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High Dynamic Range (HDR) and Wide Color Gamut (WCG) screens are able to render brighter and darker pixels with more vivid colors than ever. To assess the quality of images and videos displayed on these screens, new quality assessment metrics adapted to this new content are required. Because most SDR metrics assume that the representation of images is perceptually uniform, we study the impact of three uniform color spaces developed specifically for HDR and WCG images, namely, I C t C p , J z a z b z and H D R - L a b on 12 SDR quality assessment metrics. Moreover, as the existing databases of images annotated with subjective scores are using a standard gamut, two new HDR databases using WCG are proposed. Results show that MS-SSIM and FSIM are among the most reliable metrics. This study also highlights the fact that the diffuse white of HDR images plays an important role when adapting SDR metrics for HDR content. Moreover, the adapted SDR metrics does not perform well to predict the impact of chrominance distortions.

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High Dynamic Range (HDR) and Wide Color Gamut (WCG) screens are able to display images with brighter and darker pixels with more vivid colors than ever. Automatically assessing the quality of these HDR/WCG images is of critical importance to evaluate the performances of image compression schemes. In recent years, full-reference metrics, such as HDR-VDP-2, PU-encoding metrics, have been designed for this purpose. However, none of these metrics consider chromatic artifacts. In this paper, we propose our own full-reference quality metric adapted to HDR and WCG content that is sensitive to chromatic distortions. The proposed metric is based on two existing HDR quality metrics and color image features. A support vector machine regression is used to combine the aforementioned features. Experimental results demonstrate the effectiveness of the proposed metric in the context of image compression.

HDR (High Dynamic Range) and WCG (Wide Color Gamut) increase significantly quality of viewing experience by rendering impressive images and videos. Automatic assessing the quality of these HDR WCG images is one crucial objective in broadcast process. Full-reference HDR metrics have been designed in the last years to achieve this objective:HDR-VDP2, HDR-VQM, PU-encoding metrics. Recent studies have pointed out that HDR-VDP2 is one of the best metric. Unfortunately, HDR-VDP2 is quite complex to use due to numerous and sometimes hard-to-know parameters such as display emission spectrum, surround luminance and angular resolution. In this paper, we show that HDR-VDP2 does not require an accurate knowledge of the viewing condition parameters. For that, we not only test the impact of these parameters on existing image databases of subjective quality scores, but also we propose a new and complementary image database made with a different HDR display.