NDF+: Joint Neural Directional Filtering and Diffuse Sound Extraction
Abstract
Recently, neural directional filtering (NDF) has been introduced as a flexible approach for reconstructing a virtual directional microphone (VDM) with a desired directivity pattern for spatial sound capture. Building on this idea, we propose NDF+, which enables joint neural directional filtering and diffuse sound extraction. NDF+ reformulates VDM estimation into two coupled subtasks: dereverberated VDM reconstruction and diffuse sound extraction. This reformulation enables NDF+ to manipulate diffuse components in the final reconstructed VDM output. We evaluated NDF+ under reverberant conditions and compared it with representative conventional baselines. Results show that NDF+ consistently outperforms the baselines on both subtasks, while maintaining VDM reconstruction quality comparable to that of the original single-task NDF model. These findings indicate that NDF+ introduces an additional degree of freedom for diffuse sound control in the VDM reconstruction. In a stereo recording application, NDF+ provides controllable inter-channel level differences between left and right channels by adjusting the estimated diffuse component.
Keywords
Cite
@article{arxiv.2605.06108,
title = {NDF+: Joint Neural Directional Filtering and Diffuse Sound Extraction},
author = {Weilong Huang and Le Nhat Tam Huynh and Oliver Thiergart and Emanuël A. P. Habets},
journal= {arXiv preprint arXiv:2605.06108},
year = {2026}
}