邊緣檢測sobel算法:
原理:略(哈哈)
clc;
clear;
imag = imread('1.jpg'); %讀取關鍵幀
imag = rgb2gray(imag); %轉化爲灰度圖
figure,imshow(imag);
title('原圖');
gx = [-1 -2 -1;0 0 0;1 2 1];
gy = [-1 0 1;-2 0 2;-1 0 1];
[high,width] = size(imag); % 獲得圖像的高度和寬度
imag1 = double(imag);
uSobel = zeros(high,width);
for i = 2:high - 1 %sobel邊緣檢測
for j = 2:width - 1
Gx = sum(sum(gx.*imag1(i-1:i+1, j-1:j+1))); %先求行和,再求列和
Gy = sum(sum(gy.*imag1(i-1:i+1, j-1:j+1)));
uSobel(i,j) = sqrt(Gx^2 + Gy^2);
end
end
uSobel=mat2gray(uSobel);%將matrix值映射到[0,1],歸一化
figure,imshow(uSobel);
title('邊緣檢測後'); %畫出邊緣檢測後的圖像
% Matlab自帶函數邊緣檢測
% K爲獲取得到的關鍵幀的灰度圖
BW3 = edge(imag,'sobel', 0.09);
figure,imshow(BW3,[]);
title('Matlab自帶函數邊緣檢測');