Sobel算子图像边缘提取Matlab代码_matlab_边缘提取

%Function:Simple Edge Detection %Data:3rd Oct.,2008 clc; clear all; close all; %%%%%%%%%%%%%%%% %%% Imread %%% %%%%%%%%%%%%%%%% I0=imread('picturename.jpg'); I=rgb2gray(I0); J0=double(I); J_x=J0; J_y=J0; J=J0; [M,N]=size(I); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%% Sobel Operator Filtering %%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Sobel_x=(1/4)*[-1,-2,-1;0,0,0;1,2,1]; Sobel_y=(1/4)*[-1,0,1;-2,0,2;-1,0,1]; [W_S,W_S]=size(Sobel_x); Half_W_S=(W_S-1)/2; %Filtering with Matrix Sobel_x to Get gx for p=Half_W_S+1:M-Half_W_S for q=Half_W_S+1:N-Half_W_S filter_sum=0; for k=-Half_W_S:Half_W_S for l=-Half_W_S:Half_W_S filter_sum=filter_sum+J0(p+k,q+l)*Sobel_x(k+Half_W_S+1,l+Half_W_S+1); end end J_x(p,q)=filter_sum; end end %Filtering with Matrix Sobel_y to Get gy for p=Half_W_S+1:M-Half_W_S for q=Half_W_S+1:N-Half_W_S filter_sum=0; for k=-Half_W_S:Half_W_S for l=-Half_W_S:Half_W_S filter_sum=filter_sum+J0(p+k,q+l)*Sobel_y(k+Half_W_S+1,l+Half_W_S+1); end end J_y(p,q)=filter_sum; end end %J Indicates the Magnitude of the Gradient J=(J_x.^2+J_y.^2).^(1/2); %%%%%%%%%%%%%%%%%%%%%%%% %%% Edge Detection %%% %%%%%%%%%%%%%%%%%%%%%%%% %Choose a Appropriate T Order_matrix=J(Half_W_S+1:M-Half_W_S,Half_W_S+1:N-Half_W_S); [M_O,N_O]=size(Order_matrix); Order_sequence0=[]; for i=1:M_O Order_sequence0=[Order_sequence0,Order_matrix(i,:)]; end Order_sequence=sort(Order_sequence0); T_location=round(0.95*M_O*N_O); T=Order_sequence(1,T_location); fprintf('\nT=%f\n',T); %Saving the Result Edge Map for m=1:M for n=1:N if J(m,n)>=T J(m,n)=255; else J(m,n)=0; end end end %%%%%%%%%%%%%%%% %%% Figure %%% %%%%%%%%%%%%%%%% subplot(1,2,1); imshow(uint8(I));title('Original Gray Image'); subplot(1,2,2); imshow(uint8(J));title('Edge Detected Image');