Recognizing the Adhesion Hollow Characters Based on the Closed Cutting Algorithm
With the development of network security, CAPTCHA identification is becoming a hot research topic. In this paper, we study the adhesion hollow character in the CAPTCHA, and put forward a method to identify the hollow characters which are adhered to each other in the CAPTCHA. The method is based on the principle of virus invading cells, and uses the particle swarm algorithm to find the closed space and fill it. We determine the location of the character by the histogram of number of layers, and then recognize the characters that are cut out. Experimental results show that the proposed method can be effectively used to identify the hollow characters in the CAPTCHA, and the recognition rate is 30.1%.
KeywordsCAPTCHA Closure detection Shape context Bionics Recognition
This work was funded by the National Natural Science Foundation of China (61772282, 61373134, and 61402234). It was also supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX17_0901) and Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology (CICAEET). We declare that we do not have any conflicts of interest to this work.
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