Digital watermarking algorithm combining spread spectrum with image scrambling
Liao Ke-yu · Information technology newsletter · 2005
A spread spectrum digital image watermarking algorithm was proposed,in which Gold codes were applied to the structure design of watermark and image scrambling was used to scramble watermarking image.Image scrambling improved vision effect of watermarking image.By exploiting the characteristics that Gold codes have more independent codes,the binary image watermark was modulated with multibit binary information regarded as an unit,and then was adaptively embedded into low frequency components of the scrambling image in discrete cosine transform domain.The longer spread spectrum sequences could be used and the robustness accordingly is enhanced by utilizing the Gold codes.This scheme combining spread spectrum with(image) scrambling is more robust against various attacks,such as adding noise,filtering and lossy compression.