Using mono chrome image in secure data transfer based on book cipher

In the current digitalized world human race confront huge and fast technical progress in communication networks, That contribute to exposure of data and information that is transmitted through these networks to different levels of exposure and attack Also, the authentication of the digital products and services become very important to both makers and customers and can be separated from those that are invalid , The science of transfer secret data in several multimedia carriers like audio , text, video or image so that can achieve the authentication requirements that were mentioned is called steganography. This paper introduces a new steganography technique that will increase the difficulty of exhaustive key search, it based on book cipher combined with ASCII (American Standard for Information interchange) mapping technique using image as reference key.