Sanghyun Joo

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SUMMARY We introduce an extended EZW coder that uses flexible zerotree coding of wavelet coefficients. A flexible parent-child 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)
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)
Digital image watermarking is implemented using fuzzy logic approach based on transform domain. Fuzzy logic is an approach based on "degrees of truth" rather than usual "true or false" i. e. , Boolean logic. In this paper, we use a reference image instead of original image. To get a reference image Directive contrast and Threshold value are calculated for(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)