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When TV recommender systems perform well, number of interactions in which their users expressed positive feedback on the recommended content is expected to be greater than the number of negative ones. This is known as class imbalance and, paradoxically, it degrades the system performance by making the identification of the programs the user will dislike increasingly difficult. As the misclassification of the unwanted content is easily perceived by TV viewers, it should be avoided by all means. In this paper, a personalized TV program guide based on neural network is described. It is shown how class imbalance information can be exploited in learning the user preferences. This not only improves the system performance, but increases the user satisfaction as well.1 [ABSTRACT FROM AUTHOR]

Mobile broadcasting services are considered effective methods for emergency alert delivery. Terrestrial digital multimedia broadcasting (T-DMB) offers an emergency alert service called automatic emergency alert service (AEAS). However, the conventional AEAS is inefficient in the aspects of alert service channel, disabled T-DMB receiver, and location-based service. Therefore, this paper proposes a novel signaling method in order to overcome the drawbacks of the AEAS. The presented alert system exploits an additional alert channel, which is multiplexed with the conventional T-DMB channel. This paper also addresses the multiplexing approach, which effectively eliminates the interference between the additional alert channel and the TDMB channel. The simulation results confirm that the proposed signaling method effectively offers the emergency alert services in T-DMB1. [ABSTRACT FROM AUTHOR]

Existing emergency alert techniques of terrestrial-digital multimedia broadcasting (T-DMB) and digital audio broadcasting (DAB) can be executed only when the receivers are activated. To overcome the limitation of existing technique, a novel emergency wake-up alert system within a conventional T-DMB service network is proposed. The emergency wake-up alert signal is periodically generated by emergency transmission data unit (ETDU) and then transmitted through the conventional T-DMB/DAB station. After receiving the emergency wake-up alert signal, T-DMB/DAB receiver can be wake-up, activating and result in showing emergency broadcasting contents to people. To obtain frequency efficiency, the emergency wake-up alert signal is overlaid onto the conventional T-DMB frequency band using a direct sequence spread spectrum technique. To assess the performance of the developed ETDU, simple RF transmitter, test receiver and measurement equipment are used. The performance is checked with different values of emergency wake-up alert signal to T-DMB power ratio. The laboratory test results shows that the wake-up alert signal can be transmitted without degrading the existing T-DMB signal quality and can be detected at very low power emergency wakeup alert signal, e.g., as low emergency wake-up alert signal to T-DMB power ratio as -22.2dB. [ABSTRACT FROM PUBLISHER]

Over the air download is an important feature for terrestrial digital television systems. It provides a cheaper option for DTV receiver manufacturers to provide bug fixes and quality improvements to their products, allowing a shorter time to the market. This paper presents a mechanism proposal of an over the air download software update for the Brazilian system. This mechanism was specified considering the Brazilian DTV over the air download specifications, but it was extended considering efficiency, reliability and user transparency as requirements for software update. A proof of concept was implemented on a Linux based set-top box. The mechanism is divided into five main functional parts: download schedule, packets download, packets authentication, installation and error robustness. Some analyses were conducted upon the implementation considering the following criteria: download robustness and maximum downloading rate. [ABSTRACT FROM AUTHOR]

This paper presents a receive power analysis system for DTV broadcasting networks. This system measures the receive power and channel information simultaneously, analyzes the receive power of the measured multipath components and constructs 360 degree receive power profile by repeating analysis in all antenna directions. The proposed receive power analysis algorithm is proved by laboratory tests with two distributed translators. Field test results are briefly introduced and discussed for the evaluation of the proposed system. [ABSTRACT FROM AUTHOR]

In this paper it is described how interactive applications can be used to provide access services for people with disabilities in digital television. MHP (Multimedia Home Platform) is a standardized middleware to develop interactive applications in digital television. In this way, the interactive applications become tools for the provision of the access services. These features have been exploited in a research project to create a subtitle application for the deaf and hard of hearing people and an accessible electronic program guide for blind people. [ABSTRACT FROM AUTHOR]

Most of consumer electronic devices, including HDTV/IPTV, multimedia teleconference systems, on-line game stations, and HiFi-audio systems, are expected to be connected through WiFi WLANs in home/office networks. Especially, the realtime multimedia applications are requiring guaranteed bandwidth to provide guaranteed QoS/QoE. As a consequence, correct estimation of the available bandwidth in overlapped WiFi WLANs in home/office network environments is one of the essential functions for efficient provisioning of Qos-guaranteed realtime multimedia applications and optimized network resource utilizations in future internet. in this paper, we propose a cognitive passive estimation of the available bandwidth (cPEAB) by correct measurements of i) the proportion of waiting and backoff delay, ii) packet collision and packet error probability, iii) acknowledgement delay, iv) channel idle time compared to measurement period, and v) traffic from hidden/exposed terminals. Using a series of experiments, we found that the proposed scheme estimates the available bandwidth more accurately compared with other schemes. [ABSTRACT FROM AUTHOR]

Consumers are flooded with amounts of discount coupons, oftentimes for products that are far from their interests. This marketing custom is already rising on the Internet and is imminent in Digital TV, where the massive sending of coupons leads to their devaluation and consumer indifference. The computing capabilities of these media permit to alleviate this problem by means of recommender systems, which are very useful tools in application domains that suffer from information overload. However, current recommender systems overlook the diversity of products and services available in the market, which gives rise to forming fake neighborhoods in collaborative filtering strategies. In this paper, we apply semantic reasoning techniques to avoid such fake neighborhoods and, thereby, improve the recommendation process. Furthermore, taking advantage of the Digital TV medium, we propose matching the recommended coupons to TV contents semantically related with them, in order to increase their redemption. [ABSTRACT FROM AUTHOR]

Interference to DTV reception from signals in the 88-108 MHz FM broadcast band has been observed since the end of analog TV broadcasting in June, 2009. This interference is generated in the front-end (tuner) of the affected receiver. This paper describes the non-linear mechanisms in the receiver by which FMI to DTV reception takes place. The author has tested 15 models of NTIA approved DTV down-converters measuring the increase in DTV received signal power required as a function of the power of local off-air FM signals in his laboratory. He has also tested "amplified indoor antennas" and found their performance was seriously impaired by FMI. This work was carried out as unsponsored research. [ABSTRACT FROM AUTHOR]

In these days, multi-touch technology becomes an important interface in various environments. However, most of multi-touch systems have a characteristic of low applicability so that it is difficult to apply to diverse applications. In this paper, we compare the main three methods of multi-touch systems, and analyze the pros and cons of these systems. By considering applicability and economical efficiency, we propose an infrared LED based system suitable to be used in multi users. To solve coordinate recognition problems in collinear in a 2-dimensional bi-axial coordinate system, we design a 2-dimensional tri-axial coordinate multi- touch system using infrared LEDs. The comparing result between two systems shows that the recognition rate in the bi- axial coordinate system is 49 percent and the recognition rate in the tri-axial coordinate system is 99 percent. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel frame reordering scheme and a high speed VLSI architecture of full search variable block size motion estimator(VBSME) supporting multiple reference frames. In the proposed architecture, four current macro bocks are concurrently compared with a single search window (SW) of the reference frame to find the best matched block. By scheduling the order of the reference frame in pipeline, the proposed architecture can reduce the memory bandwidth and the execution time. Also, the proposed architecture can fully reuse the over- lapped searching area in the horizontal direction to reduce the memory bandwidth and obtain 100% hardware utilization of the frame level by using the meander-like scan and the method of MB-level data reuse. Then, 71.73% of local memory size and 69.34% of system memory bandwidth were saved compared with non pipelined-multiple reference frame motion estimation (NP-MRFME). Under an operating frequency of 112.32MHz, the architecture can support the real-time processing of 1280×720 picture size at 30fps with the search area of [-16, +15]. [ABSTRACT FROM AUTHOR]

In this paper, we propose a parameter optimization method for RIO (RED (Random Early Detection) with In and Out) scheme for Assured Service (AS) in Differentiated Services (DiffServ). The RIO was proposed to use to ensure the expected capacity specified by the traffic profile. However, in order to optimize the QoS (Quality of Service) performance for the AS in DiffServ in terms of maximum tolerable latency, link utilization, etc., the RIO policy should be operated considerately. Therefore, in order to guarantee the maximum delay for each AS subclass in DiffServ, the proposed scheme differentiates the assigned bandwidth to each subclass efficiently. In addition, we propose a configuration method for the RIO and the admission control criterion considering the allocated bandwidth to each subclass and the corresponding buffer size to increase the throughput for the In-profile traffic and the link utilization. Simulation results show that the capacity for the AS can be effectively estimated by using the proposed method and the throughput for the In-profile traffic and the link utilization can be improved remarkably by applying the optimized RIO parameter set. [ABSTRACT FROM AUTHOR]

The emergence of three dimensional (3D) video applications, based on Depth Image Based Rendering (DIBR) has brought up more requirements of bandwidth, due to the need of depth information. This additional bandwidth requirement need to be tackled to enable the widespread of 3D video applications based on DIBR. Exploiting visual correlations between the color image and the depth image, in depth image coding, will reduce the requirement of high bandwidth required to transmit the additional depth information. In this paper, an object based depth image coding technique is presented which is suitable for low bit rate 3D-TV applications that are based on Depth Image Based Rendering. The proposed method achieves at most 50% bit rate reduction at low bit rates. [ABSTRACT FROM AUTHOR]

An efficient mobile video streaming system needs to cope with unstable network bandwidth and limited battery life. We propose a novel streaming system which jointly considers picture quality, bit-rate and energy consumption. Reducing the spatial resolution of a video stream adaptively proves to be more efficient in terms of picture quality and energy consumption than conventional rate control using only adjustment of quantization parameter. We apply the same scheme to scalable coding for large-scale mobile video streaming. This extends the adaptation of an SVC stream to lower bit-rates, while maintaining temporal stability. Our approach has been shown to improve picture quality by approximately 0.5dB in low bit-rate conditions, and also reduces energy consumption by more than 50% compared to conventional video streaming. [ABSTRACT FROM AUTHOR]

This paper presents the novel development of an embedded system that aims at digital TV content recommendation based on descriptive metadata collected from versatile sources. The described system comprises a user profiling subsystem identifying user preferences and a user agent subsystem performing content rating. TV content items are ranked using a combined multimodal approach integrating classification-based and keyword-based similarity predictions so that a user is presented with a limited subset of relevant content. Observable user behaviors are discussed as instrumental in user profiling and a formula is provided for implicitly estimating the degree of user appreciation of content. A new relation-based similarity measure is suggested to improve categorized content rating precision. Experimental results show that our system can recommend desired content to users with significant amount of accuracy. [ABSTRACT FROM AUTHOR]

Among the most promising applications provided by interactive Digital Television Systems (iDTV) are the ones that enable TV-Sets to work as the central processing unit of a house. This is supported by the extending of iDTV common functionalities making use of its processing power not only to deal with image and audio but also to execute interactive software applications. This paper proposes a new infrastructure that allows the exchange of data from the iDTV to Home Automation devices, such as sensors, mobile devices, and so on. The integration process among the involved technologies as well as each element in the proposed infrastructure is described in details. This model is supported by Open Services Gateway initiative (OSGi), as a framework for networked devices, and the Brazilian reference middleware, Ginga. Thus it is possible to use devices services in OSGi-based Home Networks, through the Digital TV. in order to prove the model functionalities, we created validating scenarios of service management involving iDTV interaction with mobile phones and electronic sensor devices using WiFi and Bluetooth technologies. [ABSTRACT FROM AUTHOR]

The delivery of digital multimedia data over wireless networks enables many useful consumer applications such as home entertainment. However, there are many performance-related issues associated with the delivery of time-sensitive multimedia content over current wireless communication systems such as those using the IEEE 802.11 standards. Among the most significant issues are the high error rates, because of the media characteristics, and signal attenuation with distance. In this paper, we present a robust digital baseband processor using hybrid channel estimation for wireless home audio--video receivers operating on an IEEE 802.11g wireless local area network (WLAN). The proposed hybrid channel estimation is a combined decision-directed and pilot-assisted method for perfect channel state information (CSI). Experimental results show that the proposed method increases system performance by about 3 dB over the least squares (LS) scheme at 100-ns root mean square (RMS) delay. [ABSTRACT FROM AUTHOR]

In this paper a distributed object-oriented framework (DOBS, Distributed Object Based Services) for home service design is presented. This framework eases the development of advanced services able to run in a variety of devices ranging from tiny wireless sensors to powerful multimedia servers. Special emphasis will be made on DOBS main features, its core components, the offered common services and the supporting tools developed to allow users and manufacturers to easily build advanced DOBS compliant services. [ABSTRACT FROM AUTHOR]

Digital Video Broadcasting for Handheld (DVB-H) is one of the wireless technologies that provide modern digital television services. The main objective of this paper is to propose a method to evaluate the performance of mobile rebroadcaster in terms of symbol error rate, taking into account antenna effects and the Angle of Arrival statistics. A correction factor is derived from concepts as the Mean Effective Gain, which joined to a closed-form expression for the symbol error probability, allows predictions about the antenna impact on the broadcaster. The quantitative evaluation of the analysis identifies an important SNR reduction from 4 dB to 10 dB, depending on the environment. [ABSTRACT FROM AUTHOR]

This paper proposes a novel LDPC (Low-Density Parity Check) decoder architecture to increase throughput for DVB-S2, a second generation standard of ETSI (European Telecommunications Standards Institute) for European satellite digital video broadcasting system, which is employed in European digital TVs. The proposed architecture clusters nodes of a Tanner graph into node groups utilizing the properties of IRA (Irregular Repeat-Accumulate) LDPC codes. Functional modules, which perform calculations for node groups, read and store messages at predetermined local memory banks. The memory banks are designed to avoid memory conflicts by differentiating read and store timings. Hence, throughput of the proposed architecture can be increased. Experimental results show that the throughput of the proposed architecture is increased by 104% ~ 479%, when compared to previous architectures. [ABSTRACT FROM AUTHOR]

In the advanced generalized conservative staircase (AGCS) method, the video segments are arranged in groups. The first group contains first segment, second group contains next two segments, and pth group (p>2) contains 3ª2P-3 number of segments starting with kth segment S,. where k=3ª2p-3+1. Each segment of pth group (p>2) is divided into 3ª2P-3ª+mp+mp-1 subsegments, where mp determines the number of subsegments of a segment in pth group that are transmitted in a time slot. The subsegments are arranged in nip disjoint sets. The first set consists of subsegments Sq+i,2,..., Sq+i,q, Sq+i,q, where q 3ª2P-3 1⩽i⩽q, and zth set (1p) consists of subsegments Sq+i,qª(z-1)+z-1, Sq+i,qª(z-1)+z+1 Sq+i,qªz+z-1. In the AGCS method, an upper bound on mp has been derived to provide continuous data. If larger value of mp than its upper bound is taken, then the method will not provide continuous data. But, increasing the value of mp decreases the bandwidth requirement, which in turn gives better method. In this paper, we discuss a scheme that removes the bound on mp and still provides the continuous video data to users. [ABSTRACT FROM AUTHOR]

Artificial bandwidth extension methods aim to improve the quality and intelligibility of narrow band telephone speech by adding new, artificially generated spectral content to the highband of the received voice signal. The development cycle of an artificial bandwidth extension method from the initial idea to the implementation in a mobile terminal is discussed in this paper. Developing the algorithm in the Matlab environment was the first step in the process. The method was then evaluated informal listening tests and simulations to verify its performance in different scenarios. Finally, the utilization of this technology in a product included its DSP implementation combined with the acoustical design of the user terminal. [ABSTRACT FROM AUTHOR]

With the popularization of digital TV and Internet Protocol TV (IPTV), more digital programs are being produced. In order to find the programs users want to watch, it is sometimes difficult and time-consuming for them to read the programs' information provided by Electronic Program Guide (EPG). Therefore, the next generation EPG composed of content search, content recommendation, and content management is expected to help users quickly, and easily find programs they are interested in. In content recommendation, this study proposes a Community-based Program Recommendation (CPR) for the next generation EPG. It analyzes and categorizes users with similar viewing habits into one community, then recommends programs to users to help them quickly find the programs they want to watch. The results show that this method can provide good precision and convenience to users. [ABSTRACT FROM AUTHOR]

Streaming high quality audio/video (A V) from home media sources to TV sets and audio speakers over a wireless local area network (WLAN) is a challenging problem because of the fluctuating bandwidth caused by interference and fading. Retransmission and data buffering, as common techniques in data transfer over error-prone channels, are not adequate for delay sensitive applications such as high quality audio streaming. Our approach is to adjust the audio data rate dynamically in order to improve the perceptual quality of audio according to wireless channel quality. In this paper we specifically focus on robust audio streaming over short range wireless channels. The major strength of the proposed algorithm is in its ability to match the source and channel coding parameters to the given channel conditions, thus providing better quality and lower latency of audio in home networking. [ABSTRACT FROM AUTHOR]

This paper introduces a promising property in which the transmitter of an OFDM system can utilize an N-point IFFT operation to build the time-domain symbols of a KN-point IFFT operation. Based on this property, we propose a flexible OFDM structure. This structure will support uplink applications which include many transmitters using different numbers of subcarriers and one receiver with just one IFFT/FFT module with the subcarriers of least common multiple (LCM) for the number of subcarriers of all the transmitters. Therefore it reduces the design complexities of the receiver and increases the compatible characteristics for consumer electronics (CE). Compared with the original OFDM system, the proposed system improves the performance of the packet error ratio (PER) and the bit error ratio (BER) performance by using the appropriate K. In addition, the proposed structure can be designed to enlarge the bandwidth efficiency of the system and improve the performance of channel estimation compared, with the OFDM/TDM system. [ABSTRACT FROM AUTHOR]

Multimedia services including IPTV require huge multimedia data transmission on the internet. In order to improve a throughput of data transmission, network coding has been proposed to use network bandwidth (=throughput) efficiently with error free channel assumption. However, when the channel is not error free, network coding may not increase the throughput. In this case, effective erasure recovery codes such as Raptor codes have to be used with the network coding. We present the advantage of Raptor codes combined with network coding for high throughput multimedia data transmission services like IPTV. For the applications allowing retransmission, Hybrid-ARQ combined with network coding is also considered. [ABSTRACT FROM AUTHOR]

As the demand for real-time IP media transport over multi-point delivery environments increases, it is essential to monitor the time-varying status of both network metrics (i.e., delay, jitter, and loss) and system metrics (i.e., CPU and memory utilization). In this paper, we propose and implement a new monitoring system for the high-quality real-time media delivery over multicast- enabled network. It monitors the time-varying conditions of both the multicast network and the node system. When the media performance degrades, the proposed monitoring system attempts to pinpoint the cause of performance degradation to improve the end-to-end performance. The experimental results show that we can effectively infer the cause of performance degradation using the implemented prototype of the proposed monitoring system. [ABSTRACT FROM AUTHOR]

In this paper, we present an FPGA-based fast image warping method by applying data parallelization schemes. The parallelization of accesses to pixels relieves not only latency problem of the warping, but also bandwidth requirements of off-chip memory. The LUT data parallelization scheme efficiently replaces parallel arithmetic operations with neither of increased memory size for LUT entries nor clock frequency. Two implementations with different characteristics prove the effectiveness and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

The usage of podcasting for all kind of media files in the Internet has become very popular. A part of its strength lies in its simplicity. However, the success of such a technology proves not only the demand for structured data but also produces new problems of networking costs for broadcasters. Media devices of the future will be able to access content either from digital broadcast networks or through the Internet infrastructure. In order to manage and present this multifaceted material to the user, common metadata and procedures are needed. This contribution will give a survey of the standards and methods provided for digital broadcasting and cellular systems as DAB/DMB, HD RadioTM, DVB, UMTS and explore their ability to interface with on-demand content provided in the Internet. Two implementations for digital radio and TV will show how such a linkage of linear content with on-demand content can be presented to the user. [ABSTRACT FROM AUTHOR]

This paper presents the design and implementation of a software (SW)-based receiver running on a single digital signal processor (DSP) for terrestrial digital multimedia broadcasting (TDMB). Implementing the functions of the physical layer such as synchronization and channel decoding as well as codec decoders for a TDMB receiver in software running a DPS raises numerous design and implementation issues. We present solutions to these issues including an efficient software receiver structure, efficient algorithms with low complexity, real-time scheduling, reduction of the execution cycle number, and data transfer and communication between function blocks in the receiver, with a focus on the physical layer. The SW-based TDMB receiver developed in the present work can change and upgrade its functions and adapt to new standards. The performance of the implemented receiver was verified through successful decoding of live audio and video signals. [ABSTRACT FROM AUTHOR]

When using a finite DTV stream, discontinuity phenomena, such as a black or paused screen in the case of video and irregular or popping sounds in the case of audio, are generally experienced at the loop-back point. As the transmission time of the transport stream (TS) is commonly longer than the presentation time of video sequences, this causes an element stream (ES) buffer underflow at the loop-back point of the TS. Therefore, this paper proposes a time-matching multiplexing method for endless loop-back playing to resolve the discontinuity problem. Equations are developed to match the play times of the source, TS, and ES in consideration of the special TS transmission rate. In addition, new multiplexing methods are used to generate a TS to match the minimum matching time (MMT). Experimental results show that the MMT stream effectively eliminates any discontinuities. [ABSTRACT FROM AUTHOR]

In this paper, we propose a fine edge-preserving image interpolation algorithm based on local gradient features. The proposed algorithm determines the edge direction using horizontal and vertical gradient operators, and then the edge direction is conceptually changed to the position between adjacent pixels. Since our algorithm is independent of interpolation kernels, various conventional kernels can be implemented. Experimental results show that the proposed methods can preserve clear edges and reduce blurring artifacts. [ABSTRACT FROM AUTHOR]

Digital television/terrestrial multimedia broad- casting (DTMB), announced as the Chinese digital television terrestrial broadcasting (DTTB) standard, uses pseudo-noise (PN) sequence as guard interval (GI) and the training sequence for both multi- and single-carrier block transmissions. The conventional channel estimation methods can be performed through either the subtraction of the PN sequence or the cancellation of residual inter-symbol interference (181). In this paper, a novel iterative method is introduced to estimate the overlapping part of PN sequence, meanwhile the channel impulse response (CIR) estimation can be obtained and updated via the reconstruction of the PN sequence in an iterative manner. Simulations show that the proposed algorithm can effectively reduce the ISI and improve the symbol error rata (SER) of DTMB system over slow- varying broadcasting multipath channel even with long delay spread. In practice, the proposed algorithm can be applied to the DTMB receiver-chip directly with low-complexity cost. [ABSTRACT FROM AUTHOR]

In this paper, we present the interactive data broadcasting service in T-DMB using middleware technology, which is known as T-DMB MATE (Mobile Application Terminal Environment). The T-DMB MATE defines a number of API to provide various applications with high-level functionalities for interactive data service, supporting a running environment of the applications. Specially, this paper introduces an implementation of T-DMB MATE receiver and some kinds of applications based on the designed T-DMB MATE service. Finally, the effectiveness of proposed service was verified by implementing the receiver and a variety of applications. [ABSTRACT FROM AUTHOR]

This paper describes hardware-based IP data reassembly processor for multimedia STB (Set-Top-Box) compatible with DVB-RCS. The conventional IP reassembly scheme is based on software processing of multimedia STB. As the transmission rate increases in order to support the broadband multimedia data services, the CPU load of multimedia STB is increased and reassembly performance is degraded. To provide smooth and flexible broadband multimedia data services, we proposed hardware based high speed reassembly processor. It has been tested and confirmed to meet required functions and performances. [ABSTRACT FROM AUTHOR]

The staircase scheme requires minimum buffer storage among all the broadcasting schemes that provides the video services. It however does not always deliver the video data to users in time. This problem has been overcome in the conservative staircase scheme, but the scheme requires more resources especially the buffer storage. In the conservative staircase scheme, the video is divided into segments depending upon the number of video channels allocated to it by the video server. The bandwidth of a video channel is equal to the viewing rate of the video. The segments are further divided into subsegments and the video channels into subchannels in such a way that a subchannel transmits all the subsegments of a single segment. In this paper, we propose a new mechanism for utilizing the buffer storage efficiently in the conservative staircase scheme. In the proposed scheme, the segments transmitted by each of the video channels are arranged in decreasing order of their indices. By doing this, the data of the segments can be delayed without failing their availability to the users in time. By delaying downloading of the data, only that data is stored in the buffer storage at the user's site that is needed immediately and in very near future. This scheme not only provides the video services using less storage space but also requires less disk transfer rate as compared to the conservative staircase scheme. Furthermore, the complexity of this scheme is much less than that of the conservative staircase scheme because it does not require the segments to be divided into subsegments and the video channels into subchannels. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new search algorithm that reduces the memory, bandwidth required for finding active edges in Open VG rendering. It simultaneously prepares an active edge table for each scanline so that one edge may be stored in several active edge tables, which depends on the lifetime of each edge. It also gives us another benefit so that we can implement the multiple scanline filling in parallel for performance improvement. Experimental results show the external memory accesses of the proposed algorithm can be substantially reduced and the performance of the proposed dual-scanline filling rendering architecture can be significantly increased, especially for high-quality images. We implemented an Open VG accelerator using the dual-scanline filling rendering with one-poly four-metal 0.18-µm CMOS technology, which requires about 350K gates and operates at 100 MHz. [ABSTRACT FROM AUTHOR]

Home networks are becoming ubiquitous. Multimedia is a primary home network application that is challenging bandwidth capabilities with respect to QoS and also creating issues regarding authorized access to the home network and its digital content. To deal with these issues, this study presents an embedded QoS-aware residential gateway (EmQRG) in the home network which classifies forwarded traffic for optimal use of bounded network bandwidth resources and, instead of traditional password methodology, requires bimodal biometric recognition of users. A laboratory EmQRG testbed with bimodal biometric recognition system (BBRS) is implemented via class-based queuing (CBQ) bandwidth management in a 3-PC network including a real DiffServ-capable CBQ-capable router, CCD camera and optical fingerprint reader. Novel computational methods are used for face and fingerprint analysis and recognition. It is confirmed that combining two biometric modalities improves performance, particularly for the false acceptance rate (FAR) that is considered the most serious home security problem. Experimental results demonstrate efficiency and robustness of both the EmQRG and the BBRS. [ABSTRACT FROM AUTHOR]

This paper discusses a link layer protocol that enhances performance of the Transmission Control Protocol (TCP) over a last-hop wireless network (LHWN) to make it more suitable for delivery of a live video with a short playout deadline. The presented protocol provides preference control of the transmission of video data within the network and it maximizes network goodput (the successfully transmitted amount of useful video data) by maximizing reliability of transmission for a given playout deadline and a varying digital bandwidth. The protocol makes use of the skip function in the TCP receiver to maximize end-to-end throughput of the connection at the expense of reducing full reliability. It can be implemented in a wireless access point to improve quality of the received live video over an Internet connection to an office or home. The main ideas of the protocol are. hide packet losses from the sender by performing local retransmissions based on the information from the video application and according to a certain scheduling policy, drop stale segments before they arrive at the receiver and prevent end-to-end retransmissions of segments received by the access point. The performance of the TCP Reno protocol in combination with both the presented protocol and the skip function in the receiver is compared against the performance of TCP Reno, the TCP-Real-Time Mode (RTM) protocol, TCP Reno in combination with the Snoop protocol and TCP-RTM in combination with Snoop. The results of simulations show improvement of network goodput across a wide range of packet-error rates. [ABSTRACT FROM AUTHOR]

If interactive Digital Television (iDTV) and Residential Service Gateway (RG) could converge, i.e. to share services and resources, add-on values could be created. We propose a wrapper (adaptor) and a broker model with cooperative interfaces and a communication mechanism to support the collaboration between instances of iDTV and RG. The proposed approach has a higher extensibility, and it is better suited to an object oriented approach. Our experimental target iDTV middleware is DVB/MHP Java Profile, and the Residential Gateway middleware is the Open Service Gateway initiative (OSGi). The MHP and OSGi are implemented on a single Java Virtual Machine. The MHP application manager is wrapped as a bundle, and a broker is responsible for communication between the MHP and the OSGi. Hence, application developers do not need to know beforehand which services are on the iDTV or RG, and services are discovered dynamically. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present the concept for the development of an entirely speech-based user interface for a digital radio in combination with the possibility to specifically search for audio and data content. On the basis of a Digital Audio Broadcasting DAB device the embedded system utilizes a multichannel receiver with the possibility of simultaneously monitoring a variety of information sources with the purpose to generate spoken replies to verbal user requests. Furthermore, the system embraces an audio repository storing speech-based content elements to diminish the volatile property of broadcast content and to enable a memory function.' [ABSTRACT FROM AUTHOR]

This paper describes a highly efficient transmission system for digital broadcasting redistribution services using IPTV technique. For basic requirements of IF redistribution services, we propose highly efficient compression scheme, SI (Service Information) multicasting scheme and a robust IF transmission scheme. A prototype system is implemented based on the proposed scheme, and its performance is evaluated. [ABSTRACT FROM AUTHOR]

In recent years, advanced data broadcasting services, which provide viewers with multimedia data on digital television, have drawn growing interest. At the same time, there is file-sharing peer-to-peer service on digital television field. However, few studies pay attention to their convergence that is data broadcasting can help peer-to-peer service. This paper studies file-sharing peer-to-peer application among set -top boxes in bidirectional HFC networks. The study proposes the new architecture that using data carousel completes search work in peer-to-peer system. Finally, the experiment demonstrates advantages of the proposed strategy in hybrid peer-to-peer system. [ABSTRACT FROM AUTHOR]

The efficiency of H.264 video compression together with the wide use of MPEG-2 today necessitates transcoding between these two technologies. The combination of bandwidth efficient technology such as H.264 and the widely deployed MPEG-2 allows for innovative video delivery services that can exploit both these technologies. Using H.264 for video delivery and MPEG-2 for playback on the end user equipment fully leverages the benefits of these technologies. This architecture requires transcoding H.264 video delivered over networks to MPEG-2 format for playback on the end- user device. We present algorithms for transcoding H.264 to MPEG-2 and evaluate the performance of these algorithms. The performance is compared with a baseline transcoder with a full decoding stage and a full encoding stage. The proposed algorithms reduce the complexity by reducing the search space for motion estimation. The results show that the proposed algorithms reduce the motion estimation complexity by over 80% with a negligible loss in PSNR. [ABSTRACT FROM AUTHOR]

Current satellite digital broadcasting transmission system "ISDB-S " employs digital modulation schemes, BPSK, QPSK, and 8PSK combined with a concatenated code consists of convolution code and Reed- Solomon code. While, in recent years, transmission systems adopted LDPC codes have been developed. Multi-level digital modulation schemes combined with LDPC codes can achieve more efficient transmission. In this paper, we propose a new transmission system employed LDPC, multi-level modulation and advanced TMCC signal. [ABSTRACT FROM AUTHOR]

With the development of IEEE 802.11 MAC (Medium Access Control) protocols, efficient utilization of wireless local area networks (WLANs) has become a very important issue. In typical IEEE 802.1] networks, the association between mobile users (MUs) and access point (AP) is based on the signal strength information. As a result, it often results in the extremely unfair bandwidth allocation among MUs. In this paper, we propose a distributed association algorithm to achieve load balancing among the APs. The proposed algorithm gradually balances the AP loads for the available multiple bit rate choices in a distributed manner. We analyze the stability and overhead of the proposed algorithm, and show the improvement of the fairness via computer simulation. Additionally, we have implemented a prototype on a testbed to prove its feasibility. [ABSTRACT FROM AUTHOR]

Despite the ,nanr advantages in digital Th users get i,tto difliculties when titer navigate channels to fin their preferred programs. This is because the number channels is much more and the c/tunnel zapping speed i much slower i,t digital TV than in analog one. There hay been many efforts to reduce the channel zapping debt' I dj~gita/ TV However, the reduction of channel zapping dela is limited by the Itatu,-e of digital TVsvste,n. In this paper. w aropose alternative approaches that enable the efficien channel navigation in digital TV. The first approach is to hid a channel change delay. T/tis apptvarh is helpful when t/, user wants to navigate channels hr pressi,tg up/down button in a full screen ,ttode. The second approac/t is to show multt channel mosaic screen. This is helpful when the user wants navigate channels by pressing finn-tray l,uttons whil watching preview videos. In this paper, we propose a Circula Buffering Algorithm ((`BA) and show that, with help of th CB.4, hiding channel change delay and n,t,lti-chatttte/ ntosai tcreen con he foasible in the system with limited resource,~ Simulation results shotr that the proposed methods gire user high satisfaction in channel navigation. [ABSTRACT FROM AUTHOR]

Despite the ,nanr advantages in digital Th users get i,tto difliculties when titer navigate channels to fin their preferred programs. This is because the number channels is much more and the c/tunnel zapping speed i much slower i,t digital TV than in analog one. There hay been many efforts to reduce the channel zapping debt' I dj~gita/ TV However, the reduction of channel zapping dela is limited by the Itatu,-e of digital TVsvste,n. In this paper. w aropose alternative approaches that enable the efficien channel navigation in digital TV. The first approach is to hid a channel change delay. T/tis apptvarh is helpful when t/, user wants to navigate channels hr pressi,tg up/down button in a full screen ,ttode. The second approac/t is to show multt channel mosaic screen. This is helpful when the user wants navigate channels by pressing finn-tray l,uttons whil watching preview videos. In this paper, we propose a Circula Buffering Algorithm ((`BA) and show that, with help of th CB.4, hiding channel change delay and n,t,lti-chatttte/ ntosai tcreen con he foasible in the system with limited resource,~ Simulation results shotr that the proposed methods gire user high satisfaction in channel navigation. [ABSTRACT FROM AUTHOR]

The channel bandwidth variation and the disconnection during handoff are the most critical problems which degrade the video quality in wireless video streaming. To cope with these problems, we propose an efficient video streaming method in this paper, which does not only dynamically adjust the video transmission rate based on the channel bandwidth, but also minimize the error propagation during handoff Firstly, the channel bandwidth of the mobile worldwide interoperability for microwave access, called WiMAX~ is estimated by analyzing channel parameters including the carrier to interference and noise ratio (CINR) and the handoff is detected by using the handoff occurrence message (HuM). Secondly, the streaming server adjusts the next transmission rate according to the estimated channel bandwidth to avoid the network congestion and performs the intra refresh method that inserts an intra frame (I-frame) right after handoff by using the HOM to reduce the error propagation effectively. Experimental results indicate that the proposed method can improve the performance of the video streaming over mobile WiMAX'. [ABSTRACT FROM AUTHOR]

This paper presents an ejJicient discrete-time bandpass sigma-delta (.ZA) modulator and digital in-phase /quadrature (I/Q) demodulator for multistandard wireless applications. The proposed bandpass IA modulator provides higher speed using advanced switched-capacitor resonators which are faster than the conventional ones. The test chip has been implemented in a 0.18 jim CMOS process and occupied with the active chip area of 0.16 mm2. The power consumption of the fabricated chip is 2.34 mWwith a 1.8 Vsupply voltage. The measured peak signal-to-noise ratios (SNR) are 34 dBfor 1.536 MHz (T-DMB), 26 dB for 5 MHz (UMTS), and 20 dB for 10MHz (WiBro) bandwidths, respectively. This paper also covers the simple and robust digital I/Q demodulator which has been realized using a field programmable gate array (FPGA) for digital signal processing'. [ABSTRACT FROM AUTHOR]