Machine Vision and Applications

, Volume 13, Issue 5–6, pp 275–285 | Cite as

Wood inspection with non-supervised clustering

  • Olli Silvén
  • Matti Niskanen
  • Hannu Kauppinen
Original paper

Abstract. The appearance of sawn timber has huge natural variations that the human inspector easily compensates for mentally when determining the types of defects and the grade of each board. However, for automatic wood inspection systems these variations are a major source for complication. This makes it difficult to use textbook methodologies for visual inspection. These methodologies generally aim at systems that are trained in a supervised manner with samples of defects and good material, but selecting and labeling the samples is an error-prone process that limits the accuracy that can be achieved. We present a non-supervised clustering-based approach for detecting and recognizing defects in lumber boards. A key idea is to employ a self-organizing map (SOM) for discriminating between sound wood and defects. Human involvement needed for training is minimal. The approach has been tested with color images of lumber boards, and the achieved false detection and error escape rates are low. The approach also provides a self-intuitive visual user interface.

Key words: Self-organizing map – user interface – color – texture 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Olli Silvén
    • 1
  • Matti Niskanen
    • 1
  • Hannu Kauppinen
    • 1
  1. 1.Department of Electrical Engineering, University of Oulu, P.O.B. 4500, 90015 Oulu, Finland; e-mail: Olli.Silven@ee.oulu.fi FI

Personalised recommendations