Real-time Tone Mapping

Tone-mapping is essential for photorealistic interactive applications, such as games or walkthroughs, as it allows for physically-based simulations of light to be rendered in a perceptually accurate manner. However, most currently existing tone-mapping operators fail to integrate well into real-time applications; their designs do not take temporal coherency into account. We demonstrate that it is possible to improve the temporal coherence of many tone-mapping operators using a generalised time-dependant framework designed for temporally varying HDR content. The framework also accounts for adaptation over time to the prevailing luminance in a scene, allowing an additional measure of psychophysical accuracy to be added to operators that was not present in their original design. The generalised framework is applied to both spatially uniform and spatially varying operators within an interactive application, which is used to conduct a study of their real-time performance; both in terms of efficiency and perceptual preference.