我正在尝试在 MATLAB中实现本文中介绍的广义霍夫变换。我也尝试使用这个文档来理解算法。我一直在弄清楚如何计算梯度角以找到要在 R 表中使用的 Φ。
我试图运行这个matlab 实现，但轮廓函数试图访问负索引。缺少的功能如下。
距离.m
function [ d ] = distance( x1, y1, x2, y2 )
d = sqrt( (x2-x1)^2 + (y2-y1)^2 );
end
重心.m
function [ xo, yo ] = barycenter( img )
% gravitational center coordinates of a shape
[rows, cols] = size(img);
x = ones(rows, 1)*(1:cols);
y = (1:rows)'*ones(1,cols);
area = sum(sum(img));
xo = sum(sum(double(img) .* x)) / area;
yo = sum(sum(double(img) .* y)) / area;
end
模型霍夫.m
function [H]=ModelHough(imgRGB)
% Generalized Hough Transform Modeling
% Image Binarization
imgBW = rgb2gray(imgRGB);
imgBI = imgBW < 255;
% Retrieving information about the contour: points and number (N)
N = contour(imgBI);
% Model initialization:
% row = beta value * 100
% column = number of the couple (alpha, distance)
% 3rd dimension: 1 = alpha, 2 = distance
H=zeros(round(100*2*pi),N,2);
% Compute of the barycenter coordinates
[ xo, yo ] = barycenter(imgBI);
% for each contour point
for i=1:N
% beta compute for ith contour point
b = beta(N, imgBI, i);
% research of the first column
k=1;
while H(b+1,k,2)~=0
k=k+1;
end
% compute of the alpha value
H(b+1, k, 1) = alpha(N, i, imgBI);
% compute of the distance value
H(b+1, k, 2) = distance( xo, yo, i, b );
end