An Approach to Real-Time on Line Visual Inspection

  • Vicenç Llario
  • Jordi Sanromà
Part of the NATO ASI Series book series (volume 63)


In this paper we present some applications of computer vision in well defined industrial environments. In most of those applications the main constraints we have to cope with are, on one hand, real-time response, and on the other hand uncertain illumination conditions intrinsic to this kind of environments. As far as our experience has shown (we suppose everybody has experienced the same), it is very difficult, while developing the vision system in the laboratory, to take into account all the external factors which will influence the performance of the system on the factory floor. Factors such as illumination fluctuations, dirt, noise, vibrations, and high temperatures, among others, will inevitably lead to an unpredictable behavior of the system and as a consequence to a loss of reliability. In order to face those drawbacks we approach every application with a defined methodology which mainly consists of two phases: modelling and design.

During the modelling phase we establish a theoretical model of the process to be inspected as well as the constraints to be considered. This procedure allows us to implement what is commonly called a local analysis of restricted areas of the image by means of special purpose hardware. The principal goal of this process is to attain the best trade-off between speed and reliability.

During the design phase we must choose a strategy consistent with the model in order to guarantee the efficient selection of primitives for the final implementation.


Character Recognition Hough Transform Inspection Process Radon Transform Handwritten Character 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • Vicenç Llario
    • 1
  • Jordi Sanromà
    • 2
  1. 1.RALUXBarcelonaSpain
  2. 2.EROVI, Enginyeria de Robótica i VisióComputer Vision-Image Processing GroupBarcelonaSpain

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