org\Verify::_writeNoise PHP Метод

    private function _writeNoise()
    {
        $codeSet = '2345678abcdefhijkmnpqrstuvwxyz';
        for ($i = 0; $i < 10; $i++) {
            //杂点颜色
            $noiseColor = imagecolorallocate($this->_image, mt_rand(150, 225), mt_rand(150, 225), mt_rand(150, 225));
            for ($j = 0; $j < 5; $j++) {
                // 绘杂点
                imagestring($this->_image, 5, mt_rand(-10, $this->imageW), mt_rand(-10, $this->imageH), $codeSet[mt_rand(0, 29)], $noiseColor);
            }
        }
    }