資料隱藏技術通常是不可回復的而且在資料隱藏後會導致原始資料會有輕微的破壞。雖然這些破壞是輕微的，但是在某些應用上是不被允許的，例如:軍事、醫學用途和必須維持原始品質的多媒體。
我們使用一個有高容量的可回復影像資訊隱藏演算法可用在彩色影像。我們利用數位影像中的冗餘來達到高資訊隱藏容量，而且只產生微小的失真(此失真為可回復的)。這個演算法在取出隱藏的資訊後也可以回復當初未藏入資訊的原始影像。我們也提出一個方法能夠在頻率域隱藏資訊。在實作上，小波轉換是會失真的，因為在計算小波轉換時，係數是實數，又在電腦中只有有限位數來處理實數，所以我們利用整數小波轉換來產生整數的係數。

Data hiding is usually irreversible and causes slight degradation in the cover image after embedding data. In some applications, such as military, medical and etc., they are desired to extract the embedded secret message and to restore original image.
We present a high capacity reversible data embedding technique based on difference modification. We explore the redundancy in each color component respectively. We can also adopt the cross-color embedding after data embedding in each color component. Our method can identify the embedding locations without using the location map to increase the payload size.

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