This paper introduces a novel (HDAG - Harmonic Detection for Auditory Gain) method for speech intelligibility enhancement in noisy scenarios. In the proposed scheme, a series of selective Gammachirp filters are adopted to emphasize the harmonic components of speech reducing the masking effects of acoustic noises. The fundamental frequency are estimated by the HHT-Amp technique. Harmonic patterns estimated with low accuracy are detected and adjusted according the FSFFE low/high pitch separation. The central frequencies of the filterbank are defined considering the third octave subbands which are best suited to cover the regions most relevant to intelligibility. Before signal reconstruction, the gammachirp filtered components are amplified by gain factors regulated by FSFFE classification. The proposed HDAG solution and three baseline techniques are examined considering six background noises with four signal-to-noise ratios. Three objective measures are adopted for the evaluation of speech intelligibility and quality. Several experiments are conducted to demonstrate that the proposed scheme achieves better speech intelligibility improvement when compared to the competing approaches. A perceptual listening test is further considered and corroborates with the objective results.

翻译：本文提出了一种新颖的谐波检测听觉增益方法，用于在噪声环境下增强语音可懂度。在该方案中，采用一系列选择性Gammachirp滤波器来强调语音的谐波分量，从而降低声学噪声的掩蔽效应。基频通过HHT-Amp技术进行估计。针对低精度估计的谐波模式，根据FSFFE低/高频区分进行检测与调整。滤波器组的中心频率依据与可懂度最相关的三分之一倍频程子带来确定。在信号重建前，经过Gammachirp滤波的分量由FSFFE分类调控的增益因子进行放大。我们考察了所提出的HDAG方案及三种基线技术在六种背景噪声和四种信噪比下的表现，采用三种客观指标评估语音可懂度和质量。多项实验表明，与对比方法相比，所提方案能实现更优的语音可懂度提升。进一步开展的听觉主观听感测试结果与客观评价结果一致。