Vu Hai's homepage

About me | Research Topics | Publications |  Professional Activities  | Home

Reasearch Topics: Vision-based system supporting visually impaired people

Video Capsule Endoscopy Analysis
Computer Vision in Agricultural Engineering and Biodiversity
Human Computer Interaction
Human in a Surveillance Camera Network

Obstacle Detection and Distance estimation using monocular camera in nagivation service for visually impaired people
In this paper, we propose a method for obstacle detection and distance estimation using monocular camera mounted on a mobile robot. The
proposed system aims to support visually impaired people navigating in indoor environ-ment. The obstacles include static and dynamic objects on that encumber human mobility. For static objects, supporting information such as type of object, positions, and corresponding images in relevant
scenes are stored in database (DB). To detect them, the images captured during robot’s movements are compared with the corresponding images through a localization algorithm proposed in [1]. Then the existing objects in DB will be identified and distances from them to current robot’s position is
estimated. For dynamic objects, such as movements of people in scenes, we use HOG-SVM algorithm [2]. To estimate distance from camera to detected
obstacles, we utilize a disparity map which is built from consecutive frames. The experiments are evaluated in the hall of building floor of 60 meters
under different lighting conditions. The results confirm that the proposed method could exactly detect and esti-mate both static and dynamic objects.
This shows the feasibility to help visually impaired people avoiding obstacles in navigation.
  • [1]  NGUYEN Quoc Hung, TRAN Thi Thanh Hai, VU Hai, Hoang Van Nam, NGUYEN Quang Hoan, "Nghiên cứu phương pháp phát hiện và ước lượng khoảng cách vật cản ứng dụng cho bài toán robot dẫn đường trợ giúp người khiếm thị", Tạp chí Khoa học công nghệ Thông tin và Truyền thông, Học viện Công nghệ Bưu chính Viễn thông, Vol.1, 2016 (Vietnamese)

Indoor assistance for visually impaired people using a RGB-D camera
In this paper a navigational aid for visually impaired people is presented. The system uses a RGB-D camera to perceive the environment and implements self-localization, obstacle detection and obstacle classification. The novelty of this work is threefold. First, self-localization is performed by means of a novel camera tracking approach that uses both depth and color information. Second, to provide the user with semantic information, obstacles are classified as walls, doors, steps and a residual class that covers isolated objects and bumpy parts on the floor. Third, in order to guarantee real time performance, the system is accelerated by offloading parallel operations to the GPU. Experiments demonstrate that the whole system is running
at 9 Hz.
  • [1] Thi Son Nguyen, Thanh Hai Tran, Hai Vu,"Accurate object localization using RFID and Microsoft Kinect Sensor", in the Proceeding of The 1st International Workshop on Pattern Recognition for Multimedia Content Analysis (PR4MCA 2016), in conjunction with the 8th International Conference on Knowledge and System Engineering, Hanoi, Vietnam, 2016
  • [2]  Michiel Vlaminck, Hiep Quang Luong, Hoang Van Nam, Hai Vu, Peter Veelaert, Wilfried Philips, "Indoor assistance for visually impaired people using a RGB-D camera", in Proceeding of the IEEE Southwest Symposium on Image Analysis and Interpretation, 2016, Santa Fe, New Mexico, USA

Geometry-based 3D Object Fitting and Localization in Grasping Aid for Visually Impaired People
This paper presents a geometry-based method for 3D object fitting and localization in the context of building a grasping aid service for visually impaired people using information from Kinect sensor. Given two constraints of this working application, (1) the interested object is on a table and (2) the geometrical form of the object is known in advance based on the query of the user, the proposed system consists of three steps: table plane detection, object detection, and object fitting and localization. Our work has three contributions. First, we propose to use organized point cloud representation instead of just point cloud in order to speedup the computational time and improve the accuracy of table plane detection. Second, we employ MLESAC (Maximum LikElihood SAmple Consensus) that can give better results for object fitting. Third, we introduce a new method for evaluating object localization task and make a quantitative evaluation of object localization on our captured dataset.
  • [1] LE Van Hung, VLAMINCK Michiel , VU Hai, NGUYEN Thi Thuy, LE Thi Lan, TRAN Thi Thanh Hai, LUONG Hiep Quang, VEELAERT Peter, WILFRIED Philips, "REAL-TIME TABLE PLANE DETECTION USING ACCELEROMETER INFORMATION AND ORGANIZED POINT CLOUD DATA FROM KINECT SENSOR", Journal of Computer Science and Cybernetics, Vietnam Academy of Science & Technology - No. 3, 2016
  • [2]  Hung Le Van, Thi Lan Le, Hai Vu, Thi Thuy Nguyen, Thanh Hai Tran,  Tran-Chung Dao, Hong-Quan Nguyen, "Geometry-based 3D Object Fitting and Localization in Grasping Aid for Visually Impaired People", to appear in the Proceeding of the IEEE International Conference on Communications and Electronics (ICCE), 2016, Ha Long, Vietnam
  • [3] LE Van Hung, Hai Vu, Thi-Thuy Nguyen, LE Thi Lan, TRAN Thi Thanh Hai, VLAMINCK Michiel , WILFRIED Philips, VEELAERT Peter , "Query-based 3D Object Finding Using Geometrical Constraints on Depth Images for Assisting the Visually Impaired", in the Proceeding of The 1st International Workshop on Pattern Recognition for Multimedia Content Analysis (PR4MCA 2015), in conjunction with the 7th International Conference on Knowledge and System Engineering,  HoChiMinh city, Vietnam, 2015

Mapping Services in Indoor Enviroments
This paper describes a visual-based system that autonomously operators for both map building and localization tasks. The proposed system is to assist mapping services in small or mid-scale environments such as inside a building or campus of school where conventional positioning data such as GPS, WIFI signals are often not available. Toward this end, the proposed approaches utilize only visual data. We design an image acquisition system for data collections. On one hand, a robust visual odometry method is utilized to create routes in the environment. On the other hand, the proposed approaches utilize FAB-MAP (Fast Appearance Based Mapping) algorithm that is
maybe the most successful for recognizing places in large scenarios. The building route and learning visited places are offline process in order to represent a map of environment. Through
a matching image-to-map procedure, the captured images at current view are continuously positioned on the constructed map. This is an online process. The proposed system is evaluated in a corridor environment of a large building. The experimental results show that the constructed route coincides with ground truth, and matching image-to-map is high confidence. The proposed
approaches are feasible to support visually impaired people navigating in the indoor environments.
  • [1]  NGUYEN Quoc Hung, Hai Vu, TRAN Thi Thanh Hai, NGUYEN Quang Hoan, "Mapping Services in Indoor Enviroments based on Image Sequences", in the Proceeding of the 5th International Conference on Communications and Electronics (ICCE), Danang, Vietnam, July 2014
  • [2] NGUYEN Quoc Hung, Vu Hai, TRAN Thi Thanh Hai, NGUYEN Quang Hoan, "Improving localization precision of visual SLAM using Kalman filter", in the Proceeding of Fundamental and Applied IT Research - FAIR  2014, Thai Nguyen

A Visual SLAM system on mobile robot supporting visually impaired people
This paper describes a Visual SLAM system developed on a mobile robot in order to support localization services to visually impaired people. The proposed system aims to provide services in small or mid-scale environments such as inside a building or campus of school where conventional positioning data such as GPS,WIFI signals are often not available. Toward this end, we adapt
and improve existing vision-based techniques in order to handle issues in the indoor environments. We firstly design an image acquisition system to collect visual data. On one hand, a robust visual odometry method is adjusted to precisely create the routes in the environment. On the other hand, we utilize the Fast-Appearance BasedMapping algorithmthat is may be the most successful for matching places in large scenarios. In order to better estimate robot’s location, we utilize a Kalman Filter that combines the matching results of current observation and the estimation of robot states based on its kinematic model. The experimental results confirmed that the proposed system is feasible to navigate the visually impaired people in the indoor environments