Lossless Information Hiding in Images

3.4. Integer Wavelet Transform–Based Schemes

In this section, we turn to integer wavelet transform–based lossless information hiding schemes, which adopt the so-called CDF(2,2) wavelet. Thus, we first introduce related concept of the CDF(2,2) wavelet.

The CDF(2,2) wavelet was proposed by Cohen, Daubechies, and Feauveau in 1992 [14]; it is a dual orthogonal (i.e., biorthogonal) (5,3) wavelet, whose low-pass and high-pass filters are with lengths of 5 and 3, respectively, both presenting symmetry. We can obtain an integer-to-integer bijective CDF(2,2) wavelet by lifting the original CDF (2,2) wavelet based on a certain lifting scheme, and this type of integer wavelet has been adopted in the JPEG2000 standard. Experiments have shown that, compared ...