Abstract: This paper presents an evaluation of image based authentication using hidden codes and random code generated in graphical password scheme. Now a days authentication is a very critical problem in security system. Unauthorized user or hacker can easily stole the information contains in a system by using proxy password or by capturing the gallery where different passwords get generated in it. This has been solved by the fact the humans have a natural inclination to remember images more easily than text. As images are better to remember. Here we have proposed a graphical password authentication where it will consists of number of images and each image is hidden by a specified character which cannot view to user and this will set it as his password for login page. A new algorithm that using watermarking for the images which will be watermarked and Image based authentication using hidden codes and random code generator technique as the solution to solving image gallery attacks and using the random character set generation for each image for resistance to shoulder surfing attack to provide better system secure.

Keywords: Graphical Password, Watermarked Algorithm, Authentication Security, Shoulder surfing ,image gallery attack