comparison code Kat/hpsmodel.m @ 1:881c3acf1164

matlab code Kat
author Katerina <katkost@gmail.com>
date Sat, 20 Apr 2013 12:35:51 +0100
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0:59c6861155d9 1:881c3acf1164
1 function [y,yh,ys,fr0] = hpsmodel(x,fs,w,N,t,nH,minf0,maxf0,f0et,maxhd,stocf)
2 %=> analysis/synthesis of a sound using the sinusoidal harmonic model
3 % x: input sound, fs: sampling rate, w: analysis window (odd size),
4 % N: FFT size (minimum 512), t: threshold in negative dB,
5 % nH: maximum number of harmonics, minf0: minimum f0 frequency in Hz,
6 % maxf0: maximim f0 frequency in Hz,
7 % f0et: error threshold in the f0 detection (ex: 5),
8 % maxhd: max. relative deviation in harmonic detection (ex: .2)
9 % stocf: decimation factor of mag spectrum for stochastic analysis
10 % y: output sound, yh: harmonic component, ys: stochastic component
11 M = length(w); % analysis window size
12 Ns = 1024; % FFT size for synthesis
13 H = 256; % hop size for analysis and synthesis
14 N2 = N/2+1; % half-size of spectrum
15 soundlength = length(x); % length of input sound array
16 hNs = Ns/2; % half synthesis window size
17 hM = (M-1)/2; % half analysis window size
18 pin = max(hNs+1,1+hM); % initialize sound pointer to middle of analysis window
19 pend = soundlength-max(hM,hNs); % last sample to start a frame
20 fftbuffer = zeros(N,1); % initialize buffer for FFT
21 yh = zeros(soundlength+Ns/2,1); % output sine component
22 ys = zeros(soundlength+Ns/2,1); % output residual component
23 w = w/sum(w); % normalize analysis window
24 sw = zeros(Ns,1);
25 ow = triang(2*H-1); % overlapping window
26 ovidx = Ns/2+1-H+1:Ns/2+H; % overlap indexes
27 sw(ovidx) = ow(1:2*H-1);
28 bh = blackmanharris(Ns); % synthesis window
29 bh = bh ./ sum(bh); % normalize synthesis window
30 wr = bh; % window for residual
31 sw(ovidx) = sw(ovidx) ./ bh(ovidx);
32 sws = H*hanning(Ns); % synthesis window for stochastic
33
34 i = 0;
35 while pin<pend
36 i = i+1;
37 %-----analysis-----%
38 xw = x(pin-hM:pin+hM).*w(1:M); % window the input sound
39 fftbuffer(1:(M+1)/2) = xw((M+1)/2:M); % zero-phase window in fftbuffer
40 fftbuffer(N-(M-1)/2+1:N) = xw(1:(M-1)/2);
41 X = fft(fftbuffer); % compute the FFT
42 mX = 20*log10(abs(X(1:N2))); % magnitude spectrum
43 pX = unwrap(angle(X(1:N/2+1))); % unwrapped phase spectrum
44 ploc = 1 + find((mX(2:N2-1)>t) .* (mX(2:N2-1)>mX(3:N2)) ...
45 .* (mX(2:N2-1)>mX(1:N2-2))); % find peaks
46 [ploc,pmag,pphase] = peakinterp(mX,pX,ploc); % refine peak values
47 f0 = f0detection(mX,fs,ploc,pmag,f0et,minf0,maxf0); % find f0
48 fr0(i)=f0;
49 hloc = zeros(nH,1); % initialize harmonic locations
50 hmag = zeros(nH,1)-100; % initialize harmonic magnitudes
51 hphase = zeros(nH,1); % initialize harmonic phases
52 hf = (f0>0).*(f0.*(1:nH)); % initialize harmonic frequencies
53 hi = 1; % initialize harmonic index
54 npeaks = length(ploc); % number of peaks found
55 while (f0>0 && hi<=nH && hf(hi)<fs/2) % find harmonic peaks
56 [dev,pei] = min(abs((ploc(1:npeaks)-1)/N*fs-hf(hi))); % closest peak
57 if ((hi==1 || ~any(hloc(1:hi-1)==ploc(pei))) && dev<maxhd*hf(hi))
58 hloc(hi) = ploc(pei); % harmonic locations
59 hmag(hi) = pmag(pei); % harmonic magnitudes
60 hphase(hi) = pphase(pei); % harmonic phases
61 end
62 hi = hi+1; % increase harmonic index
63 end
64 hloc(1:hi-1) = (hloc(1:hi-1)~=0).*((hloc(1:hi-1)-1)*Ns/N+1); % synth. locs
65 ri= pin-hNs; % input sound pointer for residual analysis
66 xr = x(ri:ri+Ns-1).*wr(1:Ns); % window the input sound
67 Xr = fft(fftshift(xr)); % compute FFT for residual analysis
68 Yh = genspecsines(hloc(1:hi-1),hmag,hphase,Ns); % generate sines
69 Yr = Xr-Yh; % get the residual complex spectrum
70 mYr = abs(Yr(1:Ns/2+1)); % magnitude spectrum of residual
71 %mYs = stochenvelope(mYr,stocf);
72 %-----transformations-----%
73 mYsenv = decimate(mYr,stocf,1); % decimate the magnitude spectrum
74 %-----synthesis-----%
75 mYs = interp(mYsenv,stocf,1); % interpolate to original size
76
77 % n=1:N/2+1;
78 % plot(n/N*Ns,mX); %plotting the original spectrum
79 % hold on;
80 % plot(20*log10(abs(mYs)), 'r'); %plotting the approximation done by the decimate function
81 %
82 % hold on;
83 % plot(hloc, hmag, 'g*');
84 % hold off;
85 % pause
86
87 roffset = ceil(stocf/2)-1; % interpolated array offset
88 mYs = [ mYs(1)*ones(roffset,1); mYs(1:Ns/2+1-roffset) ];
89 pYs = 2*pi*rand(Ns/2+1,1); % generate phase random values
90 mYs1 = [mYs(1:Ns/2+1); mYs(Ns/2:-1:2)]; % create magnitude spectrum
91 pYs1 = [pYs(1:Ns/2+1); -1*pYs(Ns/2:-1:2)]; % create phase spectrum
92 Ys = mYs1.*cos(pYs1)+1i*mYs1.*sin(pYs1); % compute complex spectrum
93 yhw = fftshift(real(ifft(Yh))); % sines in time domain using IFFT
94 ysw = fftshift(real(ifft(Ys))); % stoc. in time domain using IFFT
95 yh(ri:ri+Ns-1) = yh(ri:ri+Ns-1)+yhw(1:Ns).*sw; % overlap-add for sines
96 ys(ri:ri+Ns-1) = ys(ri:ri+Ns-1)+ysw(1:Ns).*sws; % overlap-add for stoch.
97 pin = pin+H; % advance the sound pointer
98 end
99
100 %ys=tanh(10*ys);
101 y= yh+ys; % sum sines and stochastic