With the advent of High Dynamic Range (HDR) and Wide Color Gamut (WCG) displays, a new need to do conversions of color volume and gray scale has arrived. That is because there will be an increasing variety of content graded in various color gamuts and dynamic ranges (range or black to white levels) as well as displays with an even bigger range of color volume capabilities and dynamic range.
For example, HDR/WCG grading can be done to the DCI-P3 or 2020 color gamut standards and the dynamic range can have various black levels and peak luminance levels (600, 1000, 2000 and 4000 cd/m²). Playback of this content on displays with 709, P3 or a wide color gamut is possible. This can be coupled with displays offering 300 to 1000 cd/m² of brightness and various black levels as well.
As you can see, making tone-mapping transformations that preserve the original look and feel of the content across multiple displays is extremely challenging and offers much room for differentiation in the market.
To aid in evaluating the robustness of these tone mapping operators, a group of well respected image professionals have teamed up to offer new content specifically produced to aim in evaluating these transforms on HDR displays.
Authors of the content include: Jan Fröhlich, Stefan Grandinetti, Bernd Eberhardt, Simon Walter, Andreas Schilling, Harald Brendel. Four pieces of content are available for non-educational use (free) or for commercial use (with a licence).
The content includes scenic and documentary sequences with a dynamic range of up to 18 stops. The scenes are staged using professional film lighting, make-up and set design to enable the evaluation of image and material appearance. To address challenges for HDR-displays and temporal tone mapping operators, the sequences include highlights entering and leaving the image, brightness changing over time, high contrast skin tones, specular highlights and bright, saturated colors. HDR-capture is carried out using two cameras mounted on a mirror-rig. To achieve a cinematic depth of field, digital motion picture cameras with Super-35mm size sensors are used.
Available content includes:
- Reconstructed scene radiance in Alexa-Wide-Gamut color space (80GB OpenEXR files)
- All clips color graded for Rec.2020 primaries and 0.005-4000cd/m² luminance (189GB TIFF files)
- Wide color gamut digital cinema package comparing Rec.2020, P3-D65 and Rec.709 (10GB DCP)
- Short teaser sequences available for standardization
To learn more and to download the content, go to: https://hdr-2014.hdm-stuttgart.de/