There are various kinds of learning systems in the world and quite a lot of them are using video sources. Also, those video sources have many kinds according to the content of learning and aim. In this paper, I'd like to describe the usability of learning systems by using a super high definition video source focusing on making
handling of video source using super high resolution. Furthermore, the future progress and present problems would be considered by proposing an on-demand learning system using a super high definition video source. The super high resolution here means 4K (4096x2160 dots).
Geometric registration between a virtual object and the real space is the most basic problem in augmented reality. Model-based tracking methods allow us to estimate three-dimensional (3-D) position and orientation of a real object by using a textured 3-D model instead of visual marker. However, it is difficult to apply existing model-based tracking methods to the objects that have movable parts such as a display of a mobile phone, because these methods suppose a single, rigid-body model.
In this research, we propose a novel model-based registration method for multi rigid-body objects. For each frame, the 3-D models of each rigid part of the object are first rendered according to estimated motion and transformation from the previous frame. Second, control points are determined by detecting the edges of the rendered image and sampling pixels on these edges. Motion and transformation are then simultaneously calculated from distances between the edges and the control points. The validity of the proposed method is demonstrated through experiments using synthetic videos.
Two methods are described to accurately estimate diffuse and specular reflectance parameters for colors, gloss
intensity and surface roughness, over the dynamic range of the camera used to capture input images. Neither
method needs to segment color areas on an image, or to reconstruct a high dynamic range (HDR) image. The
second method improves on the first, bypassing the requirement for specific separation of diffuse and specular
reflection components. For the latter method, diffuse and specular reflectance parameters are estimated separately,
using the least squares method. Reflection values are initially assumed to be diffuse-only reflection
components, and are subjected to the least squares method to estimate diffuse reflectance parameters. Specular
reflection components, obtained by subtracting the computed diffuse reflection components from reflection
values, are then subjected to a logarithmically transformed equation of the Torrance-Sparrow reflection model,
and specular reflectance parameters for gloss intensity and surface roughness are finally estimated using the least
squares method. Experiments were carried out using both methods, with simulation data at different saturation
levels, generated according to the Lambert and Torrance-Sparrow reflection models, and the second method,
with spectral images captured by an imaging spectrograph and a moving light source. Our results show that
the second method can estimate the diffuse and specular reflectance parameters for colors, gloss intensity and
surface roughness more accurately and faster than the first one, so that colors and gloss can be reproduced more
efficiently for HDR imaging.
To overcome shortcomings of digital image, or to reproduce grain of traditional silver halide photographs, some
photographers add noise (grain) to digital image. In an effort to find a factor of preferable noise, we analyzed how a
professional photographer introduces noise into B&W digital images and found two noticeable characteristics: 1) there is
more noise in mid-tones, gradually decreasing in highlights and shadows toward the ends of tonal range, and 2)
histograms in highlights are skewed toward shadows and vice versa, while almost symmetrical in mid-tones. Next, we
examined whether the professional's noise could be reproduced. The symmetrical histograms were approximated by
Gaussian distribution and skewed ones by chi-square distribution. The images on which the noise was reproduced were
judged by the professional himself to be satisfactory enough. As the professional said he added the noise so that "it
looked like the grain of B&W gelatin silver photographs," we compared the two kinds of noise and found they have in
common: 1) more noise in mid-tones but almost none in brightest highlights and deepest shadows, and 2) asymmetrical
histograms in highlights and shadows. We think these common characteristics might be one condition for "good" noise.
Since commercial image detectors, such as charge-coupled device (CCD) cameras, have a limited dynamic range, it is difficult to obtain images that really are unsaturated, as a result of which the reflectance parameters may be inaccurately estimated. To solve this problem, we describe a method to estimate reflectance parameters from saturated spectral images. We separate reflection data into diffuse and specular components at 5-nm intervals between 380nm and 780nm for each pixel of the spectral images, which are captured at different incident angles, and estimate the diffuse reflectance parameters by applying the Lambertian model to the diffuse components. To estimate the specular reflectance parameters from the specular components, we transform the Torrance-Sparrow equation to a linear form, assuming Fresnel reflectance is constant. We then estimate specular parameters for intensity of the specular reflection and standard deviation of the Gaussian distribution, using the least squares method from unsaturated values of the specular components. Since Fresnel reflectance contributes to the physically based Torrance-Sparrow model in computer graphics and vision, we estimate both the Fresnel reflectance in terms of the Fresnel equation for the incident angle and the refractive index of the surface for dielectric materials, which varies with wavelength. We carried out experiments with measured data, and with simulated specular components at different saturation levels, generated according to the Torrance-Sparrow model. Our experimental results reveal that the diffuse and specular reflectance parameters are estimated with high quality.
We propose a new framework for interactive Augmented Reality (AR) and Mixed Reality (MR) representation using both visible and invisible projection onto physical target objects. Projection-based approach for constructing AR/MR uses physical objects such as walls, books, plaster ornaments and whatever the computer generated contents can be optically projected onto. Namely, projection makes it possible to use real objects as displays.
We mainly focus on capturing and utilizing the 3D shape of the object surface, whose information allows the AR/MR system to take into account the visual consistency when merging the physical and rendered objects. 3D shape data of the object can be used to compensate the distortion caused by the difference between positions of projectors and the viewer. The other advantage is the capability to generate proper visual occlusion between physical and virtual objects so that they seem to coexist in front of the viewer.
What we demonstrate in this study is to employ near-infrared pattern projection for triangulation so that scanning and updating the geometry data of the object is automatically performed in background process, thus parallel processing to provide AR/MR representation can be achieved according to dynamic physical geometry changes.
We propose a new technique to reproduce faithfully both the color and the gloss of an object on a computer, using multispectral images. An imaging spectrograph equipped with a monochrome charge-coupled device (CCD) camera is fixed in front of the target object. Multispectral images of a linear portion of the object's surface are captured at suitable intervals by a measuring system which comprises a light source orbiting the target object. To obtain spectral images for the whole surface, the target object is also rotated. The reflection is separated into diffuse and specular components, according to the dichromatic reflection model, and the diffuse parameters are estimated at 5-nm intervals between 380nm and 780nm for each pixel. Since the CCD camera used to capture images has a limited dynamic range, we suppose that the specular reflection is independent of wavelength for the dielectrics, and that the specular reflections are saturated, although some of them can be non-saturated. We adopt the Torrance-Sparrow reflectance model for the specular reflection, and estimate the specular parameters using the least squares method for each pixel. Our experimental results reveal that the diffuse parameters for the color and the specular parameters for the gloss of the target object are satisfactorily estimated.
In this paper, we propose new measurement technique of whole three dimensional shape for small moving objects. The proposed measurement system is very simple structure with the use of a CCD camera that installed a fish-eye lens and a cylinder that coating mirror inside. The CCD camera is set on the top side of the cylinder, and its optical axis is set to the center of cylinder. A captured image includes two types information. One is direct view of the target, the other is reflected view. These two information are used for measuring the shape of target by means of stereo matching. This proposed method can acquire the shape of target using only single image, so we can obtaine the three dimensional shape with the moving with the use of image sequence.
Wearable 3D measurement realizes to acquire 3D information of an objects or an environment using a wearable computer. Recently, we can send voice and sound as well as pictures by mobile phone in Japan. Moreover it will become easy to capture and send data of short movie by it. On the other hand, the computers become compact and high performance. And it can easy connect to Internet by wireless LAN. Near future, we can use the wearable computer always and everywhere. So we will be able to send the three-dimensional data that is measured by wearable computer as a next new data. This paper proposes the measurement method and system of three-dimensional data of an object with the using of wearable computer. This method uses slit light projection for 3D measurement and user’s motion instead of scanning system.
Under growth of request for energy saving, city planners should consider efficiency of energy consumption from the beginning. Diversified analysis of end-use energy consumption is indispensable for exploration of desirable energy system in urban area. When the visualization is available on the Internet, the city planners can discuss freely on given plans on the Internet and can ask for the help and comments of certain learned people. This paper proposes a VR-based interactive visualization system utilizing hyperlink function of VRML. The proposed visualization relates end-use energy consumption with consumers' geometrical arrangements and nests sets of visualizations. The city planners can observe them in a virtual environment over the Internet. The proposed system was applied to a set of end-use electric power consumption data of a certain area. Experimental results clear that the visualization lets users comprehend a trend of end-user and characteristics of each consumer.