Colorization of Diffuse Reflection Component of a Monochrome Image

Abstract This paper presents a non-line-of-sight technique to estimate the position and temperature of an occluded object from a camera via reflection on a wall. Because objects with heat emit far infrared light with respect to their temperature, positions and temperatures are estimated from reflections on a wall. A key idea is that light paths from a hidden object to the camera depend on the position of the hidden object. The position of the object is recovered from the angular distribution of specular and diffuse reflection component, and the temperature of the heat source is recovered from the estimated position and the intensity of reflection. The effectiveness of our method is evaluated by conducting real-world experiments, showing that the position and the temperature of the hidden object can be recovered from the reflection destination of the wall by using a conventional thermal camera.

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On the Estimation of the Luminance Distribution by the Diffuse Reflection Component of an Object's Surface and Shape Measurement-Analysis by the Numerical Experiment-

Journal of Light & Visual Environment ◽

10.2150/jlve.28.1 ◽

2004 ◽

Vol 28 (1) ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Naotaka IKEMOTO ◽

Minoru ISOMURA

Keyword(s):

Numerical Experiment ◽

Diffuse Reflection ◽

Shape Measurement ◽

Luminance Distribution ◽

Measurement Analysis ◽

Reflection Component

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Development of a System to Measure the Optical Properties of Facial Skin using a 3D Camera and Projector

Journal of Imaging Science and Technology ◽

10.2352/j.imagingsci.technol.2021.65.5.050403 ◽

2021 ◽

Author(s):

Kumiko Kikuchi ◽

Shoji Tominaga ◽

Jon Y. Hardeberg

Keyword(s):

Optical Properties ◽

Diffuse Reflection ◽

Specular Reflection ◽

Three Dimensional ◽

Depth Image ◽

Facial Skin ◽

Subsurface Scattering ◽

Surface Reflection ◽

Reflection Model ◽

Reflection Component

We have developed a system to measure both the optical properties of facial skin and the three-dimensional shape of the face. To measure the three-dimensional facial shape, our system uses a light-field camera to provide a focused image and a depth image simultaneously. The light source uses a projector that produces a high-frequency binary illumination pattern to separate the subsurface scattering and surface reflections from the facial skin. Using a dichromatic reflection model, the surface reflection image of the skin can be separated further into a specular reflection component and a diffuse reflection component. Verification using physically controlled objects showed that the separation of the optical properties by the system correlated with the subsurface scattering, specular reflection, or diffuse reflection characteristics of each object. The method presented here opens new possibilities in cosmetology and skin pharmacology for measurement of the skin’s gloss and absorption kinetics and the pharmacodynamics of various external agents.

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Effects of Sample Dilution and Particle Size/Morphology on Diffuse Reflection Spectra of Carbohydrate Systems in the Near- and Mid-Infrared. Part I: Single Analytes

Applied Spectroscopy ◽

10.1366/0003702934066965 ◽

1993 ◽

Vol 47 (6) ◽

pp. 687-694 ◽

Cited By ~ 50

Author(s):

Jill M. Olinger ◽

Peter R. Griffiths

Keyword(s):

Particle Size ◽

Near Infrared ◽

Diffuse Reflection ◽

Specular Reflection ◽

Wheat Starch ◽

Reflection Spectra ◽

Mid Infrared ◽

Large Particles ◽

Reflection Component ◽

Sucrose Crystals

The mid- and near-infrared diffuse reflection spectra of three carbohydrates—microcrystalline cellulose, wheat starch, and sucrose—are examined to determine whether dilution is necessary in either spectral region in order to avoid the effects of specular reflection. As expected, it was found that dilution was not necessary to obtain valid diffuse reflection spectra of samples in the near-infrared, but that dilution was necessary for measuring mid-infrared diffuse reflection spectra free of the effects of specular reflection. The effects of particle size and sample morphology were investigated for sucrose crystals up to 2 mm in dimension. Depending upon the particle size and orientation, the effects of specular reflection can be observed in both near- and mid-infrared diffuse reflection spectra of sucrose. Surface roughness can allow a diffuse reflection component to be measured in the spectra of very large particles where a specular reflection mechanism would typically be expected to predominate.

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