Código PHP:
<?php
class captchaZDR {
var $UserString;
var $font_path;
function captchaZDR(){
switch(rand(1,3))
{
case 1 : $this->font_path = 'png_bank/font.ttf'; break;
case 2 : $this->font_path = 'png_bank/freemonobold.ttf'; break;
case 3 : $this->font_path = 'png_bank/freesans.ttf'; break;
default : $this->font_path = 'png_bank/font.ttf'; break;
}
}
function LoadPNG(){
$bgNUM = rand(1,8);
$im = @imagecreatefrompng('png_bank/bg'.$bgNUM.'.png'); /* Attempt to open */
if (!$im) {
$im = imagecreatetruecolor(150, 30); /* Create a blank image */
$bgc = imagecolorallocate($im, 255, 255, 255);
$tc = imagecolorallocate($im, 0, 0, 0);
imagefilledrectangle($im, 0, 0, 150, 30, $bgc);
imagestring($im, 1, 5, 5, "Error loading $imgname", $tc);
}
return $im;
}
function drawElipse($image){
for($i=0;$i<5;$i++){
// choose a color for the ellipse
$red = rand(0,155);
$green = rand(0,155);
$blue = rand(0,155);
$col_ellipse = imagecolorallocate($image, $red, $green, $blue);
// draw the ellipse
$cx = rand(50,250);
$cy = rand(50,250);
$cw = rand(30,250);
$ch = rand(20,250);
imageellipse($image, $cx, $cy, $cw, $ch, $col_ellipse);
}
foreach (range('A', 'Z') as $letter) {
$red = rand(0,155);
$green = rand(0,155);
$blue = rand(0,155);
$col_ellipse = imagecolorallocate($image, $red, $green, $blue);
$font_size = 3; //rand(1,12);
$x = rand(0,200);
$y = rand(0,100);
imagechar($image, $font_size, $x, $y, $letter, $col_ellipse);
}
foreach (range('0', '9') as $letter) {
$red = rand(0,155);
$green = rand(0,155);
$blue = rand(0,155);
$col_ellipse = imagecolorallocate($image, $red, $green, $blue);
$font_size = 1;
$x = rand(0,200);
$y = rand(0,100);
imagechar($image, $font_size, $x, $y, $letter, $col_ellipse);
}
}
function task_string(){
// create a image from png bank
$image = $this->LoadPNG();
$string_a = array("A","B","C","D","E","F","G","H","J","K",
"L","M","N","P","R","S","T","U","V","W","X","Y","Z",
"2","3","4","5","6","7","8","9");
$width = 0;
for($i=0;$i<5;$i++)
{
$colour = imagecolorallocate($image, rand(0,155), rand(0,155), rand(0,155));
$font = $this->font_path;
$angle = rand(-15,15);
// Add the text
$width_pos = rand(10,30);
$width = $width + $width_pos;
$height = rand(30,30);
$temp = $string_a[rand(0,25)];
$this->UserString .= $temp;
imagettftext($image, 26, $angle, $width, $height, $colour, $font, $temp);
$width = $width + 3;
$height = $height + 3;
imagettftext($image, 26, $angle, $width, $height, $colour, $font, $temp);
}
$_SESSION['captcha'] = $this->UserString;
return $image;
}
function task_sum(){
// create a image from png bank
$image = $this->LoadPNG();
$colour = imagecolorallocate($image, rand(0,155), rand(0,155), rand(0,155));
$font = $this->font_path;
$angle = rand(-15,15);
// Add the text
$width = rand(20,30);
$height = rand(35,30);
$number1 = rand(1,99);
$number2 = rand(1,9);
imagettftext($image, 26, $angle, $width, $height, $colour, $font, $number1);
$colour = imagecolorallocate($image, rand(0,155), rand(0,155), rand(0,155));
$width += 45;
imagettftext($image, 26, 0, $width, $height, $colour, $font, '+');
$colour = imagecolorallocate($image, rand(0,155), rand(0,155), rand(0,155));
$width += 25;
$angle = rand(-15,15);
imagettftext($image, 26, $angle, $width, $height, $colour, $font, $number2.'=?');
$this->UserString = $number1+$number2;
$_SESSION['captcha'] = $this->UserString;
return $image;
}
function task_deduction(){
// create a image from png bank
$image = $this->LoadPNG();
$colour = imagecolorallocate($image, rand(0,155), rand(0,155), rand(0,155));
$font = $this->font_path;
$angle = rand(-15,15);
// Add the text
$width = rand(20,30);
$height = rand(35,30);
$number1 = rand(1,99);
$number2 = rand(1,9);
imagettftext($image, 26, $angle, $width, $height, $colour, $font, $number1);
$colour = imagecolorallocate($image, rand(0,155), rand(0,155), rand(0,155));
$width += 45;
imagettftext($image, 26, 0, $width, $height, $colour, $font, '-');
$colour = imagecolorallocate($image, rand(0,155), rand(0,155), rand(0,155));
$width += 25;
$angle = rand(-15,15);
imagettftext($image, 26, $angle, $width, $height, $colour, $font, $number2.'=?');
$this->UserString = $number1-$number2;
$_SESSION['captcha'] = $this->UserString;
return $image;
}
function display(){
switch(rand(1,3))
{
case 1 : $image = $this->task_string(); break;
case 2 : $image = $this->task_string(); break;
case 3 : $image = $this->task_string(); break;
default : $image = $this->task_string(); break;
}
$this->drawElipse($image);
// output the picture
header("Content-type: image/png");
imagepng($image);
}
function check_result(){
if(!isset($_SESSION['captcha']) || $_SESSION['captcha']!=$_REQUEST['capt'] || $_SESSION['captcha']=='BADCODE')
{
$_SESSION['captcha']='BADCODE';
return false;
}
else
{
return true;
}
}
}
?>