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The problem of reproducing high dynamic range images on devices with restricted dynamic range has gained a lot of interest in the computer graphics community. There exist various approaches to this issue, which span several research areas including computer graphics, image processing, color vision, physiological aspects, etc. These approaches assume a thorough knowledge of both the objective and subjective attributes of an image. However, no comprehensive overview and analysis of such attributes has been published so far.In this contribution, we present an overview about the effects of basic image attributes in HDR tone mapping. Furthermore, we propose a scheme of relationships between these attributes, leading to the definition of an overall image quality measure. We present results of subjective psychophysical experiments that we have performed to prove the proposed relationship scheme. Moreover, we also present an evaluation of existing tone mapping methods (operators) with regard to these attributes. Finally, the execution of with-reference and without a real reference perceptual experiments gave us the opportunity to relate the obtained subjective results.Our effort is not just useful to get into the tone mapping field or when implementing a tone mapping method, but it also sets the stage for well-founded quality comparisons between tone mapping methods. By providing good definitions of the different attributes, user-driven or fully automatic comparisons are made possible.

The separation of reflection components is an important issue in computer graphics, computer vision and imageprocessing. It provides useful information for the applications that need consistent object surface appearance, such as stereo reconstruction, visual recognition, tracking, objects re-illumination and dichromatic editing. In this paper we will present a brief survey of recent advances in separation of reflection components, also known as specularity (highlights) removal. Several techniques that try to tackle the problem from different points of view have been proposed so far. In this survey, we will overview these methods and we will present a critical analysis of their benefits and drawbacks.

Abstract-Recent advances in high dynamic range (HDR) capturing and display technologies attracted a lot of interest to HDR imaging. Many issues that are considered as being resolved for conventional low dynamic range (LDR) images pose new challenges in HDR context. One such issue is a lack of standards for HDR image compression. Another is the limited availability of suitable image datasets that are suitable for studying and evaluation of HDR image compression. In this paper, we address this problem by creating a publicly available dataset of 20 HDR images and corresponding versions compressed at four different bit rates with three profiles of the upcoming JPEG XT standard for HDR image compression. The images cover different scenes, dynamic ranges, and acquisition methods (fusion from several exposures, frame of an HDR video, and CGI generated images). The dataset also includes Mean Opinion Scores (MOS) for each compressed version of the images obtained from extensive subjective experiments using SIM2 HDR monitor.