• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.5
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• pp.44-56
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• 2009

Multimedia streaming service is susceptible to loss and delay of data as it requires high bandwidth and real time processing. Therefore QoS cannot be guaranteed due to data loss caused by heavy network traffic and error of wireless channel. To solve these problems, studies about algorithms which improve the quality of multimedia by serving differently according to the priority of packets in multimedia stream. Two algorithms are proposed in this paper. The first algorithm proposed is WMS-1(Wireless Multimedia Scheduling-1) algorithm which acts like IWFQ when any wireless loss is occurred but assigns channels first in case of urgent situation like when the running time of multimedia runs out. The second algorithm proposed is WMS-2(Wireless Multimedia Scheduling-2) algerithm that assigns priority to multimedia flow and schedules flow that has higher priority according to type of frame first. The comparison with other existing scheduling algorithms shows that multimedia service quality of the proposed algorithm is improved and the larger the queue size of base station is, the better total quality of service and fairness were gained.

• Journal of Korea Multimedia Society
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• v.14 no.6
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• pp.759-765
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• 2011

In this paper, we proposed fast stream cipher MS64 for use mobile that it is secure, fast, and easy to implement software. The proposed algorithm use the fast operating 213-bit arithmetic shift register(ASR) to generate a binary sequence and produce 64-bit stream cipher by using simple logical operation in non linear transform. MS64 supports 128-bit key in encryption algorithm and satisfy with the safety requirement in modern encryption algorithm. In simulation result shows that MS64 is faster than a 32-bit stream cipher SSC2 in the speed of operation with small usage of memory thus MS64 can be used for mobile devices with fast ciphering.

• Journal of Advanced Navigation Technology
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• v.6 no.4
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• pp.290-295
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• 2002

In Mpeg-4 system, objects are composed of ES(Elementary Stream). Each of the objects is managed independently by object-based coding and is transmitted via DMIF(Delivery Multimedia Integration Framework). The data streams in Mpeg-4 are transmitted with using DVB-Data Carousel which can improve the reliability and efficiency by cyclic retransmission. This paper describes a system which transmits some part of data stream of Mpeg-4 object with using DVB-Data Carousel to clients via satellite. This also uses a performance enhancing proxy server for reducing round trip time between ground network and satellite.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.515-518
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• 1998

This paper describes a direct transfer method of multimedia data stream between multimedia processor and network device without using system memory. The hardware architecture and functions for direct transfer, the method to transfer multimedia data to and from the multimedia processor and etc are described. Comparing the proposed method with general methods, I show that the direct transfer method can decrease number of bus accesses and bus cycles.

• Journal of the Korea Society for Simulation
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• v.12 no.4
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• pp.95-102
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• 2003

Stream servers are for supplying multimedia stream data to users through the internet such as movies and music without discontinuation. A typical stream server is designed roughly by considering the characteristics of stream services and by employing processors, memory, PCI bus, Ethernet, TOE and disks. This study focuses on deciding the priority for using resources such as PCI bus, buffer memory and TOE buffer, which have limited capacities in a typical stream server. When the priorities for using limited resources are not given properly, the stream servers may not even function as originally designed. The simulation study shows that the top priority for using PCI bus for normal streaming services should be given to the operation that sends data from buffer memory to TOE buffer. Giving priority for using PCI bus to other operation such as sending data from disks to memory results in a deadlock phenomenon.

• Journal of Korea Multimedia Society
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• v.15 no.1
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• pp.87-92
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• 2012

Wireless sensor network is a technology that collects the information about object in real-time. Sensor data has a characteristic that is generated an unprecedented volume data in short time. Analysis is essential to define the relationship between the data, including more of the data from a large volume data stream which is acquired from the sensor. In order to effectively handle the sensor data stream, in this paper, using ECA rules to organize data in a meaningful and more practical real-time monitoring systems is proposed.

• Journal of Multimedia Information System
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• v.4 no.1
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• pp.19-26
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• 2017

The compression of video for both full HD and UHD requires the inclusion of extra vertical lines to every video frame, named as the DTV essential hidden area (DEHA), for the effective functioning of the MPEG-2/4/H encoder, stream, and decoder. However, while the encoding/decoding process is dependent on the DEHA, the DEHA is conventionally viewed as a redundancy in terms of channel utilization or storage efficiency. This paper proposes a block mode DEHA method to more effectively utilize the DEHA. Partitioning video block images and then evenly filling the representative DEHA macroblocks with the average DC coefficient of the active video macroblock can minimize the amount of DEHA data entering the compressed video stream. Theoretically, this process results in smaller DEHA data entering the video stream. Experimental testing of the proposed block mode DEHA method revealed a slight improvement in the quality of the active video. Outside of this technological improvement to video quality, the attractiveness of the proposed DEHA method is also heightened by the ease that it can be implemented with existing video encoders.

• Journal of Communications and Networks
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• v.5 no.3
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• pp.258-265
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• 2003

Transmission of continuous media streams has been a challenging problem of multimedia service. Lots of works have been done trying to figure out the best solution for this problem, and some works presented the optimal solution for transmitting the stored video using smoothing schemes applied to each individual stream. But those smoothing schemes considered only one stream, not the whole streams being serviced, to apply themselves, which could only achieve local optimum not the global optimum. Most of all, they did not exploit statistical multiplexing gain that can be obtained before smoothing. In this paper, we propose a new smoothing scheme that deals with not an individual stream but the whole streams being serviced simultaneously to achieve the optimal network bandwidth utilization and maximize the number of streams that can be serviced simultaneously. We formally proved that the proposed scheme not only provides deterministic QoS for each client but also maximizes number of clients that can be serviced simultaneously and hence achieves maximum utilization of transmission bandwidth.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.04a
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• pp.1166-1171
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• 2000

기존의 멀티미디어 연구의 실현에 있어 가장 큰 문제라 할 수 있던 성능의 문제가 하드웨어의 급속한 발달로 해결되어 감에 따라 멀티미디어 및 제반 관련기술도 함께 발전되었으며 이에 기반한 multimedia stream에서의 event를 검출하기 위한 다양한 연구들이 진행되어 왔다. 그러나 지금까지의 연구는 주로 전송 및 저장, 검색에 집중되어 연구되어 왔으며 영상인식 등의 Vision관련 연구에서는 멀티미디어 스트리밍 기술과의 연동을 고려하지 않은 연구를 수행함에 따라 검출 가능한 event가 있다고 하더라도 응용영역에 종속적인 인테페이스만을 고려함에 따라 사용자가 이를 기술(記述, description)하거나, 사용자에게 검출 가능한 event를 제시하기 위해 일반화된 방법이 제시되어 있지 않았다. 본 연구에서는 사용자가 검출을 원하는 event를 기술하는 방법과, 시스템에서 검출 가능한 event를 제시하기 위한 방법을 제안하고, 제시되는 방법이 응용영역에 독립적이기 위해 요구되는 사항들과 객체 단위인 이벤트/행위와 처리기 사이의 인터페이스에 관하여 정의한 후 기본적인 동작방식을 제안한다.

• Journal of Broadcast Engineering
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• v.8 no.3
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• pp.259-267
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• 2003

In this paper, we propose a media processor to provide interactive services in mobile multimedia broadcasting environments. The proposed system Is designed to support various functionalities, such as generation of MPEG-4 IOD (Initial Object Descriptor)/OD(Object Descriptor)/BIFS (Binary Format for Scene) data, encapsulation of MPEG-4 AVC (Advanced Video Coding)/BSAC (Bit Sliced Arithmetic Coding) stream and generated IOD/OD/BIFS data into SL (Sync Layer) packet, packetization of SL packet into TS (Transport Stream) packet and multiplexing. The proposed media processor can provide MPEG-4 based interactive services for users.