Data hiding technique for color images using pixel value differencing and chaotic map

The huge advance in information technology and communication has resulted in the growing usage of digital networks, which consequently handed an important role to information security. Steganography is the art of hiding secret message bits into different multimedia data to provide the transferred information with security against unauthorized access. Most techniques applying the pixel value differencing (PVD) approach depend on the sequential embedding manner that lacks security. This study proposes a method that uses a complex chaotic map to randomly choose the coefficients for embedding a secret message. First, the cover image is transformed through integer wavelet transform (IWT). The embedding process starts in the highest-frequency band of IWT and continues to the next subbands according to the message size. Adaptive embedding is then performed depending on the intensity variation between pixel pairs using PVD and least significant bit substitution. The nonsequential embedding performed using the chaotic map makes the method more secure. The experimental results show that the proposed technique achieves a high peak signal-to-noise ratio with an improved capacity compared with other techniques.