AAC在目前所有的音訊標準中提供了幾乎最好的品質在壓縮率及音質上。然而AAC編碼器的複雜度也遠比其他音訊標準來的要複雜許多，尤其是其中的位元分配部分，在兩個階層迴圈上需要執行大量的迴圈及運算時間。在這篇論文中，我們採用了知名的FAAC編碼器中的損益計算，而去預測量化刻度等級，從而進一步發展一個新的簡化整個外部迴圈的流程與計算的位元分配架構，此新的架構可將整個迴圈部分自原本的架構中排除，但其在數學運算上並不複雜。
相較於原始的FAAC，在時間上，原本雜訊計算部分的函式可以簡省了將近85%的時間，而對整個編碼系統來說，可以節省到25%的時間，而仍然維持住音值。在運算量上，新的方法需要由於不需要做迴圈，也有很大程度的減少。

AAC provides the highest quality and compression rate among all of the audio coding standards. However, AAC encoder’s complexity is higher than any other. Particularly in the bit allocation module. Two level loop’s part needs to do a lot of loops and operation time. In the thesis, we study the famous FAAC encoder’s calculation of distortion and try to predict quantize step size. Proposed a new and simply mathematical bit allocation module without outer iteration loop.
Comparing to the original FAAC, our new methods saves 85% encoding time in FixNoise function and 25% in whole encoder, but still maintains the quality. According to removing the loops, the new method dramatically reduce the amount of operations.

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