Bai Mingsian R, Chen Yi Wen, Hsu Yi-Cheng, Wu Tsung Yu
Department of Power Mechanical Engineering, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan.
J Acoust Soc Am. 2019 Aug;146(2):1302. doi: 10.1121/1.5123167.
In this paper, a robust binaural audio rendering system is proposed on the basis of a time-domain underdetermined multichannel inverse filtering approach. The celebrated multiple-input/output inverse theorem is reformulated into a general multichannel model-matching problem with the emphasis on binaural audio reproduction. Robustness with widened sweet spots is achieved by selecting multiple control points in the reproduction zones. The model-matching problem is formulated in the time domain as an underdetermined system, where the number of channels is selected in relation to the number of virtual sources and control points. Under the full-rank condition, exact solutions of inverse filters always exist to fulfill the ideal model-matching criterion. However, the gains of prefilters need to be limited in the design stage by using the Tikhonov regularization at a minor expense of matching performance. The proposed binaural audio system has been implemented on a six-element linear loudspeaker array. Three problems of binaural rendering, cross talk cancellation, source widening, and 5.1 virtual surround, are adopted to validate the proposed approach. Results of objective and subjective tests have demonstrated the efficacy of the proposed approach for binaural audio rendering.
本文基于时域欠定多通道逆滤波方法，提出了一种稳健的双耳音频渲染系统。著名的多输入/输出逆定理被重新表述为一个通用的多通道模型匹配问题，重点在于双耳音频再现。通过在再现区域选择多个控制点，实现了具有更宽最佳聆听区域的稳健性。模型匹配问题在时域中被表述为一个欠定系统，其中通道数量根据虚拟源和控制点的数量来选择。在满秩条件下，总是存在逆滤波器的精确解以满足理想的模型匹配标准。然而，在设计阶段需要通过使用蒂霍诺夫正则化来限制前置滤波器的增益，这会略微牺牲匹配性能。所提出的双耳音频系统已在一个六元线性扬声器阵列上实现。采用双耳渲染、串扰消除、声源扩展和5.1虚拟环绕这三个双耳渲染问题来验证所提出的方法。客观测试和主观测试的结果证明了所提出的双耳音频渲染方法的有效性。
