Robust Image Watermarking Scheme Based on Wavelet Technique

In this paper, an image watermarking scheme based on multi bands wavelet transformationmethod is proposed. At first, the proposed scheme is tested on the spatial domain (for both a nonand semi blind techniques) in order to compare its results with a frequency domain. In thefrequency domain, an adaptive scheme is designed and implemented based on the bandsselection criteria to embed the watermark. These criteria depend on the number of waveletpasses. In this work three methods are developed to embed the watermark (one band(LL|HH|HL|LH), two bands (LL&HH | LL&HL | LL&LH | HL&LH | HL&HH | LH&HH) and threebands (LL&HL&LH | LL&HH&HL | LL&HH&LH | LH&HH&HL) selection. The analysis resultsindicate that the performance of the proposed watermarking scheme for the non-blind scheme ismuch better than semi-blind scheme in terms of similarity of extracted watermark, while thesecurity of semi-blind is relatively high. The results show that in frequency domain when thewatermark is added to the two bands (HL and LH) for No. of pass =3 led to good correlationbetween original and extracted watermark around (similarity = 99%), and leads to reconstructedimages of good objective quality (PSNR=24 dB) after JPEG compression attack (QF=25). Thedisadvantage of the scheme is the involvement of a large number of wavelet bands in theembedding process.