Abstract. A high-fidelity reversible data hiding (RDH) algorithm using a discrete cosine transform (DCT) coefficients energy analysis-based predictor and optimized embedding is proposed. The algorithm utilizes the characteristic of energy distribution of natural image DCT coefficients to predict pixel values, which improves the prediction accuracy over conventional methods. Moreover, the algorithm establishes a pure load-image distortion function, which can be used to find optimized pixel expansion direction, secret message embedding location, and pixel sorting/selection threshold in each round of the multipass embedding process. Thus, the algorithm can better balance both image quality and data hiding capacity. Experimental results show that for high-fidelity RDH applications, comparing with several classical methods, the proposed algorithm always produces a high quality stego image in the same embedding capacity.

High-fidelity reversible data hiding using discrete cosine transform coefficients energy analysis-based predictor and optimized embedding

Now-a-days many unauthorized users try to get the protected information and therefore it is necessary to secure our data. Besides, there are also scenarios that data hiding needs to be done in the encrypted domain or combined with the encryption, especially in the age of big data and cloud computing. In previous method first encryption was done and then the room was vacated to hide the data. But there were some errors in data extraction and image recovery. In this paper a novel technique is proposed termed as reversible data hiding (RDH) by which we can hide our data. RDH is applied to encrypted images by which we can properly recover our data and the cover image. The hidden data can be in the form of text or image. In the proposed method we first vacate room to hide data and after encrypting image using certain encryption key the data hider reversibly hides the data whether text or image using data hiding key. In previous method only text was hidden. But the proposed paper is extended to hide the image also in the same reserved space which was used to hide text. The hidden image is also recovered without any errors. The results given in the paper proves that we can exactly recover the hidden data, hidden image and the cover image as and when needed by the receiver. The traditional RDH algorithm used is histogram shifting. By this method we can properly recover hidden data and cover image without any errors. Large amount of data can be hidden as compared to previous method.

P.S. Mahajani

Papers

Reversible Data Hiding in Cloud Based Applications