VidCaptcha – A Video Based Captcha to defeat Spam and Bots

Abstract

In the present prevailing networking scenario, the advent of modern decryption tools and other security countermeasures have put the hackers and spammers in the drivers' seat. The concept of a captcha (Completely Automated Turing test to tell Computers and Humans Apart) is used widely in order to verify whether the transaction has been performed by a human or some bot machine. But, with the sophisticated imagery and deciphering tools available today, the normal text captcha is easily susceptible to fooling by the hackers or the bots. The various complex word formations have been undone by some clever programmers. This lead to the development of animated captchas, which were up to now secure and unbreakable. But this too no longer holds true as researchers have unearthed methods to detect animated characters as well. So, it is high time we moved on to a more advanced comprehensive method of implementing the reverse Turing test i.e., by means of a Video captcha [3]. The video captcha can prove to be quite a challenge to the spammers and can be implemented in a fool proof manner. It involves displaying a visual (video) and after watching which the user authenticated himself to be a human by answering to a simple question connected to the video shown. The video may be animated or even real videos. This kind of a captcha requires advanced digital image processing which is a tedious and strenuous process and doesn't work suitably well for deciphering videos. An example of a video captcha is follows – A video of 3 red cars crossing a street along with 2 green buses may be shown by the security service, and a question may be asked as number of red cars in the video shown. The response of the human being shows that it is not a bot and authenticates the user. Thus this paper deals with the creation of a video captcha that can comprehensively beat bots and spammers and enhance the security of the web resources