Dr.
Shree Nayar, Columbia University
Background Knowledge
Line Fitting Real World
Solution is HOUGH transform
A line in the image corresponds to a point in Parameter (Hough) Space.
A line in the image corresponds to a point in Parameter (Hough) Space.
• Let each edge point in image space vote for a set of possible
parameters in Hough space
• Let each edge point in image space vote for a set of possible
parameters in Hough space
• Accumulate votes in discrete set of bins; parameters with the
most votes indicate line in image space.
(m, c) = (1, 0)
Point in image space is now sinusoid segment in Hough space.
If p can only be positive, then will have to go for 0 to 2Pi. 0 to .
If p can be positive or negative, then only has to go from 0 to Pi or 0 to –Pi. Is .
Natural scene and result of Sobel edge detection followed by thresholding.
Accumulator matrix
Original image and 20 most prominent lines.