Visual-auditory substitution device for indoor navigation based on fast visual marker detection

Capturing and Indexing Rehearsals: The Design and Usage of a Digital Archive of Performing Arts

International audience; Preserving the cultural heritage of the performing arts raises difficult and sensitive issues, as each performance is unique by nature and the juxtaposition between the performers and the audience cannot be easily recorded. In this paper, we report on an experimental research project to preserve another aspect of the performing arts—the history of their rehearsals. We have specifically designed non-intrusive video recording and on-site documentation techniques to make this process transparent to the creative crew, and have developed a complete workflow to publish the recorded video data and their corresponding meta-data online as Open Data using state-of-the-art audi…

Thermal camera calibration with cooled down chessboard

International audience; Calibration of a camera have various applications in computer vision. This process is particularly challenging with a thermal camera instead of a standard color one. A calibration target with two layers of different thermal emissivity is commonly used but reflects appear and degrade the corner extraction of the chessboard. While traditional and commonly used methods heat the target chessboard, we cool it down that inverts the distribution of emission of the two layers. The reflects on the reflective layer enhance the contrast instead of decreasing it. Experiments on various configurations and orientations demonstrate the superiority of the proposed method.

Time Unification on Local Binary Patterns Three Orthogonal Planes for Facial Expression Recognition

International audience; Machine learning has known a tremendous growth within the last years, and lately, thanks to that, some computer vision algorithms started to access what is difficult or even impossible to perceive by the human eye. While deep learning based computer vision algorithms have made themselves more and more present in the recent years, more classical feature extraction methods, such as the ones based on Local Binary Patterns (LBP), still present a non negligible interest, especially when dealing with small datasets. Furthermore, this operator has proven to be quite useful for facial emotions and human gestures recognition in general. Micro-Expression (ME) classification is…

MOISST: Multimodal Optimization of Implicit Scene for SpatioTemporal calibration

With the recent advances in autonomous driving and the decreasing cost of LiDARs, the use of multimodal sensor systems is on the rise. However, in order to make use of the information provided by a variety of complimentary sensors, it is necessary to accurately calibrate them. We take advantage of recent advances in computer graphics and implicit volumetric scene representation to tackle the problem of multi-sensor spatial and temporal calibration. Thanks to a new formulation of the Neural Radiance Field (NeRF) optimization, we are able to jointly optimize calibration parameters along with scene representation based on radiometric and geometric measurements. Our method enables accurate and …

3D Point Cloud Descriptor for Posture Recognition

International audience

Tracking Hands in Interaction with Objects: A Review

Markerless vision-based 3D hand motion tracking is a key and popular component for interaction studies in many domains such as virtual reality and natural human-computer interfaces. While this research field has been well studied in the last decades, most approaches have considered the human hand in isolation and not in action or in interaction with the environment or the other articulated human body parts. Employing contextual information about the surrounding environment (e.g. the shape, the texture, and the posture of the object in the hand) can remarkably constrain the tracking problem. The goal of this survey is to develop an up-to-date taxonomy of existing vision-based hand tracking m…