gamma=wildual(g,M); gamma=wildual(g,M,L);
| g | Gabor window. |
| M | Number of modulations. |
| L | Length of window. (optional) |
| gamma | Canonical dual window. |
wildual(g,M) returns the dual window of the Wilson or WMDCT basis with window g, parameter M and length equal to the length of the window g.
The window g may be a vector of numerical values, a text string or a cell array. See the help of wilwin for more details.
If the length of g is equal to \(2\cdot M\) then the input window is assumed to be an FIR window. In this case, the dual window also has length of \(2\cdot M\). Otherwise the smallest possible transform length is chosen as the window length.
wildual(g,M,L) does the same, but now L is used as the length of the Wilson basis.
The input window g must be real and whole-point even. If g is not whole-point even, then reconstruction using the dual window will not be perfect. For a random window g, the window closest to g that satisfies these restrictions can be found by
g_wpe = real(peven(g));
All windows in the toolbox satisfies these restrictions unless clearly stated otherwise.