/*
     * 补全外围空白像素点
     */
    static private function _addOutPx($font, $px = 0) {
        $maxRow = 0;
        $x0 = 0;//x轴的相对0点,因为使用公式产生的数组有负数下标,需要得到绝对0点
        
        foreach($font as $row) {//得到最长行
            $x0 = min($x0, key($row));
            end($row);//移到最后一个
            $maxRow = max($maxRow, key($row));
        }       
        $maxRow = $maxRow - $x0 + 1;
        
        foreach ($font as $key => $row) {
            $tmp = array();
            end($row);
            $xe = key($row);
            
            for ($x = $x0; $x <= $xe; $x++) {//把空值补上
                $tmp[] = empty($row[$x]) ? 0 : 1;
            }
            
            if ($px < 1) {//不加边
                if ($maxRow == count($tmp)) {//不变
                    $font[$key] = $tmp;
                } else{//需要补全行
                    $font[$key] = array_pad($tmp, $maxRow, 0);
                }
            } else {//需要加边和补全行
                $font[$key] = array_merge(array_fill(0, $px, 0), $tmp, array_fill(0, $maxRow + $px - count($tmp), 0));//增加左右二边
            }
        }
        if ($px < 1) {//不加边
            return $font;
        } else {
            $tmp = array_fill(0, $px, array_fill(0, $maxRow + 2 * $px, 0));
            return array_merge($tmp, $font, $tmp);//增加上下二边
        }
    }
    /*     * 使用坐标点旋转(矩阵旋转)算法(旋转坐标公式)     * X’=X*Cos(φ)-Y*Sin(φ)
     * Y’=X*Sin(φ)+Y*Cos(φ)
     */
    static private function _turnLR($font, $px) {
        if (0 == $px) {
            return $font;
        }

        $tmp = array();
        $size = 10;
        $yt = count($font) - 1;
        
        foreach ($font as $y => $row) {
            //$y = $yt - $y;//因为数组存放方式跟y坐标反了
            
            foreach ($row as $x => $cell) {
                $nx = floor($size * ($x * cos($px) - $y * sin($px)));
                $ny = floor($size * ($x * sin($px) + $y * cos($px)));//*倍数,不让失真过大
                
                if (! isset($tmp[$ny])) {
                    $tmp[$ny] = array();
                }
                            
                $tmp[$ny][$nx] = $cell;
            }
        }       
        $tmp = captcha::_addOutPx($tmp);//补足空位
        exit(captcha::_show2d($tmp));
        return $tmp;
    }
    /*     * 先生成文字图片,再根据像素点黑白二极化,输出字符码     */
    static private function _showMakeFontBar() {
        $fontW = 5;//使用默认字体,最大号
        $fh = imagefontheight($fontW);
        $fw = imagefontwidth($fontW);
        echo '把下面的代码放到char2BW函数中:<pre>';
        $str = STR;

        for ($i = 0; $i < strlen($str); $i++) {
            $im = imagecreatetruecolor($fw, $fh);
            $white = imagecolorallocate($im, 255, 255, 255);
            $char = $str{$i};
            echo "\t\tcase '{$char}':\n\t\t\treturn ";
            imagechar($im, $fontW, 0, 0, $char, $white);
            //imagepng($im, $char.'.png');//输出测试图片
            $outTmp = array();

            for ($c = 0; $c < $fh; $c++) {
                $ra = array();
                for ($r = 0; $r < $fw; $r++) {
                    $ra[] = (int) 0 != imagecolorat($im, $r, $c) & 0xFF;//得到黑白码
                }
                $outTmp[] = 'array(' .implode(',', $ra). ')';
            }
            $aCode = "array(" .implode(',', $outTmp). ")";
            $aCode = preg_replace("/array\((array\(0(,0)*\),)+/", 'array(', $aCode);//平切顶空白
            $aCode = preg_replace("/(,array\(0(,0)*\))+\)/", ')', $aCode);//平切底空白
            $aCode = preg_replace("/(,0)+\)/", ')', $aCode);//"全"切右空白
            while (preg_match("/^array\(array\(0(,[01])*\)(,array\(0(,[01])*\))*\)$/", $aCode)) {//平切左空白
                $aCode = str_replace("array(0,", 'array(', $aCode);
            }
            echo $aCode. ";\n";
            eval("show2d({$aCode});");//输出测试二极2d码
        }
        echo '</pre>';
    }
    /*     * 字符转二维码     */
    static private function _getCharCode($str) {
        $pxs = array();
        $maxCell = 0;

        for ($si = 0; $si < strlen($str); $si++) {
            $code = captcha::_char2BW($str{$si});

            if (is_null($code)) {//没有此字
                continue;
            }

            //对字体变形
            $lr = 0;//rand(-1, 1);

            if ($lr != 0) {
                $code = captcha::_turnLR($code, $lr);
            }
            
            $code = captcha::_addOutPx($code, 1);//为字加边
    /*
            $size = 0;//rand(0, 2);
            $code = doHeights($code, $size);
            $code = doWidths($code, $size);
            */
            $cCount = 0;
            $moveY = rand(0, round(count($pxs) / 2));//字y点与0点偏移量

            foreach ($code as $r => $row) {

                if (! isset($pxs[$r + $moveY])) {
                    $pxs[$r + $moveY] = array();
                }
                $cCount = max(count($row), $cCount);//记住最长行
                $pxsR = & $pxs[$r + $moveY];//引用,方便
                if ($maxCell > count($pxsR)) {//本行没有跟前字最长行平整,必须补0
                    $pxsR = array_pad($pxsR, $maxCell, '0');//使用0补足
                }
                foreach($row as $cell) {
                    $pxsR[] = $cell;//把每个字的相同横行拼一起
                }
            }
            $maxCell += $cCount;//全字符最长行
        }
        return captcha::_addOutPx($pxs, 1);//补全外围
    }
    /* 输出二维码式的字形     */
    static private function _show2d($chars) {
        echo '<br/>/*<br/>';

        foreach($chars as $val) {
            foreach($val as $tmp) {
                echo empty($tmp) ? '.' : '<span style="color:red;">*</span>';
            }
            echo '<br/>';
        }

        echo '*/<br/>';
    }
    /* 回字符对应二极码*/
    static private function _char2BW($char) {
        if (! is_string($char)) {
            return null;
        }

        switch ($char) {

            case 'a':
                return array(array(0,0,1,1,1,1,1),array(0,1,1,0,0,0,1,1),array(0,0,0,0,0,0,1,1),array(0,1,1,1,1,1,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,1,1,1),array(0,1,1,1,1,0,1,1));
            case 'A':
                return array(array(0,0,0,1,1),array(0,0,1,1,1,1),array(0,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,1,1,1,1,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1));
            case 'b':
                return array(array(1,1),array(1,1),array(1,1),array(1,1,0,1,1,1),array(1,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,1,0,0,1,1),array(1,1,0,1,1,1));
            case 'B':
                return array(array(1,1,1,1,1,1),array(1,1,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,1,1),array(1,1,1,1,1,1),array(1,1,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,1,1),array(1,1,1,1,1,1));
            case 'd':
                return array(array(0,0,0,0,0,0,1,1),array(0,0,0,0,0,0,1,1),array(0,0,0,0,0,0,1,1),array(0,0,1,1,1,0,1,1),array(0,1,1,0,0,1,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1,1),array(0,0,1,1,1,0,1,1));
            case 'D':
                return array(array(1,1,1,1,1,1),array(1,1,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,1,1),array(1,1,1,1,1,1));
            case 'e':
                return array(array(0,0,1,1,1,1),array(0,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,1,1,1,1,1,1),array(1,1),array(0,1,1,0,0,0,1,1),array(0,0,1,1,1,1,1));
            case 'E':
                return array(array(1,1,1,1,1,1,1),array(1,1),array(1,1),array(1,1),array(1,1,1,1,1,1),array(1,1),array(1,1),array(1,1),array(1,1),array(1,1,1,1,1,1,1));
            case 'f':
                return array(array(0,0,0,1,1,1,1),array(0,0,1,1,0,0,1,1),array(0,0,1,1,0,0,1,1),array(0,0,1,1),array(0,0,1,1),array(1,1,1,1,1,1),array(0,0,1,1),array(0,0,1,1),array(0,0,1,1),array(0,0,1,1));
            case 'F':
                return array(array(1,1,1,1,1,1,1,1),array(1,1),array(1,1),array(1,1),array(1,1,1,1,1,1),array(1,1),array(1,1),array(1,1),array(1,1),array(1,1));
            case 'g':
                return array(array(0,1,1,1,1,1,0,1),array(1,1,0,0,0,1,1,1),array(1,1,0,0,0,1,1),array(1,1,0,0,0,1,1),array(0,1,1,1,1,1),array(1,1),array(0,1,1,1,1,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,1,1,1,1));
            case 'G':
                return array(array(0,0,1,1,1,1,1),array(0,1,1,0,0,0,1,1),array(1,1),array(1,1),array(1,1),array(1,1,0,0,0,1,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,0,1,1),array(0,0,1,1,1,1,1));
            case 'h':
                return array(array(1,1),array(1,1),array(1,1),array(1,1,0,1,1,1),array(1,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1));
            case 'H':
                return array(array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,1,1,1,1,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1));
            case 'i':
                return array(array(0,0,1,1),array(0,0,1,1),array(0),array(0,1,1,1),array(0,0,1,1),array(0,0,1,1),array(0,0,1,1),array(0,0,1,1),array(0,0,1,1),array(1,1,1,1,1,1));
            case 'J':
                return array(array(0,0,1,1,1,1),array(0,0,0,0,1,1),array(0,0,0,0,1,1),array(0,0,0,0,1,1),array(0,0,0,0,1,1),array(0,0,0,0,1,1),array(0,0,0,0,1,1),array(1,0,0,0,1,1),array(1,1,0,1,1),array(0,1,1,1));
            case 'L':
                return array(array(1,1),array(1,1),array(1,1),array(1,1),array(1,1),array(1,1),array(1,1),array(1,1),array(1,1),array(1,1,1,1,1,1,1));
            case 'm':
                return array(array(1,0,1,1,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,1,1,0,1,1));
            case 'M':
                return array(array(1,1,0,0,0,0,1,1),array(1,1,1,0,0,1,1,1),array(1,1,1,1,1,1,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1));
            case 'n':
                return array(array(1,1,0,1,1,1),array(1,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1));
            case 'N':
                return array(array(1,1,0,0,0,0,1,1),array(1,1,1,0,0,0,1,1),array(1,1,1,1,0,0,1,1),array(1,1,1,1,0,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,0,1,1,1,1),array(1,1,0,0,0,1,1,1),array(1,1,0,0,0,1,1,1),array(1,1,0,0,0,0,1,1));
            case 'q':
                return array(array(0,0,1,1,1,0,1,1),array(0,1,1,0,0,1,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1,1),array(0,0,1,1,1,0,1,1),array(0,0,0,0,0,0,1,1),array(0,0,0,0,0,0,1,1));
            case 'Q':
                return array(array(0,0,1,1,1,1),array(0,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,1,1,0,1,1),array(1,1,0,0,1,1,1,1),array(0,1,1,0,0,1,1),array(0,0,1,1,1,1,0,1));
            case 'r':
                return array(array(1,1,0,1,1,1,1),array(0,1,1,1,0,0,1,1),array(0,1,1),array(0,1,1),array(0,1,1),array(0,1,1),array(0,1,1));
            case 'R':
                return array(array(1,1,1,1,1,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,1,1,1,1,1),array(1,1,1,1,1),array(1,1,0,0,1,1),array(1,1,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1));
            case 't':
                return array(array(0,0,1,1),array(0,0,1,1),array(1,1,1,1,1,1),array(0,0,1,1),array(0,0,1,1),array(0,0,1,1),array(0,0,1,1),array(0,0,1,1,0,0,1,1),array(0,0,0,1,1,1,1));
            case 'T':
                return array(array(1,1,1,1,1,1,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1));
            case 'y':
                return array(array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1,1),array(0,0,1,1,1,0,1,1),array(1,0,0,0,0,0,1,1),array(0,1,1,1,1,1,1));
            case 'Y':
                return array(array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1),array(0,0,1,1,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1),array(0,0,0,1,1));
            case '2':
                return array(array(0,0,1,1,1,1),array(0,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,0,0,0,0,0,1,1),array(0,0,0,0,0,1,1),array(0,0,0,0,1,1),array(0,0,0,1,1),array(0,0,1,1),array(0,1,1),array(1,1,1,1,1,1,1,1));
            case '3':
                return array(array(0,1,1,1,1,1),array(1,1,0,0,0,1,1),array(0,0,0,0,0,0,1,1),array(0,0,0,0,0,1,1),array(0,0,0,1,1,1),array(0,0,0,0,0,1,1),array(0,0,0,0,0,0,1,1),array(0,0,0,0,0,0,1,1),array(1,1,0,0,0,1,1),array(0,1,1,1,1,1));
            case '4':
                return array(array(0,0,0,0,0,1,1),array(0,0,0,0,1,1,1),array(0,0,0,1,1,1,1),array(0,0,1,1,0,1,1),array(0,1,1,0,0,1,1),array(1,1,0,0,0,1,1),array(1,1,1,1,1,1,1,1),array(0,0,0,0,0,1,1),array(0,0,0,0,0,1,1),array(0,0,0,0,0,1,1));
            case '5':
                return array(array(1,1,1,1,1,1,1),array(1,1),array(1,1),array(1,1,0,1,1,1),array(1,1,1,0,0,1,1),array(0,0,0,0,0,0,1,1),array(0,0,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1),array(0,0,1,1,1,1));
            case '6':
                return array(array(0,0,1,1,1,1),array(0,1,1,0,0,1,1),array(1,1,0,0,0,0,1),array(1,1),array(1,1,0,1,1,1),array(1,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1),array(0,0,1,1,1,1));
            case '7':
                return array(array(1,1,1,1,1,1,1,1),array(0,0,0,0,0,0,1,1),array(0,0,0,0,0,0,1,1),array(0,0,0,0,0,1,1),array(0,0,0,0,1,1),array(0,0,0,1,1),array(0,0,1,1),array(0,1,1),array(1,1),array(1,1));
            case '8':
                return array(array(0,0,1,1,1,1),array(0,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1),array(0,0,1,1,1,1),array(0,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1),array(0,0,1,1,1,1));
            case '9':
                return array(array(0,0,1,1,1,1),array(0,1,1,0,0,1,1),array(1,1,0,0,0,0,1,1),array(1,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1,1),array(0,0,1,1,1,0,1,1),array(0,0,0,0,0,0,1,1),array(0,1,0,0,0,0,1,1),array(0,1,1,0,0,1,1),array(0,0,1,1,1,1));
            default:
                return null;
        }
    }
}

-----------代码结束--------