PHP实现GIF图片验证码

php  /  管理员 发布于 7年前   172

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：

 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：

 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：

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。

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