New Plugins - Canny Edge Detector
divyar...@gmail.com
1. Gaussian High Pass Filter (MIT'S FFTW based)
2. Canny Edge Detector
*********************************
*********************************
Gaussian High Pass Filter (MIT'S FFTW based)
This plugin extends the MIT's FFTW based plugin by D. Rathore to
implement a Gaussian High Pass Filter. It demonstratess how to perform
convolution in Frequency Domain.
A high-pass filter is a filter that passes high frequencies well, but
attenuates (or reduces) frequencies lower than the cutoff frequency
[Reference: Wikipedia]. High values of the input parameter (distance
from the origin/center) result in edge detection.
Submitted July 01, 2006
Updated January 29, 2007 by Ajanta Trivedi ( Department of
Mathematics, IIT Roorkee, India).
*********************************
*********************************
Canny Edge Detector
Canny edge detection uses linear filtering with a gaussian kernel to
smooth the noise and then computes the edge strength and direction for
each pixel in the smoothed image. This is done by dividing the image
in two orthogonal directions. The Canny edge detector asks the user to
input three parameteres : SIGMA, Threshold (LOW) and Threshold (HIGH).
Shows how the Plugin Development Kit can enhance the usability of
algorithms.
Reference: http://marathon.csee.usf.edu/edge/edge_detection.html ; M.
Heath, S. Sarkar, T. Sanocki, and K.W. Bowyer, "A Robust Visual Method
for Assessing the Relative Performance of Edge-Detection Algorithms"
IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol.
19, No. 12, December 1997, pp. 1338-1359.
Submitted July 01, 2007
Updated July 04, 2007 by Prabhjot Kaur (Maharana Pratap Engineering
College, Kanpur).