• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.366-370
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• 2007

This paper discusses a most suitable wireless communications system for subway trains on condition that a geo-spatial video system is implemented in subway trains. Geo-spatial video system for subway trains refers to the device that can transfers the images captured by cameras within a subway station building or in and around a subway track to on coming trains wirelessly, which allows the operator in operating room to monitor the state of a platform and a subway track, the flow of passengers, and the condition of passengers getting on and off. To minimize the problem, secure civil safety and prevent accidents and calamity from occurring, a geo-spatial video system for subway trains has been increasingly introduced. The wireless communications systems for GVS for subway trains involve HF(High Frequency), IR(Infra Red), M/W(Micro Wave), wireless LAN approaches. Each has its own strengths/weaknesses, and different vendors have different technology.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.609-614
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• 1999

Our present ability to work with video has not been confined to wired communication environment. This paper describes the new technological trend of wireless video communication. In wireless video communication, unlike wired network, several techniques are needed. At first, error robust video coding is essential. Due to characteristics of wireless channel, the system is exposed to more error prone environment. In addition, encoded video bit streams are vulnerable to the error because of the entropy coding. Recently many frameworks are developed to cope with this problem. We just explore the numerous robust video coding approaches with the viewing of error control. And more we discuss other on going research topics in this wireless video communication fields like low-power assumption design, trans-codec technique, and rate control schemes in brief.

• ETRI Journal
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• v.35 no.1
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• pp.27-34
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• 2013

This paper proposes a network-adaptive mechanism for HTTP-based video streaming over wireless/mobile networks. To provide adaptive video streaming over wireless/mobile networks, the proposed mechanism consists of a throughput estimation scheme in the time-variant wireless network environment and a video rate selection algorithm used to increase the streaming quality. The adaptive video streaming system with proposed modules is implemented using an open source multimedia framework and is validated over emulated wireless/mobile networks. The emulator helps to model and emulate network conditions based on data collected from actual experiments. The experiment results show that the proposed mechanism provides higher video quality than the existing system provides and a rate of video streaming almost void of freezing.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.7
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• pp.1571-1578
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• 2014

Binary CDMA is a new standard technology for wireless communication developed by our country that makes high speed communications and good quality of services for multimedia data such as voice and video. In this paper we researched the design and implementation of a wireless Video Transmitter and Video Server - the main devices for the Automobile Wireless Camera System - based on the Binary-CDMA technology that makes them freely installed in any place without wired cables restriction.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.1
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• pp.1-10
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• 2023

In this paper, the design and implementation of the long-distance wireless transmission technology of high-definition video using domestic wireless communication technology for the existing wired-based CCTV surveillance system and IP camera system was evaluated for performance. The interworking test between the wireless multi-IP camera transmission terminal device and the wireless communication RF module, and the wireless multi-IP camera-based video transmission system integration interworking test confirm the module interworking suitability during video transmission.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.4
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• pp.381-391
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• 2013

Wireless transmission of uncompressed video guarantees higher quality with lower latency than compressed video transmission. Although current wireless technologies cannot fully cover required data rates of about a few Gb/s for full high definition resolution, some wireless technologies such as ultra-wideband (UWB) provide 1 Gb/s data rate which is adequate for uncompressed video transmission in portable devices. In this paper, we propose an uncompressed video transmission system for wireless mirroring services in portable devices. We firstly simulated the performance of uncompressed video transmission using single or multiple 1 Gb/s UWB technology. Then we implemented hardware-based uncompressed video processing block and Gb/s wireless MAC accelerator. Finally, we show the implementation result and the demonstration of uncompressed HD video transmission using multiple 1 Gb/s UWB PHYs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.2B
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• pp.110-119
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• 2012

In this paper, we propose an efficient video streaming system over heterogeneous wireless networks. The proposed system modifies fountain code for the video streaming service and maximizes the target video encoding rate using multiple paths while satisfying delay and block recovery failure rate constraints of fountain code. Finally, the proposed system provides the seamless video streaming service of high quality to subscribers by dynamic adaptation of control parameters based on the states of each path over heterogeneous wireless networks.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.8B
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• pp.707-715
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• 2006

One of the most promising services on the wireless network is multimedia data service. With recently emerged wireless communication technologies which conventionally were devoted to mobile phone services, pre-encoded contents as well as live video data can be transmitted via the same network. As there is enough room in the improvement of data transmission bandwidth in wireless network, video data service is likely to be more demanding. In this paper, real time MPEG-4 video encoder is described as apart of a whole system for live video services over wireless networks. As there are minimal assumptions on the underlying networks, presented system and service can be easily supported by different network system.

• Journal of Information Processing Systems
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• v.19 no.6
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• pp.817-829
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• 2023

Variable wireless channel is a big challenge for real-time video applications, and the rate adaptation of realtime video streaming becomes a hot topic. Intra-video coding is important for high-quality video communication and industrial video applications. In this paper, we proposed a novel adaptive scheme for real-time video transmission with intra-only coding over a wireless network. The key idea of this scheme is to estimate the instantaneous remaining capacity of the network to adjust the quality of the next several video frames, which not only can keep low queuing delay and ensure video quality, but also can respond to bandwidth changes quickly. We compare our scheme with three different schemes in the video transmission system. The experimental results show that our scheme has higher bandwidth utilization and faster bandwidth change response, while maintaining low queuing delay.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.287-290
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• 2003

In recent years, one of the main trends of GIS is to construct and provide realistic and human-perceptible information of spatial object using video data. The rapid progress of wireless mobile technology makes the multimedia source using video data possible on mobile environment. Instead of traditional map-based service, video-based location services, that provide video data as location context, would be of interest in connection with various mobile applications requiring location service, such as telematics, LBS, etc. In this paper, we present the location service system using geo-referenced video on wireless mobile environment.