Using time-synchronous phone co-occurrences in a SVM-phonotactic dialect recognition system
Amparo Varona, Mikel Peñagarikano, Luis Javier Rodríguez-Fuentes, Germán Bordel, Mireia Díez · 2012
This paper presents a simple approach to phonotactic dialect recognition which uses lattices of time-synchronous phone co-occurrences at the frame level. In previous works, we success-fully applied cross-decoder phone co-occurrences to improve performance in language recognition experiments on the 2007 NIST LRE database. We call phone co-occurrence to the si-multaneous (time-synchronous) presence of two phone units coming from two different phone decoders. In this work, the approach is ported to a Dialect Recognition task based on the assumption that co-occurrences can better represent the tiny differences among the dialects. Besides, a slightly different approach is presented, based on the simultaneous presence of two phone units in the lattice produced by a single decoder (intra-decoder phone co-occurrences). For evaluating the ap-proach, a choice of open software (Brno University of Technol-ogy phone decoders, HTK, SRILM, LIBLINEAR and FoCal) was used, and experiments were carried out on the Arabic di-alects of the NIST 2011 LRE database. The approach based on cross-decoder phone co-occurrences outperformed the base-line phonotactic system, yielding around 8 % relative improve-ment. The fusion of both systems yielded 7.31 % EER and CLLR = 0.497, meaning 19 % relative improvement.