雙耳聽覺演算法主要是用來增強耳機系統聲場的表現，其演算法主要由三個部分所組成1)空間分析(Spatial Analysis)、2)空間合成(Spatial synthesis)、3)雙耳合成(Binaural synthesis)，藉由經過這樣的處理得到增強聲場的雙耳音訊。但是在雙耳合成時，使用量測到的頭相關轉移函數(HRTFs)來重建耳機內聲源位置的資訊，會使得運算量以及儲存量非常的大，這對系統來說是非常大的負擔，故本論文提出一種低複雜度雙耳合成應用於雙耳聽覺演算法。本論文使用HRTFs的特性先將其轉換成最小相位濾波器以及一個雙耳時間差的延遲後，在將其最小相位部分使用共聲學極點與零點進行逼近，而最後使用Shuffler濾波器結構來減少渲染對稱聲源時所需要的濾波器組。其實驗顯示本論文所提出的雙耳合成演算法與原始演算法相比其儲存需求量節省了86.25%，而在運算資源上乘法運算量節省了86.25%、加法運算量則節省了83.88%，最後則使用PEAQ進行客觀音質分析，透過這個參數的評估及分析後可知，本論文所提出的雙耳合成架構之效果，能夠和使用量測得到的HRTFs得到相同的效果。

The Binaural auralization algorithm is used to enhance the performance of the sound field in headphone system. This algorithm is involve three parts: 1)Spatial analysis; 2)Spatial synthesis; 3)Binaural synthesis. By this processing, a binaural audio signal with an enhanced sound field is obtained. However the computational cost and memory usage of measured HRTF are so huge that make synthesize 3D audio arduously in real-time. In this thesis, we proposed a low-complexity and low memory usage binaural synthesis architecture for binaural auralization algorithm to overcome this problem.
Frist, we represent HRTFs with a pure delay followed by minimum-phase system. Then the minimum phase HRTF is used to estimate the common acoustical pole and direction-dependent zeros for modeling IIR filter. Finally, for a symmetrical acoustical system, the Shuffler filter architecture can be used to reduce computation cost.The experiment shows that the binaural synthesis framework presented in this thesis has 86.25% saving in memory usage, and 85% saving in computational cost compared to the original framework. And, using PEAQ methods to analyze the objective sound quality, through the evaluation and analysis of the parameter, we can see that the effect of propoesd in this thesis is the same as measured HRTFs.

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