $VIDE = chr(0);

   $res = imagecreatetruecolor($BMP['width'],$BMP['height']);
   $P = 0;
   $Y = $BMP['height']-1;
   while ($Y >= 0)
   {
        $X=0;
        while ($X < $BMP['width'])
        {
         if ($BMP['bits_per_pixel'] == 24)
            $COLOR = unpack("V",substr($IMG,$P,3).$VIDE);
         elseif ($BMP['bits_per_pixel'] == 16)
         { 
            $COLOR = unpack("n",substr($IMG,$P,2));
            $COLOR[1] = $PALETTE[$COLOR[1]+1];
         }
         elseif ($BMP['bits_per_pixel'] == 8)
         { 
            $COLOR = unpack("n",$VIDE.substr($IMG,$P,1));
            $COLOR[1] = $PALETTE[$COLOR[1]+1];
         }
         elseif ($BMP['bits_per_pixel'] == 4)
         {
            $COLOR = unpack("n",$VIDE.substr($IMG,floor($P),1));
            if (($P*2)%2 == 0) $COLOR[1] = ($COLOR[1] >> 4) ; else $COLOR[1] = ($COLOR[1] & 0x0F);
            $COLOR[1] = $PALETTE[$COLOR[1]+1];
         }
         elseif ($BMP['bits_per_pixel'] == 1)
         {
            $COLOR = unpack("n",$VIDE.substr($IMG,floor($P),1));
            if     (($P*8)%8 == 0) $COLOR[1] =  $COLOR[1]        >>7;
            elseif (($P*8)%8 == 1) $COLOR[1] = ($COLOR[1] & 0x40)>>6;
            elseif (($P*8)%8 == 2) $COLOR[1] = ($COLOR[1] & 0x20)>>5;
            elseif (($P*8)%8 == 3) $COLOR[1] = ($COLOR[1] & 0x10)>>4;
            elseif (($P*8)%8 == 4) $COLOR[1] = ($COLOR[1] & 0x8)>>3;
            elseif (($P*8)%8 == 5) $COLOR[1] = ($COLOR[1] & 0x4)>>2;
            elseif (($P*8)%8 == 6) $COLOR[1] = ($COLOR[1] & 0x2)>>1;
            elseif (($P*8)%8 == 7) $COLOR[1] = ($COLOR[1] & 0x1);
            $COLOR[1] = $PALETTE[$COLOR[1]+1];
         }
         else
            return FALSE;
         imagesetpixel($res,$X,$Y,$COLOR[1]);
         $X++;
         $P += $BMP['bytes_per_pixel'];
        }
        $Y--;
        $P+=$BMP['decal'];
   }
   fclose($f1);

return $res;
}
// BMP 保存函数，php本身无
function imagebmp ($im, $fn = false)
{
    if (!$im) return false;
           
    if ($fn === false) $fn = 'php://output';
    $f = fopen ($fn, "w");
    if (!$f) return false;
           
    $biWidth = imagesx ($im);
    $biHeight = imagesy ($im);
    $biBPLine = $biWidth * 3;
    $biStride = ($biBPLine + 3) & ~3;
    $biSizeImage = $biStride * $biHeight;
    $bfOffBits = 54;
    $bfSize = $bfOffBits + $biSizeImage;
           
    fwrite ($f, 'BM', 2);
    fwrite ($f, pack ('VvvV', $bfSize, 0, 0, $bfOffBits));
           
    fwrite ($f, pack ('VVVvvVVVVVV', 40, $biWidth, $biHeight, 1, 24, 0, $biSizeImage, 0, 0, 0, 0));
           
    $numpad = $biStride - $biBPLine;
    for ($y = $biHeight - 1; $y >= 0; --$y)
    {
        for ($x = 0; $x < $biWidth; ++$x)
        {
            $col = imagecolorat ($im, $x, $y);
            fwrite ($f, pack ('V', $col), 3);
        }
        for ($i = 0; $i < $numpad; ++$i)
            fwrite ($f, pack ('C', 0));
    }
    fclose ($f);
    return true;
}

?>

<?php
function _UPLOADPIC($upfile, $maxsize, $updir, $newname = 'date') {

if ($newname == 'date')

$newname = date ( "Ymdhis" ); //使用日期做文件名 

$name = $upfile ["name"];

$type = $upfile ["type"];

$size = $upfile ["size"];

$tmp_name = $upfile ["tmp_name"];

switch ($type) {

case 'image/pjpeg' :

case 'image/jpeg' :

$extend = ".jpg";

break;

case 'image/gif' :

$extend = ".gif";

break;

case 'image/png' :

$extend = ".png";

break;

}

if (emptyempty ( $extend )) {

echo ( "警告！只能上传图片类型：GIF JPG PNG" );

exit ();

}

if ($size > $maxsize) {

$maxpr = $maxsize / 1000;

echo ( "警告！上传图片大小不能超过" . $maxpr . "K!" );

exit ();

}

if (move_uploaded_file ( $tmp_name, $updir . $newname . $extend )) {

return $updir . $newname . $extend;

}

}

function show_pic_scal($width, $height, $picpath) {

$imginfo = GetImageSize ( $picpath );

$imgw = $imginfo [0];

$imgh = $imginfo [1];

$ra = number_format ( ($imgw / $imgh), 1 ); //宽高比

$ra2 = number_format ( ($imgh / $imgw), 1 ); //高宽比

if ($imgw > $width or $imgh > $height) {

if ($imgw > $imgh) {

$newWidth = $width;

$newHeight = round ( $newWidth / $ra );

} elseif ($imgw < $imgh) {

$newHeight = $height;

$newWidth = round ( $newHeight / $ra2 );

} else {

$newWidth = $width;

$newHeight = round ( $newWidth / $ra );

}

} else {

$newHeight = $imgh;

$newWidth = $imgw;

}

$newsize [0] = $newWidth;

$newsize [1] = $newHeight;

return $newsize;

}

function getImageInfo($src)

{

return getimagesize($src);

}

/**

* 创建图片，返回资源类型

* @param string $src 图片路径

* @return resource $im 返回资源类型 

* **/ 

function create($src)

{

$info=getImageInfo($src);

switch ($info[2])

{

case 1:

$im=imagecreatefromgif($src);

break;

case 2:

$im=imagecreatefromjpeg($src);

break;

case 3:

$im=imagecreatefrompng($src);

break;

}

return $im;

}

/**

* 缩略图主函数

* @param string $src 图片路径

* @param int $w 缩略图宽度

* @param int $h 缩略图高度

* @return mixed 返回缩略图路径

* **/ 

function resize($src,$w,$h)

{

$temp=pathinfo($src);

$name=$temp["basename"];//文件名

$dir=$temp["dirname"];//文件所在的文件夹

$extension=$temp["extension"];//文件扩展名

$savepath="{$dir}/{$name}";//缩略图保存路径,新的文件名为*.thumb.jpg

//获取图片的基本信息

$info=getImageInfo($src);

$width=$info[0];//获取图片宽度

$height=$info[1];//获取图片高度

$per1=round($width/$height,2);//计算原图长宽比

$per2=round($w/$h,2);//计算缩略图长宽比

//计算缩放比例

if($per1>$per2||$per1==$per2)

{

//原图长宽比大于或者等于缩略图长宽比，则按照宽度优先

$per=$w/$width;

}

if($per1<$per2)

{

//原图长宽比小于缩略图长宽比，则按照高度优先

$per=$h/$height;

}

$temp_w=intval($width*$per);//计算原图缩放后的宽度

$temp_h=intval($height*$per);//计算原图缩放后的高度

$temp_img=imagecreatetruecolor($temp_w,$temp_h);//创建画布

$im=create($src);

imagecopyresampled($temp_img,$im,0,0,0,0,$temp_w,$temp_h,$width,$height);

if($per1>$per2)

{

imagejpeg($temp_img,$savepath, 100);

imagedestroy($im);

return addBg($savepath,$w,$h,"w");

//宽度优先，在缩放之后高度不足的情况下补上背景

}

if($per1==$per2)

{

imagejpeg($temp_img,$savepath, 100);

imagedestroy($im);

return $savepath;

//等比缩放

}

if($per1<$per2)

{

imagejpeg($temp_img,$savepath, 100);

imagedestroy($im);

return addBg($savepath,$w,$h,"h");

//高度优先，在缩放之后宽度不足的情况下补上背景

}

}

/**

* 添加背景

* @param string $src 图片路径

* @param int $w 背景图像宽度

* @param int $h 背景图像高度

* @param String $first 决定图像最终位置的，w 宽度优先 h 高度优先 wh:等比

* @return 返回加上背景的图片

* **/ 

function addBg($src,$w,$h,$fisrt="w")

{

$bg=imagecreatetruecolor($w,$h);

$white = imagecolorallocate($bg,255,255,255);

imagefill($bg,0,0,$white);//填充背景

//获取目标图片信息

$info=getImageInfo($src);

$width=$info[0];//目标图片宽度

$height=$info[1];//目标图片高度

$img=create($src);

if($fisrt=="wh")

{

//等比缩放

return $src;

}

else 

{

if($fisrt=="w")

{

$x=0;

$y=($h-$height)/2;//垂直居中

}

if($fisrt=="h")

{

$x=($w-$width)/2;//水平居中

$y=0;

}

imagecopymerge($bg,$img,$x,$y,0,0,$width,$height,100);

imagejpeg($bg,$src,100);

imagedestroy($bg);

imagedestroy($img);

return $src;

}
}
?> 

使用方法： 

$filename=(_UPLOADPIC($_FILES["upload"],$maxsize,$updir,$newname='date'));
$show_pic_scal=show_pic_scal(230, 230, $filename);
resize($filename,$show_pic_scal[0],$show_pic_scal[1]);

<?php
/**
 * 调用示例
 * */
session_start();
$randCode = '';
$chars = 'abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPRSTUVWXYZ23456789';
for ( $i = 0; $i < 4; $i++ )
{
 $randCode .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
}
$_SESSION['code'] = strtoupper($randCode);   // 记录session
ImageCode($randCode, 60);    // 显示GIF动画

/**
 * ImageCode 生成GIF图片验证
 * @param $string 字符串
 * @param $width 宽度
 * @param $height 高度
 * */
function ImageCode($string = '', $width = 75, $height = 25)
{
 $authstr = $string ? $string : ((time() % 2 == 0) ? mt_rand(1000, 9999) : mt_rand(10000, 99999));
 
 $board_width = $width;
 $board_height = $height;
 // 生成一个32帧的GIF动画
 for($i = 0; $i < 32; $i++)
 {
  ob_start();
     $image = imagecreate($board_width, $board_height);
     imagecolorallocate($image, 0,0,0);
     // 设定文字颜色数组
   $colorList[] = ImageColorAllocate($image, 15,73,210);
   $colorList[] = ImageColorAllocate($image, 0,64,0);
   $colorList[] = ImageColorAllocate($image, 0,0,64);
   $colorList[] = ImageColorAllocate($image, 0,128,128);
   $colorList[] = ImageColorAllocate($image, 27,52,47);
   $colorList[] = ImageColorAllocate($image, 51,0,102);
   $colorList[] = ImageColorAllocate($image, 0,0,145);
   $colorList[] = ImageColorAllocate($image, 0,0,113);
   $colorList[] = ImageColorAllocate($image, 0,51,51);
   $colorList[] = ImageColorAllocate($image, 158,180,35);
   $colorList[] = ImageColorAllocate($image, 59,59,59);
   $colorList[] = ImageColorAllocate($image, 0,0,0);
   $colorList[] = ImageColorAllocate($image, 1,128,180);
   $colorList[] = ImageColorAllocate($image, 0,153,51);
   $colorList[] = ImageColorAllocate($image, 60,131,1);
   $colorList[] = ImageColorAllocate($image, 0,0,0);
   $fontcolor = ImageColorAllocate($image, 0,0,0);
   $gray = ImageColorAllocate($image, 245,245,245);
   
     $color = imagecolorallocate($image, 255,255,255);
     $color2 = imagecolorallocate($image, 255,0,0);
    
     imagefill($image, 0, 0, $gray);
    
     $space = 15;  // 字符间距
     if($i > 0)   // 屏蔽第一帧
     {
      for ($k = 0; $k < strlen($authstr); $k++)
      {
    $colorRandom = mt_rand(0,sizeof($colorList)-1);
    $float_top = rand(0,4);
    $float_left = rand(0,3);
    imagestring($image, 6, $space * $k, $top + $float_top, substr($authstr, $k, 1), $colorList[$colorRandom]);
   }
     }
    
  for ($k = 0; $k < 20; $k++)
  {
   $colorRandom = mt_rand(0,sizeof($colorList)-1);
    imagesetpixel($image, rand()%70 , rand()%15 , $colorList[$colorRandom]);
 
  }
  // 添加干扰线
  for($k = 0; $k < 3; $k++)
  {
   $colorRandom = mt_rand(0, sizeof($colorList)-1);
   // $todrawline = rand(0,1);
   $todrawline = 1;
   if($todrawline)
   {
    imageline($image, mt_rand(0, $board_width), mt_rand(0,$board_height), mt_rand(0,$board_width), mt_rand(0,$board_height), $colorList[$colorRandom]);
   }
   else
   {
    $w = mt_rand(0,$board_width);
    $h = mt_rand(0,$board_width);
    imagearc($image, $board_width - floor($w / 2) , floor($h / 2), $w, $h,  rand(90,180), rand(180,270), $colorList[$colorRandom]);
   }
  }
     imagegif($image);
     imagedestroy($image);
     $imagedata[] = ob_get_contents();
     ob_clean(); 
     ++$i; 
 }
 
 $gif = new GIFEncoder($imagedata); 
 Header ('Content-type:image/gif'); 
 echo $gif->GetAnimation(); 
}

/**
 * GIFEncoder类
 * */
Class GIFEncoder
{
    var $GIF = "GIF89a";                /* GIF header 6 bytes        */ 
    var $VER = "GIFEncoder V2.06";        /* Encoder version             */ 

    var $BUF = Array ( ); 
    var $LOP =  0; 
    var $DIS =  2; 
    var $COL = -1; 
    var $IMG = -1; 

    var $ERR = Array ( 
        'ERR00' =>"Does not supported function for only one image!", 
        'ERR01' =>"Source is not a GIF image!", 
        'ERR02' =>"Unintelligible flag ", 
        'ERR03' =>"Could not make animation from animated GIF source", 
    ); 
   
    function GIFEncoder ($GIF_src, $GIF_dly = 100, $GIF_lop = 0, $GIF_dis = 0,  $GIF_red = 0, $GIF_grn = 0, $GIF_blu = 0, $GIF_mod = 'bin' )
    { 
        if (!is_array($GIF_src) && !is_array($GIF_tim))
        { 
            printf ( "%s: %s", $this->VER, $this->ERR['ERR00']); 
            exit( 0 );
        } 
        $this->LOP = ($GIF_lop > -1) ? $GIF_lop : 0; 
        $this->DIS = ($GIF_dis > -1) ? (( $GIF_dis < 3 ) ? $GIF_dis : 3) : 2; 
        $this->COL = ($GIF_red > -1 && $GIF_grn > -1 && $GIF_blu > -1) ? ($GIF_red | ($GIF_grn << 8) | ($GIF_blu << 16)) : -1; 

        for ($i = 0, $src_count = count($GIF_src); $i < $src_count; $i++ )
        {
            if (strToLower( $GIF_mod ) == "url")
            { 
             $this->BUF[] = fread (fopen($GIF_src [$i], "rb"), filesize ($GIF_src [$i])); 
            } 
            elseif(strToLower($GIF_mod) == "bin")
            { 
                $this->BUF [ ] = $GIF_src [ $i ]; 
            } 
            else
            { 
                printf("%s: %s ( %s )!", $this->VER, $this->ERR [ 'ERR02' ], $GIF_mod); 
                exit(0); 
            } 
            if (substr($this->BUF[$i], 0, 6) != "GIF87a" && substr($this->BUF [$i], 0, 6) != "GIF89a")
            { 
                printf( "%s: %d %s", $this->VER, $i, $this->ERR ['ERR01']); 
                exit(0); 
            } 
            for ($j = (13 + 3 * (2 << (ord($this->BUF[$i]{10}) & 0x07 ))), $k = TRUE; $k; $j++)
            { 
                switch ($this->BUF [$i]{$j})
                { 
                    case "!": 
                        if ((substr($this->BUF[$i], ($j + 3), 8)) == "NETSCAPE")
                        { 
                                printf( "%s: %s ( %s source )!", $this->VER, $this->ERR ['ERR03'], ($i + 1)); 
                                exit( 0 ); 
                        } 
                        break; 
                    case ";": 
                        $k = FALSE; 
                        break; 
                } 
            } 
        } 
        GIFEncoder::GIFAddHeader(); 
        for($i = 0, $count_buf = count($this->BUF); $i < $count_buf; $i++)
        { 
         GIFEncoder::GIFAddFrames($i, $GIF_dly[$i]); 
        } 
        GIFEncoder::GIFAddFooter(); 
    } 
   
    function GIFAddHeader ( )
    { 
  $cmap = 0; 
  
  if (ord($this->BUF[0]{10}) & 0x80 )
  { 
   $cmap = 3 * ( 2 << ( ord ( $this->BUF [ 0 ]{10} ) & 0x07 )); 
   
   $this->GIF .= substr ( $this->BUF [ 0 ], 6, 7); 
   $this->GIF .= substr ( $this->BUF [ 0 ], 13, $cmap); 
   $this->GIF .= "!37713NETSCAPE2.031" . GIFEncoder::GIFWord ( $this->LOP ) . ""; 
  } 
    } 
   
    function GIFAddFrames ( $i, $d )
    { 

        $Locals_str = 13 + 3 * (2 <<(ord($this->BUF[$i]{10}) & 0x07)); 

        $Locals_end = strlen($this->BUF[$i]) - $Locals_str - 1; 
        $Locals_tmp = substr ($this->BUF[$i], $Locals_str, $Locals_end); 

        $Global_len = 2 << (ord( $this->BUF [0]{10} ) & 0x07 ); 
        $Locals_len = 2 << (ord( $this->BUF[$i]{10}) & 0x07); 

        $Global_rgb = substr($this->BUF[0], 13, 3 * (2 << ( ord ( $this->BUF[0]{10} ) & 0x07))); 
        $Locals_rgb = substr ( $this->BUF[$i], 13, 3 * (2 << ( ord ( $this->BUF[$i]{10} ) & 0x07))); 

        $Locals_ext = "!xF9x04" . chr(($this->DIS << 2) + 0) . chr(($d >> 0) & 0xFF) . chr(($d >> 8) & 0xFF) . "x0x0"; 

        if ( $this->COL > -1 && ord($this->BUF[$i]{10}) & 0x80)
        { 
            for($j = 0; $j < (2 << (ord( $this->BUF[$i]{10}) & 0x07)); $j++ )
            { 
                if(ord ($Locals_rgb{3 * $j + 0}) == ($this->COL >>  0) & 0xFF && ord ( $Locals_rgb { 3 * $j + 1 } ) == ( $this->COL >>  8 ) & 0xFF && ord ( $Locals_rgb { 3 * $j + 2 } ) == ( $this->COL >> 16 ) & 0xFF )
                { 
                    $Locals_ext = "!xF9x04" . chr(($this->DIS << 2) + 1) . chr (( $d >> 0) & 0xFF) . chr (( $d >> 8) & 0xFF) . chr ($j) . "x0"; 
                    break; 
                } 
            } 
        } 
        switch ( $Locals_tmp { 0 } )
        { 
            case "!": 
                $Locals_img = substr($Locals_tmp, 8, 10); 
                $Locals_tmp = substr($Locals_tmp, 18, strlen ($Locals_tmp) - 18); 
                break; 
            case ",": 
                $Locals_img = substr($Locals_tmp, 0, 10); 
                $Locals_tmp = substr($Locals_tmp, 10, strlen($Locals_tmp) - 10); 
                break; 
        } 
        if ( ord ( $this->BUF[$i]{10} ) & 0x80 && $this->IMG > -1 )
        { 
            if ( $Global_len == $Locals_len )
            { 
    if ( GIFEncoder::GIFBlockCompare ( $Global_rgb, $Locals_rgb, $Global_len ) )
    { 
     $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp ); 
    } 
    else
    { 
     $byte  = ord ( $Locals_img{9}); 
     $byte |= 0x80; 
     $byte &= 0xF8; 
     $byte |= ( ord ( $this->BUF [ 0 ]{10}) & 0x07); 
     $Locals_img{9} = chr($byte); 
     $this->GIF .= ($Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp); 
    } 
            } 
            else
            { 
                $byte  = ord($Locals_img{9}); 
                $byte |= 0x80; 
                $byte &= 0xF8; 
                $byte |= (ord($this->BUF[$i]{10}) & 0x07); 
                $Locals_img {9} = chr($byte); 
                $this->GIF .= ($Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp); 
            } 
        } 
        else
        { 
            $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp ); 
        } 
        $this->IMG  = 1; 
    } 
   
    function GIFAddFooter ( ) { 
        $this->GIF .= ";"; 
    } 
   
    function GIFBlockCompare ( $GlobalBlock, $LocalBlock, $Len )
    { 
        for ( $i = 0; $i < $Len; $i++ )
        { 
            if($GlobalBlock { 3 * $i + 0 } != $LocalBlock { 3 * $i + 0 } || $GlobalBlock { 3 * $i + 1 } != $LocalBlock { 3 * $i + 1 } || $GlobalBlock { 3 * $i + 2 } != $LocalBlock{3 * $i + 2})
            { 
                return ( 0 ); 
            } 
        } 
        return ( 1 ); 
    } 
   
    function GIFWord ( $int )
    { 
       return ( chr ( $int & 0xFF ) . chr ( ( $int >> 8 ) & 0xFF ) ); 
    } 
   
    function GetAnimation ( )
    { 
        return ($this->GIF); 
    } 
}

 
/**********************
*@filename - path to the image
*@tmpname - temporary path to thumbnail
*@xmax - max width
*@ymax - max height
*/
function resize_image($filename, $tmpname, $xmax, $ymax)
{
    $ext = explode(".", $filename);
    $ext = $ext[count($ext)-1];

    if($ext == "jpg" || $ext == "jpeg")
        $im = imagecreatefromjpeg($tmpname);
    elseif($ext == "png")
        $im = imagecreatefrompng($tmpname);
    elseif($ext == "gif")
        $im = imagecreatefromgif($tmpname);

    $x = imagesx($im);
    $y = imagesy($im);

    if($x <= $xmax && $y <= $ymax)
        return $im;

    if($x >= $y) {
        $newx = $xmax;
        $newy = $newx * $y / $x;
    }
    else {
        $newy = $ymax;
        $newx = $x / $y * $newy;
    }

    $im2 = imagecreatetruecolor($newx, $newy);
    imagecopyresized($im2, $im, 0, 0, 0, 0, floor($newx), floor($newy), $x, $y);
    return $im2;
}

function creat_thumbnail($img,$w,$h,$path)
{
 $org_info = getimagesize($img); //获得图像大小且是通过post传递过来的
 //var_dump($org_info);
 //Array ( [0] => 1024 [1] => 768 [2] => 3 [3] => width="1024" height="768" [bits] => 8 [mime] => image/png )
 $orig_x = $org_info[0]; //图像宽度
 $orig_y = $org_info[1]; //图像高度
 $orig_type = $org_info[2]; //图片类别即后缀 1 = GIF，2 = JPG，3 = PNG，

 //是真彩色图像
 if (function_exists("imagecreatetruecolor"))
 {
  switch($orig_type)
  {
   //从给定的gif文件名中取得的图像
   case 1  : $thumb_type = ".gif"; $_creatImage = "imagegif"; $_function = "imagecreatefromgif";
   break;
   //从给定的jpeg,jpg文件名中取得的图像
   case 2  : $thumb_type = ".jpg"; $_creatImage = "imagejpeg"; $_function = "imagecreatefromjpeg";
   break;
   //从给定的png文件名中取得的图像
   case 3  : $thumb_type = ".png"; $_creatImage = "imagepng"; $_function = "imagecreatefrompng";
   break;
  }
 }
 //如果从给定的文件名可取得的图像
 if(function_exists($_function))
 {
  $orig_image = $_function($img); //从给定的$img文件名中取得的图像
 }
 if (($orig_x / $orig_y) >= (4 / 3)) //如果宽/高 >= 4/3
 {
  $y = round($orig_y / ($orig_x / $w)); //对浮点数进行四舍五入
  $x = $w;
 }
 else //即 高/宽 >= 4/3
 {
  $x = round($orig_x / ($orig_y / $h));
  $y = $h;
 }
 $sm_image = imagecreatetruecolor($x, $y); //创建真彩色图片
 //重采样拷贝部分图像并调整大小
 Imagecopyresampled($sm_image, $orig_image, 0, 0, 0, 0, $x, $y, $orig_x, $orig_y);
 //imageJPEG($sm_image, '', 80); //在浏览器输出图像
 $tnpath = $path."/"."s_".date('YmdHis').$thumb_type; //缩略图的路径
 $thumbnail = @$_creatImage($sm_image, $tnpath, 80); //生成图片,成功返回true(或1)
 imagedestroy ($sm_image); //销毁图像
 if($thumbnail==true)
 {
  return $tnpath;
 }
}