gt=nsgabtight(g,a,M); gt=nsgabtight(g,a,M,L);
| g | Cell array of windows |
| a | Vector of time shifts of windows. |
| M | Vector of numbers of channels. |
| L | Transform length. |
| gt | Cell array of canonical tight windows |
nsgabtight(g,a,M) computes the canonical tight windows of the non-stationary discrete Gabor frame defined by windows given in g and time-shifts given by a.
nsgabtight is designed to be used with functions nsdgt and insdgt. Read the help on nsdgt for more details about the variables structure.
The computed tight windows are only valid for the 'painless case', that is to say that they ensure perfect reconstruction only if for each window the number of frequency channels used for computation of nsdgt is greater than or equal to the window length. This correspond to cases for which the frame operator is diagonal.
P. Balazs, M. Dörfler, F. Jaillet, N. Holighaus, and G. A. Velasco. Theory, implementation and applications of nonstationary Gabor frames. J. Comput. Appl. Math., 236(6):1481--1496, 2011. [ .pdf ]