A reversible and lossless secret image sharing scheme with authentication for color images

With the increasing concern for public privacy protection, Secret Image Sharing (SIS) has garnered significant attention among researchers. The goal of SIS is to split a secret image into multiple shadows, rendering it unrecoverable unless a specific threshold of shares is obtained. However, these shadows typically appear as meaningless noise-like patterns, making them susceptible to attacks and raising suspicion when transmitted over traditional internet channels. Moreover, traditional SIS schemes often restrict image formats to binary, limiting their applicability. To address these limitations, we propose a reversible and lossless secret image sharing scheme with authentication specifically designed for color images. Our scheme generates noise-like shadows by combining original secret images and authentication images, which are then embedded into color images using an enhanced steganography method. During the recovery process, participants can extract the shares losslessly and complete the authentication phase without the need for a trusted third party. The authentication results can be easily verified by visual inspection. Ultimately, the qualified shadows are utilized to reconstruct the secret image, ensuring secure transmission of confidential image data. The efficacy and security of our proposed method are demonstrated via theoretical analysis and experimental results.