Q#3(ii) Picture

Q#3(b)
Average Colour of second image

Octave Commands
octave-3.0.0.exe:47> a=imread("pic2.jpg");
octave-3.0.0.exe:48> b=double(a)/255;
octave-3.0.0.exe:49> size(b)
ans =

541 500 3

octave-3.0.0.exe:50> c=sum(sum(b))/(541*500)
c =

ans(:,:,1) = 0.56223
ans(:,:,2) = 0.62916
ans(:,:,3) = 0.65633


octave-3.0.0.exe:51> d=ones(256);
octave-3.0.0.exe:52> d(:,:,1)=0.56223*ones(256);
octave-3.0.0.exe:53> d(:,:,2)=0.62916*ones(256);
octave-3.0.0.exe:54> d(:,:,3)=0.65633*ones(256);
octave-3.0.0.exe:55> imshow(d);

Assignment#6 Q3

Q#3(c)

Average colour of two assigned pictures
For this assignment Paul helped me alot in downloading assigned pictures.
pkg load image
a=imread("pic1.jpg");
b=double(a)/255;

avgb=sum(sum(b))/(650*780)

c=ones(256);
c(:,:,1)=0.95854*ones(256);
c(:,:,2)=0.95091*ones(256);
c(:,:,3)=0.94792*ones(256);
imshow(c)

Q#3a continued..

Average of colours
octave-3.0.0.exe:14> sum(sum(A))/100/100,
ans =

ans(:,:,1) = 1
ans(:,:,2) = 0.50500
ans(:,:,3) = 0


octave-3.0.0.exe:15> imshow(sum(A));

Assignment #6 Q3

Q#3 Detrmine the average color
a) R=ones(100); G=tril(ones(100));, B=zeros(100);
Ans:
octave-3.0.0.exe:5> A(:,:,1)=ones(100);
octave-3.0.0.exe:6> A(:,:,2)=tril(ones(100));
octave-3.0.0.exe:7> A(:,:,3)=zeros(100);
octave-3.0.0.exe:8> imshow(A);

Assignment #6 Q2

Q#2 create a 256 X 256 matrix with in (i,i+1) position and zeros elsewhere
Octave Commands:
A= zeros(256);
for i=1:256;
A(i,i+1)=1;
end;
imshow(A);
or
octave-3.0.0.exe:8> A=tril(ones(256),1);
octave-3.0.0.exe:9> B=tril(ones(256),0);
octave-3.0.0.exe:10> imshow(A-B);

Question#3c

Big T 7pi/4
Octave Command
bigT=255*ones(256);
bigT(30:79,64:191)=zeros(50,128);
bigT(50:199,111:146)=zeros(150, 36);
for x = 1:256
for y = 1:256
newy=rem(2*x+y,256)+1;
bigTskew(x,y)=bigT(x,newy);
end;
end;
for x=1:256;
for y=1:256;
bigTskewrotate(x,y)=bigTskew(mod(round(x*cos(7*pi/4)-y*sin(7*pi/4)),256)+1, mod(round(x*sin(7*pi/4)+y*cos(7*pi/4)),256)+1);
end;
end;
imshow(bigTskewrotate);

Question #3 b

BigT for S=1
Octave commandoctave-3.0.0.exe:5>
octave-3.0.0.exe:5> bigT=255*ones(256);
octave-3.0.0.exe:6> bigT(30:79,64:191)=zeros(50,128);
octave-3.0.0.exe:7> bigT(50:199,111:146)=zeros(150,36);
octave-3.0.0.exe:8>
octave-3.0.0.exe:8> # as given from assignment question...
octave-3.0.0.exe:8>
octave-3.0.0.exe:8> for x=1:256
> for y=1:256
> xnew=x;
> ynew=mod((2*x+y),256)+1;
> newbigT(xnew,ynew)=bigT(x,y);
> endfor
> endfor
octave-3.0.0.exe:9>
octave-3.0.0.exe:9> imshow(newbigT)
octave-3.0.0.exe:10>

Q#3

Q#3
Image of Big T
Part a)

bigT=255*ones(256);
bigT(30:79,64:191)=zeros(50,128);
bigT(50:199,111:146)=zeros(150,36);
imshow(bigT);

Assignment #5 Q#2

Q#2:Give octave commands to draw the top part of figure 6.4 in the book
Ans:


Octave commands:

octave-3.0.0.exe:34> C=zeros(256);
octave-3.0.0.exe:35> functionC=circle(x,y)
error: `circle' undefined near line 35 column 11
error: evaluating assignment expression near line 35, column 10
octave-3.0.0.exe:35> function C=circle(x,y)
> for i=1:256
> for j=1:256
> if (i-x)^2+(j-y)^2 <=2500
> C(i,j)=1;
> else
> C(i,j)=0;
> endif
> endfor
> endfor
> endfunction
octave-3.0.0.exe:36> C(:,:,1)=circle(142,103);
octave-3.0.0.exe:37> C(:,:,2)=circle(99,128);
octave-3.0.0.exe:38> C(:,:,3)=circle(142,153);
octave-3.0.0.exe:39> imshow(C)
octave-3.0.0.exe:40> imshow(C);

Q#16

Q#16 Display the YM face of the colour cube


Octave command are
YM(:,:,1)=ones(256);
YM(:,:,2)=[ones(256,1)*[0:1:255]/255];
YM(:,:,3)=[ones(256,1)*[255:-1:0]/255]';
Imshow(YM);

Question # 15,

Q #15 Display the CM face of the colour cube
Octave Command
CM(:,:,1)=[ones(256,1)*[0:1:255]/255];
CM(:,:,3)=ones(256);
CM(:,:,2)=[ones(256,1)*[0:1:255]/255]';
imshow(CM)

Q#13, 14

Display the GB face of the colour cube
GB(:,:,1) = Zeros(256);
GB(:,:,2)=[ones(256,1)*[256:-1:0]/255];
GB(:,;,3)=[ones(256,1)*[255:-1:0]/255]';
imshow(GB)



Q#14 Show the CY face of colour cube
Octave Commands:
CY(:,:,1)=[ones(256,1)*[255:-1:0]/255]';
CY(:,:,2)=ones(256);
CY(:,:,3)=[ones(256,1)*[0:1:255]/255];
imshow(CY);

Q#12

Display the RG face of the colour cube
Octave Commands are RG(:,:,1)=[ones(256,1)*[0:1:255]/255];
RG(:,:,2)=[ones(256,1)*[0:1:255]/255];'
RG(:,:,3)= zeros(256);
imshow(RG)

Assignment#4 Q11

RB(:,:,1)=[ones(256,1)*[0:1:255]/255]';
RB(:,:,2)=zeros(256);
RB(:,:,3)=[ones(256,1)*[0:1:255]/255];
imshow(RB)

Assignment #4Q11