$width = 145;
$height = 45;
$authcode = Vcaptcha_read_code (' words.txt ');
$BG = ' bg/captcha_bg3.jpg ';
$img _type = ' png ';
/* Verification Code length */
$letters = strlen ($authcode);
$img _BG = (function_exists (' Imagecreatefromjpeg ') && ((Imagetypes () & Img_jpg) > 0))?
Imagecreatefromjpeg ($BG): Imagecreatefromgif ($BG);
$BG _width = imagesx ($img _bg);
$BG _height = Imagesy ($img _bg);
$img _org = ((function_exists (' Imagecreatetruecolor ')) && php_version >= ' 4.3 ')?
Imagecreatetruecolor ($width, $height): Imagecreate ($width, $height);
/* Copy the original image and resize the background image */
if (function_exists (' imagecopyresampled ') && php_version >= ' 4.3 ')//GD 2.x
{
Imagecopyresampled ($img _org, $img _bg, 0, 0, 0, 0, $width, $height, $bg _width, $BG _height);
}
else//GD 1.x
{
Imagecopyresized ($img _org, $img _bg, 0, 0, 0, 0, $width, $height, $bg _width, $BG _height);
}
Imagedestroy ($img _BG);
$CLR = Imagecolorallocate ($img _org, 255, 255, 255);
/* Draw Border */
Imagerectangle ($img _org, 0, 0, $width-1, $height-1, $CLR);
/* Get the height and width of the verification code */
$x = ($width-(Imagefontwidth (5) * $letters))/2;
$y = ($height-imagefontheight (5))/2;
Imagestring ($img _org, 5, $x, $y, $authcode, $CLR);
Header (' Expires:thu, 1970 00:00:00 GMT ');
http/1.1
Header (' Cache-control:private, No-store, No-cache, Must-revalidate ');
Header (' Cache-control:post-check=0, pre-check=0, max-age=0 ', false);
http/1.0
Header (' Pragma:no-cache ');
if ($img _type = = ' jpeg ' && function_exists (' imagecreatefromjpeg '))
{
Header (' Content-type:image/jpeg ');
Imageinterlace ($img _org, 1);
Imagejpeg ($img _org, FALSE, 95);
}
Else
{
Header (' content-type:image/png ');
Imagepng ($img _org);
}
Imagedestroy ($img _org);
function Vcaptcha_read_code ($wordlist _file)
{
$fp = @fopen ($wordlist _file, ' RB ');
if (! $fp) return false;
$fsize = filesize ($wordlist _file);
if ($fsize <) return false; Too small of a list to be effective
if ($fsize < 128) {
$max = $fsize; Still pretty small but changes the range of seeking
} else {
$max = 128;
}
Fseek ($FP, rand (0, $fsize-$max), seek_set);
$data = Fread ($fp, 128); Read a random bytes from file
Fclose ($FP);
$data = Preg_replace ("/r?n/", "n", $data);
$start = Strpos ($data, "n", rand (0, 100)) + 1; Random Start position
$end = Strpos ($data, "n", $start); Find end of Word
Return Strtolower (substr ($data, $start, $end-$start)); Return substring in bytes
} |
