conv2 discrete 2-D convolution. Syntax C = conv2(A,B [,shape]) C = conv2(hrow,hcol,B [,shape]) Parameters hrow a real or complex vector. hcol a real or complex vector. A a real or complex 2-D array. B a real or complex 2-D array. shape an optional character string with possible values: "full", conv2 computes the full two-dimensional convolution. It is the default value. "same", conv2 computes the central part of the convolution of the same size as A. "valid", conv2 computes the convolution parts without the zero-padding of A. C a real or complex 2-D array. Description conv2 uses a straightforward formal implementation of the two-dimensional convolution equation in spatial form. C=conv2(A,B [,shape]) computes the two-dimensional convolution of the arrays A and B: With shape=="full" the dimensions of the resultC are given by size(A)+size(B)+1. The indices of the center element of B are defined as floor((size(B)+1)/2). With shape=="same" the dimensions of the resultC are given by size(A). The indices of the center element of B are defined as floor((size(B)+1)/2). With shape=="valid" the dimensions of the result C are given by size(A)-size(B)+1) if and(size(A)-size(B))>=0 else C is empty . The indices of the center element of B are defined as [1 1] . The separable form C=conv2(hrow,hcol,B [,shape])is equivalent to C=conv2(hrow(:)*hcol(:).',B [,shape]) . Note that convol2d can be more efficient for large arrays. Examples See Also convol2d conv History 5.4.0 Function conv2 introduced.