Hello!
I need your help to 'conditionally' modify the pixels around an arbitrary selected point/pixel at (x,y) using Matlab. First, please see the following 3 x 3 grid.
top-left (x-1,y-1);
top-middle (x,y-1);
top-right (x+1,y-1);
middle-left (x-1,y);
middle-middle(x,y);
middle-right (x+1,y);
bottom-left (x-1,y+1);
bottom-middle(x,y+1);
bottom-right (x+1,y+1);
As can be seen, in the following code - and thanks to a previously requested/obtained help - I could only modify the pixels at 8 locations adjacent to (x,y) but when I set the following conditions,
sdh = 0;
sdv = 0;
sdh = abs((1/4)*(Y(1:end-2,1:end-2)-Y(1:end-2,3:end)) + (1/2)*(Y(2:end-1,1:end-2)-Y(2:end-1,3:end)) + (1/4)*(Y(3:end,1:end-2)-Y(3:end,3:end)));
sdv = abs((1/4)*(Y(1:end-2,1:end-2)-Y(3:end,1:end-2)) + (1/2)*(Y(1:end-2,2:end-1)-Y(3:end,2:end-1)) + (1/4)*(Y(1:end-2,3:end)-Y(3:end,3:end)));
if if sdh >= sdv
(x+1,y) = (1/2)*((x+1,y)+(x+2,y));
(x,y+1) = (1/2)*((x,y+1)+(x,y+2));
and
if sdh < sdv
(x,y-1) = (1/2)*((x,y-1)+(x,y-2));
(x,y+1) = (1/2)*((x,y+1)+(x,y+2));
I can't modify the pixels at the locations (x+1,y) & (x-1,y) when sdh >= sdv; and, at the locations (x,y-1) & (x,y+1) when sdh < sdv, as indicated above. Can you please have a look at the following code and help me, if possible ?
N = 8;
E = [46,38];
X = magic(N);
Y = false(N+2);
for k = 1:numel(E);
Y(2:end-1,2:end-1) = X==E(k);
Z = Y(1:end-2,2:end-1) | Y(3:end,2:end-1) | Y(2:end-1,3:end) | Y(2:end-1,1:end-2) | Y(1:end-2,1:end-2) | Y(1:end-2,3:end) | Y(3:end,1:end-2) | Y(3:end,3:end);
X(Z) = E(k);
end
