Daniel@0: function points=FMPoints(len, freq, fmFreq, fmAmp, fs)
Daniel@0: % points=FMPoints(len, freq, fmFreq, fmAmp, fs)
Daniel@0: % Generates (fractional) sample locations for frequency-modulated impulses
Daniel@0: %     len         = number of samples
Daniel@0: %     freq        = pitch frequency (Hz)
Daniel@0: %     fmFreq      = vibrato frequency (Hz)  (defaults to 6 Hz)
Daniel@0: %     fmAmp       = max change in pitch  (defaults to 5% of freq)
Daniel@0: %     fs          = sample frequency     (defaults to 22254.545454 samples/s)
Daniel@0: %
Daniel@0: % Basic formula: phase angle = 2*pi*freq*t + (fmAmp/fmFreq)*sin(2*pi*fmFreq*t)
Daniel@0: %     k-th zero crossing approximately at sample number
Daniel@0: %     (fs/freq)*(k - (fmAmp/(2*pi*fmFreq))*sin(2*pi*k*(fmFreq/freq)))
Daniel@0: 
Daniel@0: % (c) 1998 Interval Research Corporation  
Daniel@0: 
Daniel@0: if nargin<2,
Daniel@0:    fprintf('Format: sig=fmPoints(len, freq [, fmAmp, fmFreq, sampleRate])\n');
Daniel@0:    return;
Daniel@0:    end;
Daniel@0: if nargin<5,
Daniel@0:    fs=22254.545454;
Daniel@0:    end;
Daniel@0: if nargin<4,
Daniel@0:    fmAmp=0.05*freq;
Daniel@0:    end;
Daniel@0: if nargin<3,
Daniel@0:    fmFreq=6;
Daniel@0: end;
Daniel@0: 
Daniel@0: kmax=fix(freq*(len/fs));
Daniel@0: points=0:kmax-1;
Daniel@0: points=1+(fs/freq)*(points-(fmAmp/(2*pi*fmFreq))* ...
Daniel@0: sin(2*pi*(fmFreq/freq)*points));