Efficient LSB substitution for interpolation based reversible data hiding scheme

Interpolation based reversible data hiding (IRDH) has created a new paradigm for data hiding research. This paper presents a new IRDH scheme with quadratic interpolation for digital image applications. A set of least significant bits (LSBs) are sought to be efficiently utilized in an adaptive manner for lower possible embedding distortion with higher embedding capacity. Particularly, a recent IRDH scheme employed a flag bit to track the form of embedded payload-bits (i.e., original or complement) in an embedded pixel. Whereas, we propose to utilize the correlation between the embeddable pixel and estimated versions of embedded pixel to embed one more data bit in place of the flag bit. Thus, our proposed scheme avoids using flag bit resulting in higher embedding capacity as demonstrated by our early experimental results. A significantly higher embedding capacity (i.e., about 30%–50% higher bpp) with reasonably better image quality (i.e., of about 1%–5% higher PSNR and SSIM values) is obtained for different values of capacity control parameter.