Journal ArticleDOI
Theory of Edge Detection
David Marr,Ellen C. Hildreth +1 more
TLDR
The theory of edge detection explains several basic psychophysical findings, and the operation of forming oriented zero-crossing segments from the output of centre-surround ∇2G filters acting on the image forms the basis for a physiological model of simple cells.Abstract:
A theory of edge detection is presented. The analysis proceeds in two parts. (1) Intensity changes, which occur in a natural image over a wide range of scales, are detected separately at different scales. An appropriate filter for this purpose at a given scale is found to be the second derivative of a Gaussian, and it is shown that, provided some simple conditions are satisfied, these primary filters need not be orientation-dependent. Thus, intensity changes at a given scale are best detected by finding the zero values of delta 2G(x,y)*I(x,y) for image I, where G(x,y) is a two-dimensional Gaussian distribution and delta 2 is the Laplacian. The intensity changes thus discovered in each of the channels are then represented by oriented primitives called zero-crossing segments, and evidence is given that this representation is complete. (2) Intensity changes in images arise from surface discontinuities or from reflectance or illumination boundaries, and these all have the property that they are spatially. Because of this, the zero-crossing segments from the different channels are not independent, and rules are deduced for combining them into a description of the image. This description is called the raw primal sketch. The theory explains several basic psychophysical findings, and the operation of forming oriented zero-crossing segments from the output of centre-surround delta 2G filters acting on the image forms the basis for a physiological model of simple cells (see Marr & Ullman 1979).read more
Citations
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Extensive Turnover of Dendritic Spines and Vascular Remodeling in Cortical Tissues Recovering from Stroke
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Bayesian Modeling of Uncertainty in Low-Level Vision
TL;DR: The uncertainty modeling techniques that are developed, and the utility of these techniques in various applications, support the claim that Bayesian modeling is a powerful and practical framework for low-level vision.
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Analyse d'images: filtrage et segmentation
Philippe Bolon,Jean-Marc Chassery,Jean-Pierre Cocquerez,Didier Demigny,Christine Graffigne,Annick Montanvert,Sylvie Philipp,Rachid Zéboudj,Josiane Zerubia,Henri Maitre +9 more
TL;DR: In this paper, the authors present a comparative study of different techniques for segmentation of images, including filtrage du bruit, extraction of contours, and extraction of regions.
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Medical Image Computing and Computer-Assisted Intervention – MICCAI’99
TL;DR: It is shown that the automated method segments brain and tumor with accuracy comparable to the manual method and with improved reproducibility.
References
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Receptive fields, binocular interaction and functional architecture in the cat's visual cortex
David H. Hubel,Torsten N. Wiesel +1 more
TL;DR: This method is used to examine receptive fields of a more complex type and to make additional observations on binocular interaction and this approach is necessary in order to understand the behaviour of individual cells, but it fails to deal with the problem of the relationship of one cell to its neighbours.
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Receptive fields and functional architecture of monkey striate cortex
David H. Hubel,Torsten N. Wiesel +1 more
TL;DR: The striate cortex was studied in lightly anaesthetized macaque and spider monkeys by recording extracellularly from single units and stimulating the retinas with spots or patterns of light, with response properties very similar to those previously described in the cat.
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The Fourier Transform and Its Applications
TL;DR: In this paper, the authors provide a broad overview of Fourier Transform and its relation with the FFT and the Hartley Transform, as well as the Laplace Transform and the Laplacian Transform.
Book
Digital Picture Processing
Azriel Rosenfeld,Avinash C. Kak +1 more
TL;DR: The rapid rate at which the field of digital picture processing has grown in the past five years had necessitated extensive revisions and the introduction of topics not found in the original edition.
Journal ArticleDOI
Application of fourier analysis to the visibility of gratings
F. W. Campbell,John G. Robson +1 more
TL;DR: The contrast thresholds of a variety of grating patterns have been measured over a wide range of spatial frequencies and the results show clear patterns of uniformity in the response to grating noise.