Image watermarking using data compression

In this paper we propose a new image watermarking technique using data compression. This technique consists at first step in getting the first color in case of RGB image and obtaining a two dimensional matrix. Then the 2-D lifting wavelet transform (LWT2) (Sema KAYHAN, Ergun ERçELEB, 2011), is applied to this two dimensional matrix or image in order to have four sub-images, cA1, cH 1, cV1 and cD 1. Then the Discrete Cosine Transform (DCT) is applied to cA1 and we insert the Watermark signal into the obtained DCT values. This Watermark signal is obtained after compression of the original signal which is a speech waveform. This compression is performed in the wavelet domain. After inserting the watermark signal, the inverse of DCT is applied in order to obtain the sub-image, cA11. The watermarked image is finally obtained by the application of the inverse of LWT2, ILWT2, to the four sub-images, cA11, cH 1, cV1 and cD 1. The extraction process is simply subtracting the original DCT coefficients from the watermarked sub-image (cA11) ones. After extracting the compressed signal, the latter is decompressed in order to recover the original signal. The proposed image watermarking technique is applied on a number of color images and a speech waveform is used in experiments. The obtained results from PSNR, MSE SSIM, SIM and SNR, show the performance of the proposed image watermarking technique.