Image Steganography-using-Lah-Transform

Due to rapid growth of digital communication attributed to advancement of Internet technologies, at every time instant huge amount of multimedia information is created and transmitted on the Internet. However, ownership identification, copyright violation, and identity theft are proving as the serious concerns because of the malicious attacks or hacking of open information. Attackers can alter or delete the information, and claim the ownership or prevent the receiver to get the data. Hence, researchers try to address such challenges. One such effort is concerned with multimedia data hiding through Steganography. In this article, a polynomial sequence generator called Lah Transform (LhT) is applied for developing a Steganography method. LhT generates an integer polynomial sequence in coefficient form by evaluating the pixel values using addition and multiplication. Initially, the cover image is partitioned into nonoverlapping b ‐pixel groups (where, b = 3 or 4) which in succession are converted into transform domain using LhT in row‐major order. Secret bits are embedded into the LhT coefficients in varying proportions to achieve variable payload. Coefficient adjustment followed by the embedding process ensures minimum quality distortion. Inverse LhT is applied to regenerate b ‐pixel groups in the spatial domain. Results assure that incongruity between the cover pixels and stego‐pixels rises as the value of b increases. Hence, to achieve a high payload, smaller values of b are chosen. The proposed method yields higher peak signal to noise ratio values and payload compared to some recent methods found in the literature.