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Method for High-Speed Detection of Edges of an Image

IP.com Disclosure Number: IPCOM000119934D
Original Publication Date: 1991-Mar-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 1 page(s) / 25K

Publishing Venue

IBM

Related People

Saitoh, F: AUTHOR

Abstract

Described is a method for detecting edges of an image at high speed. The Roberts operator is used in combination with a Sobel or Prewit operator to increase processing efficiency.

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Method for High-Speed Detection of Edges of an Image

      Described is a method for detecting edges of an image at
high speed.  The Roberts operator is used in combination with a Sobel
or Prewit operator to increase processing efficiency.

      Sobel and Prewit operators are well-known in the art as means
for detecting edges and calculating directions of edges of an image.
However, since they have coefficients arranged in a matrix of 3 x 3,
they require much time to process the whole image.

      To avoid this problem, Roberts operator is used in combination
with a Sobel or Prewit operator.  The Roberts operator includes
coefficients arranged in a 2 x 2 matrix and thus requires less time
for porcessing.  In processing, the Roberts operator is first used
for detection of image edges.  Only when the value detected with the
Roberts operator is higher than a threshold, the Sobel or Prewit
operator is executed.  When the value with the Roberts operator is
lower than the threshold, the Soble or Prewit operator is not done.

      By using this method, it is possible to detect edges and their
directions rapidly and accurately.