本文選題：G.726標準 + ADPCM�。� 參考：《華中科技大學》2014年碩士論文

【摘要】：隨著通信和移動互聯網的發(fā)展，語音編碼的發(fā)展速度越來越快，國際電信聯盟也在不斷的更新編碼方案，G.726是國際電信聯盟建議的一種波形編碼方式，其特點是編碼語音質量高，延時短，穩(wěn)定性好。G.726是基于ADPCM(自適應差分脈沖編碼調制)算法的，將標準的G.711輸出信號進行再壓縮。G.726是一種非常有效的語音波形編碼方案，本文就旨在設計一個G.726編碼系統(tǒng)，實現語音的采集、編解碼、播放、存儲、傳輸等功能。 本文重點研究建議中的各個算法模塊在DSP上的實現。該設計將編碼算法從整體上劃分為自適應量化和自適應預測兩個模塊：在自適應量化模塊中，，分別實現了輸入PCM格式轉換、差分信號計算、量化定標因子自適應、自適應速度控制、單音信號和轉移（瞬變）檢測以及自適應量化6個子算法；在自適應預測模塊中，實現了反向自適應量化、自適應預測和重建信號子算法。文中詳細敘述了算法的硬件實現方案，并從成本，可靠性上都做了考慮，力爭朝產品化和商業(yè)化上發(fā)展。本文嚴格遵循ITUG.726標準，按照標準的建議用MATLAB驗證了每一編碼模塊，并創(chuàng)新地對算法進行了優(yōu)化，滿足編碼算法MOS得分，算法驗證符合要求后將其移植到DSP系統(tǒng)中，同時在一個系統(tǒng)中實現多種速率編碼，很好的完成了一個G.726編碼系統(tǒng)。
[Abstract]:With the development of communication and mobile Internet, speech coding is developing more and more rapidly, and the International Telecommunication Union (ITU) is constantly updating its coding scheme (G.726), which is a waveform coding method recommended by the International Telecommunication Union (ITU), which is characterized by the high quality of encoded speech. The delay is short, the stability is good. G. 726 is based on ADPCM (Adaptive differential Pulse Code Modulation) algorithm. Recompressing the standard G.711 output signal. G. 726 is a very effective speech waveform coding scheme. The purpose of this paper is to design a G.726 coding system. Achieve voice acquisition, codec, play, storage, transmission and other functions. This paper focuses on the implementation of the proposed algorithm modules on DSP. In this design, the coding algorithm is divided into two modules: adaptive quantization and adaptive prediction. In the adaptive quantization module, the input PCM format conversion, the difference signal calculation, the quantization scaling factor adaptation are realized, respectively. Adaptive speed control, single tone signal and transfer (transient) detection and adaptive quantization are 6 subalgorithms. In the adaptive prediction module, reverse adaptive quantization, adaptive prediction and reconstruction signal subalgorithms are implemented. In this paper, the hardware implementation scheme of the algorithm is described in detail, and the cost and reliability are considered in order to develop towards production and commercialization. According to the standard ITUG.726, this paper verifies every coding module with MATLAB, and innovatively optimizes the algorithm to satisfy the MOS score of the coding algorithm. The algorithm is transplanted to DSP system after the verification of the algorithm meets the requirements. At the same time, in a system to achieve a variety of rate coding, a good completion of a G.726 coding system.
【學位授予單位】：華中科技大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TN912.3

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本文編號：2091990