问题
I need to show only the numeric reCaptha instead of character strings. Is it possible? If yes, please give the procedure.
Like Google's Street view
回答1:
It is not possible at the moment. Your only options for customisation are basically just skins/themes.
If such an option were available, it would also not be in the options passed through on the client side as a bot could just request it as an easier alternative. Even the plugins only generate javascript to display the widget.
So the option would have to be server side, associated with your key and there are no options to do this when you create your key.
As mentioned in the Google blog, the numbers show up when it has decided you are likely human, so it gives you numbers to make it easier.
回答2:
Google have already made significant advancements to reCAPTCHA technology. However, numeric only CAPTCHA is not possible yet. The updated system uses advanced risk analysis techniques, actively considering the user’s entire engagement with the CAPTCHA—before, during and after they interact with it. That means that today the distorted letters serve less as a test of humanity and more as a medium of engagement to elicit a broad range of cues that characterize humans and bots.
Google's last update involves different classes of CAPTCHAs for different kinds of users. This multi-faceted approach allows us to determine whether a potential user is actually a human or not, and serve our legitimate users CAPTCHAs that most of them will find easy to solve. Bots, on the other hand, will see CAPTCHAs that are considerably more difficult and designed to stop them from getting through.
Humans find numeric CAPTCHAs significantly easier to solve than those containing arbitrary text and achieve nearly perfect pass rates on them. So with our new system, you’ll encounter CAPTCHAs that are a breeze to solve. Bots, however, won’t even see them.
Developer's Guide for Old Google reCAPTCHA.
Google have introduced the new reCAPTCHA! with a caption "No CAPTCHA reCAPTCHA"
The new reCAPTCHA is available on A significant number of your users can now attest they are human without having to solve a CAPTCHA. Instead with just a single click they’ll confirm they are not a robot. We’re calling it the No CAPTCHA reCAPTCHA experience.
On websites using this new API, a significant number of users will be able to securely and easily verify they’re human without actually having to solve a CAPTCHA. Instead, with just a single click, they’ll confirm they are not a robot.
The new reCAPTCHA advantages:
- Advanced Security by state of the art spam & abuse protection for websites
- Ease of Use with low friction, effortless interaction for users.
- Creation of Value by applying the human bandwidth to benefit people everwhere
Developer's Guide for New Google reCAPTCHA.
来源：https://stackoverflow.com/questions/20217123/how-do-get-only-numeric-recaptcha