Binaural reproduction for headphone-based listening is an active research area due to its widespread use in evolving technologies such as augmented and virtual reality (AR and VR). On the one hand, these applications demand high quality spatial audio perception to preserve the sense of immersion. On the other hand, recording devices may only have a few microphones, leading to low-order representations such as first-order Ambisonics (FOA). However, first-order Ambisonics leads to limited externalization and spatial resolution. In this paper, a novel head-related transfer function (HRTF) preprocessing optimization loss is proposed, and is minimized using nonlinear programming. The new method, denoted iMagLS, involves the introduction of an interaural level difference (ILD) error term to the now widely used MagLS optimization loss for the lateral plane angles. Results indicate that the ILD error could be substantially reduced, while the HRTF magnitude error remains similar to that obtained with MagLS. These results could prove beneficial to the overall spatial quality of first-order Ambisonics, while other reproduction methods could also benefit from considering this modified loss.

翻译：双耳回放技术因其在增强现实和虚拟现实等新兴技术中的广泛应用而成为耳机听音领域的研究热点。一方面，这些应用需要高质量的空间音频感知以保持沉浸感；另一方面，录音设备可能仅配备少数麦克风，导致低阶表示形式如头一阶Ambisonics（FOA）的使用。然而，头一阶Ambisonics会导致外部化和空间分辨率受限。本文提出了一种新颖的头相关传递函数（HRTF）预处理优化损失函数，并通过非线性规划进行最小化。新方法命名为iMagLS，其在当前广泛使用的MagLS优化损失中引入侧平面角度的双耳水平差（ILD）误差项。结果表明：ILD误差可显著降低，同时HRTF幅度误差与MagLS结果保持相近。这些发现对提升头一阶Ambisonics的整体空间质量具有潜在价值，而其他回放方法也可通过考虑这种改进的损失函数获益。