In designing the color of outdoor industrial products such as cars and bridges, the optical balance of its model and background photograph (or each frame of the video sequence) needs to be maintained. To irradiate incident light onto a model, obtaining the accurate luminance, L C , of the sun and skylight distribution from all azimuths using luminance signal, E Y , but also video signal, (E R , E G , E B) is important. We propose how to measure skylight luminance distribution promptly with a highly accurate HDR (high dynamic range) according to video signal (E R , E G , E B), whose value is in an appropriate range each other, is guaranteed for different chromaticity of each pixel and luminance signal, E Y. Our method is unlike traditional HDR targeting the luminance distribution of skylight without considering appropriate range of individual video signal (E R , E G , E B) and excluding intensity of direct sunlight. That is, we use portable ND filters together with a digital camera fitted with a fisheye lens to meet the requirements mentioned above. We propose how to calculate 1) highly accurate luminance, L C , in an experiment and 2) the whole range of luminance, L C , of skylight in all azimuths including direct sunlight according to video signal (E R , E G , E B). Then, we display some field experimental results for showing the effectiveness of our method.
Member of JSCE, Dr. Eng., Sanei Co. Ltd. (3-13-26 Kagamiyama, Higashi-hiroshima, 739-0046 Japan) 3Member of JSCE, Assist. Prof., Hiroshima Inst. of Tech. (2 -1-1 Miyake, Saeei-ku, Hiroshima, 731-5193 Japan) It is a difficult task to automatically extract contour lines from a raster image topographic map and give each contour line its inherent elevation. In this paper, the authors propose an automatic contour line extraction algorithm based on the continuity among the contour lines. All of the paints on a contour line indicate the same elevation, the difference of elevations between every neighboring contour line is constant, and most wide contour lines have numeral arrays pointing out their inherent elevations. By employing the information of these features, the shapes and elevations of contour lines can be extracted and recognized. Usefulness of the proposed algorithm is demonstrated with several practical maps.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.