References of "Verly, Jacques"
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See detailProbabilistic Framework for the Characterization of Surfaces and Edges in Range Images, with Application to Edge Detection
Lejeune, Antoine ULg; Verly, Jacques ULg; Van Droogenbroeck, Marc ULg

in IEEE Transactions on Pattern Analysis & Machine Intelligence (in press)

We develop a powerful probabilistic framework for the local characterization of surfaces and edges in range images, which is useful in many applications of computer vision, such as filtering, edge ... [more ▼]

We develop a powerful probabilistic framework for the local characterization of surfaces and edges in range images, which is useful in many applications of computer vision, such as filtering, edge detection, feature extraction, and classification. We use the geometrical nature of the data to derive an analytic expression for the joint probability density function (pdf) for the random variables used to model the ranges of a set of pixels in a local neighborhood of an image. We decompose this joint pdf by considering independently the cases where two real world points corresponding to two neighboring pixels are locally on the same real world surface or not. In particular, we show that this joint pdf is linked to the Voigt pdf and not to the Gaussian pdf as it is assumed in some applications. We apply our framework to edge detection and develop a locally adaptive algorithm that is based on a probabilistic decision rule. We show in an objective evaluation that this new edge detector performs better than prior art edge detectors. This proves the benefits of the probabilistic characterization of the local neighborhood as a tool to improve applications that involve range images. [less ▲]

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See detailA Novel Accelerometer-Based Method for Stride Length Estimation
Boutaayamou, Mohamed ULg; Schwartz, Cédric ULg; Denoël, Vincent ULg et al

Poster (2017, July 14)

We demonstrate the feasibility of accurately and precisely estimating the left/right average stride length from measured heel/toe accelerations in the gait of healthy, old adults. Our approach relies on ... [more ▼]

We demonstrate the feasibility of accurately and precisely estimating the left/right average stride length from measured heel/toe accelerations in the gait of healthy, old adults. Our approach relies on (1) a novel method that uses only accelerometer data without the need of additional data from, e.g., gyroscopes and/or magnetometers, and on (2) the validation of the results using reference 3D optoelectronic system data. [less ▲]

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See detailCubesats activities at the University of Liège
Werner, Xavier ULg; Broun, Valery ULg; De Dijcker, Sébastien ULg et al

Conference given outside the academic context (2017)

Detailed reference viewed: 18 (3 ULg)
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See detailOUFTI-2 educational CubeSat project of University of Liège, Belgium
Guillaume, Thibaut; Rikir, Adrien; De Dijcker, Sébastien ULg et al

Scientific conference (2017, May 03)

Detailed reference viewed: 177 (72 ULg)
See detailAmbulatory System for Gait Analysis
Boutaayamou, Mohamed ULg; Bruls, Olivier ULg; Croisier, Jean-Louis ULg et al

Conference (2017, April 29)

We describe the principle and use of a wireless, 3-axis accelerometer-based ambulatory system that records acceleration signals and automatically analyses them to characterize normal and pathological gait ... [more ▼]

We describe the principle and use of a wireless, 3-axis accelerometer-based ambulatory system that records acceleration signals and automatically analyses them to characterize normal and pathological gait. The associated algorithm is versatile enough to detect, on a stride-by-stride basis, refined gait parameters that quantify subtle gait disturbances in, e.g., in Parkinson’s disease in a rater-independent way. The experimental results show the potential of the developed accelerometer-based technique to be used in neurology (e.g., characterization of Parkinsonian gait: slowness, shuffling, short steps, freezing of gait, asymmetries in gait), rehabilitation, geriatrics (ex. monitoring activity parameters in the elderly), orthopedics and sport. [less ▲]

Detailed reference viewed: 20 (3 ULg)
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See detailIMPACT OF IMAGE BRIGHTNESS REDUCTION ON PERCEIVED QUALITY OF 3D EXPERIENCE FOR 3D CINEMA SPECTATORS
Loock, Severin; Grogna, David ULg; Jaspar, Mathieu ULg et al

in International Conference on 3D Imaging (IC3D) (2017)

3D movies are calibrated to meet a certain screen bright- ness standard. Therefore, what would be the consequences on the quality of the 3D experience for spectators watching a 3D movie when movie ... [more ▼]

3D movies are calibrated to meet a certain screen bright- ness standard. Therefore, what would be the consequences on the quality of the 3D experience for spectators watching a 3D movie when movie theaters do not respect this standard? First, we attempted to better understand which factors were important for a spectator by conducting an experiment where participants watched a 3D movie and filled out an exploratory questionnaire. Then, we aimed to investigate the link between image brightness loss and the quality of the 3D experience as perceived by the spectator. First results show no perceived difference in the quality of the 3D experience between a nor- mal brightness and a brightness decreased by 10% for four factors, i.e. (1) the appreciation of the movie, (2) the con- tent of the movie, (3) the 3D quality of the movie, and (4) the quality of the 3D experience in general. [less ▲]

Detailed reference viewed: 14 (1 ULg)
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See detailObjective assessment of visual pursuit in patients with disorders of consciousness: an exploratory study.
Wannez, Sarah ULg; Hoyoux, Thomas; Langohr, Thomas et al

in Journal of Neurology (2017)

Detailed reference viewed: 21 (8 ULg)
See detailAlgorithm for Temporal Gait Analysis Using Wireless Foot-Mounted Accelerometers
Boutaayamou, Mohamed ULg; Denoël, Vincent ULg; Bruls, Olivier ULg et al

Book published by Springer (2017)

We present a new signal processing algorithm that extracts five gait events: heel strike, toe strike, heel-off, toe-off, and heel clearance from only two accelerometers attached on the heels of the ... [more ▼]

We present a new signal processing algorithm that extracts five gait events: heel strike, toe strike, heel-off, toe-off, and heel clearance from only two accelerometers attached on the heels of the subjects usual shoes. This algorithm first uses a continuous wavelet-based segmentation that parses the signal of consecutive strides into motionless periods defining relevant local acceleration signals. Then, the algorithm uses versatile techniques to accurately extract the five gait events from these local acceleration signals. We validated, on a stride-by-stride basis, the extraction of these gait events by comparing the results with reference data provided by a kinematic 3D analysis system and a video camera. The accuracy and precision achieved by the extraction algorithm for healthy subjects, the reduced number of accelerometer units required, and the validation results obtained, encourage us to further study this system in pathological conditions. [less ▲]

Detailed reference viewed: 74 (27 ULg)
See detail3D and stereoscopy
Verly, Jacques ULg; Grogna, David ULg; Lejeune, Antoine ULg

Conference given outside the academic context (2016)

Detailed reference viewed: 25 (2 ULg)
See detailOUFTI-1 : comment les étudiants belges ont envoyé un satellite en orbite
Verly, Jacques ULg; Kerschen, Gaëtan ULg; Werner, Xavier ULg et al

Conference given outside the academic context (2016)

Detailed reference viewed: 48 (6 ULg)
See detail3D Stereo MEDIA 2016, an international event at the service of companies
Verly, Jacques ULg

Scientific conference (2016, October 05)

Detailed reference viewed: 33 (5 ULg)
See detailGoal of 3D Express and quick panorama of 3D
Verly, Jacques ULg

Scientific conference (2016, October 05)

Detailed reference viewed: 23 (1 ULg)
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See detailObjective drowsiness monitoring to assess fitness for duty
François, Clémentine ULg; Hoyoux, Thomas ULg; Langohr, Thomas ULg et al

Poster (2016, September 16)

Detailed reference viewed: 24 (7 ULg)