<?php

# captcha.php
#######################################
# HTTP Viewer Captcha Version © 2012 Scott Connell
# Created: 2012/10/04 (year/month/day)
# License: Free for personal and commercial use.
# Terms: Redistribution/republishing strictly forbidden.
# Source: http://scottconnell.orgfree.com
#######################################

include_once("config.php");

$textkey = $_COOKIE['UID'];

$width = 200;
$height = 60;

$image = ImageCreate($width, $height) or die("Cannot Create image");
$white = imagecolorallocate($image, 255, 255, 255);
$black = imagecolorallocate($image, 0, 0, 0);

imagettftext($image, 40, 0, 25, 50, $black, $font_path, $textkey);

$image2 = ImageCreate($width, $height) or die("Cannot Create image");

$grayscale0 = imagecolorallocate($image2, 153, 153, 153);
$grayscale1 = imagecolorallocate($image2, 178, 178, 178);
$grayscale2 = imagecolorallocate($image2, 204, 204, 204);
$grayscale3 = imagecolorallocate($image2, 229, 229, 229);
$grayscale4 = imagecolorallocate($image2, 255, 255, 255);

for($x=0;$x<$width;$x++)
{
	for($y=0;$y<$height;$y++)
	{
	$random = mt_rand(0, 4);
		
		if(!$random)
		{
		imagesetpixel($image2, $x, $y, $grayscale0);
		}
		if($random == 1)
		{
		imagesetpixel($image2, $x, $y, $grayscale1);
		}
		if($random == 2)
		{
		imagesetpixel($image2, $x, $y, $grayscale2);
		}
		if($random == 3)
		{
		imagesetpixel($image2, $x, $y, $grayscale3);
		}
		if($random == 4)
		{
		imagesetpixel($image2, $x, $y, $grayscale4);
		}
	}
}

imagecopymerge($image, $image2, 0, 0, 0, 0, $width, $height, 60);

		$x_period = 10;
		$y_period = 10;
		$y_amplitude = 5;
		$x_amplitude = 5;
		
		$xp = $x_period*rand(1,3);
		$k = rand(0,100);
		for ($a = 0; $a<$width; $a++)
		{
		imagecopy($image, $image, $a-1, sin($k+$a/$xp)*$x_amplitude, $a, 0, 1, $height);
		}
			
		$yp = $y_period*rand(1,2);
		$k = rand(0,100);
		for ($a = 0; $a<$height; $a++)
		{
		imagecopy($image, $image, sin($k+$a/$yp)*$y_amplitude, $a-1, 0, $a, $width, 1);
		}

header("Content-type: image/png");
header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1
header("Expires: Wed, 22 Jul 1964 22:00:00 GMT"); // In the past
header("Pragma: no-cache");

imagepng($image);
imagedestroy($image);
imagedestroy($image2);

?>