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File:Quantization nodither noshaping spectrum.png

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    English: Spectrum of a 750 Hz pure tone sampled at 48 kHz and quantized to 4 bits using neither dither nor noise shaping. 
    % quantization_nodither_noshaping.m
% Quantization demo using neither dither nor noise shaping.
% Authors: Fatbag
% License: Public domain (no warranties)

rand('state', 0xdeadbeef);

f_s = 48000; % sampling rate (samples/sec)
f0 = 750; % frequency of sine wave (Hz)

t_s = 1/f_s; % sampling period (sec/sample)
w0 = 2*pi*f0; % angular frequency of sine wave (Hz)

t = (0 : 4095) * t_s;

x = round(15*sin(w0*t));

figure 1;
plot(t(1:ceil(2*f_s/f0)), x(1:ceil(2*f_s/f0)));
axis([0, ceil(2*f_s/f0)*t_s, -20, 20]);
grid on;
xlabel('t');
ylabel('x(t)');

figure 2;
X = fft(x(1:4096));
X = X(1:2048);
m = 20*log10(arrayfun(@norm, X));
m -= max(m);
m(~isfinite(m)) = -1000;
f = (0:2047)/2048*f_s/2;
plot(f, m);
axis([0, f_s/2, -100, 0]);
grid on;
xlabel('Frequency (Hz)');
ylabel('Relative power (dB)');
print 'quantization_nodither_noshaping_spectrum_uncropped.png';
    Date
    Source Own work
    Author Andrew D'Addesio

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    I, the copyright holder of this work, hereby publish it under the following license:
    Creative Commons CC-Zero This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication.
    The person who associated a work with this deed has dedicated the work to the public domain by waiving all of their rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law. You can copy, modify, distribute and perform the work, even for commercial purposes, all without asking permission.

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