modify1 {DRIP} | R Documentation |
Modify detected edges to make them thin.
modify1(bandwidth, image, edge, plot)
image |
A matrix that represents the image. |
bandwidth |
A positive integer to specify the number of pixels used in the local smoothing. |
edge |
A matrix of 0 and 1 represents detected edge pixels. |
plot |
If plot = TRUE, images of detected edges before the modification and after the modification are plotted. |
A local-smoothing based edge detection algorithm may flag deceptive edge
pixel candidates. One kind of such candidates consists of those close
to the real edges. They occur due to the nature of local
smoothing. That is, if the point (x_i, y_j)
is flagged,
then its neighboring pixels will be flagged with high probability.
This kind of deceptive candidates can make the detected edges
thick. This modification procedure makes the detected edges
thin.
Returns a matrix of zeros and ones of the same size as edge.
Qiu, P. and Yandell, B., "Jump detection in regression surfaces," Journal of Computational and Graphical Statistics 6(3), 1997, 332-354.
data(sar) # SAR image is bundled with the package and it is a
# standard test image in statistics literature.
edge = stepEdgeLCK(sar, 4, 20)
out = modify1(4, sar, edge)