Comment by keks24

Google does this for a long time already.

You may want to use "Buster: Captcha Solver for Humans"[1], which uses the audio option to solve the CAPTCHA.

There are even several speech recognition methods, like wit.ai, which is basically from Facebook:

    $ whois wit.ai | grep "Name Server"
    Name Server: b.ns.facebook.com
    Name Server: a.ns.facebook.com
    Name Server: c.ns.facebook.com
    Name Server: d.ns.facebook.com

[1] https://github.com/dessant/buster