how to solve this error

i am using 2d dual tree discrete wavelet transform while running afb2d.m i got error like this Undefined function or method 'afb2D_A' for input arguments of type 'uint8' in [L, H] = afb2D_A(x, af1, 1);

[Walter Roberson]

duplicates http://www.mathworks.com/matlabcentral/answers/62126-2d-dual-tree-dicrete-wavelet-transform