Ken Sakurada

Dr. Ken Sakurada


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
15 October 2019
Verified
Conference Paper
Open access
PDF file
SSShinya Sumikura
Shinya Sumikura
MSMikiya Shibuya
Mikiya Shibuya
KSKen Sakurada
Ken Sakurada
6 3) 1 6 8 1 1) 8 6 (0) 1 6 Figure 1: One of the noteworthy features of OpenVSLAM: 3D scene mapping with various types of camera models.

17 November 2020
Verified
Book Chapter
Closed access
PDF file
MSMikiya Shibuya
Mikiya Shibuya
SSShinya Sumikura
Shinya Sumikura
KSKen Sakurada
Ken Sakurada

27 August 2022 in Remote Sensing
Verified
Journal Article
Open access
PDF file
KDKento Doi
Kento Doi
RHRyuhei Hamaguchi
Ryuhei Hamaguchi
YIYusuke Iwasawa
Yusuke Iwasawa
MOMasaki Onishi
Masaki Onishi
YMYutaka Matsuo
Yutaka Matsuo
KSKen Sakurada
Ken Sakurada
We developed a robust object-level change detection method that could capture distinct scene changes in an image pair with viewpoint differences. To achieve this, we designed a network that could detect object-level changes in an image pair. In contrast to previous studies, we considered the change detection task as a graph matching problem for two object graphs that were extracted from each image. By virtue of this, the proposed network more robustly detected object-level changes with viewpoint differences than existing pixel-level approaches. In addition, the network did not require pixel-level change annotations, which have been required in previous studies. Specifically, the proposed network extracted the objects in each image using an object detection module and then constructed correspondences between the objects using an object matching module. Finally, the network detected objects that appeared or disappeared in a scene using the correspondences that were obtained between the objects. To verify the effectiveness of the proposed network, we created a synthetic dataset of images that contained object-level changes. In experiments on the created dataset, the proposed method improved the F1 score of conventional methods by more than 40%. Our synthetic dataset will be available publicly online.

1 April 2017 in Computer Vision and Image Understanding
Verified
Journal Article
Closed access
KSKen Sakurada
Ken Sakurada
DTDaiki Tetsuka
Daiki Tetsuka
TOTakayuki Okatani
Takayuki Okatani

19 April 2023
Verified
Conference Paper
Open access
SKSeita Kayukawa
Seita Kayukawa
KHKeita Higuchi
Keita Higuchi
SMShigeo Morishima
Shigeo Morishima
KSKen Sakurada
Ken Sakurada
We present an interactive route viewer system, 3DMovieMap, which generates and shows navigation movies walking through multi-level buildings, such as a science museum, airport, and university building. Movie map systems can provide users with visual cues by synthesizing navigation movies based on their inputs of routes. However, existing systems are limited to flat areas such as city areas. We aim to extend Movie Map to generate navigation movies for multi-level buildings. The 3DMovieMap system generates a movie map from an equirectangular movie via a visual Simultaneous Localization and Mapping technology. Users select waypoints on the floor maps. 3DMovieMap calculates the shortest path that visits these points and generates a navigation movie along the route. We created four movie maps of buildings and asked two participants to use our system and provide feedback for further improvements. We will be releasing an open dataset of equirectangular movies captured in a science museum.

9 March 2020 in arXiv
Verified
Preprint
Open access
PDF file
WWWeimin Wang
Weimin Wang
SNShohei Nobuhara
Shohei Nobuhara
RNRyosuke Nakamura
Ryosuke Nakamura
KSKen Sakurada
Ken Sakurada
This paper presents a novel semantic-based online extrinsic calibration approach, SOIC (so, I see), for Light Detection and Ranging (LiDAR) and camera sensors. Previous online calibration methods usually need prior knowledge of rough initial values for optimization. The proposed approach removes this limitation by converting the initialization problem to a Perspective-n-Point (PnP) problem with the introduction of semantic centroids (SCs). The closed-form solution of this PnP problem has been well researched and can be found with existing PnP methods. Since the semantic centroid of the point cloud usually does not accurately match with that of the corresponding image, the accuracy of parameters are not improved even after a nonlinear refinement process. Thus, a cost function based on the constraint of the correspondence between semantic elements from both point cloud and image data is formulated. Subsequently, optimal extrinsic parameters are estimated by minimizing the cost function. We evaluate the proposed method either with GT or predicted semantics on KITTI dataset. Experimental results and comparisons with the baseline method verify the feasibility of the initialization strategy and the accuracy of the calibration approach. In addition, we release the source code at https://github.com/--/SOIC.