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
PHP中的超全局变量
Oct 09 PHP
PHP正确配置mysql(apache环境)
Aug 28 PHP
PHP 读取大文件的X行到Y行内容的实现代码
Jun 24 PHP
如何使用PHP实现javascript的escape和unescape函数
Jun 29 PHP
浅析php中如何在有限的内存中读取大文件
Jul 02 PHP
PHP常用的缓存技术汇总
May 05 PHP
PHP模拟asp.net的StringBuilder类实现方法
Aug 08 PHP
摘自织梦CMS中的图片处理类
Aug 08 PHP
php对文件夹进行相关操作(遍历、计算大小)
Nov 04 PHP
PHP 等比例缩放图片详解及实例代码
Sep 18 PHP
Zend Framework上传文件重命名的实现方法
Nov 25 PHP
PHP迭代与递归实现无限级分类
Aug 28 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
《雄兵连》《烈阳天道》真的来了
2020/07/13 国漫
PHP高手需要要掌握的知识点
2014/08/21 PHP
PHP中的替代语法介绍
2015/01/09 PHP
ThinkPHP5 验证器的具体使用
2018/05/31 PHP
PHP实现负载均衡session共享redis缓存操作示例
2018/08/22 PHP
PHP实现cookie跨域session共享的方法分析
2019/08/23 PHP
jQuery中filter(),not(),split()使用方法
2010/07/06 Javascript
动态创建样式表在各浏览器中的差异测试代码
2011/09/13 Javascript
jqgrid 表格数据导出实例
2013/11/21 Javascript
Jquery Ajax xmlhttp请求成功问题
2015/02/04 Javascript
javascript获取wx.config内部字段解决微信分享
2016/03/09 Javascript
jQuery、layer实现弹出层的打开、关闭功能
2017/06/28 jQuery
JavaScript定时器setTimeout()和setInterval()详解
2017/08/18 Javascript
微信小程序实现的3d轮播图效果示例【基于swiper组件】
2018/12/11 Javascript
[00:43]魔廷新尊——痛苦女王至宝捆绑包
2020/06/12 DOTA
Django中URLconf和include()的协同工作方法
2015/07/20 Python
浅谈终端直接执行py文件,不需要python命令
2017/01/23 Python
Python numpy 提取矩阵的某一行或某一列的实例
2018/04/03 Python
解决Python3中的中文字符编码的问题
2018/07/18 Python
Python之pymysql的使用小结
2019/07/01 Python
详解Python Qt的窗体开发的基本操作
2019/07/14 Python
pyCharm 设置调试输出窗口中文显示方式(字符码转换)
2020/06/09 Python
python两种注释用法的示例
2020/10/09 Python
Python getsizeof()和getsize()区分详解
2020/11/20 Python
详解使用postMessage解决iframe跨域通信问题
2019/11/01 HTML / CSS
竞选体育委员演讲稿
2014/04/26 职场文书
求职信模板
2014/05/23 职场文书
升国旗演讲稿
2014/09/05 职场文书
小学校园广播稿(3篇)
2014/09/19 职场文书
党的群众路线教育实践活动对照检查材料(四风)
2014/09/27 职场文书
学生检讨书
2015/01/27 职场文书
教师读书活动心得体会
2016/01/14 职场文书
nginx 防盗链防爬虫配置详解
2021/03/31 Servers
Python办公自动化之教你如何用Python将任意文件转为PDF格式
2021/06/28 Python
SpringBoot整合Mybatis Generator自动生成代码
2021/08/23 Java/Android
vue中 this.$set的使用详解
2021/11/17 Vue.js