Subjective and Objective Quality Assessment of Transparently Encrypted JPEG 2000 Images

Transparent encryption has two main requirements, i.e. security and perceived quality. The perceptual quality aspect has never been thoroughly investigated. In this work, three variants to transparently encrypt JPEG2000 images are compared from a perceptual quality viewpoint. The assessment is based on subjective and objective quality assessment of the transparently encrypted images and if the requirements with respect to desired functionalities can be met by the respective techniques. In particular, we focus on the question if it is possible to predict the subjective quality of the encrypted (and attacked) images as given by the Mean Opinion Score (MOS) with state-of-the-art objective quality metrics. Additionally, we answer the question which objective quality measure is suited best to determine an image quality for which a certain subjective quality is required.