本論文提出新穎低複雜度且彈性化心理聲學模型與搭配開發出來的以聽力圖為基礎有效率等化系統。所設計等化系統具有以下幾個特色: 1)透過心理聲學模型，人耳存在的遮蔽效應可以讓系統每音框需做等化的點數大幅下降約70%，且考慮應用上的不同，本論文在心理聲學模型設計省略不必要的步驟，以降低計算複雜度，跟原始模型比較可降低約30%~40%的運算且不影響音質，除此以外，本論文提出之模型不需要去全頻的計算心理聲學模型，彈性化的設計在應用上更可以減輕心理聲學模型對於系統帶來的負擔。2)考慮聽力圖為基礎的等化演算法，透過考慮人耳(正常人)存在的聽力損失，將這些損失當作等化的依據，讓等化器的效果更好，3) 因為心理聲學遮蔽效應特性，在計算上捨棄了冗餘的訊號，進而降低每個音框的輸出功率。以整體等化器系統來說，本論文提出符合人耳特性的架構設計，比較數據上擁有最低的運算量且不會遜色的音質，此外，更有最低的輸出功率，跟其他架構相比，更適合實現於可攜帶裝置上。

This paper presents a novel low complexity and flexible psychoacoustic model with proposed audiogram based efficient audio equalization system. Our proposed structure have the following characteristics: 1) With psychoacoustic model, we can reduce the processing points about 70% every frame according to the masking effect in our ears. Besides, based on different purpose, we keep only the necessary steps in psychoacoustic model which reducing 30%-40% operations without affecting the sound quality compared with original model in MPEG standard. Moreover, the flexible design with band-selectable strategy in our model lightening the burden on our system when we don’t need to calculate full-band model; 2) The equalization algorithm based on audiogram considering the hearing loss in normal people, we adjust the gain in frequency domain with the information given by audiogram making the equalization better and adaptive; 3) With the masking effect in psychoacoustic, the redundant signals were discarded, leading to the lower output power every frame. Compared with other audio equalizer with filter bank design, our proposed structure has the lowest computation complexity, lowest output power. Nevertheless, considering the property in human ear, our proposed is more suitable for normal using. Based on the above, the proposed structure would be a new solution for future application in audio processing.

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