关于php验证码的破解。解决方案

$image_name = 'baidu.jpg';
$image = "http://tieba.baidu.com/cgi-bin/genimg?0013286908280168B65F46CEDCD48CF9D46DF47A64587DA42FC48BF1CF8D47BD0D0BC2EE39911C9918D5CF46E79CF94FFA71BC0DC14DAE59197F42F24B4455C205062670A2977101F1A661F7F4716A8BC2C21D586F886CA300E0D42874D6365A1216622D9740163479D1DD416DAE5D70C09EA834F6B9EC307A29CDAF8D0C78FE159402800B113F6039195E5D683695532E4E2FFD8563D732AD19EDFB147B7569B617BDFBE487CE77AE49E75D83BA56B7038971E2081F647A&t=0.7108543934300542";    


$curl = curl_init(); 
curl_setopt($curl, CURLOPT_URL, $image); 
curl_setopt($curl, CURLOPT_REFERER, 'http://tieba.baidu.com/f?kw=baidu'); 
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1); 
$result = curl_exec($curl); 
curl_close($curl); 
file_put_contents($image_name, $result);


$size = getimagesize($image_name);
$im = imagecreatefromjpeg($image_name);
imagejpeg($im, 'baidu.jpg',100);
$width = $size[0];
$height = $size[1];


for($x = 1; $x < $width; $x ++)
{
    for($y = 1; $y < $height; $y ++)
    {
        $color = imagecolorat($im, $x, $y);
        $_col[$x][] = $color;
        if($color < '16777215') $all_color[$color] = $color;
    }
}

$n = array_sum($all_color) / count($all_color);

foreach ($_col as $key=>$val)
{
    foreach ($val as $k=>$v)
        $col[$key] .= $v < $n ? '1':' ';
}

// 去多余行列
foreach ($_col as $key=>$val)
    if(array_sum($val) < 1) unset($col[$key]);


foreach ($col as $key=>$val)
{
    $val = trim($val);
    if(empty($val)) unset($col[$key]);
}

echo '
';
print_r($col);