Use of articulatory bottle-neck features for query-by-example spoken term detection in low resource scenarios

For query-by-example spoken term detection (QbE-STD), generation of phone posteriorgrams requires labelled data which would be difficult for languages with low resources. One solution is to build models from rich resource languages and use them in the low resource scenario. However, phone classes are not language universal and alternate representation such as articulatory classes is explored. In this paper, we use articulatory information and their derivatives such as bottle-neck (BN) features (also referred to as articulatory BN features) for QbE-STD. We obtain Gaussian posteriorgrams of articulatory BN features in tandem with the acoustic parameters such as frequency domain linear prediction cepstral coefficients to perform the search. We compare the search performance of articulatory and phone BN features and show that articulatory BN features are a better representation. We also provide experimental results to show that low amounts (30 mins) of training data could be used to derive articulatory BN features.