應用電腦產生人造樂器聲音之研究

On the Generation of Artificial Sounds by Computer

鄭嘉緯(Chia-Wei Cheng)

指導教授 ： 李家同

國立暨南國際大學/科技學院/資訊工程學系/碩士(2008年)

https://doi.org/10.6837/NCNU.2008.00265

摘要

早從幾千幾萬年前，音樂就在生活之中扮演著人們不可或缺的重要角色。每一首膾炙人口的經典樂章，更讓許多人深深的沈浸其中。而樂章是由許多個音符所組成，每個音符表示其音階及其演奏長度，但音階在電腦中又代表著什麼的呢？本篇將從電腦的角度出發，將聲音訊號轉換成為數位訊號並儲存在電腦之中，再利用傅立葉轉換後進行頻譜的分析，並比較各個樂器之間的相異之處。

除此之外，我們將試圖尋找出樂器聲音組成的基本範本，並依據此範本，透過反傅立葉轉換以電腦模擬產生任意音階，以便更進一步的達到以模擬之樂器演奏歌曲。在本篇論文中，我們已經模擬了數種樂器，並且透過電腦模擬該樂器演奏歌曲，就如同是一架可以彈奏多種樂器的電子琴一樣，而我們在實驗中得到了不錯的結果。

關鍵字

音階 ； 數位訊號 ； 樂器 ； 電腦 ； 傅立葉轉換 ； 反傅立葉轉換 ； 樂器模擬

並列摘要

Music has acts a very important role in people’s life for several million years. Many popular movements make much people crazy for it. The movements are represented by music scores, and the music scores are composed of music notes. Every music note represents a tone and its length. But what is the physical meaning of a music tone? Can we analyze it by using a computer? In this thesis, we talk about the physical meaning of music tones from the view of computer analysis after transforming analog signals into digital signals. We will use the Discrete Fourier Transform to analyze the spectrum of a music tone, and compare the tones between different instruments.

Beside, we try to find out the pattern of an instrument. According to the pattern we find out, we can simulate the sampling instrument and simulate any tones of the instrument after using Discrete Inverse Fourier Transform. Moreover, we play songs by these simulated instruments. We’ve already simulated many instruments in this thesis, and we also play songs by these simulated instruments on computer.

並列關鍵字

music notes ； digital signal ； Discrete Fourier Transform ； Discrete Inverse Fourier Transform ； instruments simulation ； computer

參考文獻

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