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22
A survey of multimedia streaming in wireless sensor networks
- IEEE Communications Survey & Tutorials
, 2008
"... Abstract—A wireless sensor network with multimedia capa-bilities typically consists of data sensor nodes, which sense, for instance, sound or motion, and video sensor nodes, which capture video of events of interest. In this survey, we focus on the video encoding at the video sensors and the real-ti ..."
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Abstract—A wireless sensor network with multimedia capa-bilities typically consists of data sensor nodes, which sense, for instance, sound or motion, and video sensor nodes, which capture video of events of interest. In this survey, we focus on the video encoding at the video sensors and the real-time transport of the encoded video to a base station. Real-time video streams have stringent requirements for end-to-end delay and loss during network transport. In this survey, we categorize the requirements of multimedia traffic at each layer of the network protocol stack and further classify the mechanisms that have been proposed for multimedia streaming in wireless sensor networks at each layer of the stack. Specifically, we consider the mechanisms operating at the application, transport, network, and MAC layers. We also review existing cross-layer approaches and propose a few possible cross-layer solutions to optimize the performance of a given wireless sensor network for multimedia streaming applications. Index Terms—Cross-layer mechanisms, medium access con-trol, multimedia, video streaming, wireless sensor networks. I.
A JOINT SOURCE-CHANNEL DISTORTION MODEL FOR JPEG COMPRESSED IMAGES
"... The need for efficient joint source-channel coding is growing as new multimedia services are introduced in commercial wireless communication systems. An important component of practical joint source-channel coding schemes is a distortion model to measure the quality of compressed digital multimedia ..."
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Cited by 11 (2 self)
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The need for efficient joint source-channel coding is growing as new multimedia services are introduced in commercial wireless communication systems. An important component of practical joint source-channel coding schemes is a distortion model to measure the quality of compressed digital multimedia such as images and videos. Unfortunately, models for estimating the distortion due to quantization and channel bit errors in a combined fashion do not appear to be available for practical image or video coding standards. This paper presents a statistical model for estimating the distortion introduced in progressive JPEG compressed images due to both quantization and channel bit errors. Important compression techniques such as Huffman coding, DPCM coding, and run-length coding are included in the model. Examples show that the distortion in terms of peak signal to noise ratio can be predicted within a 2 dB maximum error. 1.
UNEQUAL POWER ALLOCATION FOR JPEG TRANSMISSION OVER MIMO SYSTEMS
"... With the introduction of multiple transmit and receive antennas in the next generation wireless standards, realtime image and video communication is expected to become more common. New joint transmission and coding schemes are expected to be developed combining advantages of multiple antenna systems ..."
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Cited by 9 (0 self)
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With the introduction of multiple transmit and receive antennas in the next generation wireless standards, realtime image and video communication is expected to become more common. New joint transmission and coding schemes are expected to be developed combining advantages of multiple antenna systems with source statistics. Based on this idea, we present an unequal power allocation scheme for transmission of JPEG compressed images over multiple-input multiple-output systems employing spatial multiplexing. The JPEG compressed image is divided into different quality layers and different layers are transmitted simultaneously from different transmit antennas using unequal transmit power, with a constraint on the total transmit power during any symbol period. Results show that our unequal power allocation scheme provides significant image quality improvement as compared to different equal power allocations schemes, with the peak-signal-to-noise-ratio gain as high as 15 dB at low signal to noise ratios. 1.
Analysis of audio streaming capability of zigbee networks
- In in Proceedings of Fifth European Workshop on Wireless Sensor Network (EWSN2008
, 2008
"... Abstract. Although formerly conceived for industrial sensing and control over Wireless Sensor Networks, LR-WPANs are registering an increasing interest in experimenting multimedia applications, with particular emphasis on evaluating the streaming capability of Zigbee networks. Due to their limited t ..."
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Cited by 5 (1 self)
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Abstract. Although formerly conceived for industrial sensing and control over Wireless Sensor Networks, LR-WPANs are registering an increasing interest in experimenting multimedia applications, with particular emphasis on evaluating the streaming capability of Zigbee networks. Due to their limited throughput they are not expected to provide high QoS, nevertheless there are several application scenarios such as distributed surveillance, emergency and rescue where audio and video streaming over low cost Zigbee networks is highly desirable. In this paper we first investigate the feasibility of Zigbee-like networks for low-rate voice streaming applications. We analyze important streaming metrics such as throughput, packet loss and jitter in multi-hop topologies. We propose some improvements in the stack implementation and show the performance in order to determine the streaming capacity limits of LR-WPAN networks. 1
A Survey on Multimedia-Based Cross-Layer Optimization in Visual Sensor Networks
- SENSORS
, 2011
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Efficient Feature Distribution for Object Matching in Visual-Sensor Networks
"... version you have downloaded is in pre-print formatting. For the official version please see the publisher's web site: http://dx.doi.org/10.1109/TCSVT.2011.2133330 Copyright (c) 2011 IEEE. Personal use of this material is permitted. However, permission to use this material for any other purposes ..."
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version you have downloaded is in pre-print formatting. For the official version please see the publisher's web site: http://dx.doi.org/10.1109/TCSVT.2011.2133330 Copyright (c) 2011 IEEE. Personal use of this material is permitted. However, permission to use this material for any other purposes must be obtained from the IEEE by sending an email to pubs-permissions@ieee.org.
Research Article Efficient On-Demand Image Transmission in Visual Sensor Networks
"... In a tracking system, an object of interest is monitored continuously in a sensor network. Information about the object is kept in the sensors and sensors transmit the information upon request. In this paper, we consider the scenario where all sensors around a targeted object capture images of it an ..."
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In a tracking system, an object of interest is monitored continuously in a sensor network. Information about the object is kept in the sensors and sensors transmit the information upon request. In this paper, we consider the scenario where all sensors around a targeted object capture images of it and these pictures will be sent to a mobile agent upon request. Due to the size and energy limitations in sensors, images kept in sensors are often small and highly compressed. We describe a framework to facilitate a mobile agent in the sensor network to request images of the object of interest. As sensors are limited in energy, it is desirable to reduce the energy used in transmitting the images. We observe that, in a sensor network that is sufficiently dense, images from neighbor cameras would likely overlap, and therefore intermediate sensors can process and combine overlapping portions so as to reduce the energy spent on image transmission. We develop a protocol for involved sensors to determine how to transmit the images they have kept to the mobile agent in an energy efficient manner. Our protocol is truly distributed and does not require any global information. We evaluate our protocol through extensive simulations. Copyright © 2007 Hindawi Publishing Corporation. All rights reserved. 1.
Energy Efficient High Quality Image Transmission in Wireless Sensor Networks
, 2011
"... (SWC) processing is proposed to maximize compression and minimize energy cost in WSN (Wireless Sensor Network). Most of the current work, utilize lossy image compression techniques to minimize the resource consumption. The lossy image compression technique reduces the size of the image to a great ex ..."
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(SWC) processing is proposed to maximize compression and minimize energy cost in WSN (Wireless Sensor Network). Most of the current work, utilize lossy image compression techniques to minimize the resource consumption. The lossy image compression technique reduces the size of the image to a great extent, however the quality of the image being reproduced needs appreciation. The existing work presented, an improved polyomines lossless compression technique, which increases the quality of image at receiving end of the wireless communication by reducing the Peak to Signal Noise ratio and mean square error. In Wireless Sensor Networks, reducing transmission energy consumption is one of the important critical issues. In this paper, we propose a novel Energy Efficient High Quality Image Transmission scheme (EEHQIT) to achieve energy efficient image transmissions in WSNs. EEHQIT scheme is compelling due to its ability of saving individual power consumption over multiple sensors by spreading total transmission consumption. Individual packets describing an embedded wavelet-encoded image exhibit a significantly unequal contribution towards image quality. By leveraging this fact we develop a strategy of appropriately selecting the number of interactive sensors for each packet transmission in order to achieve the highest possible image quality with minimal transmission power consumption. Experimental results show that our proposed mechanism can provide about 2dB higher image quality under the same power budget compared with other transmission approach. Simulation results show up to 85 % reduction in the total power consumption achieved by using the proposed strategy.
Broadcasting Images in Wireless Networks
"... Server-initiated broadcast, compared to unicast transmission, presents excellent scalability to requests by multiple clients in wireless networks. In such networks, many mobile clients can have overlapping interests about the same visual information, thus image broadcasting is expected to find accep ..."
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Server-initiated broadcast, compared to unicast transmission, presents excellent scalability to requests by multiple clients in wireless networks. In such networks, many mobile clients can have overlapping interests about the same visual information, thus image broadcasting is expected to find acceptance in wireless broadcast networks (WBNs). In this paper we examine for the first time, to our knowledge, the problem of image broadcasting in WBNs. We propose a novel method that significantly reduces the time latency perceived by clients that request images. We also consider the issue of energy consumption, because portable devices operate with batteries. With experimental results we verify the superiority of the proposed method against existing methods from other domains. 1
