應用串接方法於連續變化轉速之四行程引擎聲音合成

Concatenation-based Method for the Synthesis of Engine Noise with Continuously Varying Speed

在本研究中，我們提出並實做一個串接式聲音合成系統，合成的標的物件是連續變化轉速之引擎聲音。我們提供一個繪圖的介面讓使用者畫出連續變化的引擎轉速曲線作為系統的輸入，然後輸出對應的引擎噪音。採用繪圖的方式，不僅能讓輸入更有彈性，也能減少輸入所需要的時間。主觀測試的實驗結果顯示，合成出來的聲音在自然度的測試上以及和原始引擎聲的相似度比較上有良好的表現。本論文所提出的方法，可以推廣到其他物理產生過程機制清楚簡單的聲音物件。此外，也可以應用到虛擬實境訓練或遊戲等等。

In this study, we propose and implement a concatenation-based audio signal synthesis system for the engine noises of continuously varying speed. A user simply draws the engine speed curve through an interface, and the corresponding audio signal is synthesized as output. This drawable interface makes the input function flexible and reduces the input time. The implemented system was evaluated with subjective tests. Overall, the performance was good regarding quality and similarity. The proposed method can be feasibly applied to the synthesis of any sound objects which are produced with a clear and simple physical process. Furthermore, the technology can be integrated to virtual reality, such as in training and gaming applications.