About the project
The acronym NAT stands for Nonlinear and Adaptive Techniques in digital image processing, analysis and computer vision, an Esprit Basic Research Activity funded by the European Union. The partners in the activity are :
- Aristotle University of Thessaloniki, led by Professor Ioannis Pitas, who is also the overall project coordinator.
- Technical University of Hamburg-Harburg, led by Professor Hans Burkhardt.
- Tampere University of Technology, led by Dr. Moncef Gabbouj.
- University of Trieste, led by Professor Giovanni Sicuranza.
- University of Strathclyde, led by Dr. Stephen Marshall.
Nonlinear techniques in digital image processing and analysis have exhibited a tremendous growth in the past decade. Their use has been a successful alternative for the cases where the classical linear techniques fail. In this project, the application of nonlinear techniques in BW image processing and analysis, in image sequence processing as well as in color image processing are studied. Another important issue examined in the project is nonlinear digital filter adaptation. Novel adaptation algorithms are derived and novel adaptive nonlinear structures are investigated, coming from the merging of nonlinear filter families and neural networks. The aim of this project is to enhance the research efforts of the participating groups in the area of nonlinear and adaptive systems and techniques. The following nonlinear filter classes are studied: polynomial filters, order statistic filters and morphological filters. Adaptation methods for these filter classes are developed. Neural networks techniques are used for filter adaptation and digital image processing and analysis. All the above mentioned filters and their adaptive variations are used for :
- multichannel (color) image processing and image sequence processing
- motion adaptive filtering schemes
- image restoration
In the case of nonlinear digital image analysis and computer vision, two approaches are investigated: mathematical morphology techniques and nonlinear position invariant transforms. Several of the above mentioned nonlinear techniques are prime candidates for parallel implementation. Parallel implementations are studied for all nonlinear processing and analysis schemes to be developed within this project.
So far, the project has produced novel contributions in all of the above mentioned areas. It has also addressed the need for a unifying theory for the various nonlinear filter classes by the interaction and exchange of research results in the various filter classes. Furthermore, the application of these nonlinear techniques in certain key-technology areas (e.g. color image processing, image sequence processing) has helped in the comparative study of these techniques and has produced a clear leading-edge technological output. Finally, the parallelisation of algorithms for nonlinear digital image processing and analysis will continue to contribute to the development of fast parallel unifying methods and architectures for this particular area.
NAT Consortium
Prof. Ioannis Pitas,
Dept. of Informatics,
Aristotle University of Thessaloniki,
P.O. Box 451, GR-54006 Thessaloniki, Greece
e-mail pitas@csd.auth.gr
Prof. Hans Burkhardt,
Technical University of Hamburg-Harburg,
P.O. Box 901052, 2100 Hamburg 90, Germany
e-mail burkhardt@tu-harburg.d400.de
Dr. Stephen Marshall,
Dept. Electronic & Electrical Eng,
University of Strathclyde,
204 George St, Glasgow, G1 1XW. UK
e-mail s.marshall@eee.strath.ac.uk
Dr. Moncef Gabbouj, Tampere University of Technology,
P.O. Box 553, 33101 Tampere, Finland
e-mail moncef@cs.tut.fi
Prof. Giovanni Sicuranza,
University of Trieste,
Via A. Valerio 10, 34127 Trieste, Italy
e-mail sicuranza@univ.trieste.it
NAT-related conferences and courses
- The NAT sponsored 1995 IEEE Workshop on Nonlinear Signal and Image Processing was held on 20-22 June 1995, at Porto Carras, Greece. The workshop proceedings are available in on-line form.
- A course on ‘Recent Advances in Image Processing’ will be held in the Department of Information and Communication Sciences at the University of Technology Hamburg-Harburg in Hamburg on 4-8 September 1995 – presented by instructors from five European Universities active in the field of image processing research. In addition, practical sessions will be given by invited speakers from industry. The course will be spread over five days and will include formal lectures complemented by ‘hands on’ sessions, as well as a visit to the Mikroelektronik Anwendungszentrum Hamburg GmbH (MAZ). Social events will also be arranged in conjunction with the course, including a Reception at the City Hall of Harburg. All attendees will be given a comprehensive set of lecture notes.
The NAT newsletter
NATTER, the NAT newsletter, presents some of the advances made by the groups involved. So far, the following issues have been published, which can be viewed by clicking the highlighted words DOS or Unix, depending on the type of host your Web browser runs on :