%% Interpolace
I = imread('bla.tif');
[M,N]=size(I);
figure(1)
imshow(I), title('RAW snimek');
J=zeros(512,768,3,'uint8');

% zobrazeni jen pomoci RGB kanalu
J(2:2:end,1:2:end,3)=I(2:2:end,1:2:end);
J(1:2:end,1:2:end,2)=I(1:2:end,1:2:end);
J(2:2:end,2:2:end,2)=I(2:2:end,2:2:end);
J(1:2:end,2:2:end,1)=I(1:2:end,2:2:end);
figure(2)
imshow(J), title('RGB snimek');
figure(3)
%opocitavani zbylych slozek pomoci posouvani matice
new_green=zeros(M-2,N-2,'double');
new_green=new_green+(im2double(J(2:end-1,1:end-2, 2)))/4; %doprava
new_green=new_green+(im2double(J(2:end-1,3:end, 2)))/4; %doleva
new_green=new_green+(im2double(J(1:end-2,2:end-1, 2)))/4;%nahoru
new_green=new_green+(im2double(J(3:end,2:end-1, 2)))/4;%dolu
G_vrstva=new_green+im2double(J(2:end-1,2:end-1,2)); %suma puvodnich a dopocitanych slozek
subplot(131),imshow(G_vrstva), title('G snimek'); %G vrstva

new_blue=zeros(M-2,N-2,'double');
new_blue=new_blue+(im2double(J(2:end-1,1:end-2, 3)))/2;%doprava
new_blue=new_blue+(im2double(J(2:end-1,3:end, 3)))/2;%doleva
new_blue=new_blue+(im2double(J(3:end,2:end-1, 3)))/2;%dolu
new_blue=new_blue+(im2double(J(1:end-2,2:end-1, 3)))/2;%nahoru
new_blue=new_blue+(im2double(J(1:end-2,3:end, 3)))/4;
new_blue=new_blue+(im2double(J(3:end,3:end, 3)))/4;
new_blue=new_blue+(im2double(J(3:end,1:end-2, 3)))/4;
new_blue=new_blue+(im2double(J(1:end-2,1:end-2, 3)))/4;
B_vrstva=new_blue+im2double(J(2:end-1,2:end-1,3)); %suma puvodnich a dopocitanych slozek
subplot(132),imshow(B_vrstva), title('B snimek');

new_red=zeros(M-2,N-2,'double');
new_red=new_red+(im2double(J(2:end-1,1:end-2, 1)))/2;%doprava
new_red=new_red+(im2double(J(2:end-1,3:end, 1)))/2;%doleva
new_red=new_red+(im2double(J(3:end,2:end-1, 1)))/2;%dolu
new_red=new_red+(im2double(J(1:end-2,2:end-1, 1)))/2;%nahoru
new_red=new_red+(im2double(J(1:end-2,3:end, 1)))/4;
new_red=new_red+(im2double(J(3:end,3:end, 1)))/4;
new_red=new_red+(im2double(J(3:end,1:end-2, 1)))/4;
new_red=new_red+(im2double(J(1:end-2,1:end-2, 1)))/4;
R_vrstva=new_red+im2double(J(2:end-1,2:end-1,1));  %suma puvodnich a dopocitanych slozek
subplot(133),imshow(R_vrstva), title('RAW snimek');

new_I=zeros(M-2,N-2,3);
new_I(:,:,1)=R_vrstva;
new_I(:,:,2)=G_vrstva;
new_I(:,:,3)=B_vrstva;
figure(4)
imshow(new_I), title('Snimek po interpolaci')