You can try something like this. If you think about what you're trying to do is create stripes based on degrees. And how do we get degrees in an image. by performing the arctan of pixel location based off a reference point.
halfI = zeros(1024,512);
x = 1:size(halfI,2);
y = 1:size(halfI,1);
[x y]=meshgrid(x,y);
Ang = flipud(atand(y./x));
figure,imagesc(Ang),colormap(gray),axis equal , axis tight
So here we have the angle for each pixel position from the horizontal and bottom left corner.
So how do we get stripes? well we define how wide each stripe is in angles and then alternate each one
dtheta = 2;
stripes = 0:dtheta:90;
for ind = 1:2:length(stripes)-1;
halfI(stripes (ind)<Ang & stripes (ind+1)>Ang)=1;
end
figure,imagesc(halfI),colormap(gray),axis equal , axis tight
So now we have half the image.
Img = ~[fliplr(halfI) halfI];
figure,imagesc(Img),colormap(gray), axis , axis tight
Center stripe is doubly thick in my example but i'll let you figure out that part.