Tone mapping

About: Tone mapping is a research topic. Over the lifetime, 1713 publications have been published within this topic receiving 48490 citations.

Tone mapping image quality objective evaluation method based on global characteristic

Abstract: The invention discloses a tone mapping image quality objective evaluation method based on a global characteristic, wherein the method comprises two processes of a training period and a testing period. Influences of a natural scene statistics characteristic and a color statistics characteristic to tone mapping are considered. A global characteristic vector of a tone mapping image is extracted. Then support vector regression is utilized for training the global characteristic vectors of all tone mapping images in a training image set, thereby constructing a quality predication model. In the testing period, through calculating the global characteristic vector of the tone mapping image for testing, and a quality objective evaluation predicated value of the tone mapping image is obtained through predicating according to the quality predication model which is constructed in the training period. Because the obtained global characteristic vector information has relatively high stability and furthermore can well reflect the quality change condition of the tone mapping image, correlation between an objective evaluation result and subjective perception is effectively improved.

Environment-Aware Supervised HDR Tone Mapping

Abstract: Embodiments of the present disclosure provide techniques for environment aware supervised HDR tone mapping. According to those techniques, responsive to metadata provided with HDR source video data, the received metadata may be compared to sensor date representing viewing conditions at a display device. Tone mapping corrections to the HDR source video data may be derived from the comparison of the received metadata to the sensor data. The HDR source video data may be altered based on the tone mapping corrections. The altered HDR source video data may be used to drive the display device.

Gamut mapping in a high-dynamic-range color space

Abstract: In this paper, we present a novel approach of tone mapping as gamut mapping in a high-dynamic-range (HDR) color space. High- and low-dynamic-range (LDR) images as well as device gamut boundaries can simultaneously be represented within such a color space. This enables a unified transformation of the HDR image into the gamut of an output device (in this paper called HDR gamut mapping). An additional aim of this paper is to investigate the suitability of a specific HDR color space to serve as a working color space for the proposed HDR gamut mapping. For the HDR gamut mapping, we use a recent approach that iteratively minimizes an image-difference metric subject to in-gamut images. A psychophysical experiment on an HDR display shows that the standard reproduction workflow of two subsequent transformations – tone mapping and then gamut mapping – may be improved by HDR gamut mapping.

An improved tone mapping algorithm for High Dynamic Range images

Abstract: Real world scenes contain a large range of light intensities. To adapt to display device, High Dynamic Range (HDR) image should be converted into Low Dynamic Range (LDR) image. A common task of tone mapping algorithms is to reproduce high dynamic range images on low dynamic range display devices. In this paper, a new tone mapping algorithm is proposed for high dynamic range images. Based on the probabilistic model is proposed for high dynamic image's tone reproduction, the proposed method uses a logarithmic normal distribution instead of normal distribution. Therefore, the algorithm can preserve visibility and contrast impression of high dynamic range scenes in the common display devices. Experimental results show the superior performance of the app roach in terms of visual quality.

Visual analysis of the computer simulation for both imaging and non-imaging optical systems

Abstract: Typical results of the optic simulation are images generated on the virtual sensors of various kinds. As a rule, these images represent two-dimensional distribution of the light values in Cartesian coordinates (luminance, illuminance) or in polar coordinates (luminous intensity). Using the virtual sensors allows making the calculation and design of different kinds of illumination devices, providing stray light analysis, synthesizing of photorealistic images of three-dimensional scenes under the complex illumination generated with optical systems, etc. Based on rich experience in the development and practical using of computer systems of virtual prototyping and photorealistic visualization the authors formulated a number of basic requirements for the visualization and analysis of the results of light simulations represented as two-dimensional distribution of luminance, illuminance and luminous intensity values. The requirements include the tone mapping operators, pseudo color imaging, visualization of the spherical panorama, regression analysis, the analysis of the image sections and regions, analysis of pixel values, the image data export, etc. All those requirements were successfully satisfied in designed software component for visual analysis of the light simulation results. The module "LumiVue" is an integral part of "Lumicept" modeling system and the corresponding plug-in of computer-aided design and support for CATIA product. A number of visual examples of analysis of calculated two-dimensional distribution of luminous intensity, illuminance and luminance illustrate the article. The examples are results of simulation and design of lighting optical systems, secondary optics for LEDs, stray light analysis, virtual prototyping and photorealistic rendering.