An application of a commercial 3D haptic device, PHANToM Omni, to personal authentication system was proposed, in which handwriting identification scheme was performed with the letter drawn on an invisible graphic tablet that was generated by the device as a virtual canvas. In this paper, an investigation was made for better performance on the character used for authentication and the physical condition of handwriting by the device.
Simulation of deformation and fracturing of objects has been widely studied in computer graphics. One of the main goals is to accomplish such simulations with little computational cost in a numerically stable way. The proposed method presents a fast simulation technique that approximates an object with a lattice, manages the lattice with a hierarchical data structure and a lattice in a different level of the hierarchy is used according to the deformed shape of the object and the condition of fracturing. By applying a virtual force derived geometrically to each lattice point, the present method can calculate deformation and fracturing of objects stably. While the existing method cannot keep the stiffness of the object in different levels of the hierarchy, the present method modifies the computation so that the stiffness is maintained uniform by introducing a stiffness parameter that does not depend on the hierarchy. This extension enables visually more plausible animations of deformation and fracturing than previous methods.
Recently, many researchers have focused on the technique called non-photorealistic rendering. By using the technique, images that are similar to hand-drawn pictures can be generated automatically. Especially, methods for creating cartoon style pictures are often utilized since the methods can significantly reduce the word load required in the traditional manual animation production process. In this research, we propose an interactive method for cartoon rendering of smoke. In our system, the motions and densities of the smoke are calculated by using the computational fluid dynamics. For the cartoon rendering of the smoke, particles are generated in the flow. For each particle, the user can attach an arbitrary density distribution to determine the small-scale details of the smoke shape. This makes it possible to generate smoke with the desired details. The small-scale details can be interactively edited by a sketch-based user interface.
In ubiquitous network society, the information of mobility nodes such as pedestrians with cell phones is very useful for network configuration, communication control and so on. In this paper, we propose an approach to estimate the number of pedestrians using surveillance video footage from a stationary camera. The proposed approach extracts variation regions from video snapshots by using background difference and frame difference, and estimates the number of pedestrians from the area of the extracted region, using conversion algorithm constructed from the statistical data. We evaluate the efficacy of the proposed approach by comparison the estimated values with the true values and find that the mean difference in the number of pedestrians is within 0.36.
The study on the recovery of spectral reflectances through the use of an image data has been done actively for the reproduction of a color image under a variety illuminations by using color appearance models. Since spectral reflectances are unique to objects which are independent on an illumination and on an image acquisition device, the accurate recovery of spectral reflectances is very important. The authors have already shown that the estimation of noise variance in an image acquisition system by the use of spectral reflectances of learning samples is very useful to recover spectral reflectances of test samples accurately from the test sample's image data by the use of the Weiner estimation with the estimated noise variance. In this paper, the spectral reflectances of test samples were recovered when different illuminations were used for image acquisition of learning and test samples. It is shown that recovery performance of our model is more accurate than the regression model, which is usually used, and theoretical discussion is given for this result.
People who have suffered mild brain damages due to senescence or cerebrovascular illness may look ordinary at first sight. however it is difficult for them to lead a normal social life. Often, the requirement for constant care and attention creates a burden for their family members. A possible method for reducing this stress is to enable the disadvantaged person to participate in a networked community. However, brain damaged people cannot operate a personal computer. In Networked Interaction Therapy Project, we are investigating novel interfaces which will allow the mildly brain-damaged to participate in networked communication without having to operate a computer.