Journal of the Japan society of photogrammetry and remote sensing
Online ISSN : 1883-9061
Print ISSN : 0285-5844
ISSN-L : 0285-5844
Volume 60, Issue 5
Displaying 1-14 of 14 articles from this issue
Preface
Original Papers
  • Genki TAKAHASHI, Hiroshi MASUDA
    2021 Volume 60 Issue 5 Pages 266-275
    Published: 2021
    Released on J-STAGE: November 01, 2022
    JOURNAL FREE ACCESS

    For road mapping, it is important to add labels to point clouds captured by the Mobile Mapping System (MMS). Some automatic labeling methods have been proposed so far. However, in our experiment, conventional labeling methods were not sufficiently accurate for actual point clouds measured in Japan. In this paper, we propose a high-performance classification method that combines the multi-scale features of point clouds, the MMS specific features and the features obtained from point clouds mapped on the 2D image. The accuracy of the proposed method was evaluated using actual MMS data, and it was confirmed that the proposed method could achieve high recognition rate generalization performance. Our method can improve the accuracy of automatic labeling of point clouds, and is expected to improve the efficiency of map maintenance, which is a social infrastructure.

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  • Katsuo OKAMOTO, Fumi TAKEMURA, Hidetomo TATSUMI, Hiroshi KOBAYASHI
    2021 Volume 60 Issue 5 Pages 276-281
    Published: 2021
    Released on J-STAGE: November 01, 2022
    JOURNAL FREE ACCESS

    Estimating damage to forests by strong winds is presented. In this study, a method to detect disaster-stricken forests by using the normalized difference vegetation index (NDVI) ratio before and after a disaster was developed. Chiba prefecture was selected as the test area. Many trees in Chiba prefecture were fallen due to strong winds of the Typhoon 15 (T1915) in 2019. One Sentinel-2 MSI dataset before T1915 and three after it were used for detecting wind fallen trees (WFTs). NDVI ratios in pure pixels of WFTs (WFT100%) were examined. NDVI ratios in pure pixels of no WFT (WFT0%) were also examined. Three linear interpolation expressions between WFT100% and WFT0% for MSI dataset after T1915 were developed to estimate the area ratio of WFTs in each mixel. 78% of WFTs detected by visible interpretation of aerial photographs were located in pixels with the area ratio of WFTs greater than 0%. In contrast, 93.4% of pixels with the area ratio of WFTs greater than 0% actually included WFTs. This method is useful to estimate the distribution of WFTs in the wide area.

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  • Junko SUGIMORI, Hirofumi CHIKATSU
    2021 Volume 60 Issue 5 Pages 282-286
    Published: 2021
    Released on J-STAGE: November 01, 2022
    JOURNAL FREE ACCESS

    Various kinds of cameras such as 360°camera, action cameras, smartphones, and drive recorders have been utilizing as an on-board cameras for the construction of the Intelligent Transport Systems. However, there are still problems with efficient imaging using on-board cameras. These problems are the influence of sunshine, and shadow or occlusion by the person or cars. On the other hand, the high sensitive functions of consumer grade digital cameras are amazingly increasing, and high sensitive imaging such as ISO409600 was achieved.

    In these circumstances, high sensitivity consumer grade digital cameras are enormously expected in imaging at night for solving the above problems, performance evaluations of high sensitivity consumer grade digital cameras are investigated in this paper.

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