Captcha.....

What's the percentage of success of the contemporary captcha visual encoders?

I thought I would try to implement one myself in JAVA.

Any advise appreciated!

implementing one should be rather easy, however modern OCR should be much much better than such a simplistic attempt, and since one of the two words reCAPTCHA supplies is a word that two different OCR software gave different readings to (but even if you give the 'wrong' reading it can't know), an acceptable success rate should be possible using the state-of-the art propriety computer vision software.