An implementation of steganography using construction of Huffman tree

We propose an implementation of steganography embedding secret information without degradation of the data quality or increase of data size using Huffman coding. When general digital data are compressed using Huffman coding, the alphabet and the symbol frequency of the source depend on the data. In many cases, the statistics of the data are investigated and code table optimized for the data is constructed and then, encoding is applied with the code table and encoded data are stored together with the coding table. In this paper, we propose an implementation of embedding data using degrees of freedom in Huffman coding. Any digital data can be used as cover data and the quality of data is completely preserved because the compression is lossless. The proposed method contributes to the expansion of the application of steganography and to the improvement of security of digital data.