Code:
<?php
session_start();
$width = 80;
$height = 20;
$im = imagecreate($width, $height);
$bg = imagecolorallocate($im, 0, 0, 0);
// generate random string
$len = 5;
$chars = '0123456789';
$string = '';
for ($i = 0; $i < $len; $i++) {
$pos = rand(0, strlen($chars)-1);
$string .= $chars{$pos};
}
$_SESSION['captcha_code'] = md5($string);
// grid
$grid_color = imagecolorallocate($im, 75, 0, 0);
$number_to_loop = ceil($width / 20);
for($i = 0; $i < $number_to_loop; $i++) {
$x = ($i + 1) * 20;
imageline($im, $x, 0, $x, $height, $grid_color);
}
$number_to_loop = ceil($height / 10);
for($i = 0; $i < $number_to_loop; $i++) {
$y = ($i + 1) * 10;
imageline($im, 0, $y, $width, $y, $grid_color);
}
// write the text
$text_color = imagecolorallocate($im, 255, 0, 0);
$rand_x = rand(0, $width - 50);
$rand_y = rand(0, $height - 15);
imagestring($im, 10, $rand_x, $rand_y, $string, $text_color);
header ("Content-type: image/png");
imagepng($im);
?> |
