Blind wavelet-based watermarking method
AssigneeNational Taiwan University of Science and Technology
InventorsJing-Ming Guo, Yu-Quan Tzeng
Life of this patent
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Abstract
A blind wavelet-based watermarking method is provided to extract one or more embedded watermarks form one or more high subbands of a watermarked image generated by 1-level or 2 level wavelet transform. One or more least-mean-square (LMS) filters are trained to predict the data sets in the high subbands of an original image by converting a low subband of the watermarked image. Therefore, the one or more embedded watermarks could be extracted by comparing the predicted data sets in the high subbands with data sets in corresponding subbands of the watermarked image.
Claims4
A blind wavelet-based watermarking method for extracting at least one hidden watermark from a watermarked image, the method comprising:
- performing a wavelet transform to decomposed the watermarked image into a first data set in a subband LL1, a second data set in a subband LH1, a third data set in a subband HL1 and a fourth data set in a subband HH1;
- converting the first data set in the subband LL1 into a first predicted data set in the subband LH1, into a second predicted data set in the subband HL1, and into a third predicted data set in the subband HH1 via three LMS (least-mean-square) filters;
- and
- extracting the at least one hidden watermark by comparing the first predicted data set with the second data set, comparing the second predicted data set with the third data set, or comparing the third predicted data set with the fourth data set.
Dependencies are inferred from the claim text.