• Title/Summary/Keyword: mobile streaming

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Design and Implementation of Adaptive Streaming System for Seamless Multimedia Transmission (끊김 없는 멀티미디어 전송을 위한 적응적인 스트리밍 시스템의 설계 및 구현)

  • Kim, Hyung-Jun;Lee, Sung-Hee;Koo, Ja-Hon;Oh, Seoung-Jun;Jung, Kwang-Su
    • Proceedings of the Korean Information Science Society Conference
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    • 2010.06d
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    • pp.301-305
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    • 2010
  • 최근 무선 네트워크 서비스의 수요가 증가함에 따라 낮은 비용, 간편한 설치 그리고 높은 대역폭 특성을 가지는 무선랜 (WLAN)을 기반으로 한 사내 네트워크 구성이 학교 및 기업을 중심으로 증가하고 있다. 이로 인해 사내 네트워크를 통한 랩탑 (Laptop), 넷북 (Notebook), 스마트 폰 (Smart Phone), 그리고 UMPC (Ultra Mobile Personal Computer)등 휴대용 단말을 이용한 스트리밍 서비스의 수요가 증가하고 있다. 하지만 무선랜 환경은 사용자 이동에 의해 핸드오버가 발생할 경우, 이동할 대상 네트워크의 혼잡 상태를 고려하지 않는다. 따라서 이동할 네트워크에 빠르게 적응하지 못함으로써 패킷 손실에 의한 서비스의 불연속성 문제가 발생할 수 있다. 본 논문에서는 이러한 문제점을 해결하기 위해 핸드오버 이전에 이동 대상 네트워크의 혼잡 상태를 인지하여 전송률을 조절함으로써, 스트리밍 서비스의 불연속성 문제를 해결하는 적응적인 스트리밍 시스템을 설계 및 구현하였다. 제안하는 시스템은 핸드오버 이전에 이동 대상 네트워크의 가용대역폭을 측정하여 혼잡 상태를 인지하고, 측정한 가용대역폭 값을 기반으로 전송하는 프레임의 수를 우선순위에 따라 차등적으로 조절하여 전송률을 조절하였다.

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Efficient Soft Handover method for Bluetooth (블루투스를 위한 효율적 소프트 핸드오버 방안)

  • Choi, Eun-Seok;Jeong, Myoung-Soon;Oh, Hoon;Park, Hong-Seong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.3A
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    • pp.266-275
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    • 2004
  • Recently, wireless networks require an efficient handover scheme due to increase of mobile devices. But Bluetooth has several problems to support the efficient handover, which are the additional increase of signaling traffic and long time of the initial setup processes of inquiry and paging processes. This paper suggests an efficient Soft Handover method for Bluetooth (eSoHoB), which reduces the eplased time of the inquiry and paging process and supports a soft handover using the anticipation method. This paper implements the eSoHoB using two Bluetooth hardware modules and a testbed to be able to receive streaming data while a Bluetooth terminal is moving. This paper measures handover delays and the operation of the soft handover to verify the proposed mhthod.

An Efficient Transmission Scheme of MPEG2-TS over RTP for a Hybrid DMB System

  • Seo, Hyung-Yoon;Bae, Byungjun;Kim, Jong-Deok
    • ETRI Journal
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    • v.35 no.4
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    • pp.655-665
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    • 2013
  • Hybrid digital multimedia broadcasting (DMB) is a next-generation mobile TV system that combines broadcasting and wireless communication networks and can provide various high-quality multimedia services. However, if a system adheres to the current standard of transmitting the DMB content in the form of MPEG2-TS through wireless networks, it results in a burden on the network due to low transmission efficiency. The reasons for the low transmission efficiency are as follows. First, due to its constant bitrate characteristic, DMB MPEG2-TS includes a considerable amount of needless information, such as NULL packets and stuffing bytes. Second, due to the inflexibility of the Real-time Transport Protocol (RTP) standard, one cannot fully utilize the maximum transmission unit of the network when converting MPEG2-TS to RTP stream for transmission. This paper proposes a new transmission scheme that resolves these problems. Experiment results show that the proposed scheme improves data bitrate transmission efficiency by 8% to 36%, compared to the standard scheme, in the streaming of various real-DMB contents.

The Implementation of Fast Object Recognition Using Parallel Processing on CPU and GPU (CPU와 GPU의 병렬 처리를 이용한 고속 물체 인식 알고리즘 구현)

  • Kim, Jun-Chul;Jung, Young-Han;Park, Eun-Soo;Cui, Xue-Nan;Kim, Hak-Il;Huh, Uk-Youl
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.5
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    • pp.488-495
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    • 2009
  • This paper presents a fast feature extraction method for autonomous mobile robots utilizing parallel processing and based on OpenMP, SSE (Streaming SIMD Extension) and CUDA programming. In the first step on CPU version, the algorithms and codes are optimized and then implemented by parallel processing. The parallel algorithms are debugged to maintain the same level of performance and the process for extracting key points and obtaining dominant orientation with respect to key points is parallelized. After extraction, a parallel descriptor via SSE instructions is constructed. And the GPU version also implemented by parallel processing using CUDA based on the SIFT. The GPU-Parallel descriptor achieves an acceleration up to five times compared with the CPU-Parallel descriptor, but it shows the lower performance than CPU version. CPU version also speed-up the four and half times compared with the original SIFT while maintaining robust performance.

Energy-Efficient Discrete Cosine Transform on FPGAs (FPGA 상에서 에너지 효율적인 DCT (Discrete Cosine Transform) 모듈 설계 및 구현)

  • Jang Ju-wook;Lim Chang-hyeon;Scrofano Ronald;Prasanna Viktor K.
    • The KIPS Transactions:PartA
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    • v.12A no.4 s.94
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    • pp.313-320
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    • 2005
  • The 2-D discrete cosine transform (DCT) is an integral part of video and image processing; it is used in both the PEG and MPEG enciding standards. As streaming video is brought to mobile devices, it becomes important that it is possible to calculate the DCT in an energy-efficient manner. In this paper, we present a new algorithm the DCT with a linear array PEs. This design is optimized for energy efficiency. We analyze the energy, area, and latency tradeoffs available with this design and then compare its energy dissipation, area, and latency to those of Xilinx's optimized IP core.

Performance Analysis of Mobile node based on SCTP in MIPv6 (MIPv6에서 SCTP 기반 이동단말의 성능 분석)

  • Kim, Gwang-Hyun;Cho, Chung-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.8
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    • pp.1391-1400
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    • 2008
  • In recent yeats, SCTP is known as the next transport layer protocol for connection-oriented and reliable data transfer after TCP/UDP. The SCTP was developed on the basis of the existing TCP and was designed to eliminate defects of TCP. SCTP has the different characteristic of multi-streaming and multi-homing from TCP. In this paper, we studied the defects of the performance of communication using the traits of multi-homing. And we evaluated the efficiency for each application services on the basis of SCTP of IPv6. Also, we analysed the delay time of a packet using SCTP and TCP. We noticed that the efficiency of SCTP is better than that of TCP.

A Study on the Service Provision Direction of the National Library for Children and Young Adults in the 5G Era

  • Noh, Younghee;Ro, Ji Yoon
    • International Journal of Knowledge Content Development & Technology
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    • v.11 no.2
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    • pp.77-105
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    • 2021
  • In order to establish a digital-based use environment for the provision of new information services suitable for the 5G era, it is necessary to discuss the direction of service provision by the National Library of Children and Young Adults in the 5G era. Based on utilization services in other fields, library services in the 5G era, including the development and provision of employee education and training services, ultra-high-definition and 360-degree realistic contents and education on library use, provision of multi-dimensional realistic media streaming broadcasting services, provision of telepresence education programs, activation of virtual communities, implementation of hologram performance halls/exhibit centers, and provision of unmanned book delivery services, environment monitoring, safety monitoring, and customized services, were proposed. In addition, based on 5G service, 5G technology, and library application direction, advancing into a producing and supporting base for ultra-realistic and immersive contents in the 5G era, strengthening online and mobile services in the non-contact era, and establishing a smart library environment were proposed as the service provision direction for the National Library of Children and Young Adults in the 5G era.

Deep Learning based Adaptive Video Streaming with Mobile Data Usage (모바일 데이터 사용량을 고려한 딥러닝 기반 적응형 비디오 스트리밍)

  • Kim, Minseob;Hur, Sungjae;Lee, Heejong;Vu, Van Son;Choi, Minje;Lim, Kyungshik
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • fall
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    • pp.225-228
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    • 2021
  • 최근 모바일 비디오 스트리밍 서비스의 이용자 수가 증가하고 있다. 이에 따라 모바일 환경에 적합한 DASH 비디오 스트리밍 메커니즘이 연구되었고, 이것을 DQN 기법에 의해 개선한 알고리즘은 모바일 네트워크 환경에서 적절한 비디오 품질 선택을 통해 버퍼링을 크게 줄일 수 있었다. 그러나 이는 모바일 요금제로 비디오 스트리밍 서비스를 이용하는 사용자들에게 안정적인 서비스를 제공하기 어렵다. 이에 본 논문은 기존의 DQN 기법에 의한 알고리즘을 발전시켜 사용자의 모바일 요금제에 적합한 비디오 품질을 선택하는 알고리즘을 연구하고 성능 실험 결과를 분석한다. 또한 이 알고리즘을 전체 모바일 비디오 스트리밍 시스템과 통합하여 이용하도록 제안한다.

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Audio Quality Enhancement at a Low-bit Rate Perceptual Audio Coding (저비트율로 압축된 오디오의 음질 개선 방법)

  • 서정일;서진수;홍진우;강경옥
    • The Journal of the Acoustical Society of Korea
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    • v.21 no.6
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    • pp.566-575
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    • 2002
  • Low-titrate audio coding enables a number of Internet and mobile multimedia streaming service more efficiently. For the help of next-generation mobile telephone technologies and digital audio/video compression algorithm, we can enjoy the real-time multimedia contents on our mobile devices (cellular phone, PDA notebook, etc). But the limited available bandwidth of mobile communication network prohibits transmitting high-qualify AV contents. In addition, most bandwidth is assigned to transmit video contents. In this paper, we design a novel and simple method for reproducing high frequency components. The spectrum of high frequency components, which are lost by down-sampling, are modeled by the energy rate with low frequency band in Bark scale, and these values are multiplexed with conventional coded bitstream. At the decoder side, the high frequency components are reconstructed by duplicating with low frequency band spectrum at a rate of decoded energy rates. As a result of segmental SNR and MOS test, we convinced that our proposed method enhances the subjective sound quality only 10%∼20% additional bits. In addition, this proposed method can apply all kinds of frequency domain audio compression algorithms, such as MPEG-1/2, AAC, AC-3, and etc.

Efficient Transmission of Scalable Video Streams Using Dual-Channel Structure (듀얼 채널 구조를 이용한 Scalable 비디오(SVC)의 전송 성능 향상)

  • Yoo, Homin;Lee, Jaemyoun;Park, Juyoung;Han, Sanghwa;Kang, Kyungtae
    • KIPS Transactions on Computer and Communication Systems
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    • v.2 no.9
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    • pp.381-392
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    • 2013
  • During the last decade, the multitude of advances attained in terminal computers, along with the introduction of mobile hand-held devices, and the deployment of high speed networks have led to a recent surge of interest in Quality of Service (QoS) for video applications. The main difficulty is that mobile devices experience disparate channel conditions, which results in different rates and patterns of packet loss. One way of making more efficient use of network resources in video services over wireless channels with heterogeneous characteristics to heterogeneous types of mobile device is to use a scalable video coding (SVC). An SVC divides a video stream into a base layer and a single or multiple enhancement layers. We have to ensure that the base layer of the video stream is successfully received and decoded by the subscribers, because it provides the basis for the subsequent decoding of the enhancement layer(s). At the same time, a system should be designed so that the enhancement layer(s) can be successfully decoded by as many users as possible, so that the average QoS is as high as possible. To accommodate these characteristics, we propose an efficient transmission scheme which incorporates SVC-aware dual-channel repetition to improve the perceived quality of services. We repeat the base-layer data over two channels, with different characteristics, to exploit transmission diversity. On the other hand, those channels are utilized to increase the data rate of enhancement layer data. This arrangement reduces service disruption under poor channel conditions by protecting the data that is more important to video decoding. Simulations show that our scheme safeguards the important packets and improves perceived video quality at a mobile device.