I. Introduction
Visual security authentication, e.g., face recognition [1]–[3] and fingerprint identification [4], has achieved considerable advances in recent years. Its wide application also poses a challenge that such sensitive data as face and fingerprint need to be protected. High-capacity image steganography, which generates a container image to conceal a secret image in a cover image, is an elegant and widespread technique to address this issue [5]. Previous methods [6], [7] focus on the protection of secret images during transmission. Consequently, they run a risk of visual privacy leakage after restoration: once the receiver is under attack, secret images can be stolen. To this end, we propose a framework, called Multitask Identity-Aware Image Steganography (MIAIS), to perform recognition directly on container images without restoring secret images, as shown in Fig. 1.
Comparison of previous image steganography methods and ours. An image steganography method generates a container image by hiding a secret image in a cover image. The container image would be transferred from a sender to a receiver. Our difference from previous methods lies in the processing of container images. Top: Previous methods restore secret images from container images for recognition, which raises a risk of privacy leakage. Bottom: Our framework performs recognition directly on container images.