Sanghyun Joo

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In this paper a novel watermarking method based on discrete wavelet transform (OW) is proposed. Different from previous watermarking methods, the watermark is embedded into the middle fiequency coefficients by quantizing middle frequency coefficient pair, which is defined as a pair of coefficients that are at the same location in LH and HL bands of DWT(More)
WC introduce a new zzrotree scheme that e&tively exploits the inter-scale self-similaritizs found in the octave decomposition hy a wavelet transform. :2 zerotreti is useful to code wavelet coefiicients and its 4&tiveness wa.q proved hy Shapiro’s I:%W. In the coding scheme. wavzlz~ uoellicients are symholizsd and then entropy-coded. ~fhe entropy per symbol(More)
This paper presents an optimal path planning algorithm that adopts the rapidly-exploring random tree(RRT) as a path planner. The RRT generates a valid path quickly, but it does not have the ability to control the quality of the path. In this paper, the nonholonomic path planning and the optimal path planning are tackled simultaneously within the RRT(More)
We introduce an extended EZW coder that uses flexible zerotree coding of wavelet coefficients. A flexible parentchild relationship is defined so as to exploit spatial dependencies within a subband as well as hierarchical dependencies among multi-scale subbands. The new relationship is based on a particular statistics that a large coefficient is more likely(More)
When network and storage devices become more popular, the digital data more easily and more quickly will be distributed. Can be easily pirated copy and did not limit a large number of multimedia information (images, audio and video). Therefore, people are increasingly concerned about the protection of intellectual property rights of multimedia. Digital(More)