Secured Communication Method using Visual Secret Sharing Scheme for Color Images

Protecting Personally identifiable information (PII) and Protected health Information (PHI) is always challenging in this digital era. An ongoing global pandemic of coronavirus disease 2019 called as coronavirus pandemic (COVID-19), has forced people towards digital transaction of data all over the world. Telemedicine allows health care service providers to evaluate, diagnose and treat patients at a distance using telecommunications tools and technology. Patients communicate the medical reports, medical images and related documents by email. Data that carries PHI information, is communicated via public networks in the form of image and are vulnerable. An effective encryption technique is always in need to transfer such information securely. Visual Secret Sharing (VSS) scheme is an efficient encryption scheme that decodes the image by dividing into number of shares. Individual shares do not reveal any secret and stacking of all shares can reveal the secret image. In this article, Semantic Visual Secret Sharing scheme (SVSS) is proposed, which can be applicable for both gray-scale and color images. In this SVSS, the secret color image I is converted into semantic image SI by reducing the pixel errors. This SI decreases the encoding complexity without affecting the quality. The proposed SVSS avoids pixel expansion issues faced by traditional VSS schemes. Also, the Peak Signal-to-Noise Ratio (PSNR) value of the reconstructed secret color image shows better quality of the reconstructed secret image. The pixel errors that get introduced during share generation phase is reduced. The experimental result shows the effectiveness of the proposed SVSS and ensures secure transmission.