BÀITẬPXỬLÝẢNHSỐ
1) Lọcảnh(sửdụngphéptươngquan)trênmiềnkhônggian
filtered=spatial_filter(image,mask)
Trongđóimagelàảnhxámcầnlọc,masklàmặtnạlọc(kíchthướcmỗichiềulàsốlẻ),
filteredlàảnhsaukhilọc.
Bàilàm:
functionloc_anh=spatial_filter(image,mask)
clc;closeall;
[row_image,colum_image]=size(image);
[row_mask,colum_mask]=size(mask);
fori=1:row_image+2*floor(row_mask/2)
forj=1:colum_image+2*floor(colum_mask/2)
loc_anh(i,j)=0;
end
end
fori=1:row_image
forj=1:colum_image
loc_anh(i+floor(row_mask/2),j+floor(colum_mask/2))=image(i,j);
end
end
fori=1:row_image
forj=1:colum_image
bientam=0;
foru=1:row_mask
forv=1:colum_mask
bientam=bientam+loc_anh(ifloor(row_mask/2)+u,
jfloor(colum_mask/2)+v)*mask(u,v);
end
end
image(i,j)=bientam;
end

function[locmax,locmin,trungvi,midpoint]=locminmax(image,n)
clc;closeall;
[row_image,colum_image]=size(image);
fori=1:row_image+2*floor(n/2)
forj=1:colum_image+2*floor(n/2)
loc_anh(i,j)=0;
end
end
fori=1:row_image
forj=1:colum_image
loc_anh(i+floor(n/2),j+floor(n/2))=image(i,j);
end
end
forI=1:row_image
forj=1:colum_image
max=loc_anh(ifloor(n/2)+1,jfloor(n/2)+1);
min=loc_anh(ifloor(n/2)+1,jfloor(n/2)+1);
foru=1:n
forv=1:n
trung_vi(u,v)=loc_anh(ifloor(n/2)+u,jfloor(n/2)+v);
ifloc_anh(ifloor(n/2)+u,jfloor(n/2)+v)>max
max=loc_anh(ifloor(n/2)+u,jfloor(n/2)+v);
end
ifloc_anh(ifloor(n/2)+u,jfloor(n/2)+v)<min
min=loc_anh(ifloor(n/2)+u,jfloor(n/2)+v);
end
end
end
vector=sort(reshape(trung_vi,1,n*n));
trungvi(i,j)=vector(ceil(n*n/2));

clc;closeall;
[row_image,colum_image]=size(image);n=3;
fori=1:row_image+2*floor(n/2)
forj=1:colum_image+2*floor(n/2)
loc_anh(i,j)=0;
end
end
fori=1:row_image
forj=1:colum_image
loc_anh(i+floor(n/2),j+floor(n/2))=image(i,j);
end
end
fori=1:row_image
forj=1:colum_image
bientam=1;
s=0;
tu=0;
mau=0;
foru=1:n
forv=1:n
bientam=bientam+loc_anh(ifloor(n/2)+u,
jfloor(n/2)+v);
s=s+1/loc_anh(ifloor(n/2)+u,jfloor(n/2)+v);
tu=tu+loc_anh(ifloor(n/2)+u,jfloor(n/2)+v)^(q+1);
mau=mau+loc_anh(ifloor(n/2)+u,jfloor(n/2)+v)^q;
end
end
hinhhoc(i,j)=bientam*(1/n^2);
har(i,j)=n*n/s;
con(i,j)=tu/mau;

functionbai6()
clc;closeall;
origin=imread('D:\Game\anh\Kayle.jpg')
subplot(1,2,1);
imshow(origin),title('Orgin');
laynguong=graythresh(origin);
BlackWhite=im2bw(origin,laynguong);
subplot(1,2,2);
imshow(BlackWhite),title('CatnguongtudongOtsu');
end
7) Hiểnthị8látmặtbitcủamộtảnhxám.
Bàilàm:
functionbai7()
clc;closeall;
origin=imread('D:\Game\anh\Kayle.jpg');
gray=rgb2gray(origin);
subplot(3,3,1),imshow(gray),title('gray');
bit1=bitget(gray,1)*2^0;
subplot(3,3,2),imshow(bit1,[]),title('bit1');
bit2=bitget(gray,2)*2^1;
subplot(3,3,3),imshow(bit2,[]),title('bit2');
bit3=bitget(gray,3)*2^2;
subplot(3,3,4),imshow(bit3,[]),title('bit3');
bit4=bitget(gray,4)*2^3;
subplot(3,3,5),imshow(bit4,[]),title('bit4');
bit5=bitget(gray,5)*2^4;
subplot(3,3,6),imshow(bit5,[]),title('bit5');
bit6=bitget(gray,6)*2^5;
subplot(3,3,7),imshow(bit6,[]),title('bit6');
bit7=bitget(gray,7)*2^6;

functiond=bai9(file)
clc;closeall;
origin=imread('D:\Game\anh\Kayle.jpg');
subplot(3,2,1),imshow(origin),title('origin');
gray=rgb2gray(origin);
subplot(3,2,2),imshow(gray),title('gray');
kenhR=origin(:,:,1);
subplot(3,2,3),imshow(kenhR),title('Red');
kenhG=origin(:,:,2);
subplot(3,2,4),imshow(kenhG),title('Green');
kenhB=origin(:,:,3);
subplot(3,2,5),imshow(kenhB),title('Blue');
trungviR=medfilt2(kenhR,[33]);
trungviG=medfilt2(kenhG,[33]);
trungviB=medfilt2(kenhB,[33]);
rgb_filtered=cat(3,trungviR,trungviG,trungviB);
gray_filtered=medfilt2(gray,[33]);
gray_RGB=rgb2gray(rgb_filtered);
d=abs(gray_RGBgray_filtered);
subplot(3,2,6),imshow(d,[]),title('saikhac');
end
ViếtchươngtrìnhMatlabthựchiệnnhậndạngmộtđốitượngtùyý(1chữcái,chữsố,vậtthể
bấtkỳ,…)
Bàilàm: NhậnDạngKhuônMặt
*Matlab2013cóhàmhỗtrợnhậndạngkhuônmặt.tacóthểsửdụnghàmhỗtrợnàynhưsau:
functionbai10()
%Example1:Facedetection
%
faceDetector=vision.CascadeObjectDetector();%Default:findsfaces
Origin=imread('path_image\.jpg');