{'fraction_non_alphanumeric': 0.017664376840039256, 'fraction_numerical': 0.004906771344455349, 'mean_word_length': 5.415094339622642, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Subband nonstationary noise reduction based on multichannel spatial prediction under reverberant environments

We propose a novel non-stationary and convolutive noise reduction method under reverberant environments. Unlike many multichannel noise reduction methods, the proposed method does not need pre knowledge of impulse response or direction of arrival (DOA) of the target source. The proposed method is composed of two processes. On the noise reduction process, the noise component is reduced without the impulse response of the target source. The target source component in the output signal is distorted, but the distortion is removed by the distortion-restoration process. Importantly, possibility of complete noise reduction with no distortion based on the proposed framework is assured by MINT theory. Experimental results under the reverberant environment (RT60 ≈ 300 ms) show that the proposed method can reduce more noise than the conventional method and the distortion of the target source is not so big.