结合人眼对比度敏感视觉特性和图像特征,提出一种基于人眼视觉特性的频谱图的不同频率下最小可觉察误差阈值的计算方法,利用阈值来决定水印的嵌入和提取,设计水印方案并通过实验进行验证和攻击测试.结果表明,在JPEG压缩质量因子大于30%时,峰值信噪比均大于30 dB,隐蔽性较好;相似度在压缩质量因子为20%的情况下还能达到0.653 9,且从直观上看,提取的水印仍能清晰可见.%Based on the contrast sensitivity characteristics of human vision system and image features, a method was proposed to calculate the just noticeable difference thresholds of different frequencies of spectrum image.The thresholds was utilized to determine the watermark embedding and extraction.The watermarking scheme was designed, validated by experiment, and tested by attack, the results show that the peak signal noise ratio are all larger than 30 dB when JPEG compression quality factor is bigger than 30％, which indicates that the watermarks are well concealed.Normalized correlation value could still get to 0.6539 under the case of compression quality factor of 20 ％, and the extracted watermarks could still clearly be seen intuitively.
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