difficult readable captcha code

[realcoder]

anybody tell me or give a code of difuclt captcha 😕
which become diffuclt to read

[dagon]

PHP Captcha Security Images

want to make it more difficult to read change

   $background_color = imagecolorallocate($image, 255, 255, 255);
      $text_color = imagecolorallocate($image, 20, 40, 100);

to

   $background_color = imagecolorallocate($image, 0, 0, 0);
      $text_color = imagecolorallocate($image, 0, 0, 0);

[realcoder]

is this good captcha mean not breakable ? reliable

[dagon]

they all can be 'broken', human labour is cheap, depends what you're protecting whether the protection is sufficient.

recaptcha is good and does all the work for you.

[realcoder]

thanks m also trying this google captcha but m noticing that if we enter only first 4 5 word correct and then if we enter any wrong word google accept that captcha with that wrong word why it happened