Temporal Coherency in Video Tone Mapping, A Survey

High Dynamic Range (HDR) video acquisition and display is now achievable thanks to recent advances in the HDR field. Tone Mapping Operators (TMOs) convert HDR images to Low Dynamic Range (LDR) ones. However, these operators do not take into account the temporal correlation present in a video sequence. We first present in this article, two main issues that arise when dealing with video tone mapping: flickering and temporal brightness incoherency. Flickering corresponds to rapid changes of either the tone map curve or the scene content. As for brightness incoherency, it occurs when tone mapping frames of a video sequence separately. We then propose a survey of the techniques that solve these issues. Results show that while some issues have been well studied and solved, others still need further work.