Shunichi Yonemura

Illuminant color estimation by hue categorization based on gray world assumption

This paper proposes a gray world assumption based method for estimating an illuminant color from an image by hue categorization. The gray world assumption hypothesizes that the average color of all the objects in a scene is gray. However, it is difficult to estimate an illuminant color correctly if the colors of the objects in a scene are dominated by certain colors. To solve this problem, our method uses the opponent color properties that the average of a pair of opponent colors is gray. Thus our method roughly categorizes the colors derived from the image based on hue and selects them one by one from the hue categories until selected colors satisfy the gray world assumption. In our experiments, we used three kinds of illuminants (i.e., CIE standard illuminants A and D65, and a fluorescent light) and two kinds of data sets. One data set satisfies the gray world assumption, and the other does not. Experiment results show that estimated illuminants are closer to the correct ones than those obtained with the conventional method and the estimation error for both using CIE standard illuminants A and D65 by our method are within the barely noticeable difference in human color perception.

Investigation of Web Usability Based on the Dialogue Principles

ISO 9241-110 standard provides user-interface design rules based on 7 dialogue principles. The priority of the principles varies depending on the characteristics of the tasks, the users, and the environments. We observed the behavior of middle-aged and older novice PC users when they performed some Web navigation tasks. We also pointed out some of the problems with usability, as discerned from the observations. We found that among the dialogue principles, self-descriptiveness is the most important. The observed problems, which were associated with the dialogue principles, suggest strategies for the enhancement of Web usability.

Disaster-response information sharing system based on cellular phone with GPS

In disasters, the victims must be provided with various bits of information. The information needed also changes with the situation. In this paper, we analyze the characteristics of such information and introduce an information sharing system. A prototype is developed around a cellular phone with GPS and its effectiveness is described.

Method of ecological interface design applied to interactive diagnosis support system

Abstract This paper proposes a procedure for designing ecological interfaces suitable for interactive diagnosis support systems based on the perspectives of work analysis and interface design proposed by Rasmussen [1, 2]. Several of the perspectives proposed by Rasmussen are chosen and concrete transformation paths are created for them. The effectiveness of the proposed procedure is confirmed by designing and testing a support system for interactive diagnosis.

Enhancing Abstract Imaginations of Viewers of Abstract Paintings by a Gaze Based Music Generation System

The purpose of abstract painters is to let viewers get the various images and abstract images. However, viewers who do not have enough knowledge of art, cannot easily get abstract images. The authors have proposed a music generation system that utilizes viewers’ gazes. It can be expected that the authors’ music generation system can prompt the viewer of abstract paintings to imagine abstract images, which the painter intended to express. This paper explores whether the authors’ music generation system can enhance abstract imaginations of persons who see abstract paintings, by subjective tests. Experiments using 19 subjects and eight abstract paintings were conducted for the two cases in which the subjects see the abstract paintings without hearing any music and while hearing the viewers’ gaze based music generated by the authors’ system. Experimental results imply that “hearing gaze based music” could enhance the viewers’ abstract imagination.

Inspiring Viewers of Abstract Painting by a Gaze Based Music Generation

This paper explores the effectiveness of prompting abstract paintings’ viewers’ inspiration and imagination by the authors’ gaze based music generation system. The authors’ music generation system detects the viewer’s gaze by a gaze detection equipment. At each of the gaze staying positions in the painting, the color of that point is converted to the sound so that as the gaze moves, music that consists of the converted time series sounds is generated. Experiments using six subjects and six abstract paintings were conducted for the three cases in which the subjects see the abstract paintings without hearing any music, while hearing pre-selected music and while hearing the viewers’ gaze based music generated by the authors’ system. The experimental results imply that “hearing gaze based music” could stimulate the viewers’ inspiration and imagination best, “hearing pre-selected music” second best, and “without music” third best.

Gray-world-assumption-based illuminant color estimation using color gamuts with high and low chroma

A new approach is proposed for estimating illuminant colors from color images under an unknown scene illuminant. The approach is based on a combination of a gray-world-assumption-based illuminant color estimation method and a method using color gamuts. The former method, which is one we had previously proposed, improved on the original method that hypothesizes that the average of all the object colors in a scene is achromatic. Since the original method estimates scene illuminant colors by calculating the average of all the image pixel values, its estimations are incorrect when certain image colors are dominant. Our previous method improves on it by choosing several colors on the basis of an opponent-color property, which is that the average color of opponent colors is achromatic, instead of using all colors. However, it cannot estimate illuminant colors when there are only a few image colors or when the image colors are unevenly distributed in local areas in the color space. The approach we propose in this paper combines our previous method and one using high chroma and low chroma gamuts, which makes it possible to find colors that satisfy the gray world assumption. High chroma gamuts are used for adding appropriate colors to the original image and low chroma gamuts are used for narrowing down illuminant color possibilities. Experimental results obtained using actual images show that even if the image colors are localized in a certain area in the color space, the illuminant colors are accurately estimated, with smaller estimation error average than that generated in the conventional method.

Study on accessibility of urgent message transmission service in a disaster

In this paper, the layer model of urgent message transmission service is proposed and the semantic level channels of communication inescapable when considering the accessibility of an urgent message are discussed.

Study of User Interface for Browsing Web Contents That Considers the Cognitive Features of Older Users

Web accessibility for old users has become a serious issue, especially in Japan. The problems involve cognitive as well as physical characteristics. Cognitive problems are well-handled by the metaphor approach, especially for older users when Web browsing. In order to investigate the impact of his approach, we conducted experiments with 11 old subjects and 10 young subjects. They were asked to search for a target in a Web site via the book metaphor interface and with a common Web browser interface. Although there were no differences in the task success rates or the task completion time between the two interfaces, there was a difference in the browsing time per Web page. The results of a questionnaire show that many old users prefer the metaphor interface. With the book interface, they selected the strategy of look and click because it lessens the demands placed on working memory.

Prompter . Based Creating Thinking Support Communication System That Allows Hand-Drawing

Research into creative thinking-support tools and communication is commonly focused on how to develop and share ideas between participants or with others. In this paper, we proposes a creative thinking support method that utilizes randomly generated visual prompter (black circle) image patterns (VP-patterns) and free hand-drawing and writing functions. Concepts and ideas of the research have been explained together with the development of the systems (CSP1 and CSP2). Experiments have been conducted in order to evaluate the potentials and effectiveness of the system. From the results, a tendency towards inspiring creative ideas by participants has been observed.