Integrated linear prediction residuals (ILPR) was an effective feature proposed by T V Ananthapadmanabha in 1995, which closely approximates the voice source signal.[1] This proved to be very effective in accurate estimation of the epochs or the glottal closure instant.[2] A G Ramakrishnan et al. showed in 2015 that the discrete cosine transform coefficients of the ILPR contains speaker information that supplements the mel frequency cepstral coefficients.[3] Plosion index is another scalar, time-domain feature that was introduced by T V Ananthapadmanabha et al. for characterizing the closure-burst transition of stop consonants.[4]