Image privacy protection with secure JPEG transmorphing

Abstract

Thanks to advancements in smart mobile devices and social media platforms, sharing photos and experiences has significantly bridged the authors’ lives, allowing them to stay connected despite distance and other barriers. Most approaches to protect image visual privacy focus on encrypting or permuting image data, which generate unreadable image or highly distorted visual effect and therefore may not be in users best interest from both usage and perception perspectives. In this study, the authors propose secure JPEG transmorphing, a framework for protecting image visual privacy in a secure, reversible, and highly flexible and personalised manner. Secure JPEG transmorphing allows one to apply arbitrary regional visual manipulation on image regions of interests (ROIs), while secretly preserving the information about the original ROIs in application segments (APPn markers) of the visually obfuscated JPEG image. Objective and subjective experiments have been performed and results indicate that the proposed protection scheme provides near lossless image reconstruction, controllable level of file size expansion, good degree of privacy protection and especially better subjective pleasantness.