Optimized Preprocessing for Spatially Robust Room Impulse Response Reshaping

Abstract:
The purpose of room impulse response reshaping is to reduce reverberation and thus to improve the perceived quality of the received signal by prefiltering the source signal before it is played back with a loudspeaker. The optimization of an infinity- and/or p-norm based objective function has proven to be quite effective compared to least-squares methods. Multi-position approaches have been developed in order to increase the robustness against small movements of the listener. The drawback, however, of the multi-position approach is the great amount of measurements that need to be done prior to equalizer design. A recent method considered the system perturbations in the case of small spatial mismatch and with arbitrary weighting for the reverberation tail. The drawback of this approach is the computation effort required to preprocess the data. In this paper we present a method to significantly speed up this preprocessing step. Index Terms — room impulse response, reshaping, robustness, optimization, p-norm.