SVD-based watermark with quasi-one-way operation by reducing a singular value matrix rank
Kazuo Ohzeki, Masaru Sakurai · 2008
A new Singular Value Decomposition (SVD)-based watermarking method was developed in this study. Quasi-one-way operation is improved by reducing the rank of the singular value matrix. All diagonal elements of the singular value matrix are positive; all other off-diagonal elements are zeros. To add an element to the off-diagonal area is fundamentally a quasi-one-way operation because no value cannot be subtracted from zero. In adding elements to the off-diagonal area, a pair of linearly dependent vectors is produced. This modification reduces the rank of the singular value matrix. It is computationally difficult to find diminished singular values from the reduced rank matrix.