Hello,
I am trying to use the conv2 function to convolute a matrix with a filter for the creation of a convolutional neural network. Take the following 3 by 3 matrix:
A = [1 2 3; 4 5 6; 7 8 9];
and the filter:
B = [1 0; 0 1];
For a stride of 1, my understanding of convolution from the examples I have seen is that the output should be (1*1) + (0*2) + (0*4) + (5*1) = 6 for the first element in the resulting matrix and (1*2) + (0*3) + (0*5) + (1*6) = 8 for the second element and so on until the filter reaches the bottom lower half of A for a final result of
ans = [6 8; 12 14];
when I use the conv2 function my results is:
conv2(A,B) = [1 2 3 0 4 6 8 3 7 12 14 6 0 7 8 9];
where my expected answer is in the middle of the output. Where do these extra numbers come from?
Best Answer