near8detect.m

利用matlab对图像进行读入与处理（运用在仿真领域）

function [near_points,A]=near8detect(A,points,t)
%检测出与颜色小于t的点集points的8领域中有哪些点
%不包括points中的点
%检测过的点的象素值全部变为255
near_points=[];
row_A=size(A,1);column_A=size(A,2);
for i=1:size(points,1)
    for ii=points(i,1)-1:points(i,1)+1
        for jj=points(i,2)-1:points(i,2)+1
            if ii<=0 | jj<=0  | ii>=row_A | jj>=column_A%防止领域出界
                continue;
            end
            if ii==jj
                A(ii,jj)=255;
            elseif A(ii,jj)<=t
                near_points=[near_points;ii,jj];
                A(ii,jj)=255;
            end
        end
    end
end