I want to eliminate spurious peaks of Hilbert transform for finding glottal closure in the linear prediction (LP) residual. I have the following 4 steps:
- Hilbert Transform.
- Identify Peaks in Hilbert Transform.
- Consider this hypothesis that time gap between two successive glottal closure instance is not likely to vary in the adjacent pitch period.
Case 3 would help to find peaks such as candidate and spurious peaks. However case 4 improve our results for best peaks candidate for glottal closure.
I have written the following MATLAB code:
e_downsample = downsample(e,2); DFT=fft(e); hilbert_e=ifft(complex(imag(DFT(1:(length(DFT)/2))),real(DFT(1:(length(DFT)/2))))); h_e=sqrt(e_downsample(:).^2-hilbert_e(:).^2); [pks,locs] = findpeaks(abs(h_e)); figure, plot(abs(h_e));
I will really appreciate, if anyone help me in cases 3 and 4.