Encryption-then-Compression Systems using Grayscale-based Image Encryption for JPEG Images
This addresses security for image transmission through untrusted channels like social media, but it appears incremental as it builds on existing EtC systems with specific improvements.
The paper tackles enhancing security in Encryption-then-Compression systems for JPEG images by proposing a block scrambling-based encryption scheme that uses grayscale images to reduce color information, and it demonstrates effectiveness against attacks like jigsaw puzzle solvers in experiments on Facebook and Twitter.
A block scrambling-based encryption scheme is presented to enhance the security of Encryption-then-Compression (EtC) systems with JPEG compression, which allow us to securely transmit images through an untrusted channel provider, such as social network service providers. The proposed scheme enables the use of a smaller block size and a larger number of blocks than the conventional scheme. Images encrypted using the proposed scheme include less color information due to the use of grayscale images even when the original image has three color channels. These features enhance security against various attacks such as jigsaw puzzle solver and brute-force attacks. In an experiment, the security against jigsaw puzzle solver attacks is evaluated. Encrypted images were uploaded to and then downloaded from Facebook and Twitter, and the results demonstrated that the proposed scheme is effective for EtC systems.