HDR Perception Challenges and Measurements in Cinema Environments
Francois Helt
The technical capabilities of moving picture projection are evolving. Higher dynamic range (HDR) is one of the most promising improvements to the cinema visual experience. However, various factors limit the effectiveness of technical developments. Physical limitations, such as optical diffusion and room reflectivity, have been shown to significantly affect scene contrast. Building on a previous model, this paper demonstrates a fully automatic room reflectivity measurement process. Diffusion measurement follows directly from the original model. One assumption of that model is the uniformity of reflection. This is only an approximation, and further work is necessary to assess how nonuniformity affects the perception of HDR. Therefore, a nonuniformity measurement method and simple descriptor are required and proposed. HDR image quality results should be evaluated from the point of view of cinema experience. The best course of action is to evaluate how optical diffusion, room reflectivity, and nonuniformity factors affect contrast sensitivity.