• The KIPS Transactions:PartB
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• v.10B no.4
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• pp.419-428
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• 2003

Recently, digital watermarking has been proposed as a viable solution to the need of copyright protection and authentication of multimedia data. A robust wavelet-based watermark casting scheme and a watermark retrieval technique are suggested in this paper. We present a method which can add the watermark to the significant coefficients in the DWT domain, and does not require the original image in the detection process. In adaptive watermark casting method is developed to select perceptually significant coefficients for each subband using multiple threshold. In the proposed method, an adaptive multiple threshold scheme is used to reflect characteristics of each subband and complexity of image. The watermark is adaptively weighted in different subbands to achieve robustness as well as high perceptual quality. The watermark, Gaussian random sequence is added to the large coefficients but not in the lowest subband in the DWT domain. Experimental results show that the proposed algorithm produced visually very good watermarked image which has good invisibility to human eyes and very robust against various image processing and compression attacks.

• Journal of the Korea Convergence Society
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• v.2 no.1
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• pp.7-13
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• 2011

Informations of multimedia centering in the images, are combined acoustic and letter, etc. Although the network advances and the capacity of the storage media extends, these huge informations will not be able to accommodate. From meaning which is like this, International standards for the compression and a multiplexing of image, acoustic and voice H261 where admits standard, JPEG, JBIG, MPEG-l, MPEG-2, MPEG-4 and H263, G series etc, are core techniques of multimedia. At initial step of the base technique which creates the base of like this multimedia service time, we developed the real-time MPEG-4 transmission systems to provides real-time MPEG-4 multimedia services. This system means becomes the base technique which hereafter is developed and is applied various system. This system Will be able to apply from a videoconference, a building protection system and a VOD video system to use the Internet. And, They, the image sensing, embedded linux, and MPEG4 software, will become sourceful technique to develop the different system.

• Journal of Broadcast Engineering
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• v.13 no.4
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• pp.489-500
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• 2008

We propose a novel high-definition content watermarking algorithm that is highly feasible in UCC (User Created Contents) environment. We begin by addressing an association between broadcasting content and UCC in a view of copyrights, then present watermark requirements by analyzing various UCC editing-effect. Also, we provide a brief review of previous watermarking techniques that are supposed to satisfy the requirements. Our proposed scheme inserts a invisible watermark into both DC and AC components on $8{\times}8$ block DCT domain and extracts them after synchronization using DC image. Experimental results show that our technique satisfies the requirements of invisibility and robustness to a variety of attacks such as rotation, scaling, cropping, and JPEG compression, etc. Note that the proposed scheme is highly resilient to UCC edit attacks that are combined by many different types of watermark attacks.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.1
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• pp.55-61
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• 2010

As digital images combined with various types of information became popular, the development of transmission format standard for effective application of imageries is demanded. The purpose of the format standard is to provide a universal format that facilitates the exchange of images and related information. In this paper, we found optimal requirements of imagery transmission format standard after reviewing current state of both military and commercial products and studying functions of various types of format standards including NITF (National Imagery Transmission Format). In addition, future research direction of the imagery transmission format standard that complies with current trend of high-resolution and mass storage imagery data is proposed.

• Journal of the Institute of Convergence Signal Processing
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• v.11 no.2
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• pp.97-103
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• 2010

In this paper, we propose a new digital watermarking technique. The main idea of the proposed algorithm relies on the assumption that any real number can be expressed as a summation of the exponential form with base of 2 and if only consider the first few summations some numbers can be expressed in the same form. Therefore, we can be sure that some amount of changes does not affect the first few summations. The algorithm decomposes a host image in wavelet domain and intensity of the significant wavelet coefficient is expressed in exponential form with base of 2. Multiple barcode watermarks are then embedded by modifying the parity of the exponent. The proposed scheme is semi-blind and also offers either objective or subjective deteew su as well. From extracted watermarks, more accurate watermark is obtained by merging technique as a final watermark. As a simulation result, the proposed algorithm could resist most cases of salt and pepper noise, Gaussian noise and JPEG compression.

• The Journal of the Korea Contents Association
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• v.5 no.6
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• pp.343-350
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• 2005

During the design of a successful digital watermarking systems, Pseudo-Noise(PN) sequences are widely used to modulate information bits into watermark signals. In this method, the number of bits that can be hidden within a small image by means of frequency domain watermarking is limited. In this paper, we show the possibility of introducing chaotic sequences into digital watermarking systems as potential substitutes to commonly used PN-sequences. And we propose a method that transforms the text to chaotic sequence. In our current implementation, we show how the sample text is expressed by an implied unit data(watermark) and the implied unit data is regenerated into the original left. Because we use this implied data as watermark for information hiding, we can insert much more watermark compared with previous method.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.6
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• pp.692-697
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• 2003

The researches on the Internet based tole-operation have received increased attention for the past few years. In this paper, we implement the Internet based tele-operating system. In order to transmit robustly the surroundings and control information of the robot, we make a data as a packet type. Also in order to transmit a very large image data, we use PEG compressive algorithm. The central problem in the Internet based tele-operation is the data transmission latency or data-loss. For this specific problem, we introduce an autonomous mobile robot with a 2-layer fuzzy controller. Also, we implement the color detection system and the robot can perceive the object. We verify the efficacy of the 2-layer fuzzy controller by applying it to a robot that is equipped with various input sensors. Because the 2-layer fuzzy controller can control robustly the robot with various inputs and outputs and the cost of control is low, we hope it will be applied to various sectors.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.5 s.305
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• pp.73-78
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• 2005

Images coded by DCT based compression contain several quality degradations by quantization process. Among them contrast distortion is the important one because human eyes are sensitive to contrast. In case of low bit-rate coded image, we can not get an image having good quality due to quantization error. In this paper, we suggest a new scheme to enhance image's contrast in DCT domain. Proposed method enhances only edge regions. Homogeneous regions are not considered in this method. $8{\times}8$ DCT coefficient blocks are decomposed to $4{\times}4$ sub-blocks for detail edge region discrimination. we could apply this scheme to real-time application because proposed scheme is DCT based method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.10C
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• pp.1484-1489
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• 2004

Given a video frame in terms of its 8${\times}$8 block-DCT coefncients, we wish to obtain a downsized or upsized version of this Dame also in terms of 8${\times}$8 block DCT coefficients. The DCT being a linear unitary transform is distributive over matrix multiplication. This fact has been used for downsampling video frames in the DCT domains in Dugad's, Mukherjee's, and Park's methods. The downsampling and upsampling schemes combined together preserve all the low-frequency DCT coefficients of the original image. This implies tremendous savings for coding the difference between the original frame (unsampled image) and its prediction (the upsampled image).This is desirable for many applications based on scalable encoding of video. In this paper, we extend the earlier works to various DCT sizes, when we downsample and then upsample of an image by a factor of two. Through experiment, we could improve the PSM values whenever we increase the DCT block size. However, because the complexity will be also increase, we can say there is a tradeoff. The experiment result would provide important data for developing fast algorithms of compressed-domain image/video resizing.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.2
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• pp.239-247
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• 2007

In this paper, we propose a system that the Linux is ported in embedded system with peripheral devices of CIS(CMOS Image Sensor) and GPS module. The system acquires GGA sentence from GPS module by recognizing camera and GPS is used module in Linux kernel. And then the received location information is used to include still image acquired through CIS According to this paper, We compose hardware for embedded system, attach board (including camera), port Linux BootLoader and Kernel. And. then we realize that it insert kernel in CIS control device driver and GPS module device driver.