What is the best captcha service available for JSP forms apart from ReCaptcha?

I want to secure my form from spambots by using a captcha service. I have tried ReCaptcha but it generates really hard words. Is there any other captcha service av开发者_运维百科ailable which I can use. I have tried JCaptcha but it is also not very good.

Any help?

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I personally haven't used this service, but you can try OpenCaptcha

There is also SimpleCaptcha

Hope it helps.