The 4.0 kbit/s speech codec described in this paper is based on a Frequency Domain Interpolative (FDI) coding technique, which belongs to the class of prototype waveform Interpolation (PWI) coding techniques. The codec also has an integrated voice activity detector (VAD) and a noise reduction capability. The input signal is subjected to LPC analysis and the prediction residual is separated into a slowly evolving waveform (SEW) and a rapidly evolving waveform (REW) components. The SEW magnitude component is quantized using a hierarchical predictive vector quantization approach. The REW magnitude is quantized using a gain and a sub-band based shape. SEW and REW phases are derived at the decoder using a phase model, based on a transmitted measure of voice periodicity. The spectral (LSP) parameters are quantized using a combination of scalar and vector quantizers. The 4.0 kbits/s coder has an algorithmic delay of 60 ms and an estimated floating point complexity of 21.5 MIPS. The performance of this coder has been evaluated using in-house MOS tests under various conditions such as background noise. channel errors, self-tandem. and DTX mode of operation, and has been shown to be statistically equivalent to ITU-T (3.729 8 kbps codec across all conditions tested.
標簽: frequency-domain interpolation performance Design kbit_s speech coder based and of
上傳時間: 2018-04-08
上傳用戶:kilohorse
css美化有序列表,貼出部分css代碼 <ol > <li>先涂粉底再涂防曬</li> <li>先涂防曬再涂粉底</li> </ol> <!doctype html> <html> <head> <title>CSS3 ordered list styles - demo</title> <style> body{ margin: 40px auto; width: 500px; } /* -------------------------------------- */ ol{ counter-reset: li; list-style: none; *list-style: decimal; font: 15px 'trebuchet MS', 'lucida sans'; padding: 0; margin-bottom: 4em; text-shadow: 0 1px 0 rgba(255,255,255,.5); } ol ol{ margin: 0 0 0 2em; } /* -------------------------------------- */
上傳時間: 2018-08-22
上傳用戶:53660542
projcet2007模板內容豐富,項目計劃的編輯習慣,界面布局,時間計算的規則,任務的依賴關系等都和MS Project非常接近,用戶會用MS Project,就會用我們的計劃編輯功能。
上傳時間: 2019-02-19
上傳用戶:自由自在xc
關于晶習預測,各種立場優化與結構文件的優化與分析
標簽: 軟件教學 幫助掌握軟件的操作與運行!!!!!!!!!!!!!
上傳時間: 2019-04-23
上傳用戶:caicai123
MS8XF系列單片機常見問題解決辦法,仿真器常見問題 ,燒錄器及燒錄器軟件常見問題 等
標簽: MS 常見問題
上傳時間: 2019-06-11
上傳用戶:jdz8888
%========================開始提取加噪信號的各類特征值================================ for n=1:1:50; m=n*Ns; x=(n-1)*Ns; for i=x+1:m; %提取加噪信號'signal_with_noise=y+noise'的前256個元素,抽取50次 y0(i)=signal_with_noise(i); end Y=fft(y0); %對調制信號進行快速傅里葉算法(離散) y1=hilbert(y0) ; %調制信號實部的解析式 factor=0; %開始求零中心歸一化瞬時幅度譜密度的最大值gamma_max for i=x+1:m; factor=factor+y0(i); end ms=factor/(m-x); an_i=y0./ms; acn_i=an_i-1; end gamma_max=max(fft(acn_i.*acn_i))/Ns
上傳時間: 2020-04-07
上傳用戶:如拷貝般復制
%========================開始提取加噪信號的各類特征值================================ for n=1:1:50; m=n*Ns; x=(n-1)*Ns; for i=x+1:m; %提取加噪信號'signal_with_noise=y+noise'的前256個元素,抽取50次 y0(i)=signal_with_noise(i); end Y=fft(y0); %對調制信號進行快速傅里葉算法(離散) y1=hilbert(y0) ; %調制信號實部的解析式 factor=0; %開始求零中心歸一化瞬時幅度譜密度的最大值gamma_max for i=x+1:m; factor=factor+y0(i); end ms=factor/(m-x); an_i=y0./ms; acn_i=an_i-1; end gamma_max=max(fft(acn_i.*acn_i))/Ns
上傳時間: 2020-04-07
上傳用戶:如拷貝般復制
The General Packet Radio Service (GPRS) allows an end user to send and receive data in packet transfer mode within a public land mobile network (PLMN) without using a permanent connection between the mobile station (MS) and the external network during data transfer. This way, GPRS opti- mizes the use of network and radio resources (RRs) since, unlike circuit- switched mode, no connection between the MS and the external network is established when there is no data flow in progress. Thus, this RR optimiza- tion makes it possible for the operator to offer more attractive fees.
上傳時間: 2020-05-27
上傳用戶:shancjb
接觸Silvaco TCAD仿真軟件已經有很長時間了,這期間還熟悉了一下ISE TCAD。學習的過程中,老師、師兄姐和同學給了我極大的幫助。這本書的主旨就是希望提供一些對于Silvaco仿真的可資借鑒的經驗。學習和使用Silvaco的時候各人的視角會不一樣,雖然這本書只是介紹一些常用的仿真,例句也有限,但因為流程控制和語法都有相通的地方,完全可以參照本書和手冊的說明靈活地建立仿真以及仿真一些本書未提及的特性。寫本書的另一個動力是想體驗一下IAT在排版書籍上和word的不同。經過這次編排覺得各有優缺點。IZTX對排圖片和表格這些浮動元素很費力。我在排此書的時候經常遇到圖片和表格按照自動方式排的位置很差,和文字內容脫節很遠,為此不得不處理圖片,有時還將表格拆開等。如果各位遇到很脫節的地方還請見諒。LTX的使用需要有很強的耐心和探索精神,也可以說是犧牲精神。不管是MS Office還是ITEX,總的目的是想內容通順,閱讀起來舒服,用什么工具就是“八仙過海,各顯神通”了。
上傳時間: 2021-11-27
上傳用戶:qingfengchizhu
MSxxxxE系列交流伺服驅動器操作手冊,PLC自動化控制者適用
標簽: 電機驅動器
上傳時間: 2022-01-09
上傳用戶:XuVshu