examp_hermite.m

Matlab时频分析工具箱,希望能对大家有所帮助啊

% Setup the basic parameters of the Gabor system.

% This program is free software: you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
% 
% This program is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
% GNU General Public License for more details.
% 
% You should have received a copy of the GNU General Public License
% along with this program.  If not, see <http://www.gnu.org/licenses/>.

L=480;  % Length of signal.
a=40;   % Time shift.
M=12;   % Number of modulations.

% Number of Hermite functions to use
R=4;

% Create a multiwindow Gabor window using
% the R first Hermite functions.
g=pherm(L,0:R-1);

% Create a Gabor frame object.
gf=tfr_create('dgt',a,M,g,'candual');

% Alternatively, the following call would have created
% the same object, in a more flexible manner.
%
% gf=tfr_create('dgt',a,M,{'pherm',0:R-1},'candual');

% Test that analysis and synthesis works.

f=rand(L,1);
c=tfr_ar(gf,f);
fr=tfr_sr(gf,c);

disp('');
disp('Norm of reconstruction, should be close to zero.');
norm(f-fr)

% Get the analysis and synthesis windows
g  = tfr_get_win(gf,'a',L);
gd = tfr_get_win(gf,'s',L);

% Clear the object again.
tfr_clear(gf);

% Plot some spetrograms of the Hermite functions.
figure(1);

subplot(2,2,1);
sgram(g(:,1),'nf','tc','lin');
zoom(2);

subplot(2,2,2);
sgram(g(:,2),'nf','tc','lin');
zoom(2);

subplot(2,2,3);
sgram(g(:,3),'nf','tc','lin');
zoom(2);

subplot(2,2,4);
sgram(g(:,4),'nf','tc','lin');
zoom(2);

% Plot some spetrograms of the dual of the 
% Hermite functions.
figure(2);

subplot(2,2,1);
sgram(gd(:,1),'nf','tc','lin');
zoom(2);

subplot(2,2,2);
sgram(gd(:,2),'nf','tc','lin');
zoom(2);

subplot(2,2,3);
sgram(gd(:,3),'nf','tc','lin');
zoom(2);

subplot(2,2,4);
sgram(gd(:,4),'nf','tc','lin');
zoom(2);