Homomorphic-Encrypted Volume Rendering

TL;DR

This paper introduces a novel homomorphic encryption-based volume rendering method that allows secure remote visualization of sensitive data without trusting the server, ensuring privacy even if the server is compromised.

Contribution

It presents the first privacy-preserving volume rendering approach using homomorphic encryption that does not require trust in the server, enabling secure remote visualization.

Findings

Achieves secure volume rendering with minimal data leakage

Maintains high privacy standards even if the server is compromised

Provides performance and memory overhead analysis

Abstract

Computationally demanding tasks are typically calculated in dedicated data centers, and real-time visualizations also follow this trend. Some rendering tasks, however, require the highest level of confidentiality so that no other party, besides the owner, can read or see the sensitive data. Here we present a direct volume rendering approach that performs volume rendering directly on encrypted volume data by using the homomorphic Paillier encryption algorithm. This approach ensures that the volume data and rendered image are uninterpretable to the rendering server. Our volume rendering pipeline introduces novel approaches for encrypted-data compositing, interpolation, and opacity modulation, as well as simple transfer function design, where each of these routines maintains the highest level of privacy. We present performance and memory overhead analysis that is associated with our privacy-preserving scheme. Our approach is open and secure by design, as opposed to secure through obscurity. Owners of the data only have to keep their secure key confidential to guarantee the privacy of their volume data and the rendered images. Our work is, to our knowledge, the first privacy-preserving remote volume-rendering approach that does not require that any server involved be trustworthy; even in cases when the server is compromised, no sensitive data will be leaked to a foreign party.