I'm struggling to understand something. So far I understood this : x is 3x3 matrix and W is a 2x2 matrix
a) extend W to be a 4X9 matrix and flatten x to be 9x1
b) multiply the Toeplitz matrix and the vector
the part that I don't understand is how can do the same thing with an 400 * 400 image grayscaled before and 3x3 filter.
x = 400 * 400
w = 3 * 3
h = 9 * 160 000
x_flatten = 160 000
output = x_flatten * h ??
I can't figure it out how can I play with the shape to achieve the same principles to be able to retrieve my image after