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Image-based visual servo using coordinates of feature points has been well discussed and used in many applications. However, these methods rely on the perfect matching of feature points, which is often difficult in an actual situation. Recently, visual servoing methods based on region informations such as mutual information and an image transformation matrix are proposed. While these methods can achieve...
We present a stereo visual odometry algorithm with trajectorical information accumulated over time and consistency among multiple trajectories of different motions. The objective function considers transfer error of all previously observed points to reduce drifting, and can be efficiently approximated and optimized within a computational bound. Different from traditional residual-based consistency...
We present Alone Together, a collaborative virtual ball playing environment augmented with three sets of Microsoft Kinect. The play environment fulfills a 'sport over the distance' them via the attempt to mimic the real world ballpassing exercise (or rehabilitation sessions) except that the players can be miles away from each other, and they interact without a physical ball. Moreover, our system allows...
This paper makes use of recent advances in group tracking and behavior recognition to process large amounts of video surveillance data from an underground railway station and perform a statistical analysis. The most important advantages of our approach are the robustness to process long videos and the capacity to recognize several and different events at once. This analysis automatically brings forward...
Visual mapping is a required capability for practical autonomous mobile robots where there exists a growing industry with applications ranging from the service to industrial sectors. Prior to map building, Visual Odometry(VO) is an essential step required in the process of pose graph construction. In this work, we first propose to tackle the pose estimation problem by using both photometric and geometric...
To assess web-enabled products and coverage induction properties of the overall network, this paper provides a wireless sensor networks node deployment effect detection method based on the target trajectory. According to the wireless sensor networks node sensing performance in monitoring area, this method structures the distribution diagram of induction ability forces, marks the weak induction area,...
The bag-of-visual-words model has been widely utilized for content based image and video retrieval due to its scalability. In this paper, we extend this model for human action video retrieval. We adopt dense trajectory features which are able to achieve the state-of-the-art performance on action recognition, while most of the existing video retrieval methods utilize descriptors of local interest points...
Multichannel biotechnical system is designed to study human emotional reactions to external stimuli by recording and analyzing speech samples test or electroencephalogram signals. The system allows you to create complex stimuli for the perception that the subject uses a visual, acoustic or olfactory system. For registration of biological signals earmarked voice recording and electroencephalogram (EEG)...
In this study, an attempt to produce vowel sounds by means of an eye-gaze interface system was made. A vocal tract mapping interface which can configure the vocal tract shape and produce vowel sounds was combined with an eye-gaze interface system using socket connection. Taking advantage of one-click operation for configuring the vocal tract shape, a user can produce continuous change in the vocal...
Perceptual mechanisms humans use in motion planning and guidance are responsible for their agile and versatile capabilities. Their understandings would help advance both autonomous control and improve human-machine interfaces. This paper extends prior work by collecting human trajectory and gaze data while performing simulated first-person motion guidance tasks. This data is considered under the hypothesis...
Brain-machine interfaces (BMIs) have demonstrated how they can be used for reaching tasks with both invasive and non-invasive signal recording methods. Despite the constant improvements in this field, there still exist diverse factors to overcome before achieving a natural control. In particular, the high variability of the brain signals often leads to the incorrect decoding of the subject intentions,...
In this paper we implemented a system of fisheye vision (a 360° × 180° visual field) for georeferenced tracking of feature points associated with moving objects in urban scenes. To develop this system: 1. We calibrate the intrinsic parameters of a fisheye camera based on the stereographic model. 2. We propose a geometric model of image formation and adjust the position and orientation parameters using...
Visual information is heavily used in robotics, in particular for SLAM applications. Visual SLAM algorithms depend on robust feature extraction and reliable state estimation. Quality of the visual information highly depends on how that information is captured. The nature of snake robots' locomotion presents considerable challenges on the quality of images captured by an onboard mobile camera. Although...
We attack the problem of persistently tracking cooperative people such as children, the elderly or patients by combining passive tracking and active tracking techniques. Passive tracking uses visual signals from surveillance cameras, but vision based people tracking becomes a hard problem in challenging scenarios such as long-term/heavy occlusion, people changing their movement patterns during occlusion,...
This paper presents a trifocal tensor based approach for the visual trajectory tracking task of a nonholonomic mobile robot, which is equipped with a roughly installed monocular camera. A set of pre-recorded images are used to express the desired trajectory, and the robot is regulated to track the desired trajectory using visual feedback. Trifocal tensor is exploited to obtain the orientation and...
We develop and evaluate methods based on a novel data compression strategy for visual SLAM that uses traveled trajectory analysis. Beyond compressing scene structure based purely on geometry, we aim at developing compact map representations that are useful for re-exploration while preserving scene structure. Our work is evaluated on data collected from a visual sensor and exploits the information...
How efficiently decoding affective information when computational resources and sensor systems are limited? This paper presents a framework for analysis of affective behavior starting with a reduced amount of visual information related to human upper-body movements. The main goal is to individuate a minimal representation of emotional displays based on non-verbal gesture features. The GEMEP (Geneva...
In this paper, we present an appearance-based visual SLAM approach that focuses on detecting loop closures across seasons. Given two image sequences, our method first extracts one descriptor per image for both sequences using a deep convolutional neural network. Then, we compute a similarity matrix by comparing each image of a query sequence with a database. Finally, based on the similarity matrix,...
Human-action recognition through local spatio-temporal features have been widely applied because of their simplicity and its reasonable computational complexity. The most common method to represent such features is the well-known Bag-of-Words approach, which turns a Multiple-Instance Learning problem into a supervised learning one, which can be addressed by a standard classifier. In this paper, a...
We propose a video graph based human action recognition framework. Given an input video sequence, we extract spatio-temporal local features and construct a video graph to incorporate appearance and motion constraints to reflect the spatio-temporal dependencies among features. them. In particular, we extend a popular dbscan density-based clustering algorithm to form an intuitive video graph. During...
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