waveFile = 'soo.wav';
au=myAudioRead(waveFile);
startIndex=15000;
frameSize=256;
endIndex=startIndex+frameSize-1;
frame=au.signal(startIndex:endIndex);
opt=frame2pdf('defaultOpt');
opt.maxShift=length(frame);
opt.useShift=0;
acf0=frame2pdf(frame, opt);
opt.useSift=1;
[acf1, frameEstimated, excitation]=frame2pdf(frame, opt);

subplot(3,1,1)
plot(1:frameSize, [frame, frameEstimated]);
legend('Original Signal', 'LPC estimate');
title('Original signal vs. LPC estimate');
subplot(3,1,2);
plot(1:frameSize, excitation);
grid on
title(['Residual signal when order = ', int2str(opt.siftOrder)]);
subplot(3,1,3);
plot(1:frameSize, [acf0/max(acf0), acf1/max(acf1)]);
grid on
title('Normalized ACF curves'); xlabel('Frame index');
legend('Normalized ACF on original frame', 'Normalized ACF on excitation');