| Presentation | 2021-10-08 A Study on Contrast Enhancement of Images for SfM Kazuaki Takahashi, Masaaki Fujiyoshi, |
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| PDF Download Page |  PDF download Page Link |
| Abstract(in Japanese) | (See Japanese page) |
| Abstract(in English) | This paper investigates the application of contrast enhancement to photographs for structure from motion (SfM), where SfM constructs a three-dimensional (3D) model of the subject from a set of multiple pictures of the subject taken from the surroundings. In the pipeline of SfM, feature points are first extracted from each photograph, then, extracted feature points are matched between all pair of photographs based on the feature values calculated at the feature points. After that, the photo shooting positions and feature points positions that satisfy the constraint conditions in 3D coordinates are calculated from matched feature points to obtain a 3D point cloud. One of the reasons that no 3D model is constructed from the set of photographs including ones with dark regions is that feature points cannot be adequately extracted from the dark areas. To this end, this paper considers applying contrast enhancement to photographs as a preprocessing process of SfM. All the investigated contrast enhancement techniques improves contrast in dark areas, but some of them insufficiently enhance the contrast in dark regions and some others over-brighten bright areas that results in loss of some of feature points in bright areas. In addition, from performance evaluation based on the number of extracted feature points per picture, the number of matched feature points, and the number of points in the 3D point cloud, it is confirmed that the suitable contrast enhance technique depends on the set of photographs. These results suggests that it is possible to select the contrast enhanced technique to be used according to the characteristics of the set of photographs. |
| Keyword(in Japanese) | (See Japanese page) |
| Keyword(in English) | contrast stretching / three-dimensional model / histogram / SLAM / digital photogrammetry |
| Paper # | SIS2021-18 |
| Date of Issue | 2021-09-30 (SIS) |
| Conference Information | |
| Committee | SIS / ITE-BCT |
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| Conference Date | 2021/10/7(2days) |
| Place (in Japanese) | (See Japanese page) |
| Place (in English) | Online |
| Topics (in Japanese) | (See Japanese page) |
| Topics (in English) | System Implementation Technology, Short Range Wireless Systems, Smart Multimedia Systems, Broadcasting Technology, etc. |
| Chair | Noriaki Suetake(Yamaguchi Univ.) / Kyoichi Saito(NHK) |
| Vice Chair | Tomoaki Kimura(Kanagawa Inst. of Tech.) / Naoto Sasaoka(Tottori Univ.) / Hidekazu Murata(Kyoto Univ.) / Hajime Saito(TV Tokyo) |
| Secretary | Tomoaki Kimura(National Inst. of Tech., Ube College) / Naoto Sasaoka(NTT) / Hidekazu Murata(NHK) / Hajime Saito(TV Asahi) |
| Assistant | Soh Yoshida(Kansai Univ.) / Yoshiaki Makabe(Kanagawa Inst. of Tech.) / Hiroshi Tsutsui(Hokkaido Univ.) / Akihiro Tanabe(NTT) / Toshimitsu Kobayashi(NBN) |
| Paper Information | |
| Registration To | Technical Committee on Smart Info-Media Systems / Technical Group on Broadcasting and Communication Technologies |
|---|---|
| Language | JPN |
| Title (in Japanese) | (See Japanese page) |
| Sub Title (in Japanese) | (See Japanese page) |
| Title (in English) | A Study on Contrast Enhancement of Images for SfM |
| Sub Title (in English) | |
| Keyword(1) | contrast stretching |
| Keyword(2) | three-dimensional model |
| Keyword(3) | histogram |
| Keyword(4) | SLAM |
| Keyword(5) | digital photogrammetry |
| 1st Author's Name | Kazuaki Takahashi |
| 1st Author's Affiliation | Tokyo Metropolitan University(Tokyo Metro. Univ.) |
| 2nd Author's Name | Masaaki Fujiyoshi |
| 2nd Author's Affiliation | Tokyo Metropolitan University(Tokyo Metro. Univ.) |
| Date | 2021-10-08 |
| Paper # | SIS2021-18 |
| Volume (vol) | vol.121 |
| Number (no) | SIS-190 |
| Page | pp.pp.42-47(SIS), |
| #Pages | 6 |
| Date of Issue | 2021-09-30 (SIS) |