Variance-Covariance Regularization for Improved End-to-End Diarization

End-to-end neural diarization (EEND) methods use just a single neural network. EEND-TA, a recently proposed EEND technique, performs diarization for a flexible number of speakers in a non-autoregressive manner. In this paper, we explore combining EEND-TA with Variance-Covariance Regularization (VCReg) to enhance representation learning. VCReg is designed to promote features with high variance and low covariance. We test several representations from EEND-TA for calculating VCReg loss, including Conversational Summary Vectors (CSVs), outputs from the last Conformer layer, attractor representations, and other intermediate outputs from the Conformer encoder. Our experiments on public datasets show notable improvements over the baseline. Additionally, the proposed method improves the performance over all datasets in our setup, showcasing the generalizability of this approach.