›› 2012, Vol. 25 ›› Issue (6): 149-.

• Articles • Previous Articles     Next Articles

A Method for Breaking the Text-based CAPTCHA with Character Features

 GAO Yuan   

  1. (Pizhou City Motor Vehicle Test Station,Pizhou 221300,China)
  • Online:2012-06-15 Published:2012-08-23


This paper introduces a method for breaking the text-based image CAPTCHA based on feature recognition.It also describes the procedures of breaking SPD Bank CAPTCHA in details:preprocessing,extraction,and recognition.In the recognition phase,we propose three feature-based recognition methods for SPD Bank:color-filling,three-lines and full scan.The success rate and the speed of the results are desirable.The experiments show that our attack achieves a success rate of as high as 78%.Both the feature recognition method and the crack method are also applicable to other non-adhesion of the text-based CAPTCHA.

Key words: CAPTCHA;feature recognition;color-filling;three-line;full scan

CLC Number: 

  • TP398.08