lidandan08
2008-05-23, 21:27
各位大侠们,本人现急于交论文,以前也没学过MATLAB,在网上下的程序不怎么懂,运行结果不太对,望高手们指教!:cry: :cry:
程序如下:
%PCA人脸识别
imgdata=[];%训练图像矩阵
for i=1:40
for j=1:5
a=imread(strcat('C:\Documents and Settings\Administrator\桌面\orl\s',num2str(i),'\',num2str(j),'.jpg'));
% imshow(a);
b=a(1:112*92); % b是行矢量 1×N,其中N=10304
b=double(b);
imgdata=[imgdata; b]; % imgdata 是一个M * N 矩阵,imgdata中每一行数据一张图片,M=200
end;
end;
imgdata=imgdata'; %每一列为一张图片
imgmean=mean(imgdata,2); % 平均图片,N维列向量
for i=1:200
minus(:,i) = imgdata(:,i)-imgmean; % minus是一个N*M矩阵,是训练图和平均图之间的差值
end;
covx=minus'* minus; % M * M 阶协方差矩阵
[COEFF, latent,explained] = pcacov(covx'); %PCA,用协方差矩阵的转置来计算以减小计算量
%选择构成95%的能量的特征值
i=1;
proportion=0;
while(proportion < 95)
proportion=proportion+explained(i);
i=i+1;
end;
p=i-1;
% 训练得到特征脸坐标系
i=1;
while (i<=p && latent(i)>0)
base(:,i) = latent(i)^(-1/2)*minus * COEFF(:,i); % base是N×p阶矩阵,用来进行投影,除以latent(i)^(1/2)是对人脸图像的标准化
i = i + 1;
end
% 将训练样本对坐标系上进行投影,得到一个 p*M 阶矩阵为参考
reference = base'*minus;
accu = 0;
accu = 0; %计算准确度
% 测试过程
for i=1:40
for j=6:10 %读入40 x 5 副测试图像
a=imread(strcat('C:\Documents and Settings\Administrator\桌面\orl\s',num2str(i),'\',num2str(j),'.jpg'));
b=a(1:10304);
b=double(b);
b=b';
object = base'*(b-imgmean);
distance=100000;
%最小距离法,寻找和待识别图片最为接近的训练图片
for k=1:200
temp= norm(object - reference(:,k));
if (distance > temp)
which = k;
distance = temp;
end;
end;
temp1 = which/5;
if (temp1 == floor(temp1))
left = (temp1-1)*5;
right = temp1*5;
else
left = floor(temp1)*5;
right = ceil(temp1)*5;
end;
if (((i-1)*5+j-5>left)&&((i-1)*5+j-5<=right)) %正确识别
accu = accu+1;
end;
end;
end;
accuracy=accu/200 %输出识别率
程序如下:
%PCA人脸识别
imgdata=[];%训练图像矩阵
for i=1:40
for j=1:5
a=imread(strcat('C:\Documents and Settings\Administrator\桌面\orl\s',num2str(i),'\',num2str(j),'.jpg'));
% imshow(a);
b=a(1:112*92); % b是行矢量 1×N,其中N=10304
b=double(b);
imgdata=[imgdata; b]; % imgdata 是一个M * N 矩阵,imgdata中每一行数据一张图片,M=200
end;
end;
imgdata=imgdata'; %每一列为一张图片
imgmean=mean(imgdata,2); % 平均图片,N维列向量
for i=1:200
minus(:,i) = imgdata(:,i)-imgmean; % minus是一个N*M矩阵,是训练图和平均图之间的差值
end;
covx=minus'* minus; % M * M 阶协方差矩阵
[COEFF, latent,explained] = pcacov(covx'); %PCA,用协方差矩阵的转置来计算以减小计算量
%选择构成95%的能量的特征值
i=1;
proportion=0;
while(proportion < 95)
proportion=proportion+explained(i);
i=i+1;
end;
p=i-1;
% 训练得到特征脸坐标系
i=1;
while (i<=p && latent(i)>0)
base(:,i) = latent(i)^(-1/2)*minus * COEFF(:,i); % base是N×p阶矩阵,用来进行投影,除以latent(i)^(1/2)是对人脸图像的标准化
i = i + 1;
end
% 将训练样本对坐标系上进行投影,得到一个 p*M 阶矩阵为参考
reference = base'*minus;
accu = 0;
accu = 0; %计算准确度
% 测试过程
for i=1:40
for j=6:10 %读入40 x 5 副测试图像
a=imread(strcat('C:\Documents and Settings\Administrator\桌面\orl\s',num2str(i),'\',num2str(j),'.jpg'));
b=a(1:10304);
b=double(b);
b=b';
object = base'*(b-imgmean);
distance=100000;
%最小距离法,寻找和待识别图片最为接近的训练图片
for k=1:200
temp= norm(object - reference(:,k));
if (distance > temp)
which = k;
distance = temp;
end;
end;
temp1 = which/5;
if (temp1 == floor(temp1))
left = (temp1-1)*5;
right = temp1*5;
else
left = floor(temp1)*5;
right = ceil(temp1)*5;
end;
if (((i-1)*5+j-5>left)&&((i-1)*5+j-5<=right)) %正确识别
accu = accu+1;
end;
end;
end;
accuracy=accu/200 %输出识别率