captcha-code-authentication / captcha_code_file.php

captcha_code_file.php in Captcha Code 2.7, at captcha_code_file.php

126 lines 3.5 KB

Raw Download Zip

1	<?php
2	session_start();
3
4	//Settings: You can customize the captcha here
5	$image_width = 120;
6	$image_height = 40;
7
8	$characters_on_image = 6;
9	if(isset($_SESSION['total_no_of_characters']))
10	$characters_on_image = $_SESSION['total_no_of_characters'];
11
12	$font = dirname(__FILE__) . '/monofont.ttf';
13
14	//The characters that can be used in the CAPTCHA code.
15	//avoid confusing characters (l 1 and i for example)
16	if(isset($_SESSION['captcha_type']) && $_SESSION['captcha_type'] == 'alphanumeric')
17	{
18	switch($_SESSION['captcha_letters'])
19	{
20	case 'capital':
21	$possible_letters = '23456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
22	break;
23	case 'small':
24	$possible_letters = '23456789bcdfghjkmnpqrstvwxyz';
25	break;
26	case 'capitalsmall':
27	$possible_letters = '23456789bcdfghjkmnpqrstvwxyzABCEFGHJKMNPRSTVWXYZ';
28	break;
29	default:
30	$possible_letters = '23456789bcdfghjkmnpqrstvwxyz';
31	break;
32	}
33	}
34	elseif(isset($_SESSION['captcha_type']) && $_SESSION['captcha_type'] == 'alphabets')
35	{
36	switch($_SESSION['captcha_letters'])
37	{
38	case 'capital':
39	$possible_letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
40	break;
41	case 'small':
42	$possible_letters = 'bcdfghjkmnpqrstvwxyz';
43	break;
44	case 'capitalsmall':
45	$possible_letters = 'bcdfghjkmnpqrstvwxyzABCEFGHJKMNPRSTVWXYZ';
46	break;
47	default:
48	$possible_letters = 'abcdefghijklmnopqrstuvwxyz';
49	break;
50	}
51	}
52	elseif(isset($_SESSION['captcha_type']) && $_SESSION['captcha_type'] == 'numbers')
53	{
54	$possible_letters = '0123456789';
55	}
56	else
57	{
58	$possible_letters = '0123456789';
59	}
60	$random_dots = 0;
61	$random_lines = 20;
62	$captcha_text_color="0x142864";
63	$captcha_noice_color = "0x142864";
64
65	$code = '';
66
67
68	$i = 0;
69	while ($i < $characters_on_image)
70	{
71	$code .= substr($possible_letters, mt_rand(0, strlen($possible_letters)-1), 1);
72	$i++;
73	}
74
75
76	$font_size = $image_height * 0.75;
77	$image = @imagecreate($image_width, $image_height);
78
79
80	/* setting the background, text and noise colours here */
81	$background_color = imagecolorallocate($image, 255, 255, 255);
82
83	$arr_text_color = hexrgb($captcha_text_color);
84	$text_color = imagecolorallocate($image, $arr_text_color['red'],
85	$arr_text_color['green'], $arr_text_color['blue']);
86
87	$arr_noice_color = hexrgb($captcha_noice_color);
88	$image_noise_color = imagecolorallocate($image, $arr_noice_color['red'],
89	$arr_noice_color['green'], $arr_noice_color['blue']);
90
91
92	/* generating the dots randomly in background */
93	for( $i=0; $i<$random_dots; $i++ )
94	{
95	imagefilledellipse($image, mt_rand(0,$image_width), mt_rand(0,$image_height), 2, 3, $image_noise_color);
96	}
97
98
99	/* generating lines randomly in background of image */
100	for( $i=0; $i<$random_lines; $i++ ) {
101	imageline($image, mt_rand(0,$image_width), mt_rand(0,$image_height), mt_rand(0,$image_width), mt_rand(0,$image_height), $image_noise_color);
102	}
103
104
105	/* create a text box and add 6 letters code in it */
106	$textbox = imagettfbbox($font_size, 0, $font, $code);
107	$x = ($image_width - $textbox[4])/2;
108	$y = ($image_height - $textbox[5])/2;
109	imagettftext($image, $font_size, 0, $x, $y, $text_color, $font , $code);
110
111
112	/* Show captcha image in the page html page */
113	header('Content-Type: image/jpeg');// defining the image type to be shown in browser widow
114	imagejpeg($image);//showing the image
115	imagedestroy($image);//destroying the image instance
116	$_SESSION['captcha_code'] = $code;
117
118	function hexrgb ($hexstr)
119	{
120	$int = hexdec($hexstr);
121
122	return array("red" => 0xFF & ($int >> 0x10),
123	"green" => 0xFF & ($int >> 0x8),
124	"blue" => 0xFF & $int);
125	}
126	?>