Method and Apparatus for Digital Watermark on Rational Bezier Curves and Surfaces

摘要

The present invention relates to how the digital watermark of the curve / surface and an apparatus for glass Bezier having a resistance to re-parametric, water a polynomial to the watermark information to the yield ratio by multiplying the same time the numerator and the denominator of the curve in the glass Bezier the mark information can be inserted in the original data, it is possible to calculate the yield ratio of a common root for the control point function of the curve to the free Bezier material parametric and extracting watermark information from the yield ratio. Accordingly, the watermark even if the geometric transformation the inserted watermark, such as a material parameter to the digital content insertion screen is retained, and that the effect is maintained without the watermark disappear even for dividing enhance copyright protection of digital content, as well as in particular the effect that the watermark is maintained even re-parametric CAD data.