Temporal Brightness Management for Immersive Content

Abstract

Modern virtual reality headsets demand significant computational resources to render high-resolution content in real-time. Therefore, prioritizing power efficiency becomes crucial, particularly for portable versions reliant on batteries. A significant portion of the energy consumed by these systems is attributed to their displays. Dimming the screen can save a considerable amount of energy; however, it may also result in a loss of visible details and contrast in the displayed content. While contrast may be partially restored by applying post-processing contrast enhancement steps, our work is orthogonal to these approaches, and focuses on optimal temporal modulation of screen brightness. We propose a technique that modulates brightness over time while minimizing the potential loss of visible details and avoiding noticeable temporal instability. Given a predetermined power budget and a video sequence, we achieve this by measuring contrast loss through band decomposition of the luminance image and optimizing the brightness level of each frame offline to ensure uniform temporal contrast loss. We evaluate our method through a series of subjective experiments and an ablation study, on a variety of content. We showcase its power-saving capabilities in practice using a built-in hardware proxy. Finally, we present an online version of our approach which further emphasizes the potential for low level vision models to be leveraged in power saving settings to preserve content quality.