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In this paper we present a new technique for the display of High Dynamic Range (HDR) images on Low Dynamic Range (LDR) displays. The described process has three stages. First, the input image is segmented into luminance zones. Second, the tone mapping operator (TMO) that performs better in each zone is automatically selected. Finally, the resulting tone(More)
In recent years inverse tone mapping techniques have been proposed for enhancing low-dynamic range (LDR) content for a high-dynamic range (HDR) experience on HDR displays, and for image based lighting. In this paper, we present a psychophysical study to evaluate the performance of inverse (reverse) tone mapping algorithms. Some of these techniques are(More)
When colourimetrically characterising a high dynamic range display (HDR) built from an LCD panel and an LED backlight one is faced with several problems: the channels may not be constant; they may not be independent and there may be a significant radiant output at the black level. But crucially, colour transforms are underdetermined, which means that the(More)
In the last few years, researchers in the field of High Dynamic Range (HDR) Imaging have focused on providing tools for expanding Low Dynamic Range (LDR) content for the generation of HDR images due to the growing popularity of HDR in applications, such as photography and rendering via Image-Based Lighting, and the imminent arrival of HDR displays to the(More)
In this paper, we investigate how controlled changes to image properties and orientation affect eye movements for repeated viewings of images of natural scenes. We make changes to images by manipulating low-level image content (such as luminance or chromaticity) and/or inverting the image. We measure the effects of these manipulations on human scanpaths(More)
The classical approach to converting colour to greyscale is to code the luminance signal as a grey value image. However, the problem with this approach is that the detail at equiluminant edges vanishes, and in the worst case the greyscale reproduction of an equiluminant image is a single uniform grey value. The solution to this problem, adopted by all(More)
In the real world we can find large intensity ranges: the ratio from the brightest to the darkest part of the scene can be of the order of 10000 to 1. Since most of our electronic displays have a limited range of around 100 to 1, the last 20 years has seen much work done to develop different algorithms that compress the actual dynamic range of an image to(More)
We explore the relative utility of shape from shading and binocular disparity for depth perception. Ray-traced images either featured a smooth surface illuminated from above (shading-only) or were defined by small dots (disparity-only). Observers judged which of a pair of smoothly curved convex objects had most depth. The shading cue was around half as(More)
Image gradients--smooth changes in color and luminance--may be caused by intrinsic surface reflectance properties or extrinsic illumination phenomena, including shading, shadowing, and inter-reflections. In turn, image gradients may provide the visual system with information concerning the origin of these factors, such as the orientation of surfaces with(More)