Improved dynamic match phone lattice search using Viterbi scores and Jaro Winkler distance for keyword spotting system
Maria Rajabzadeh, Shima Tabibian, Ahmad Akbari, Babak Nasersharif · 2012
Keyword spotting (KWS) refers to finding of all occurrences of the chosen words in speech utterances. One of known methods for KWS problem is phone lattice search (PLS). In this method, accuracy and speed of lattice search are most important aspects. One method used in PLS, is Minimum Edit Distance (MED) measure. While this measure increases detection rate, it also raises the false alarm rate. In this paper, we propose some approaches to improve the false alarm rate and also the search speed. We use Viterbi scores and Jaro-Winkler distance besides MED measure in order to decrease the false alarm rate. We also use lattice pruning and indexing techniques for increasing the speed of search on the lattice. Results show that proposed method increases accuracy and search speed of KWS system in comparison to using only MED measure.