基于方向编码的离散余弦变换域图像隐写算法

提出一种基于方向编码的离散余弦变换(DCT)域图像隐写算法。将秘密图像进行8×8块的离散余弦变换后，采用JPEG标准量化表进行量化，将得到的DCT系数做行程编码，间接提高嵌入容量。同时对载体图像进行8×8块的离散余弦变换，采用改进的量化表进行量化，由此提高嵌入容量和含密图像的质量。通过基于方向编码的嵌入算法将秘密信息嵌入载体图像DCT系数的中低频部分。实验结果证明，该隐写算法嵌入容量大，得到的含密图像视觉质量好，可抵抗 分析攻击。

Image Steganographic Algorithm Based on Direction Coding in Discrete Cosine Transform Domain

This paper proposes an image steganographic algorithm based on direction coding in Discrete Cosine Transform(DCT) domain.The secret image is transformed by 8 × 8 block DCT and quantized by using JPEG standard quantification table,then the DCT coefficients are coding by the trip coding.And the cover image is transformed by 8 × 8 block DCT and quantized by using the improved quantification table,which raises the embedding capacity indirectly.The secret image data are embedded in the low frequency of the cover image’s DCT coefficients by using the steganorgraphy algorithm based on direction coding.Experimental results prove that the steganorgraphic method has a great embedding capacity,makes the image containing secret image has a good visual effect,and it can resist to analysis.