A robust watermarking technique is implemented for copyright protection. The proposed method is based on 2-level discrete wavelet transform (DWT). The embedded watermarking information is a mobile phone number including the international code. The first level of the DWT transformation is applied on 16×16 blocks of the host image. All the coefficients of the 8×8 low-low (LL1) first level sub-band are grouped into one matrix. The second level of the DWT is then applied to the grouped matrix from the first level transformation. The highest coefficient from the LL2 sub-band (4×4) is used for embedding the watermark information. The extracting process is blind since it does not require the original image at the receiver side. The distortion in the host image due to the watermarking process is minimal and the PSNR is greater than 60 dB. The proposed algorithm showed robustness against several attacks such as scaling, filtering, cropping, additive noise and JPEG compression.
[1]
Xiang-Gen Xia,et al.
A multiresolution watermark for digital images
,
1997,
Proceedings of International Conference on Image Processing.
[2]
G. R. Sinha,et al.
Image Watermarking Using 3-Level Discrete Wavelet Transform (DWT)
,
2012
.
[3]
Ton Kalker,et al.
Reversible Image Watermarking Based on Integer-to-Integer Wavelet Transform
,
2007,
IEEE Transactions on Information Forensics and Security.
[4]
R. Qahwaji,et al.
A novel blind image watermarking technique for colour RGB images in the DCT domain using green channel
,
2008,
2008 Mosharaka International Conference on Communications, Computers and Applications.