Joint Data Hiding and Partial Encryption of Compressive Sensed Streams

TL;DR

This paper introduces a novel method combining data hiding and partial encryption for compressive sensing streams, enabling secure, real-time measurement protection suitable for single-pixel cameras with controlled image distortion.

Contribution

It presents a new on-the-fly data hiding and encryption technique for CS streams that reduces processing delay and allows sequential measurement acquisition.

Findings

Embedding 10 levels causes approximately 18 dB image distortion.

The method enables real-time secure measurement insertion without buffering.

Reversible data hiding is adapted for CS measurement statistics.

Abstract

The paper proposes a method to secure the Compressive Sensing (CS) streams. It consists in protecting part of the measurements by a secret key and inserting the code into the rest. The secret key is generated via a cryptographically secure pseudo-random number generator (CSPRNG) and XORed with the measurements to be inserted. For insertion, we use a reversible data hiding (RDH) scheme, which is a prediction error expansion algorithm, modified to match the statistics of CS measurements. The reconstruction from the embedded stream conducts to visibly distorted images. The image distortion is controlled by the number of embedded levels. In our tests, the embedding on 10 levels results in $\approx 18 dB $ distortion for images of 256x256 pixels reconstructed with the Fast Iterative Shrinkage-Thresholding Algorithm (FISTA). A particularity of the presented method is on-the-fly insertion that makes it appropriate for the sequential acquisition of measurements by a Single Pixel Camera. On-the-fly insertion avoids the buffering of CS measurements for a subsequent standard encryption and generation of a thumbnail image.