AutoSens Tutorial 1: The Three Goals of HDR
High Dynamic Range (HDR) imaging is a continuously evolving part of Imaging. More than twenty years ago HDR started to be popular with the seminal paper of Debevec and Malik proposing multiple exposures to attempt to capture a wider range of scene information
Ten-plus years ago interest evolved to recreating HDR scenes by integrating widely-used LCD with LED illumination (Helge Seetzen’s Brightsides Displays). Today, the evolution continues in the current sales of HDR televisions using OLED and Quantum Dot technologies. As well, standards for HDR video media formats remain an active area of research.
This tutorial reviews the science and technology underlying the evolution of HDR imaging from silver-halide photography to HDR TVs. HDR technology is a complex problem controlled by optics, signal-processing and visual limits. The solution depends on its goal.
After a detailed description of the dynamic range problem in image acquisition, this course focuses on standard methods of creating and manipulating HDR images focusing on the different possible goals of the HDR pipeline: reproducing light field, reproducing appearance, improving image aesthetic and visibility. For each goal a careful analysis of characteristics, limits and ground truth will be presented. The course aims at replacing myths with measurements about the limits of accurate camera acquisition (range and color) and the usable range of light for displays presented to human vision. It discusses the principles of tone rendering and the role of HDR spatial comparisons.
- HDR Reproduction History
- HDR principles, devices and techniques
- The 3 HDR goals
- Reproducing original HDR scene: Capture Challenges
- Rendering Appearance for LDR display: Display Challenges
- Improving image aesthetic and visibility: HDR in Human Vision
- Goals, ground-truths and assessment criteria for HDR applications