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Spherical gradient operator
Author(s) -
Li Shigang
Publication year - 2013
Publication title -
ieej transactions on electrical and electronic engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.254
H-Index - 30
eISSN - 1931-4981
pISSN - 1931-4973
DOI - 10.1002/tee.21919
Subject(s) - sobel operator , pixel , operator (biology) , computer science , computer vision , contrast (vision) , artificial intelligence , mathematics , spherical coordinate system , image (mathematics) , algorithm , edge detection , mathematical analysis , image processing , biochemistry , chemistry , repressor , transcription factor , gene
In this paper, a spherical gradient operator is proposed that computes the gradient from a discrete spherical image with irregular pixels. In contrast to the conventional methods which approximate spherical pixels as regular hexagons, the proposed method can cope with irregular pixels and compute the gradient vector relative to the camera coordinate system directly. We also show that the conventional Sobel operator can be treated as a special case of the proposed approach. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.