An Enhanced Image Steganography Approach in DWT Transform Area using LSB for Secure Data Transmission

Abstract

The rising cases of cyber threats have necessitated the need to give greater emphasis on steganography methods of secure digitally communicating. A better method of image steganography that incorporates Discrete Wavelet Transform (DWT) with Least Significant Bit (LSB) substitution and RSA encryption has been introduced in the study to counter the weaknesses in embedding spatial domain techniques. The hybrid scheme initially employs the RSA cryptography to encrypt a message which forms the part of secret messages, and subsequently, encodes cover images between RGB to YCbCr color space in order to capitalize on the perception properties of a human visual system. The DWT decomposition and the LSB replacement secure the encrypted data in the frequency domain sub bands, which ensures a high rate of statistical and visual detection attacks. The approach considered three important steganography requirements namely security (by cryptographic encryption), imperceptibility (by frequency domain embedding and color space optimization), and robustness in image processing attacks. Performance analysis proves that it shows promising results in covering capacity, visual clarity in terms of Peak Signal-to-Noise Ratio (PSNR) and resistance to over traditional LSB approaches and thus provides an efficient remedy to steganography requirements in many contemporary security situations.