Creation and solution of image processing based CAPTCHA test

With the development of web-based technologies, it has been observed that the number of software called “bot” in the Internet tends to increase. As a result of this increase, the internet sites have become unable to use the resources in their hands efficiently. In this study, CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) test, which is proposed to prevent bot software, was created and solved using image processing techniques. In this context, sample texts were created and the letters were analyzed. Performance analyses were carried out with experimental results. As a result of the tests performed, it has been observed that the tests performed with the template matching method can be resolved at a satisfactory level of accuracy. In addition, it has been found that the resolution rates decrease significantly with the addition of geometric distortions to the test texts.