
	Department of Computer Science and Engineering

Projects for NSERC USRA 2008

Please check back this page regularly as more projects will be added.

Professor Robert Allison

Projects in Virtual Reality

We are looking at several studies related to virtual reality and aerospace simulations including the effects of time delay in virtual environments and navigation through a virtual environment. The project would involve the development of flexible virtual environments for experimentation and the design and analysis of experiments.

Projects related to depth perception

As part of a ongoing research program we opportunities for work on research involving the depth perception and three-dimensional displays. Several different projects are ongoing ranging from studying human stereoscopic perception to the use of blur as a depth cue in computer displays.

Projects related to use of eye movements in computer displays

(Description to be posted)

Professor James Elder

Three-Dimensional Context from Linear Perspective for Video Surveillance Systems

To provide visual surveillance over a large environment, many surveillance cameras are typically deployed at widely dispersed locations. Making sense of activities within the monitored space requires security personnel to map multiple events observed on two-dimensional security monitors to the three-dimensional scene under surveillance. The cognitive load entailed rises quickly as the number of cameras, complexity of the scene and amount of traffic increases.

This problem can be addressed by automatically pre-mapping two-dimensional surveillance video data into three-dimensional coordinates. Rendering the data directly in three dimensions can potentially lighten the cognitive load of security personnel and make human activities more immediately interpretable.

Mapping surveillance video to three-dimensional coordinates requires construction of a virtual model of the three-dimensional scene. Such a model could be obtained by survey (e.g., using LIDAR), but the cost and time required for each site would severely limit deployment. Wide-baseline uncalibrated stereo methods are developing and have potential utility, but require careful sensor placement, and the difficulty of the correspondence problem limits reliability.

This project will investigate a monocular method for inferring three-dimensional context for video surveillance. The method will make use of the fact that most urban scenes obey the so-called “Manhattan-world” assumption, viz., a large proportion of the major surfaces in the scene are rectangles aligned with a three-dimensional Cartesian grid (Coughlan & Yuille, 2003). This regularity provides strong linear perspective cues that can potentially be used to automatically infer three-dimensional models of the major surfaces in the scene (up to a scale factor). These models can then be used to construct a virtual environment in which to render models of human activities in the scene.

Although the Manhattan world assumption provides powerful constraints, there are many technical challenges that must be overcome before a working prototype can be demonstrated. The prototype requires six stages of processing: 1)The major lines in each video frame are detected. 2) These lines are grouped into quadrilaterals projecting from the major surface rectangles of the scene. 3) The geometry of linear perspective and the Manhattan world constraint are exploited to estimate the three-dimensional attitude of the rectangles from which these quadrilaterals project. 4) Trihedral junctions are used to infer three-dimensional surface contact and ordinal depth relationships between these surfaces. 5) The estimated surfaces are rendered in three-dimensions. 6) Human activities are tracked and rendered within this virtual three-dimensional world.

The student will work closely with graduate students and postdoctoral fellows at York University, as well as researchers at other institutions involved in the project. The student will develop skills in using MATLAB, a very useful mathematical programming environment, and develop an understanding of basic topics in image processing and vision.

For more information on the laboratory: www.elderlab.yorku.ca

Requirements: Good facility with applied mathematics

Professor James Elder

Estimating Pedestrian and Vehicle Flows from Surveillance Video

Facilities planning at both city (e.g., Toronto) and institutional (e.g., York University) scales requires accurate data on the flow of people and vehicles throughout the environment. Acquiring these data can require the costly deployment of specialized equipment and people, and this effort must be renewed at regular intervals for the data to be relevant.

The density of permanent urban video surveillance camera installations has increased dramatically over the last several years. These systems provide a potential source of low-cost data from which flows can be estimated for planning purposes.

This project will explore the use of computer vision algorithms for the automatic estimation of pedestrian and vehicle flows from video surveillance data. The ultimate goal is to provide planners with accurate, continuous, up-to-date information on facility usage to help guide planning.

For more information on the laboratory: www.elderlab.yorku.ca

Requirements: Good facility with applied mathematics

Professor James Elder

Low-Cost Three-Dimensional Face Scanning System

Low-cost three-dimensional face-scanning systems have a large range of potential applications in security and retail markets. Our laboratory at York University has recently developed a prototype face-scanning system that has the potential for very low-cost mass production. This project involves the development of a second-stage prototype that is one-step closer to commercialization.

The project will involve systems design and development of a specialized real-time 3D face scanner. A combination of hardware and software design will be required. The student will work closely with graduate students and postdoctoral fellows at York University, as well as researchers at other institutions involved in the project. The student will develop skills in both hardware and software design, as well as computer-vision techniques.

For more information on the laboratory: www.elderlab.yorku.ca

Requirements: Interest in both hardware and software design at the systems level.

Professor James Elder

Assisted Target Detection for Airborne Search and Rescue

Human target detection in search-and-rescue and other air-to-ground surveillance applications is an imperfect process. Error rates depend upon the spatial acuity and colour sensitivity of individual observers, and fatigue is known to play a major role. Improved sensing technologies (e.g., range-gated near-IR, thermal IR) have the potential to improve performance. Ultimately, however, performance will be determined by how accurately the vast quantities of data generated by these technologies are interpreted, either by computer or by the human visual system. The goal of the proposed project is to research and develop advanced imaging techniques that will ensure that the power of these diverse sensing technologies is harnessed effectively to yield faster and more reliable detection rates.

The specific goal of the proposed project is to develop algorithms that will improve human target detection rates by drawing visual attention to locations in the data stream where target probability is higher. The SAR simulator at DRDC Toronto will serve as a test-bed for evaluating the efficacy of all image enhancements.

Search and rescue target detection is typically characterized by poor target resolution, variability in data quality due to atmospheric effects etc., and imperfect target knowledge. These challenges suggest a statistical approach in which multiple weak but complementary modalities and cues are combined to produce reliable inferences. We have demonstrated the efficacy of this approach for indoor surveillance (Prince et al., 2005), and our first step will be to transfer these techniques to the search-and-rescue context and evaluate performance on airborne imagery from search-and-rescue flight trials. MATLAB and/or C++ implementations of these algorithms will be transferred from York to Array Systems, who will translate the software into a form suitable for their proprietary Scalable Generic Signal Processor (GSP) technology, and demonstrate target detection at frame rate on a GSP test-bed.

This work may provide leverage in a number of other application areas, including: (1) monitoring of international water and land boundaries, ports and airports, (2) security at critical infrastructure locations (e.g., government buildings, power stations, city cores) and (3) disaster management activities.

For more information on the laboratory: www.elderlab.yorku.ca

Requirements: Good facility with applied mathematics

Professor Hui Jiang

Automatic Retrieval and Normalization of Text data from the Internet

In this project, the student is required to design and write a program which can automatically search, etrieve, and normalize text data from the Internet according to user's queries. The program needs to process each of user's text queries and then search the processed query from some Internet search sites and automatically retrieve and save the returned search results. At last, the program needs to normalize and format the returned text and save them for future uses. Since the program eventually will be used to automatically process a large number of user queries, its efficiency is a key issue in its design and development.

Required skills: basic programming skills; C/shell/Perl is a plus.

Professor Wolfgang Stuerzlinger

Efficient Manipulation of Cloned Objects

Duplication and replication are two simple ways to quickly create larger groups of objects. However, it is typically not possible to manipulate originals and their copies directly (i.e. similar to manipulating a repeated datebook entry). This project investigates new ways to effect the manipulation of replicated/duplicated objects in 2D drawings and evaluating them in a comparative user study.

Platform: any modern GUI toolkit or drawing system

Context Sensitive Cut, Copy & Paste for Code

Many programming errors are due to pieces of code being copied from another location but that has not been "perfectly" adapted to the new context. Such errors are hard to find, especially if the old and new contexts are only subtly different. This project involves fixing some problems in a existing implementation of a context sensitive cut, copy & paste method (in Java), finding some good examples/test cases, and then performing a user study that quantifies how many cut, copy & paste errors are made with & without the technique.

Platform: Java, LAPIS

Improved Suggestions for 2D Drawing Programs

Displaying suggestions during the drawing process can make it easier for the user to create common and desirable configurations. This project investigates novel user interface methods to make such a suggestive user interface easier to use.

Platform: any 2D drawing system, existing C-code for some suggestions.

Automatic Calibration System for Large Displays

Large projected displays often use cameras to allow for interaction (either with touch technologies or laser pointers). However, such systems only work well if the camera is well calibrated to the screen. This calibration needs to be repeated whenever the screen is moved, the projector is changed or the camera is touched. This project uses a camera on a robotic pan/tilt unit to automate this calibration process. It also uses a laser diode and/or a laser range finder to simultaneously detect the planarity of the projection surface as well as increase the accuracy of the calibration.

Wireless Styli as Interaction Devices for Large Displays

This project realizes a novel form of interaction devices for computers. These are wireless styli, which use laser diodes to enable users to point to distant projection surfaces as well as displays in front of the user. A touch detector as well as a novel form of proximity detection enables further forms of interaction.

Robotic Tangible User Interface for Large Tabletops

Tangible user interfaces provide the user with object that they can touch and use as input devices. One example is the use of (tracked) toy houses to perform a city planning task on a large surface. This project implements a new form of tracking/identification scheme for tangible objects via LED arrays mounted on them. Furthermore, and using robotic components, the tangible objects will have the ability to move around autonomously, which enables important functionalities such as undo and replay.

Professor Franck van Breugel

Race Detection with Java Pathfinder

A concurrent program may contain data races. That is, the program may contain concurrent accesses of a particular variable of which at least one is a write. For example, the following Java program contains a data race on the attribute i.

Data races may give rise to unexpected behaviors. For example, for the above program the value read by the Reader can either be 1 or 2. Therefore, it is important to develop tools that can detect races.

Java PathFinder is a model checker developed at NASA. With this tool, one can check properties of Java programs. For Java PathFinder, three different race detectors have been implemented.

The aims of this project are

· to gain a good understanding of data races,

· to develop a test suite to check if the race detectors are correct, and

· to compare the performance of the race detectors.

To accomplish these aims, the student, in collaboration with the supervisor, should

· read some papers/books that discuss race conditions,

· search the literature for small Java programs that contain (apparent) data races,

· write a large collection of small Java programs that contain (apparent) data races, and

· run the test suites for the different race detectors.

Required skills: basic knowledge of Java

Last updated: January 15, 2008.