PHP实现GIF图片验证码


Posted in PHP onNovember 04, 2015

这是一个用PHP生成GIF动画来实现动态图片验证码的程序,非常实用,是php用户注册登录界面经常需要用到的验证码程序,有需要GIF动态图片验证码功能的朋友可以收藏一下。
第一步:创建ImageCode.php文件,验证码生成函数代码如下:

<?php
/**
 * 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 .= "!\377\13NETSCAPE2.0\3\1" . GIFEncoder::GIFWord ( $this->LOP ) . "\0"; 
    } 
  } 
  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))); 
    $Locals_ext = "!\xF9\x04" . chr(($this->DIS << 2) + 0) . chr(($d >> 0) & 0xFF) . chr(($d >> 8) & 0xFF) . "\x0\x0"; 
    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 )

        { 
          $Locals_ext = "!\xF9\x04" . chr(($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); 
  } 
}

第二步:验证码生成,创建yzimg.php,并引用入文件ImageCode.php。代码如下:

<?php
if(!isset($_SESSION)){
  session_start();
}
require_once(dirname(__FILE__)."ImageCode.php");
unset($_SESSION['yzm']);
$randCode = '';
$chars = 'abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPRSTUVWXYZ23456789';
for ( $i = 0; $i < 4; $i++ )
{
  $randCode .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
}
$_SESSION['yzm']=$randCode;     // 记录session
ImageCode($randCode, 60);
 
/*方法二*/
/*$authstr = mt_rand(1000, 9999);  // 生成随机字符串
$_SESSION['yzm'] = $authstr;  // 记录session
ImageCode($authstr, 60);  // 显示GIF动画*/
?>

 第三步:调用和显示验证码,在需要添加验证码的页面加入以下代码,代码如下:

<input name="yzm" type="text" class="input1" size="12" style="width:70px;"/>
         <SCRIPT LANGUAGE="JavaScript">
<!--
document.write('<img id="yz_Img" name="imageField" class="yz_Img" title="刷新验证码" onclick="this.src=this.src+Math.random();" src="yzimg.php?'+Math.random()+'">');
//-->
</SCRIPT>

以上就是为大家分享的如何使用php生成动态验证码的相应代码,希望对大家的学习有所帮助。

PHP 相关文章推荐
十天学会php之第九天
Oct 09 PHP
PHP的栏目导航程序
Oct 09 PHP
一个用php3编写的简单计数器
Oct 09 PHP
PHP下操作Linux消息队列完成进程间通信的方法
Jul 24 PHP
php实现在限定区域里自动调整字体大小的类实例
Apr 02 PHP
php图像处理类实例
Jul 28 PHP
微信获取用户地理位置信息的原理与步骤
Nov 12 PHP
详解PHP对象的串行化与反串行化
Jan 24 PHP
Zend Framework实现留言本分页功能(附demo源码下载)
Mar 22 PHP
解决laravel 5.1报错:No supported encrypter found的办法
Jun 07 PHP
PHP基于redis计数器类定义与用法示例
Feb 08 PHP
php array 转json及java 转换 json数据格式操作示例
Nov 13 PHP
php实现分页显示
Nov 03 #PHP
PHP翻页跳转功能实现方法
Nov 30 #PHP
php中注册器模式类用法实例分析
Nov 03 #PHP
php实现zip文件解压操作
Nov 03 #PHP
thinkphp如何获取客户端IP
Nov 03 #PHP
php去除二维数组的重复项方法
Nov 03 #PHP
php在数据库抽象层简单使用PDO的方法
Nov 03 #PHP
You might like
php 禁止页面缓存输出
2009/01/07 PHP
php读取mysql乱码,用set names XXX解决的原理分享
2011/12/29 PHP
ThinkPHP的Widget扩展实例
2014/06/19 PHP
php中解析带中文字符的url函数分享
2015/01/20 PHP
CI框架实现框架前后端分离的方法详解
2016/12/30 PHP
基于jQuery的一个扩展form序列化到json对象
2010/12/09 Javascript
用js写了一个类似php的print_r输出换行功能
2013/02/18 Javascript
node.js中的fs.unlink方法使用说明
2014/12/15 Javascript
Javascript中的方法和匿名方法实例详解
2015/06/13 Javascript
jquery实现搜索框功能实例详解
2018/07/23 jQuery
在Angular中使用JWT认证方法示例
2018/09/10 Javascript
JS调用安卓手机摄像头扫描二维码
2018/10/16 Javascript
初探Vue3.0 中的一大亮点Proxy的使用
2018/12/06 Javascript
微信小程序自定义导航教程(兼容各种手机)
2018/12/12 Javascript
vue实现购物车小案例
2019/09/27 Javascript
springboot+vue+对接支付宝接口+二维码扫描支付功能(沙箱环境)
2020/10/15 Javascript
在vue中给后台接口传的值为数组的格式代码
2020/11/12 Javascript
pygame学习笔记(4):声音控制
2015/04/15 Python
Python首次安装后运行报错(0xc000007b)的解决方法
2016/10/18 Python
Python 处理数据的实例详解
2017/08/10 Python
使用python批量读取word文档并整理关键信息到excel表格的实例
2018/11/07 Python
详解Python用户登录接口的方法
2019/04/17 Python
Tensorflow 使用pb文件保存(恢复)模型计算图和参数实例详解
2020/02/11 Python
Python全面分析系统的时域特性和频率域特性
2020/02/26 Python
Pytorch之Tensor和Numpy之间的转换的实现方法
2020/09/03 Python
日本高岛屋百货购物网站:TAKASHIMAYA
2019/03/24 全球购物
公司年会演讲稿范文
2014/01/11 职场文书
外语专业毕业生自荐信
2014/04/14 职场文书
安全生产标语
2014/06/06 职场文书
文明单位创建材料
2014/12/24 职场文书
青岛导游词
2015/02/12 职场文书
护士辞职信怎么写
2015/02/27 职场文书
道歉信范文
2015/05/12 职场文书
2015年大学生暑期实习报告
2015/07/13 职场文书
运动会加油稿50字
2015/07/21 职场文书
element多个表单校验的实现
2021/05/27 Javascript