shithub: libsamplerate

ref: 6240d2560db1c0f0642a0c6e4a2dbb3cc3ae887a
dir: /FIR-POLY/timeline.m/

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function [t, mt, w] = timeline (len, stretch)


if (stretch < 0 || stretch > 1)
	error ("stretch out of range [0, 1].\n");
	endif

# Mofified time

x_w = 0.2 ;
x = [-0.5 -0.2 0.2 0.5];
y = [-0.5 -0.4 -0.1 0.5];

p = polyfit (x, y, 4);

t = linspace (-0.5, 0.5, 100);
y = polyval (p,t);
plot (t, y)
return

mt = ((1 - stretch) * t + stretch  * t.^2) - 0.5 ;


# Basically a Nuttall indow
ak = [0.42323 0.49755 0.07922] ;

w = zeros (1, len) ;

k = 0 ;
for a = ak,
	w = w + a * cos (2 * pi * k * mt) ;
	k += 1 ;
	endfor

w = fliplr (w / len) ;

# Linear t

t = linspace (-(len-2)/2, (len-2)/2, len) / len ;


end

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