JPEG2000 Steganography Apparatus for minimizing the changes of code-block noise variances and methode threrefor

摘要

A JPEG 2000 steganography apparatus and a method thereof for minimizing the change of the code block noise variance predicting the change of the code block noise variance are provided to prevent the detection by steganalysis based on HHT(Hilbert-Huang Transform) by inserting a message. An image encoding unit(100) generates bit stream by encoding the image data. A code block predicting unit(200) inputs the bit stream. The code block estimator produces the low-precision code block dispersion and low coarse code block noise variance about each code block. The code block estimator produces the order of the layer. An order weight calculator(300) inputs the calculated return value. The order weight calculator produces the order weighted value by using the return value which is input. A message processor(400) inserts and extracts the bit stream.