3 double images stored in a matrix

I have 3 images of size 256 x 256, i want to stored them in a matrix 65536 x 3 double

Answer 1

[Kevin Holly]

m1 = rand(256);
m2 = rand(256);
m3 = rand(256);

size(m1)

ans = 1×2

256 256

size(m1(:))

ans = 1×2

65536 1

M(:,1) = m1(:);
M(:,2) = m2(:);
M(:,3) = m3(:);

size(M)

ans = 1×2

65536 3

[Irwan Setiawan]

thank you for the answer