• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1101-1104
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• 1998

The modern multimedia applications which are video processor, video conference or video phone and so forth require real time processing. Because of a large amount of image data, those require high compression performance. In this paper, the prosposed image processing encoder was designed by using wavelet transform encoding. The proposed filter block can process imae data on the high speed because of composing individual function blocks by parallel and compute both highpass and lowpass coefficient in the same clock cycle. When image data is decomposed into multiresolution, the proposed scheme needs external memory and controller to save intermediate results and it can operate within 33MHz.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.1
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• pp.73-81
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• 2003

An autonomous stair robot recognizing the stair, and climbing up and down the stair by utilizing a robot vision, photo sensors, and appropriate climbing algorithm is introduced. Four arms associated with four wheels make the robot climb up and down more safely and faster than a simple track typed robot. The robot can adjust wheel base according to the stair width, hence it can adopt to a variable width stair with different algorithms in climbing up and down. The command and image data acquired from the robot are transferred to the main computer through RF wireless modules, and the data are delivered to a remote computer via a network communication through a proper data compression, thus, the real time image monitoring is implemented effectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.108-111
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• 2008

In this paper, we propose an advanced hardware architecture for the CAVLC entropy encoder engine for real time Full HD video compression. Since there are 384 data coefficients which are sum of 376 AC coefficient and 8 DC coefficient per one macroblock, 384 coefficient have to be processed per one macroblock in worst case for real time processing. We propose an novel architecture which includes parallel architecture and pipeline processing, and reduction "0" in AC/DC coefficient table. To verify the proposed architecture, we develop the reference C for CAVLC and verified the designed circuit with the test vector from reference C code.

• Journal of Korea Multimedia Society
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• v.12 no.2
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• pp.257-271
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• 2009

In this paper, we propose a protocol compression scheme for enhancing the performance of call processing of PTT(Push-to-Talk) which is one of the important services in IMS(IP Multimedia Subsystem), a next generation integrated wired/wireless packet communication network. To service the PTT on an IMS network, it should use the same call setup procedure as legacy Mobile and TRS(Trunked Radio System) networks and have a fast call setup time and enough communication bandwidth because a number of terminals should be able to exchange same data in real time. The proposed A+SigComp scheme reduces the initial call setup delay of SIP by about 10%, which is used by PTT service for call setup. In addition, the A+ROHC scheme is proposed to compress the header of RTP packets transferred during PTT voice transmission and, as a result, about 5% of increase in communication efficiency is observed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.13 no.5
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• pp.390-399
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• 1988

A conventional BTC has the merit of real time processing and simple computation, but has the problem that its compression rate is low. In this paper, a modified BTC using the Quad Tree which is frequently used in binary image is proposed. The method results in the low compression rate by decreasing the total number of subblocks by mean of making the size of a subblock large in the small variation area of graty level and the size af a subblock small in the large variation area of gary level. For the effective transmission of bit plane, the Huffman run-lengh code for the large size of a subblock and the lookup table for tha small size of a subblock are used. The proposed BTC method show the result of coding 256 level image at the average data rate of about 0.8 bit/pixel.

• The Transactions of the Korea Information Processing Society
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• v.3 no.1
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• pp.9-32
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• 1996

In this paper, we describe a multimedia data processing model that supports wide variety of applications based on multimedia production model. This model supports network-transparent access to stored multimedia data, real-time mult media input devices, and multimedia processing. The model addresses real-time dato a switching and delivery, as well as acquisition, processing, and output. Most translation, compression, and synchronization services are integrated. This model consists of three layers: (1) stream, (2) multimedia presentation, (3) hyperpresentaion. This paper describes the data abstractions associated with each layer. These data abstractions provide a framework for defining the services provided by each layer, and describe the object-oriented mechanisms that provide those services. A sample scenario is presentated to illustrate the use of this model. A server-client architecture and implementation issues, and future directions are also discussed. sed.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.388-390
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• 2004

In this paper, we performed the implementation of image transmission server system using embedded system that is for the specified object and easy to install at any places and move to wherever. Since the embedded system has lower capability than PC, we have to reduce the quantity of calculation and transmission. The image compression like JPEG, needs that the server calculates for making compressed image, makes the server carry the load. So we compresses the image at the server and transmit the codes to the clients connected, then the received codes from server are decoded and displayed at the clients. In this process to make the image compression and transmission effectively, we decrease the procedure as simple as possible to transmit the data in almost real-time. We used the Redhat linux 9.0 OS at the host PC and the target board based on embedded linux. The image sequences are obtained from the camera attached to the FPGA board with ALTERA chip. For effectiveness and avoiding some constraints, we made the device driver. Generally the image transmission server is PC, but using the embedded system as a server makes the server portable and cheaper than the system based on PC.

• Journal of Broadcast Engineering
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• v.15 no.3
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• pp.355-361
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• 2010

Video Compression is the key technology for the transmission of multi-media data. Because the Motion Estimation is the most complex module in the video compression, fast motion estimation algorithm is essential for the real-time application. In this paper, we propose an enhanced binary motion estimation algorithm based on the wavelet transform. Proposed algorithm improve the quality of coded video.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.1
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• pp.14-19
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• 2007

As XML is used by standard format for information expression and information exchange in various field, Many Company began to use SVG by user interface or information expression tool of embedded system such as mobile phone based wireless internet. Because SVG has many additional information to keep structure of SVG document exception real data, there is a problem that transfer time of SVG file is so cost for quantity of transmitted data actually. To solve this problem, many researches using compression conception have been conducted for applying to an embedded system. This paper proposes SMETA that can use existing researches using compression concept at once. SMETA divides SVG file to each part that can allocate meaning, and gives semantic metadata to each part without alteration of SVG structure. SMETA can reduce site of transmitted SVG file actually by transmitting specification part of SVG file that metadata does not agree or has unlisted part in an embedded system between an embedded system and server, before transmit whole SVG file. By size of transmitting SVG file is decreasing, transfer time can be shortened accordingly.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.4
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• pp.42-50
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• 2008

The real-time bio-signal monitoring system based on the ZigBee and SIP/RTP has proposed and implemented for telemedicine but that has some problems at the stabilities to transmit bio-signal from the sensors to the other sides. In this paper, we designed and implemented a real-time bio-signal monitoring system that is focused on the reliability and efficiency for transmitting bio-signal at real-time. We designed the system to have enhanced architecture and performance in the ubiquitous sensor network, SIP/RTP real-time transmission and management of the database. The Bluetooth network is combined with ZigBee network to distribute traffic of the ECG and the other bio-signal. The modified and multiplied RTP session is used to ensure real-time transmission of ECG, other bio-signals and speech information on the internet. The modified ECG compression method based on DWLT and MSVQ is used to reduce data rate for storing ECG to the database. Finally we implemented a system that has improved performance for transmitting bio-signal from the sensors to the monitoring console and database. This implemented system makes possible to make various applications to serve U-health care services.