This book discusses the contribution of excitation source information in
discriminating language. The authors focus on the excitation source
component of speech for enhancement of language identification (LID)
performance. Language specific features are extracted using two
different modes: (i) Implicit processing of linear prediction (LP)
residual and (ii) Explicit parameterization of linear prediction
residual. The book discusses how in implicit processing approach,
excitation source features are derived from LP residual, Hilbert
envelope (magnitude) of LP residual and Phase of LP residual; and in
explicit parameterization approach, LP residual signal is processed in
spectral domain to extract the relevant language specific features. The
authors further extract source features from these modes, which are
combined for enhancing the performance of LID systems. The proposed
excitation source features are also investigated for LID in background
noisy environments. Each chapter of this book provides the motivation
for exploring the specific feature for LID task, and subsequently
discuss the methods to extract those features and finally suggest
appropriate models to capture the language specific knowledge from the
proposed features. Finally, the book discuss about various combinations
of spectral and source features, and the desired models to enhance the
performance of LID systems.