摘要
针对通用小波失真函数(UNIWARD)的失真代价的四舍五入误差为1/2时嵌入失真为零的问题,基于边信息的通用小波失真函数(SI-UNIWARD),提出了一种改进隐写方案。该方案首先对前载体的原始像素值进行四舍五入,然后重新定义了一组间距合理的四舍五入误差,产生了新的嵌入代价,重新使用了在SI-UNIWARD中禁用的00、40、04、44模式中的1/2离散余弦变换(DCT)系数,避免了检测性能的病态饱和,从而解决了零嵌入失真代价问题。实验表明,该方案与SI-UNIWARD相比,DCT系数的更改概率降低了3%,同时降低了空域中像素值间的数量差别和DCT系数的嵌入更改率,提升了检测误差性能,能够较好地利用边信息。
To solve the problem of the distortion cost being zero when the rounding error of the distortion cost in UNIWARD is 1/2,a new steganography scheme based on SI-UNIWARD was proposed.At first,the raw pixels of the precover are rounded,then a set of rounded error which have reasonable distance are redefined,and new embedded costs are generated.Consequently,the DCT coefficients of the 00,40,04,44 modes which are prohibited in SI-UNIWARD are reused.Finally,the pathological behavior of the detection performance is avoided,and the zero-embedding-cost problem is solved.The experimental results show that compared with SI-UNIWARD,the probability of changed DCT coefficients,pixel difference in spatial domain and the changes in spatial domain caused by DCT embedding are lowered,detection performance are promoted,and the side information are better used.
出处
《计算机科学》
CSCD
北大核心
2016年第5期108-112,共5页
Computer Science
基金
国家自然科学基金(61379152)
国家自然科学青年基金资助项目(61403417)资助
关键词
通用小波失真函数
失真函数
图像隐写
自适应隐写
隐写分析
Universal wavelet relative distortion（UNIWARD）
Distortion function
Steganography
Adaptive steganography
Steganalysis
