added 2 research items
This paper discusses the method to display the surfaces that exhibit sparkling and depth effects. Sparkling effects are usually caused by the metallic flakes diffused in the paint or coating. The novelty of the approach is to explicitly model the sparkle normal vectors for rendering using an embedded device that allows us perceive depth effects in virtual reality like application. Light redirected by flakes to miscellaneous directions causes random twinkling particle effect. Since, each eye perceives light from different direction, there are two distinct perceived images with random particles for each eye. This effect causes the particles to be perceived within certain depth. We have created an application which allows us to render sparkling effect with arbitrary distributions of sparkles.
In this article, we propose a methodology to measure the light reflectance of the material surface using a simple hardware set-up consisting of generally available mobile phones. The designed method incorporates two mobile phones to facilitate a time-consuming procedure. One device serves us as the light source and second one as the detector aperture. The user will move two phones with two hands above a measured sample, and the method will take into account only the correctly captured images. In this work, we propose a method to estimate the view direction of a phone camera and light source. A subsequent problem we solve is the fast Wi-Fi Direct device communication. We outline the enumeration of the bidirectional reflectance distribution function (BRDF) from the light intensities reflected off the planar samples. We present the satisfactory results measured with mobile phone cameras in a casual environment.
Humans recognize objects visually on the basis of material composition as well as shape. To acquire a certain level of photorealism, it is necessary to analyze, how the materials scatter the incident light. The key quantity for expressing the directional optical effect of materials on the incident radiance is the bidirectional reflectance distribution function (BRDF). Our work is devoted to the BRDF measurements, in order to render the synthetic images, mostly of the metallic paints. We measured the spectral reflectance off multiple paint samples then used the measured data to fit the analytical BRDF model, in order to acquire its parameters. In this paper we describe the methodology of the image synthesis from measured data. Materials such as the metallic paints exhibit a sparkling effect caused by the metallic particles scattered within the paint volume. Our analysis of sparkling effect is based on the processing of the multiple photographs. Results of analysis and the measurements were incorporated into the rendering process of car paint