OPTP: A new steganography scheme with high capacity and security

Steganography is the art of hiding secret information (text, audio, video, image or file) in a cover medium. Our goal in this paper is to propose a new image steganography scheme that simultaneously increases capacity and security. Increasing these two characteristics at the same time while maintaining the quality of the extracted secret image is a big challenge for scheme designers, and requires a trade-off. In the present paper, a new steganography scheme called OPTP is introduced in the spatial domain, where for the first time, One secret Picture is sent using only Two cover Pictures; therefore the name OPTP. In this method, two stego images are generated for each secret image using a simple equation, which brings higher capacity, security and quality compared to other existing schemes. To increase the capacity, we introduced a new lossy compression algorithm that performs better compared to conventional compression methods. Regarding the security, we used a key without initial handshake, and bloom filter is employed for the verification. We will compare features and results of the proposed scheme with some existing and recent schemes in the literature.