Development and evaluation of gamut extension algorithms

In recent years, new display technologies have emerged that are capable of producing colors that exceed the color gamut of broadcast standards. On the other hand, most video content currently remains compliant with the EBU standard and as such, there is a need for color mapping algorithms that make optimal use of the wider gamut of these new displays. To identify appropriate color mapping strategies, we have developed, implemented, and evaluated several approaches to gamut extension. The color rendering performance and robustness to different image content of these algorithms were evaluated against a reference (true-color) mapping. To this end, two psychophysical experiments were conducted using a simulated and actual wide-gamut display. Results show that the preferred algorithm had a dependency on image content, especially for images with skin tones. In both experiments, however, there was preference shown for the algorithm that balances chroma and lightness modulations as a function of the input lightness. The newly designed extension algorithms consistently outperformed true-color mapping, thus confirming the benefit of appropriate mapping on wide-gamut displays. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 443–451, 2009