Delete deceptive edge pixels that are scattered in the design space.
Usage
modify2(bandwidth, edge, plot)
Value
A matrix of zeros and ones of the same size as the input image.
Arguments
bandwidth
A positive integer that specifies the number of
pixels to use in the local smoothing.
edge
A matrix of 0 and 1 representing the detected edge
pixels.
plot
If plot = TRUE, images of the detected edges before
and after the modification are plotted.
Details
A local-smoothing based edge detection algorithm may flag deceptive edge
pixel candidates. One kind of such candidates existis due to the nature of hypothesis
testing, on which the threshold value of the edge detection criterion is
based. That is, a point \((x_i, y_j)\) could be flagged as a edge
pixel with certain probability, even if it is actually not a edge pixel.
Deceptive candidates of this kind are scattered in the whole design
space. This modification procedure deletes scattered edge pixel candidates.
References
Qiu, P. and Yandell, B. (1997) "Jump Detection in Regression Surfaces,"
Journal of Computational and Graphical Statistics6(3),
332-354, tools:::Rd_expr_doi("10.1080/10618600.1997.10474746").