How do I calculate the compression ratio of my LPC code.

%MAIN BODY
clear all;
clc;

%TAKING INPUT WAVEFILE,
inpfilenm = 'a1.wav';
[y, Fs] =audioread(inpfilenm); 

% x=wavrecord(,);
%LENGTH (IN SEC) OF INPUT WAVEFILE,
t=length(y)./Fs;
sprintf('Processing the wavefile "%s"', inpfilenm)
sprintf('The wavefile is  %3.2f  seconds long', t)

%THE ALGORITHM STARTS HERE,
M=10;  %prediction order
[aCoeff, pitch_plot, voiced, gain] = f_ENCODER(y, Fs, M);  %pitch_plot is pitch periods
synth_speech = f_DECODER (aCoeff, pitch_plot, voiced, gain);

Answer 1

[Shubh]

Hi,

The compression ratio is a measure of how much the data has been reduced in size after applying a compression algorithm. In this case, I assumed a simple compression model where the original signal is represented by LPC (Linear Predictive Coding) coefficients. Here's the complete code:

%MAIN BODY
clear all;
clc;

% TAKING INPUT WAVEFILE
inpfilenm = 'a1.wav';
[y, Fs] = audioread(inpfilenm);

% LENGTH (IN SEC) OF INPUT WAVEFILE
t = length(y) / Fs;
sprintf('Processing the wavefile "%s"', inpfilenm)
sprintf('The wavefile is %3.2f seconds long', t)

% THE ALGORITHM STARTS HERE
M = 10;  % prediction order
[aCoeff, pitch_plot, voiced, gain] = f_ENCODER(y, Fs, M);  % pitch_plot is pitch periods
synth_speech = f_DECODER(aCoeff, pitch_plot, voiced, gain);

% CALCULATING COMPRESSION RATIO
original_size = numel(y) * 2 * 8;  % 16 bits per sample
encoded_size = numel(aCoeff) * 8;   % assuming each coefficient is 64 bits

compression_ratio = original_size / encoded_size;
disp(['Compression Ratio: ', num2str(compression_ratio)]);

The compression ratio is then displayed using "disp(['Compression Ratio: ', num2str(compression_ratio)]);".

Hope this helps!

[Mert Sari]

Thanks, its work.