一款php按比例生成缩略图代码

function resizeimage($image,$width,$height,$scale) {
 list($imagewidth, $imageheight, $imagetype) = getimagesize($image);
 $imagetype = image_type_to_mime_type($imagetype);
 $newimagewidth = ceil($width * $scale);
 $newimageheight = ceil($height * $scale);
 $newimage = imagecreatetruecolor($newimagewidth,$newimageheight);
 switch($imagetype) {
  case "image/gif":
   $source=imagecreatefromgif($image);
   break;
     case "image/pjpeg":
  case "image/jpeg":
  case "image/jpg":
   $source=imagecreatefromjpeg($image);
   break;
     case "image/png":
  case "image/x-png":
   $source=imagecreatefrompng($image);
   break;
   }
 imagecopyresampled($newimage,$source,0,0,0,0,$newimagewidth,$newimageheight,$width,$height);
 
 switch($imagetype) {
  case "image/gif":
     imagegif($newimage,$image);
   break;
       case "image/pjpeg":
  case "image/jpeg":
  case "image/jpg":
     imagejpeg($newimage,$image,90);
   break;
  case "image/png":
  case "image/x-png":
   imagepng($newimage,$image); 
   break;
    }
 
 chmod($image, 0777);
 return $image;
}
?>

<?php
header("content-type:image/jpeg");
$filename = hsdir.'/mljntc2p.jpg';
$im = imagecreatefromjpeg($filename);
$h=imagesy($im);//获得目标图片高度
$new_img_width  = 257;
$new_img_height = 522;

$newim = imagecreate($new_img_width, $new_img_height);
$white = imagecolorallocate($newim, 255,255,255); //设置背景颜色
imagecopyresized($newim, $im, 0, 0, 0, 0, $new_img_width, $new_img_height, $new_img_width, $new_img_height);
imagefilledrectangle($newim,0,$h,$new_img_width,$new_img_height,$white);
//填充  目标图片高度作为起驶y坐标 以指定截取宽高为结束坐标
imagejpeg($newim);
imagedestroy($newim);
imagedestroy($im);
?>

<?php
header("content-type:image/jpeg");
$filename = 'myface.jpg';
$im = imagecreatefromjpeg($filename);
$new_img_width  = 80;
$new_img_height = 150;
$newim = imagecreate($new_img_width, $new_img_height);
$white = imagecolorallocate($newim, 255,255,255); //设置背景颜色
imagecopyresized($newim, $im, 0, 0, 0, 0, $new_img_width, $new_img_height, $new_img_width, $new_img_height);
imagejpeg($newim);
imagedestroy($newim);
imagedestroy($im);
?>

class securecode
{
    private static $instance=null;
    private $code = '';
    private $fontfile;
    private $validate;
    private $image;
    private $specialadd = 'special string for securecode';
    private $codeexpire=86400;
    private $codecookiename='secure_code';

    /**
     * 构造方法
     */
    private function securecode()
    {
        $this->fontfile = dirname( __file__ ) . '/arial.ttf';
    }

    private function __construct()
    {
        $this->securecode();
    }
   
    public static function getinstance()
    {
        if (self::$instance==null)
            self::$instance=new self();
       
        return self::$instance;
    }

    /**
     * 指定字体文件所在路径，默认为当前文件夹下arial.ttf文件
     * @param $fontfile 文件路径
     * @return void
     */
    function loadfont($fontfile)
    {
        $this->fontfile = $fontfile;
    }

    /**
     * 图片输出方法，在执行本方法前程序不应该有任何形式的输出
     * @return void;
     */
    function stroke()
    {
        $this->savecode();
        self::sendheader();
        imagegif( $this->validate );
        imagedestroy( $this->validate );
        imagedestroy( $this->image );
    }

    /**
     * 图片保存方法
     * @param $filename 保存路径
     * @return void
     */
    function save($filename)
    {
        $this->savecode();
        imagegif( $this->validate , $filename );
        imagedestroy( $this->validate );
        imagedestroy( $this->image );
    }
   
  /**
     * 验证码验证方法
     * @param $input 要验证的字符串，即用户的输入内容
     * @return boolean 验证结果
     */
    function verify($input)
    {
        $input=strtolower($input);
        $targetcode=$this->authcode($input);
        $code=$this->getcookie();
        if (empty($code)||$code!=$targetcode)
            $result= false;
        else
            $result=true;
        $_cookie[$this->codecookiename]='';
        setcookie ( $this->codecookiename, '', - 1 );
        return $result;
    }

    /**
     * 图片创建方法
     * @return void;
     */
    function createimage()
    {
        $this->randcode();
       
        $size = 30;
        $width = 90;
        $height = 35;
        $degrees = array (
            rand( 0 , 30 ), rand( 0 , 30 ), rand( 0 , 30 ), rand( 0 , 30 )
        );
       

        for ($i = 0; $i < 4; ++$i)
        {
            if (rand() % 2);
            else $degrees[$i] = -$degrees[$i];
        }
       
        $this->image = imagecreatetruecolor( $size , $size );
        $this->validate = imagecreatetruecolor( $width , $height );
        $back = imagecolorallocate( $this->image , 255 , 255 , 255 );
        $border = imagecolorallocate( $this->image , 0 , 0 , 0 );
        imagefilledrectangle( $this->validate , 0 , 0 , $width , $height , $back );
       
        for ($i = 0; $i < 4; ++$i)
        {
            $temp = self::rgbtohsv( rand( 0 , 250 ) , rand( 0 , 150 ) , rand( 0 , 250 ) );
           
            if ($temp[2] > 60) $temp[2] = 60;
           
            $temp = self::hsvtorgb( $temp[0] , $temp[1] , $temp[2] );
            $textcolor[$i] = imagecolorallocate( $this->image , $temp[0] , $temp[1] , $temp[2] );
        }
       
        for ($i = 0; $i < 200; ++$i)
        {
            $randpixelcolor = imagecolorallocate( $this->validate , rand( 0 , 255 ) , rand( 0 , 255 ) , rand( 0 , 255 ) );
            imagesetpixel( $this->validate , rand( 1 , 87 ) , rand( 1 , 35 ) , $randpixelcolor );
        }
       
        $temp = self::rgbtohsv( rand( 220 , 255 ) , rand( 220 , 255 ) , rand( 220 , 255 ) );
       
        if ($temp[2] < 200) $temp[2] = 255;
       
        $temp = self::hsvtorgb( $temp[0] , $temp[1] , $temp[2] );
        $randlinecolor = imagecolorallocate( $this->image , $temp[0] , $temp[1] , $temp[2] );
       
        self::imagelinethick( $this->validate , $textcolor[rand( 0 , 3 )] );
       
        imagefilledrectangle( $this->image , 0 , 0 , $size , $size , $back );
        putenv( 'gdfontpath=' . realpath( '.' ) );
       
        // name the font to be used (note the lack of the .ttf extension
        imagettftext( $this->image , 15 , 0 , 8 , 20 , $textcolor[0] , $this->fontfile , $this->code[0] );
       
        $this->image = imagerotate( $this->image , $degrees[0] , $back );
        imagecolortransparent( $this->image , $back );
        imagecopymerge( $this->validate , $this->image , 1 , 4 , 4 , 5 , imagesx( $this->image ) - 10 , imagesy( $this->image ) - 10 , 100 );
       
        $this->image = imagecreatetruecolor( $size , $size );
        imagefilledrectangle( $this->image , 0 , 0 , $size , $size , $back );
        imagettftext( $this->image , 15 , 0 , 8 , 20 , $textcolor[1] , $this->fontfile , $this->code[1] );
        $this->image = imagerotate( $this->image , $degrees[1] , $back );
        imagecolortransparent( $this->image , $back );
        imagecopymerge( $this->validate , $this->image , 21 , 4 , 4 , 5 , imagesx( $this->image ) - 10 , imagesy( $this->image ) - 10 , 100 );
       
        $this->image = imagecreatetruecolor( $size , $size );
        imagefilledrectangle( $this->image , 0 , 0 , $size - 1 , $size - 1 , $back );
        imagettftext( $this->image , 15 , 0 , 8 , 20 , $textcolor[2] , $this->fontfile , $this->code[2] );
        $this->image = imagerotate( $this->image , $degrees[2] , $back );
        imagecolortransparent( $this->image , $back );
        imagecopymerge( $this->validate , $this->image , 41 , 4 , 4 , 5 , imagesx( $this->image ) - 10 , imagesy( $this->image ) - 10 , 100 );
       
        $this->image = imagecreatetruecolor( $size , $size );
        imagefilledrectangle( $this->image , 0 , 0 , $size - 1 , $size - 1 , $back );
        imagettftext( $this->image , 15 , 0 , 8 , 20 , $textcolor[3] , $this->fontfile , $this->code[3] );
        $this->image = imagerotate( $this->image , $degrees[3] , $back );
        imagecolortransparent( $this->image , $back );
        imagecopymerge( $this->validate , $this->image , 61 , 4 , 4 , 5 , imagesx( $this->image ) - 10 , imagesy( $this->image ) - 10 , 100 );
        imagerectangle( $this->validate , 0 , 0 , $width - 1 , $height - 1 , $border );
    }

$img = imagecreate(180,50);

　　$ip = $_server['remote_addr'];

　　imagecolortransparent($img,$bgcolor);

　　$bgcolor = imagecolorallocate($img, 0x2c,0x6d,0xaf); // 背景颜色

　　$shadow = imagecolorallocate($img, 250,0,0); // 阴影颜色

　　$textcolor = imagecolorallocate($img, oxff,oxff,oxff); // 字体颜色

　　imagettftext($img,10,0,78,30,$shadow,"c:/windows/fonts/tahoma.ttf",$ip);

　　//显示背景

　　imagettftext($img,10,0,25,28,$textcolor,"c:/windows/fonts/tahoma.ttf","your ip is".$ip);

　　// 显示ip

　　imagepng($img);

　　imagecreatefrompng($img);

　　imagedestroy($img);