annotate dsp/imagspec.m @ 47:82075c94eed1
adding a bunch of stuff, including graphics and pitch toolboxes.
| author |
samer |
| date |
Sat, 17 Jan 2015 15:20:35 +0000 |
| parents |
c3b0cd708782 |
| children |
|
| rev |
line source |
|
samer@32
|
1 function X=imagspec(A,P)
|
|
samer@32
|
2 % IMAGSPEC - convert mag/phase spectrum to wave
|
|
samer@32
|
3 %
|
|
samer@32
|
4 % imagspec :: [[M+1,L]]~'magnitude', [[M+1,L]]~'phase' -> [[2*M,L]]~'signal'.
|
|
samer@32
|
5 % imagspec :: [[M+1,L]]~'magnitude' -> [[2*M,L]]~'signal'.
|
|
samer@32
|
6 %
|
|
samer@32
|
7 % Second form uses random phases.
|
|
samer@32
|
8
|
|
samer@32
|
9 n=size(A,1);
|
|
samer@32
|
10 if nargin<2,
|
|
samer@32
|
11 % make up random phases
|
|
samer@32
|
12 P=exp(2*i*pi*rand(size(A)));
|
|
samer@32
|
13 end
|
|
samer@32
|
14 A=[A; A(n-1:-1:2,:)];
|
|
samer@32
|
15 phi=[P; conj(P(n-1:-1:2,:))];
|
|
samer@32
|
16 X=real(ifft(phi.*A)); % get waveform
|
|
samer@32
|
17
|
|
samer@32
|
18
|
|
samer@32
|
19
|
