<?

    class SecurityImage
    {
        var $sFont = '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';
        
        var $iWidth;
        var $iHeight;
        var $iNumChars;
        var $sCompiledFont;
        var $bBlur;
        var $bPixels;
        var $sCode;
        
        var $oImage;

        function SecurityImage($iWidth = 150, $iHeight = 30, $iNumChars = 5, $iNumLines = 30)
        {
            $this->iWidth = 10 + ($iNumChars << 4);
            $this->iHeight = 21;
            $this->iNumChars = $iNumChars;

            for ($i = 0, $zz = 0; $i < strlen($this->sFont) >> 2; $i++)
            {
                $r = hexdec($this->sFont[$zz++] . $this->sFont[$zz++]);
                $c = hexdec($this->sFont[$zz++] . $this->sFont[$zz++]);
                
                for ($z = 0; $z < $r; $z++)
                    $this->sCompiledFont .= chr($c);
            }
            
            $this->bBlur = false;
            $this->bPixels = false;
            
            for ($i = 0; $i < $this->iNumChars; $i++)
                $this->sCode .= rand(0, 9);
        }
    
        function PutNumber($image, $number, $color, $x, $y)
        {
            for ($yy = 0; $yy < 16; $yy++)
                for ($xx = 0; $xx < 14; $xx++)
                    if ($this->sCompiledFont[($number * 14) + $xx + (($yy >> 1) * 140)] == 'x')
                        $this->oImage[$x + $xx + (($y + $yy) * $this->iWidth)] = $color;
        }
        
        function GetPixel($x, $y)
        {
            if ($y >= 0 && $y <= $this->iHeight)
                if ($x >= 0 && $x <= $this->iWidth)
                    return $this->oImage[$x + ($y * $this->iWidth)];
            
            return 63;
        }
        
        function BlurImage($image)
        {
            $z = 0;
            
            for ($y = 0; $y < $this->iHeight; $y++)
            {
                for ($x = 0; $x < $this->iWidth; $x++)
                {
                    $b = $this->bBlur ? rand(0, 1) : 0;
                    
                    $c = $this->GetPixel($x - $b,   $y - 1);
                    $c += $this->GetPixel($x,       $y - 1);
                    $c += $this->GetPixel($x + $b,  $y - 1);

                    $c += $this->GetPixel($x - $b,  $y);
                    $c += $this->GetPixel($x,       $y);
                    $c += $this->GetPixel($x + $b,  $y);

                    $c += $this->GetPixel($x - $b,  $y+$b);
                    $c += $this->GetPixel($x,       $y+$b);
                    $c += $this->GetPixel($x + $b,  $y+$b);
                    
                    $c /= 9;
                    
                    $this->oImage[$z++] = $c;
                }
            }
        }
        
        function Create($sFilename = '')
        {
            $image = imagecreate($this->iWidth, $this->iHeight);
            
            for ($i = 0; $i < 64; $i++)
                imagecolorallocate($image, $i << 2, $i << 2, $i << 2);
            
            for ($y = 0; $y <= $this->iHeight; $y++)
                for ($x = 0; $x <= $this->iWidth; $x++)
                    $this->oImage[$x + ($y * $this->iWidth)] = 64;
            
            for ($i = 0; $i < strlen($this->sCode); $i++)
                $this->PutNumber($image, $this->sCode[$i], rand(16, 32), 5 + ($i << 4), 2);
            
            if ($this->bPixels)
                for ($i = 0; $i < 256; $i++)
                    $this->oImage[rand(0, $this->iWidth * $this->iHeight)] = 0;
            
            $this->BlurImage($image);
            
            for ($z = 0, $y = 0; $y < $this->iHeight; $y++)
                for($x = 0; $x < $this->iWidth; $x++)
                    imagesetpixel($image, $x, $y, $this->oImage[$z++]);
            
            if (empty($sFileName))
            {
                header("Content-type: image/png");
                imagepng($image);
            }
            else
                imagepng($image, $sFileName);
            
            return true;
        }
        
        function GetCode()
        {
            return $this->sCode;
        }
    }

?>