<?

function image_random_lines(&$i)
{
	# line count
	$lc = 25;

	$W = imagesx($i);
	$H = imagesy($i);

	for($r = 0; $r < $lc; $r++)
	{
		$c = imagecolorallocate($i, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));
		$x1 = mt_rand(-$W, $W * 2);
		$y1 = mt_rand(-$H, $H * 2);
		$x2 = mt_rand(-$W, $W * 2);
		$y2 = mt_rand(-$H, $H * 2);
		imageline($i, $x1, $y1, $x2, $y2, $c);
	}
} // image_random_line

function image_text_randomize(&$i, $text)
{
	global $sys_root;

	$fonts = array(
		'arial.ttf',
		'cour.ttf',
		'times.ttf',
		'verdana.ttf',
	);
	$W = imagesx($i);
	$H = imagesy($i);

	$l = strlen($text);
	$x = 8;
	$y = 30;
	for($r = 0; $r < $l; $r++)
	{
		$char = $text[$r];
		$c = imagecolorallocate($i, mt_rand(64, 128), mt_rand(64, 128), mt_rand(64, 128));
		$font = "$sys_root/../fonts/".$fonts[array_rand($fonts)];
		$angle = mt_rand(-45, 45);
		$fs = mt_rand(16, 20);
		list($llX, $llY, $lrX, $lrY, $urX, $urY, $ulX, $ulY) = imagettfbbox($fs, $angle, $font, $char);
		$x1 = $llX > $ulX ? $llX : $ulX;
		$y1 = $llY > $ulY ? $llY : $ulY;
		$x2 = $lrX > $urX ? $lrX : $urX;
		$y2 = $lrY > $urY ? $lrY : $urY;
		$width = $x2 - $x1;
		$height = $y2 - $y1;

		imagettftext($i, $fs, $angle, $x, $y, $c, $font, $char);
		$x += $width + 8;
	}
} // image_text_randomize

header("Content-type: image/gif");
$i_w = 120;
$i_h = 40;

$i = imagecreatetruecolor($i_w, $i_h);
$bg = imagecolorallocate($i, 255, 255, 255);
imagefill($i, 0, 0, $bg);

image_random_lines($i);
$_SESSION['imgcode']['text'] = strtoupper(substr(md5(uniqid(rand())), 0, 4));
image_text_randomize($i, $_SESSION['imgcode']['text']);

imagegif($i);

$NO_CONTENT_TYPE = true;

?>