%人脸检测
close all
clear
clc
I = imread('84.jpg');
% subplot(2,3,1),imshow(I);
%皮肤检测
I=double(I); %整数转化成小数形式
[hue,s,v]=rgb2hsv(I); %RGB空间转化为HSV空间，H：色调 S:饱和度 V：亮度
%将RGB空间转化成 YCrCb空间
cb=0.148*I(:,:,1)-0.291*I(:,:,2)+0.439*I(:,:,3)+128;%饱和度
cr=0.439*I(:,:,1)-0.368*I(:,:,2)-0.071*I(:,:,3)+128;%色调
[w,h]=size(I(:,:,1)); %size of the image
%让皮肤在YCrCb空间的像素点为1
for i=1:w
for j=1:h
%分割肤色区域
if 145<=cr(i,j)&&cr(i,j)<=165&&135<=cb(i,j)&&cb(i,j)<=180&&0.01<=hue(i,j)&&hue(i,j)<=0.15 %区别人脸与狗脸，显示人脸
% if 100<=cr(i,j)&cr(i,j)<=140&150<=cb(i,j)&cb(i,j)<=170&0.01<=hue(i,j)&hue(i,j)<=0.15 %区别人脸与狗脸，显示狗脸
segment(i,j)=1; %skin areas
else
segment(i,j)=0;
end
end
end
% subplot(2,3,2),imshow(segment);
%加工检测区域
skin=segment;
skin=bwareaopen(skin,round(w*h/900)); % 消除小连接的像素<w*h/100的像素
% subplot(2,3,3),imshow(skin);
%dilating 膨胀操作
se=strel('disk',3); %创建一个平坦的圆形结构元素，半径为2
skin=imdilate(skin,se);%膨胀
% subplot(2,3,4),imshow(skin);
% %显示肤色区域
im(:,:,1)=I(:,:,1).*skin;
im(:,:,2)=I(:,:,2).*skin;
im(:,:,3)=I(:,:,3).*skin;
subplot(2,3,5),imshow(uint8(im));
% title('skin areas')
%肤色Cr、Cb范围对检测的影响
%detection of face object
BW = skin;
L = bwlabel(BW,8); %标注各个联通区域
%计算每个连通区域和面积单元的数据转换成数组
BB = regionprops(L, 'BoundingBox'); %计算包含这个区域的最小矩形坐标
BB1=struct2cell(BB); %将各个联通区域坐标转换为元胞组数
BB2=cell2mat(BB1); %将各联通区域元胞数组坐标转换为矩阵
% subplot(2,3,6),imshow(uint8(I));
% title('result image');
%在矩形框中显示目标
[s1, s2]=size(BB2);
for k=3:4:s2-1
% BB2(1,k)wide, BB2(1,k+1)high
% if (BB2(1,k)/BB2(1,k+1)) < 1.6&&.... %显示长脸
% (BB2(1,k)/BB2(1,k+1)) > 0.4 &&....
if (BB2(1,k)/BB2(1,k+1)) < 1.2&&.... %不显示长脸
(BB2(1,k)/BB2(1,k+1)) > 0.8 &&....
(BB2(1,k)*BB2(1,k+1)) > 1000
%长宽比 0.4<W/H<1.8 并且像素数大于1000
hold on;
rectangle('Position',[BB2(1,k-2),BB2(1,k-1),BB2(1,k),BB2(1,k+1)],'EdgeColor','r' )
end
end
