clear
x = randn(1, 65536);
x = x / max(abs(x));
wavwrite(x, 8000, 16, 'noise.wav')
!./sox -V noise.wav -r 44100 nup_rate.wav rate
!./sox -V noise.wav -r 44100 nup_poly.wav polyphase
!./sox -V noise.wav -r 44100 nup_resamp.wav resample
x_rate = wavread('nup_rate.wav');
x_poly = wavread('nup_poly.wav');
x_resamp = wavread('nup_resamp.wav');
XR = 20*log10(abs(fft(2*hanning(65536).*x_rate(1:65536), 65536)));
XP = 20*log10(abs(fft(2*hanning(65536).*x_poly(1:65536), 65536)));
XS = 20*log10(abs(fft(2*hanning(65536).*x_resamp(1:65536), 65536)));
w = [0:65535]/65536 * 44100;
plot(w, XR,  w, XP, w, XS)
axis([0 22050 -100 80])
legend('Linear','Polyphase','Resample')
l = line([4000 4000], [-100 80]);
set(l, 'Color', 'g')
st = text(5000, -50, '4 kHz: Upper Limit of Data');
l = line([44100 - 4000 44100 - 4000], [-100 80]);
set(l, 'Color', 'g')
title('Rate Convert From 8 kHz to 44.1 kHz Of Random Noise');
ylabel('Magnitude of Spectrum in dB')
xlabel('Frequency in kHz');
xlabel('Frequency in Hz');
print -dppm -painters -r0 RandomNoiseUpsample.ppm
plot(w, XR)
axis([0 22050 -100 80])
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Linear Interpolation, Rate Conversion From 8 kHz to 44.1 kHz Of Random Noise');
l = line([4000 4000], [-100 80]);
set(l, 'Color', 'g')
XM = max(XR);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'g')
set(l, 'Color', 'r')
XM = max(XR(floor(5000/44100*65536):floor(20000/44100*65536)));
l = line([0 22050], [XM XM]);
delete(l)
XM = max(XR(floor(10000/44100*65536):floor(20000/44100*65536)));
l = line([0 22050], [XM XM]);
set(l, 'Color', 'y')
set(l, 'Color', 'c')
axis([0 22050 -100 80])
l = line([4000 4000], [-100 80]);
set(l, 'Color', 'g')
print -dppm -painters -r0 RandomNoiseUpsampleLinear.ppm
plot(w, XS)
l = line([4000 4000], [-100 80]);
set(l, 'Color', 'g')
axis([0 22050 -100 80])
delete(l)
l = line([4000 4000], [-100 80]);
delete(l)
l = line([4001 3990], [-100 80]);
set(l, 'Color', 'g')
delete(l)
l = line([4000 4000], [-100 80]);
delete(l)
l = line([4000 4001], [-100 80]);
set(l, 'Color', 'g')
XM = max(XR);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Bandlimited Interpolation (sox-12.16), Rate Conversion From 8 kHz to 44.1 kHz of Random Noise');
XM = max(XS(floor(10000/44100*65536):floor(20000/44100*65536)));
l = line([0 22050], [XM XM]);
set(l, 'Color', 'c')
print -dppm -painters -r0 RandomNoiseUpsampleResample.ppm
plot(w, XP)
l = line([4000 4001], [-100 80]);
set(l, 'Color', 'g')
axis([0 22050 -100 80])
XM = max(XP);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
XM = max(XP(floor(10000/44100*65536):floor(20000/44100*65536)));
l = line([0 22050], [XM XM]);
set(l, 'Color', 'c')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Polyphase Interpolation, Rate Conversion From 8 kHz to 44.1 kHz of Random Noise');
print -dppm -painters -r0 RandomNoiseUpsamplePolyphase.ppm
t = [0:65535]/8000;
x = sin(2*pi*500*t) + sin(2*pi*1000*t) + sin(2*pi*1500*t) + sin(2*pi*2000*t) + sin(2*pi*2500*t) + sin(2*pi*3000*t) + sin(2*pi*3500*t) + sin(2*pi*3900*t);
x = x / max(abs(x));
wavwrite(x, 8000, 16, 'sine.wav');
x = wavread('sine.wav');
X = 20*log10(abs(fft(2*hanning(65536).*x(1:65536), 65536)));
w = [0:65535]/65536 * 8000;
plot(w,X)
axis([0 4000 -100 80])
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Input Sine Wave Spectrum');
% X = 20*log10(abs(fft(2*hanning(65536)'.*x(1:65536), 65536)));
% plot(w,X)
% axis([0 4000 -100 80])
% xlabel('Frequency in Hz');
% ylabel('Magnitude of Spectrum in dB')
% title('Input Sine Wave Spectrum');
print -dppm -painters -r0 SineWaveInput.ppm
!./sox -V sine.wav -r 44100 s_rate.wav rate
!./sox -V sine.wav -r 44100 s_poly.wav polyphase
!./sox -V sine.wav -r 44100 s_resamp.wav resample
s_rate = wavread('s_rate.wav');
s_poly = wavread('s_poly.wav');
s_resamp = wavread('s_resamp.wav');
SR = 20*log10(abs(fft(2*hanning(65536).*s_rate(1:65536), 65536)));
SP = 20*log10(abs(fft(2*hanning(65536).*s_poly(1:65536), 65536)));
SS = 20*log10(abs(fft(2*hanning(65536).*s_resamp(1:65536), 65536)));
w = [0:65535]/65536*44100;
plot(w,SR, w, SP, w, SS)
axis([0 22050 -100 80])
legend('Linear','Polyphase','Resample')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Rate Conversion From 8 kHz to 44.1 kHz of Sine Waves');
print -dppm -painters -r0 SineWaveOutput.ppm
plot(w, SR)
axis([0 22050 -100 80])
l = line([4000 4001], [-100 80]);
delete(l)
l = line([4000 4001], [-100 80]);
set(l, 'Color', 'g')
XM = max(XR);
l = line([0 4000], [XM XM]);
delete(l)
XM = max(SR);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
XM = max(SR(floor(10000/44100*65536):floor(20000/44100*65536)));
l = line([0 22050], [XM XM]);
set(l, 'Color', 'c')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Linear Interpolation, Rate Conversion From 8 kHz to 44.1 kHz of Sine Waves');
print -dppm -painters -r0 SineWaveLinear.ppm
plot(w, SP)
axis([0 22050 -100 80])
XM = max(SP);
l = line([4000 4001], [-100 80]);
set(l, 'Color', 'g')
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
XM = max(SP(floor(10000/44100*65536):floor(20000/44100*65536)));
l = line([0 22050], [XM XM]);
set(l, 'Color', 'c')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Polyphase Interpolation, Rate Conversion From 8 kHz to 44.1 kHz of Sine Waves');
print -dppm -painters -r0 SineWavePolyphase.ppm
plot(w, SS)
l = line([4000 4001], [-100 80]);
axis([0 22050 -100 80])
set(l, 'Color', 'g')
XM = max(SS);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
XM = max(SS(floor(10000/44100*65536):floor(20000/44100*65536)));
l = line([0 22050], [XM XM]);
set(l, 'Color', 'c')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Bandlimited Interpolation (sox-12.16), Rate Conversion From 8 kHz to 44.1 kHz of Sine Waves');
print -dppm -painters -r0 SineWaveResample.ppm
x = randn(1, 65536 * 6);
x = x / max(abs(x));
wavwrite(x, 44100, 16, 'noise2.wav');
!./sox -V noise2.wav -r 8000 ndown_rate.wav rate
!./sox -V noise2.wav -r 8000 ndown_resamp.wav resample
!./sox -V noise2.wav -r 8000 test.raw polyphase
!./sox -c 1 -r 8000 -s -w test.raw ndown_poly.wav
n_rate = wavread('ndown_rate.wav');
n_poly = wavread('ndown_poly.wav');
n_resamp = wavread('ndown_resamp.wav');
NR = 20*log10(abs(fft(2*hanning(65536).*n_rate(1:65536), 65536)));
NP = 20*log10(abs(fft(2*hanning(65536).*n_poly(1:65536), 65536)));
NS = 20*log10(abs(fft(2*hanning(65536).*n_resamp(1:65536), 65536)));
w = [0:65535]/65536*8000;
plot(w, NR, w, NP, w, NS)
axis([0 4000 -100 80])
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Rate Conversion From 44.1 kHz to 8 kHz of Random Noise');
legend('Linear','Polyphase','Resample')
print -dppm -painters -r0 RandomNoiseDownsample.ppm
plot(w,NR)
axis([0 4000 -100 80])
l = line([4000 4001], [-100 80]);
delete(l)
l = line([4000 4001], [-30 40]);
delete(l)
l = line([4000 4001], [-30 50]);
set(l, 'Color', 'g')
XM = max(NR);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Linear Interpolation, Rate Conversion From 44.1 kHz to 8 kHz of Random Noise');
print -dppm -painters -r0 RandomNoiseDownsampleLinear.ppm
plot(w,NP)
axis([0 4000 -100 80])
l = line([4000 4001], [-30 50]);
set(l, 'Color', 'g')
XM = max(NP);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Polyphase Interpolation, Rate Conversion From 44.1 kHz to 8 kHz of Random Noise');
print -dppm -painters -r0 RandomNoiseDownsamplePolyphase.ppm
plot(w,NS)
axis([0 4000 -100 80])
l = line([4000 4001], [-30 50]);
l = line([4000 4001], [-30 40]);
plot(w,NS)
axis([0 4000 -100 80])
l = line([4000 4001], [-30 40]);
set(l, 'Color', 'g')
XM = max(NS);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Bandlimited Interpolation (sox-12.16), Rate Conversion From 44.1 kHz to 8 kHz of Random Noise');
print -dppm -painters -r0 RandomNoiseDownsampleResample.ppm
t = [0:65535*6] / 44100;
NumFreqs = floor(22050 / 500) - 1;
x = zeros(size(t));
for k = 1:NumFreqs
x = x + sin(k*2*pi*500*t);
end
x = x / max(abs(x));
wavwrite(x, 44100, 16, 'sineup.wav');
x = wavread('sineup.wav');
X = 20*log10(abs(fft(2*hanning(65536).*x(1:65536), 65536)));
w = [0:65535]/65536*44100;
plot(w,X)
axis([0 22050 -100 80])
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Input Sine Wave Spectrum');
print -dppm -painters -r0 InputSineWaveUp.ppm
!./sox -V sineup.wav -r 8000 sdown_rate.wav rate
!./sox -V sineup.wav -r 8000 test.raw polyphase
!./sox -V sineup.wav -r 8000 sdown_resamp.wav resample
!./sox -c 1 -r 8000 -s -w test.raw sdown_poly.wav
sdown_rate = wavread('sdown_rate.wav');
sdown_poly = wavread('sdown_poly.wav');
sdown_resamp = wavread('sdown_resamp.wav');
SR = 20*log10(abs(fft(2*hanning(65536).*sdown_rate(1:65536), 65536)));
SP = 20*log10(abs(fft(2*hanning(65536).*sdown_poly(1:65536), 65536)));
SS = 20*log10(abs(fft(2*hanning(65536).*sdown_resamp(1:65536), 65536)));
w = [0:65535]/65536 * 8000;
plot(w, SR, w, SP, w, SS)
axis([0 4000 -100 80])
legend('Linear','Polyphase','Resample')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Rate Conversion From 44.1 kHz to 8 kHz of Sine Waves');
print -dppm -painters -r0 SineWaveDownSample.ppm
plot(w,SR)
axis([0 4000 -100 80])
XM = max(SR);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([4000 4001], [-100 80]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Linear Interpolation, Rate Conversion From 44.1 kHz to 8 kHz of Sine Waves');
print -dppm -painters -r0 SineWaveDownSampleLinear.ppm
plot(w,SP)
axis([0 4000 -100 80])
l = line([4000 4001], [-100 80]);
set(l, 'Color', 'g')
XM = max(SS);
XM = max(SP);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Polyphase Interpolation, Rate Conversion From 44.1 kHz to 8 kHz of Sine Waves');
print -dppm -painters -r0 SineWaveDownSamplePolyphase.ppm
plot(w,SS)
axis([0 4000 -100 80])
l = line([4000 4001], [-100 80]);
set(l, 'Color', 'g')
XM = max(SS);
l = line([0 4000], [XM XM]);
set(l, 'Color', 'g')
l = line([0 4000], [XM - 3 XM - 3]);
set(l, 'Color', 'r')
xlabel('Frequency in Hz');
ylabel('Magnitude of Spectrum in dB')
title('Bandlimited Interpolation (sox-12.16), Rate Conversion From 44.1 kHz to 8 kHz of Sine Waves');
print -dppm -painters -r0 SineWaveDownSampleResample.ppm