An \((r,s; m,n)\)-de Bruijn array is a periodic \(r \times s\) binary array in which each of the different \(m \times n\) matrices appears exactly once. C.T. Fan, S.M. Fan, S.L. Ma and M.K. Siu established a method to obtain either an \((r,2^n;m+1,n)\)-array or a \((2r,2^{n-1};m+1,n)\)-array from an \((r,s; m, n)\)-array. A class of square arrays are constructed by their method. In this paper, decoding algorithms for such arrays are described.