Environment-aware Listener-Optimized Binaural Enhancement of Speech (E-LOBES)

60岁以上的英国人口中，有一半以上与年龄有关的听力损失受到影响。听力损失使沟通变得困难，从而对生活质量产生严重的负面影响。轻至中度听力损失最常见的治疗方法是使用助听器。然而，即使有了助听器，听力受损的听众在嘈杂环境中理解语言的能力也更差，因为他们的听觉系统不太擅长区分想要的语言和不想要的噪音。一种解决方案是使用语音增强算法来选择性地放大期望的语音信号，同时衰减不需要的背景噪声。众所周知，正常听力听者在用两只耳朵听而不是只用一只耳朵听时，可以在噪声中更好地理解语音。两只耳朵上的信号之间的差异允许根据语音和噪声的空间位置来分离语音和噪声，从而提高了可理解性。现在，技术进步使两种助听器的使用成为可能，这两种助听器能够通过无线链路共享信息。通过以这种方式共享信息，助听器内的语音增强算法可以更准确地定位声源，并且通过联合处理用于两只耳朵的信号来确保保留声学信号中存在的空间线索。该项目的目标是通过开发联合增强双耳接收的语音的语音增强算法来利用这些双耳优势。大多数当前的语音增强技术是从电信行业发展而来的，并且被设计为仅作用于单耳信号。许多技术可以改善已经可以理解的语音的感知质量，但二进制掩蔽是少数几种已经被证明可以改善正常和听力受损的听者的噪声语音的可理解性的技术之一。在二进制掩蔽方法中，时频域中包含大量语音能量的区域保持不变，而包含少量语音能量的区域被抑制。在这个项目中，我们将扩展现有的单耳二进制掩蔽技术，以提供双耳语音增强，同时保留对于声源空间分离至关重要的耳间时间和级别差异。为了训练和调整我们的双耳语音增强算法，我们还将在项目中开发一种可懂度度量，该度量能够在存在竞争噪声源的情况下预测听力正常或受损的双耳收听者的语音信号的可理解性。该度量是在特定环境中自动找到单个听者的助听器的最佳设置的关键。双耳增强算法的最终评估和开发评估了一组听力受损的听者在噪声中的语音感知，这些听者也将被要求评估增强的语音信号的质量。

Age-related hearing loss affects over half the UK population aged over 60. Hearing loss makes communication difficult and so has severe negative consequences for quality of life. The most common treatment for mild-to-moderate hearing loss is the use of hearing aids. However even with aids, hearing impaired listeners are worse at understanding speech in noisy environments because their auditory system is less good at separating wanted speech from unwanted noise. One solution for this is to use speech enhancement algorithms to amplify the desired speech signals selectively while attenuating the unwanted background noise.It is well known that normal hearing listeners can better understand speech in noise when listening with two ears rather than with only one. Differences between the signals at the two ears allow the speech and noise to be separated based on their spatial locations resulting in improved intelligibility. Technological advances now make feasible the use of two hearing aids that are able to share information via a wireless link. By sharing information in this way, it becomes possible for the speech enhancement algorithms within the hearing aids to localize sound sources more accurately and, by jointly processing the signals for both ears, to ensure that the spatial cues that are present in the acoustic signals are retained. It is the goal of this project to exploit these binaural advantages by developing speech enhancement algorithms that jointly enhance the speech received by the two ears.Most current speech enhancement techniques have evolved from the telecommunications industry and are designed to act only on monaural signals. Many of the techniques can improve the perceived quality of already intelligible speech but binary masking is one of the few techniques that has been shown to improve the intelligibility of noisy speech for both normal and hearing impaired listeners. In the binary masking approach regions of the time-frequency domain that contain significant speech energy are left unchanged while regions that contain little speech energy are muted. In this project we will extend existing monaural binary masking techniques to provide binaural speech enhancement while preserving the inter-aural time and level differences that are critical for the spatial separation of sound sources.To train and tune our binaural speech enhancement algorithm we will also develop within the project an intelligibility metric that is able to predict the intelligibility of a speech signal for a binaural listener with normal or impaired hearing in the presence of competing noise sources. This metric is the key to finding automatically the optimum settings an individual listener's hearing aids in a particular environment.The final evaluation and development of the binaural enhancement algorithm assess speech perception in noise in a panel of hearing-impaired listeners who will also be asked to assess the quality of the enhanced speech signals.