Providing security for webservers against unwanted and automated registrations has become a big concern. To prevent these kinds of false registrations many websites use CAPTCHAs. Among all kinds of CAPTCHAs OCR-Based or visual CAPTCHAs are very common. Actually visual CAPTCHA is an image containing a sequence of characters. So far most of visual CAPTCHAs, in order to resist against OCR programs...

Image smoothing is a fundamental low-level vision task that aims to preserve salient structures of an image while removing insignificant details. Deep learning has been explored in deal with the complex entanglement semantic and trivial However, current methods neglect two important facts smoothing: 1) naive pixel-level regression supervised by limited number high-quality ground-truth could lea...

The paper analyzes the interaction between humans and computers in terms of response time in solving the image-based CAPT-CHA. In particular, the analysis focuses on the attitude of the different Internet users in easily solving four different types of image-based CAPTCHAs which include facial expressions like: animated character, old woman, surprised face, worried face. To pursue this goal, an...

Deep learning has brought unprecedented progress to image inpainting. However, the existing methods often generate images with blurry textures and distorted structures because they may either fail maintain semantic consistency or restore fine-grained textures. In this paper, we propose a two-stage adversarial model further improve accuracy of structure details Our splits inpainting task into tw...

For the last ten years, CAPTCHAs have been widely used by websites to prevent their data being automatically updated by machines. By supposedly allowing only humans to do so, CAPTCHAs take advantage of the reverse Turing test (TT), knowing that humans are more intelligent than machines. Generally, CAPTCHAs have defeated machines, but things are changing rapidly as technology improves. Hence, ad...

purpose: the purpose of the present study is to investigate the image search and retrieval problems in selected search engines in relation to the persian writing style challenges. methodology: this study is an applied one. in orderto answer the questions an evaluative method and direct observation were used. the aim of the research is to explore the morphological and semantic problems of persia...

Optical character recognition (OCR) is one of the fundamental problems in artificial intelligence and image processing, but recent progress in OCR represents a security challenge for Web sites that throttle requests with image based CAPTCHAs (Completely Automated Public Turing Tests to Tell Computers and Humans Apart). A CAPTCHA is challengeresponse test placed within web forms to determine whe...