Image Hiding Based on a Hybrid Technique of VQ Compression and Discrete Wavelet Transformation

Abstract

Data hiding is to embed the important or secure information into a cover image and thus a stego-image is generated. By transferring the stego-image in public computer networks, the embedded information can be successfully transferred to the receiver. This paper proposes a hybrid technique of VQ compression and discrete wavelet transformation for image hiding. The proposed method compresses the gray-level secret image with VQ compression before the secret image is hidden. Before VQ encoding, a codebook is trained such that the quality of the secret image can be better in encryption and decryption. The compressed data of the gray-level secret image is encrypted and then embedded into the DWT coefficients of the cover image. After inverse DWT calculating, the stego-image is generated. Finally, the sender only needs to transfer the stego-image, two keys, and a set of the initial codewords to the receivers. The secret image can be rebuilt with the received information. If the stego-image is destroyed, the proposed method can also recover the secret image partially.