Search results for "Graphics"

Digital communication environments in the workplace

2019

Digital communication environments consist of various kinds of communication technologies and collaboration platforms. These enable employees to communicate through text, audio, video, and graphics, often in an open and networked way. Complementing the popular stand-alone communication tools regularly used in workplaces, such as email and instant messaging, digital communication environments enable the sharing, editing, and storing of information publicly within the organization and sometimes externally among its stakeholders. This chapter reviews and analyzes digital communication environments as well as their affordances and constraints for communication and social interaction in the work…

Effect of Footstep Vibrations and Proprioceptive Vibrations Used with an Innovative Navigation Method

2017

This study proposes to investigate the effect of adding vibration feedback to a navigation task in virtual environment. Previous study used footstep vibrations and proprioceptive vibrations in order to decrease the cyber-sickness and increase the sense of presence. In this study, we experiment the same vibration modalities but with a new navigation method. The results show that proprioceptive vibrations do not impact the sense of presence neither the cyber-sickness while footstep vibrations increase sense of presence and decrease in a certain way cyber-sickness. Burgundy region through the JCE funding project

A New Myohaptic Device to Assess Wrist Function in the Lab and in the Clinic – The Wristalyzer

2008

Wristalyzer is a portable robotic device combining haptic technology with electromyographic assessment. It allows to assess wrist motion in physiological and pathological conditions by applying loads and mechanical oscillations, taking into account the ergonomy and the angular positioning of the joints. The wristalyzer works in a free or loaded mode for assessment of metrics of motion and tremor, analyzes the behavior of the wrist joints and the associated muscle activities during delivery of mechanical oscillations, estimates the maximal voluntary contraction, assesses automatically the impedance of the wrist for assessment of rigidity or spasticity. Position, torques and electromyographic…

GPU-Based Occlusion Minimisation for Optimal Placement of Multiple 3D Cameras

2020

This paper presents a fast GPU-based solution to the 3D occlusion detection problem and the 3D camera placement optimisation problem. Occlusion detection is incorporated into the optimisation problem to return near-optimal positions for 3D cameras in environments containing occluding objects, which maximises the volume that is visible to the cameras. In addition, the authors’ previous work on 3D sensor placement optimisation is extended to include a model for a pyramid-shaped viewing frustum and to take the camera’s pose into account when computing the optimal position.

Corrigendum to “Intelligent agents for feature modelling in computer aided design” [J. Comput. Des. Eng. (2018) 19–40]

2018

Direct 3D Information Determination in an Uncalibrated Stereovision System by Using Evolutionary Algorithms

2011

This paper proposes a 3D panoramic shape reconstruction method based on an uncalibrated stereovision system (USS) composed of five cameras circularly located around the object to be analysed. First, some interesting points are detected from markers placed on the object such that they are visible by two successive cameras of the USS. These points are then matched on both images acquired by a couple of successive cameras. This process is repeated for all the couples of cameras. Second, by using an evolutionary algorithm, the depth values of the different interesting points are calculated. A comparison with a traditional method based on calibrated cameras validates the accuracy of 3D informati…

Seam-Based Edge Blending for Multi-Projection Systems

2016

Perceptual seamlessness of large-scale tiled displays is still a challenge. One way to avoid Bezel effects from contiguous displays is to blend superimposed parts of the image over the edges. This work proposes a new approach for edge blending. It is based on intensity edge blending adapted on the seam description of the image content. The main advantage of this method is to reduce visual artifacts thanks to context adaptation and smooth transitions. We evaluate the quality of the method with a perceptual experiment where it is compared with state-of-the-art methods. The new method shows most improvement in low frequency areas compared to the other techniques. This method can be inserted in…

Efficient Skin Detection under Severe Illumination Changes and Shadows

2011

International audience; This paper presents an efficient method for human skin color detection with a mobile platform. The proposed method is based on modeling the skin distribution in a log-chromaticity color space which shows good invariance properties to changing illumination. The method is easy to implement and can cope with the requirements of real-world tasks such as illumination variations, shadows and moving camera. Extensive experiments show the good performance of the proposed method and its robustness against abrupt changes of illumination and shadows.

Hand Detection and Tracking Using the Skeleton of the Blob for Medical Rehabilitation Applications

2012

This article presents an image processing application for hand detection and tracking using the 4-connected skeleton of the segmentation mask. The system has been designed to be used with techniques of virtual reality to develop an interactive application for phantom limb pain reduction in therapeutic treatments. One of the major contributions is the design of a fast and accurate skeleton extractor, that has proven to be faster than those available in the literature. The skeleton allows the system to precisely detect the position of all the interest points of the hand (namely the fingers and the hand center). The system, composed of both the hand detector and tracker, and the virtual realit…

Calibration of a three-dimensional reconstruction system using a structured light source

2002

We present a method for calibrating a range finder system composed of a camera and a structured light source. The system is used to reconstruct the three-dimensional (3-D) surface of an object. This is achieved by projecting a pattern, represented by a set of regularly spaced spots, on the surface of the object using the structured light source. An image of the illuminated object is next taken and by analyzing the distortion of the projected pattern, the 3-D surface of the object can be reconstructed. This reconstruction operation can be envisaged only if the system is calibrated. Instead of using a classical calibration method, which is based on the determination of the matrices that chara…