关键词: 水印, 矢量量化, 人类视觉系统（HVS）, 扩频, 鲁棒性

Abstract: In this paper a novel Vector Quantization（VQ） and Discrete Cosine Transform（DCT） based adaptive multi-watermark algorithm was proposed.In proposed work，two different watermarks，which represent the owner of the product，were embedded into the codebook of the image and DCT domains according to Human Visual System（HVS） and image character.By means of adaptively selecting the embedding parameter，the imperceptibility and security on anti attack ability were guaranteed.Experimental results illustrate that the proposed technique provides an improvement over the spread spectrum watermarking technique in terms of robustness for various signal processing attacks，especially in resisting collusion attack.

Key words: watermark, Vector Quantization（VQ）, Human Visual System（HVS）, Spread Spectrum Technique（SST）, robustness