Assignment #6

2. Create a 256x256 matrix with 1s in the (i, i+1) position and zeros elsewhere using the functions tril(M,k) and triu (M,k).

Octave command:
tril(ones(9),1) - tril(ones(9),0)
ans =



or...

triu(ones(9),1) - triu(ones(9),2)
ans =





3.a) A(:,:,1)=255*ones(100);
A(:,:,2)=255*tril(ones(100));
A(:,:,3)=zeros(100);
imshow(A);



B=double(A)/255;
size(B)

{answer: ans = 100 100 3}

sum(sum(B))/(100*100)

{answer: ans(:,:,1)=1}
ans(:,:,2)=0.505
ans(:,:,3)=0

B=ones(100);
B(:,:,1)=ones(100);
B(:,:,2)=0.505*ones(100);
B(:,:,3)=zeros(100);
imshow(B);
As a result, this is the average colour.






c)Pic 1

A=imread("cocochanel.jpg");
B=double(A)/255;
size(B)
{ans. 74 150 3}

sum(sum(B))/(74*150)

{ans. ans(:,:,1)=0.64490}
ans(:,:,2)=0.54085
ans(:,:,3)=0.63316

C=ones(256);
C(:,:,1)=0.64490*ones(256);
C(:,:,2)=0.54085*ones(256);
C(:,:,3)=0.63316*ones(256);
imshow(C);

This picture's average colour is...



Pic 2


A=imread("recycle.jpg");
B=double(A)/255;
size(B)
{ans. 153 104 3}

sum(sum(B))/(153*104)

{ans. ans(:,:,1)=0.052669}
ans(:,:,2)=0.32379
ans(:,:,3)=0.28915

C=ones(256);
C(:,:,1)=0.052669*ones(256);
C(:,:,2)=0.32379*ones(256);
C(:,:,3)=0.28915*ones(256);
imshow(C);

This picture's average colour is ...