关键词: 版权水印, 认证水印, 自适应量化, 整数提升小波变换

Abstract: Due to the majority watermark algorithms have the sole function，this paper presents a novel multi-purpose digital watermark algorithm.At first，the image is transformed with the integer lifting wavelet，the coefficients of low frequency and the coefficient of horizontal high frequency are quantified using different quantitative formulas，which adjust to different embedding algorithm.Then，the robust watermark is embedded in the coefficients of low frequency to protect copyright；the original image content is hold，so it does not affect the second watermark embedding and extracting.The semi-fragile watermark is embedded in the coefficient of horizontal high frequency based on coefficient dither modulation to achieve the goal of content authentication.The experimental result shows this algorithm can realize copyright protection，tamper detection and localization well.

Key words: copyright watermark, authentication watermark, adaptive quantization, the integer lifting wavelet transformation