MPEG/audio Layer III 音樂壓縮格式是目前音樂工業中最新、最主要的技術。我們提出一個具有高精確度的硬體架構MP3解碼器。為了符合高精確度的要求，我們採用了24位元浮點數運算核心。我們利用Cadence Verilog-XL Simulator來模擬和驗證我們所提出的架構。模擬所得到的結果是一個個的PCM樣本，這些PCM樣本經由加入aiff檔頭後變成aiff檔案格式，可以被Windows Media Player或是Quick Time Player所播放。數位聲音壓縮技術使得聲音資料得以大大的降低儲存空間和傳輸率。不同的壓縮技術提供不同等級的壓縮複雜度、壓縮率和音質。MPEG/audio壓縮演算法是第一個具有高傳真的數位聲音壓縮國際標準。MPEG/audio編碼器利用人耳聽覺系統對於感知上的限制來壓縮數位聲音資料。只要是能被人耳所能聽得見的訊號都能用MPEG/audio來壓縮。MPEG/audio共可分為三個層級，每個相繼的層級同時也增進壓縮品質和壓縮複雜度。MP3是MPEG/audio壓縮標準中最受歡迎的，它良好的壓縮品質主要是因為把樣本從時間域轉換到頻率域。我們介紹MP3的資料格式以及整個MP3的解碼流程。MP3的解碼流程主要可以分成兩大部份：解碼封裝格式以及資料計算。解碼封裝格式主要是包含了定位聲音資料的起始位置，解side information、scalefactor、Huffman encoded data。資料計算部份主要是針對解碼封裝格式所解出來的資料做運算，經由一連串繁複的運算之後即可獲得PCM樣本。

The MPEG/audio Layer III audio compression is the new key technology of the music industry. We proposed a hardware architecture for high-precision MP3 audio decoding. In order to satisfy the accuracy requirement, a 24-bit floating-point computation core is proposed. The architecture has been simulated and verified using the Cadence Verilog-XL Simulator. The simulation results, PCM samples, can be added aiff header and played by Windows Media Player or Quick Time Player.

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