Hybridization DE with K-means for speaker clustering in speaker diarization of broadcasts news

In this paper, we address the problem of optimal non-hierarchical clustering in the speaker clustering phase for the speaker diarization task of news broadcasts. A new hybridization combining differential evolution (DE) algorithm and K-means algorithm is proposed and tested on TV news database (TVND). To optimize the classification of speakers, two criteria, namely trace within criterion (TRW) and variance ratio criterion (VRC), were used as clustering validity indices, correcting every possible grouping of speakers’ segments. Concerning the encoding of the classification of clusters to be optimized, it is performed by the cluster centers in DE algorithm. Therefore, a problem of rearrangement of centers in the populations can be generated, which cannot ensure an efficient search by applying evolutionary operators. For this purpose, an efficient heuristic was also proposed for this rearrangement. Non-hybrid DE variants were applied with and without the rearrangement of cluster centers, and compared with the corresponding hybrid K-means variants. The experimental results have showed the high-efficiency of hybrid K-means variants with the rearrangement of cluster centers compared with those without the rearrangement of cluster centers and non-hybrid DE variants. Also, the obtained results using hybrid and non-hybrid DE variants with the rearrangement of cluster centers were quite similar using both TWR and VRC criteria. Moreover, the best efficiency was acquired using hybrid DE variants thanks to these two criteria from which a value of 13.05% of DER has been reached by hybrid b6e6rl variant.