Invertible secret image sharing for gray level and dithered cover images

Secret image sharing approaches have been extended to obtain covers from stego images after the revealing procedure. Lin et al.’s work in 2009 uses modulus operator to decrease the share image distortion while providing recovery of original covers. Their work use gray level or binary image as cover. Stego images have approximately 43 dB and 38 dB PSNR for gray level and binary covers respectively. Lin et al.’s work in 2010 provides enhanced embedding capacity but does not support binary covers. Gray level covers’ PSNR is reported approximately 40 dB. The proposed method enhances the visual quality of stego