Research Topics

The Pattern Recognition Lab main research topics are

• perception systems
• 3D computer vision
• microvision
• other past topics

1. Microvision

This research topic deals with the optimization of complex vision systems.

Vision System configuration  The developed configurator is an expert module that improves the ease of use of versatile industrial vision systems. It assists the operator by automatically providing optimal parameter settings for a new configuration of the working environment. It relieves him from the tedious task of system setup. In operation, the configurator learns from a small number of examples and derives a system setting with optimal expected performance. The developed assistant is currently operational in the case of the visual inspection of IC markings. The benefit is an improved and faster system setup. Other ongoing activities concern: burr measurement and analysis wood topographic analysis

Badly configured vision system

2. 3D Computer Vision

Modern range cameras provide means to measure 3D surfaces easily and automatically, but also set the need for new 3D data interpretation methods.

3D Scene Analysis 3D vision surpasses the limitations of classical video vision in applications like control. surveillance and security. This ends difficulties with shadows and other foreign illumination effects.

Badly configured vision system

From real to virtual objects Modeling 3D objects requires the measurement of the object under different views and the subsequent assembly of the views. 1) The measurement is performed by a 3D-scanner that acquires range images 2) Several range images corresponding to different views are needed in order to obtain measurements that cover the complete object 3) During assembly, the various views must be brought together. It requires an exact positioning of the geometry and the merging of the data meshes derived from each range image. The final model describes the full geometry and the color of the object. Applications of 3D modeling are numerous: industrial design, reverse engineering, simulation, 3D photography, building and updating virtual environments, object recognition, ... Other ongoing activities concern: fast 3D matching methods micro-particle modeling

Reverse Engineering model of a watch frame

3. Perception Systems

This research topic aims at improving scene analysis tasks by an efficient design of the early stage of the vision process. Several modes and cues of perception are considered.
Also the vision process is composed of a preattentive stage followed by another stage of attentive vision. The interest focuses on visual attention and other related subjects.

Visual attention An ongoing activity considers the task of extended visual attention by investigating attention models, which consider scene depth as a perception mode that complements visual perception. The study is oriented towards a new model of multimodal perception as well as its use for solving segmentation and scene understanding tasks. Other ongoing activities concern: hardware for real-time visual attention computation multicue visual attention human vs computer visual attention

Spot of visual attention obtained by a multimodal computer model

4. Other Past Topics

Character recognition Character recognition is best performed on-line when processing is directly part of the sensing device. Several recognition methods are available as candidate for operation in a miniaturized device. Following figure illustrates the recognition by a feed-forward neural network.

On-line acquired character

Robot vision Because the environment of a robot is often unpredictable and changing, there is a strong need to fit out robots with sensing capabilities like vision. We investigate the integration of vision in the frame of the behavioural architecture for the design of mobile robots.

Mobile robot navigation

Spray quality inspection Judging the quality of spray jets is performed routinely by human visual inspection. In this project, we investigated means to perform the task automatically by image analysis. We demonstrated                            its feasibility and designed a prototype system. In this inspection task, image analysis offers the advantage of an objective, non-destructive and flexible inspection method.

Spray jet shape analysis