You’ve seen CAPTCHAs before, it’s where you type characters in a picture to prove you are human.

The two major issues I’ve experienced with CAPTCHA implementations are:

1. garbled characters
2. image only CAPTCHAs aren’t accessible to sight-impaired

The latter can be resolved by offering a clear text to speech voice option. Unfortunately most created CAPTCHAs don’t (myself included with Form Sentinel) offer voice functionality. On my someday to-do list is adding voice capability to Form Sentinel.

There have been some creative CAPTCHA options like the hotornot CAPTCHA and there’s a new one called reCAPTCHA from Carnegie Mellon University which uses the CAPTCHA to fix OCR (optical character recognition) problems digitizing books:

reCAPTCHA improves the process of digitizing books by sending words that cannot be read by computers to the Web in the form of CAPTCHAs for humans to decipher. More specifically, each word that cannot be read correctly by OCR is placed on an image and used as a CAPTCHA. This is possible because most OCR programs alert you when a word cannot be read correctly.

This is not planned to be a permanent change (if you don’t like this please speak up below) but I’ve reimplemented a CAPTCHA on the comments using reCAPTCHA. It’s already running and working in the comments below. Fellow bloggers with Wordpress can snag the Wordpress plugin here. Note: you’ll need to register at reCAPTCHA to get a public and private key.

We tried CAPTCHA in the comments here once before and I took it away after receiving some complaints from sight-impaired readers. As someone with sight that is getting progressively worse as the years pile on, I can sympathize with these readers. If any sight-impaired readers are disappointed that I’ve readded CAPTCHA, you’ll be delighted to know that this reCAPTCHA offers a voice challenge, woohoo!

I want to help this digitizing books project and would also like sight-impaired readers to be able to leave comments. Readers please let me know what you think of this project and the CAPTCHA being re-enabled in the comments area.

Will this cause you to leave less comments? Do you mind typing in the extra two words or not? Hmm doesn’t require registration to leave comments (to me that’s worse than a CAPTCHA) and it will remember your details in a cookie if you allow them, so all you’d need to type is your comment and two extra words. I’m particularly interested in those who feel this will make them leave less comments than they would without a CAPTCHA in use. The last time I tried CAPTCHA here it didn’t have any negative impact on the number of comments being left and significantly reduced the amount of comment spam. I removed it because of the valid accessibility complaints.

Personally, I don’t mind using CAPTCHA as long as I can read it. I despise CAPTCHAs that I can’t read and won’t keep refreshing the page to get a better looking one, I’ll just pass on leaving a comment.

I like using my Sony PS3 to help find cures and this seems like a good use of the comment feature to help accurately digitize more books and help reduce the growing onslaught of mechanized comment spam. Agree? Disagree? Sight impaired people will benefit from having more digitized books that their text-to-speech readers can read too.

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