Blind Image Watermarking Using WaveletCoefficient Distance

In this paper a robust digital image watermarkingalgorithm proposed in wavelet transform domain. At first, theoriginal image is decomposed into ten sub-bands by the 3-levelwavelet transform. Then, the values of wavelet coefficients inHL3 are quantized. For embedding watermark bits, trees ofwavelet coefficients are used. In each tree, the distance betweenthe average of four wavelet coefficients in HL2 and theircorresponding HL3 coefficient determines how HL3 coefficientis quantized. The experimental results show that the proposedalgorithm has a good resistance against to common attacks,especially JPEG compression; moreover it outperformsprevious methods in the most situations.

Keywords:

watermarking , wavelet transform , quantizationdistance