English  |  正體中文  |  简体中文  |  Items with full text/Total items : 90074/105197 (86%)
Visitors : 7153302      Online Users : 33
RC Version 6.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version

    Please use this identifier to cite or link to this item: http://asiair.asia.edu.tw/ir/handle/310904400/9616

    Title: 在語音增強系統中使用頻譜移動向量於音樂型殘留雜訊之壓抑研究
    Authors: 陸清達
    Contributors: 資訊學院
    Keywords: 語音增強;音樂型殘留雜訊;頻譜向量變化;殘留雜訊壓抑;雜訊干擾;speech enhancement;musical residual noise;spectral-bin motion;suppression of residual noise;noise corruption
    Date: 2008
    Issue Date: 2010-05-13 13:31:47 (UTC+8)
    Abstract: 大多數的語音增強系統處理完受到各種雜訊干擾的語音信號之後,都會產生音樂型殘留雜訊;而 該音樂型殘留雜訊是因增強處理之後,殘留的雜訊頻譜隨機的分佈於每個次頻帶,使得殘留雜訊聽起 非常吵雜。本研究計畫的目的:就是要分析受干擾語音信號被語音增強處理後的殘留雜訊特性,進而 設計壓抑殘留雜訊的後處理系統,降低音樂型殘留雜訊的影響。首先,我們必須先實現各種不同類型 的語音增強演算法,包括:頻域、小波域、信號子空間等的最新語音增強演算法;然後蒐集各種不同 類型語音增強系統所產生的殘留雜訊,予以分析、比較,詳細討論各種殘留雜訊特性。最後,我們將 嘗試提出語音增強的後處理系統,經由分析音樂型殘留雜訊在相鄰數個音框的頻譜變化軌跡,然後衡 量該軌跡的絮亂程度或連續變化程度,以評量出該頻譜軌跡屬於殘留雜訊或語音信號;如果是殘留雜 訊,我們將給予壓抑;反之,則為語音信號,我們將給予保留。此外,母音對中文語音品質,具有關 鍵性的影響,根據母音中的諧波頻譜在前後音框間變化較為穩定,而且相鄰頻帶間的頻譜相關性也很 高;我們將對某些次頻帶被語音增強系統刪除或被雜訊污染導致消失的諧波頻譜,予以重建以提升語 音信號的品質。

    Most speech enhancement systems suffer from musical residual noise when a system enhances a noisy speech signal corrupted by various kinds of colored noise. The musical residual noise sounds very annoying to the human ears, and is caused by the spectral peaks of residual noise that randomly appear over subbands of a frame and in successive frames. This project aims to reduce the effect of musical residual noise. In order to analyze the properties of residual noise in enhanced speech, we have to collect the residual noise data. Therefore, some novel speech enhancement algorithms should be implemented to achieve residual noise. The enhancement algorithms include spectral domain, wavelet domain and signal subspace et al. Hence, we try to design a post processing system to reduce the amount of residual noise for a speech enhancement system by analyzing the spectral variation contour of each subband in successive frames. The enhanced spectra are categorized as either speech dominant or noise dominant by analyzing the motion property for each frequency bin. In the case of noise-dominant spectral bin, this bin should be suppressed to reduce the residual noise. Conversely, this spectral bin is speech dominated and should be preserved to maintain speech quality. Moreover, the speech quality major depends on the vowel signal in an utterance for mandarin Chinese spoken language. We will also try to reconstruct the harmonics of a vowel signal based on the inter-frame spectral variation being smooth and the spectral correlation being high among the neighbors of a spectral bin. The improved speech quality can be obtained by reconstructing the harmonics which were removed by a speech enhancement system or destroyed by a corrupting noise.
    Appears in Collections:[資訊傳播學系] 科技部研究計畫

    Files in This Item:

    File Description SizeFormat
    97陸清達1.doc21KbMicrosoft Word443View/Open

    All items in ASIAIR are protected by copyright, with all rights reserved.

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback