Breaking text-based CAPTCHAs with variable word and character orientation
作者：
Highlights：
• Automatic segmentation and recognition of CAPTCHAs in Web sites is proposed.
• Anti-recognition techniques use collapsed characters with variable orientation.
• Aligned word and straightened characters are segmented by three-color bar code.
• Original SVM-based learning classifier provides real-time CAPTCHA recognition.
• Extended approach for beating reCAPTCHA of version 2012 shows better performance.
摘要
•Automatic segmentation and recognition of CAPTCHAs in Web sites is proposed.•Anti-recognition techniques use collapsed characters with variable orientation.•Aligned word and straightened characters are segmented by three-color bar code.•Original SVM-based learning classifier provides real-time CAPTCHA recognition.•Extended approach for beating reCAPTCHA of version 2012 shows better performance.
论文关键词：Breaking CAPTCHA,reCAPTCHA Version 2012,Word and character straightening,Three-color bar character encoding,Heuristic classifier
论文评审过程：Received 2 January 2014, Revised 3 September 2014, Accepted 8 September 2014, Available online 21 September 2014.
论文官网地址：https://doi.org/10.1016/j.patcog.2014.09.006
