A survey of aesthetics-driven image recomposition

The advancement of digital photography and the popularity of photo sharing social media such as Instagram and Facebook have undoubtedly stimulated growing interest in aesthetics quality improvement. One aspect of photography that contributes to high quality photos is image composition; the spatial arrangement of photo subjects in the image frame. Professional photographers often apply a wealth of photographic composition rules, e.g., rule of thirds, visual balance and simplicity to capture compelling photos. In the recent years, aesthetics-driven recomposition that attempts to computationally modify the composition of an image to mimic a professional photo has started to receive considerable research interest. Researchers have proposed numerous recomposition techniques that utilize a single or a combination of multiple image operators, i.e., cropping, warping and patch rearrangement operators, to modify the composition of an image. In this paper, we present a survey on the state-of-the-arts aesthetic-driven image recomposition. We define the image recomposition problem, outline its objectives, and provide a comprehensive review of the existing image recompositoin techniques, together with a detailed analysis of the effectiveness of each technique in achieving the recomposition objectives. This survey is intended as a good reference for researchers interested in image recomposition.     

基于媒体独立切换并提供QoS保证的跨UMTS和WiMAX无线异构网络的网络切换方案

The rapid growth and innovation of the various mobile communication technologies have caused a change in the paradigm of internet access. Wireless technologies such as WiMAX, WiFi and UMTS/LTE networks have shown great potential in dominating the wireless access markets. The existence of various access technologies requires a means for seamless internetworking to provide anywhere, anytime services without interruption in the ongoing session, especially in multimedia applications with rigid Quality of Services (QoS) requirements. The IEEE 802.21 Media Independent Handover (MIH) working group was formed to develop a set of mechanisms under a standard framework with the capability to support migration of mobile users across heterogeneous networks. Therefore, the implementation of handover is extremely important in the heterogeneous network environment. In order to guarantee various QoS requirements during handover execution especially in multimedia applications, in this paper we propose a novel MIH-based capacity estimation algorithm to execute handover with QoS provision supporting both horizontal and vertical handovers across UMTS and WiMAX networks. Simulation shows that the proposed mechanism achieves lower call dropping rate (highest approximate 3% ) and higher system throughput (average 92% ) than the basic handover method does.     

Editorial: Big Data Innovation for Sustainable Cognitive Computing

Mobile Networks and Applications -     

Seamless handover between unicast and multicast multimedia streams

With the deployment of heterogeneous networks, mobile users are expecting ubiquitous connectivity when using applications. For bandwidth-intensive applications such as Interact Protocol Television （IPTV）, multimedia contents are typical- ly transmitted using a multicast delivery method due to its bandwidth efficiency. However, not all networks support multicasting. Multicasting alone could lead to service disruption when the users move from a multicast-capable network to a non-multicast network. In this paper, we propose a handover scheme called application layer seamless switching （ALSS） to provide smooth real-time multimedia delivery across unicast and multicast networks. ALSS adopts a soft handover to achieve seamless playback during the handover period. A real-time streaming testbed is implemented to investigate the overall handover performance, espe- cially the overlapping period where both network interfaces are receiving audio and video packets. Both the quality of service （QoS） and objective-mapped quality of experience （QoE） metrics are measured. Experimental results show that the overlapping period takes a minimum of 56 and 4 ms for multicast-to-unicast （M2U） and unicast-to-multicast （U2M） handover, respectively. The measured peak signal-to-noise ratio （PSNR） confirms that the frame-by-frame quality of the streamed video during the handover is at least 33 dB, which is categorized as good based on ITU-T recommendations. The estimated mean opinion score （MOS） in terms of video playback smoothness is also at a satisfactory level.     

Intelligence Framework Based Analysis of Spatial–Temporal Data with Compressive Sensing Using Wireless Sensor Networks

Wireless sensor networks produce immense sensor readings within a report interval to the sink. So transfer of information in a resource constrained wireless environment is difficult. Compressive sensing overcomes the resource constrains in wireless environment by exploiting sparsity in transfer with fewer measurement and recovery of original signal. In this research Intelligent Neighbor Aided Compressive Sensing (INACS) scheme is proposed for efficient data assembly in spatial and temporal correlated WSNs. Sparse Matrix has been formed with spatial and temporal coordinates for data transfer. In every sensing period, the sensor node just sends the readings within the sensing period to uniquely selected neighbour based on a correlation. The transmission period provides significant improvement with compressed data using INACS with the measurement matrix. Thus INACS provides reduction in number of transmission and higher reconstruction accuracy. INACS has been compared with Compressive wireless sensing for reduction in number of transmissions achieved. The time series analysis with INACS has been done to validate the simultaneous association between number of transmissions and time period.

     

Resource management for symmetrical applications over heterogeneous services in IEEE 802.16

Wireless Networks - Symmetrical applications are multimedia applications that require both uplink and downlink connectivity. The demands of symmetrical applications are expected to grow rapidly in...     

EAOMDV-MIMC: A Multipath Routing Protocol for Multi-Interface Multi-Channel Mobile Ad-Hoc Networks

Multipath routing has been proposed to improve performance of mobile ad-hoc networks (MANETs). However, due to: (1) nodes lacking of network interface and (2) route coupling, using multiple paths concurrently in conventional single channel MANETs rarely exhibit performance gain. To improve performance, an ad-hoc routing protocol (and its extension) that utilizes multiple homogeneous network interface is proposed in this paper. Unlike other related multi-channel routing protocols, channels are not assigned. Instead, nodes are allowed to make use of all available channels they are tuned to. In the base protocol, nodes estimate channel conditions by monitoring their network interface queues and distribute data packets to different channels and next-hops according to their conditions. In the extended protocol, estimated channel condition at a node is further propagated to neighboring nodes by piggybacking channel condition information in data packets. With overhearing, other nodes can retrieve this information to make better next-hop selections. Extensive simulation studies show that our protocol outperforms other related multi-channel routing protocols.     

An enhanced framework for providing multimedia broadcast/multicast service over heterogeneous networks

Multimedia broadcast multicast service （MBMS） with inherently low requirement for network resources has been proposed as a candidate solution for using such resources in a more efficient manner. On the other hand, the Next Generation Mobile Network （NGMN） combines multiple radio access technologies （RATs） to optimize overall network performance. Handover performance is becoming a vital indicator of the quality experience of mobile user equipment （UE）. In contrast to the conventional vertical handover issue, the problem we are facing is how to seamlessly transmit broadcast/multicast sessions among heterogeneous networks. In this paper, we propose a new network entity, media independent broadcast multicast service center （MIBM-SC）, to provide seamless handover for broadcast/multicast sessions over heterogeneous networks, by extensions and enhancements of MBMS and media independent information service （MIIS） architectures. Additionally, a network selection scheme and a cell transmission mode selection scheme are proposed for selecting the best target network and best transmission mode. Both schemes are based on a load-aware network capacity estimation algorithm. Simulation results show that the pro- posed approach has the capability to provide MBMS over heterogeneous networks, with improved handover performance in terms of packet loss rate, throughput, handover delay, cell load, bandwidth usage, and the peak signal-to-noise ratio （PSNR）.     

Resource Management and QoS Provisioning for Duplex Services in IEEE 802.16

Duplex services are multimedia services that requires good connectivity in both uplink and downlink such as VoIP, video conferencing and interactive gaming. A weak connection in either direction may cause degradation of performances and dissatisfaction of user experience. Most researchers do not consider this issue and treat resource allocations in uplink and downlink independently. For this reason, the conventional resource management schemes do not guarantee a good duplex connectivity. Generally, duplex schemes require some relation or information to be exchanged between uplink and downlink resource allocation processes. The existing duplex resource allocation schemes, however, have high complexity and do not adhere to the IEEE 802.16 standard. In this paper, we propose a duplex resource management scheme for IEEE 802.16 network to enhance the user experience and to improve the network performances. The proposed resource management scheme is a MAC layer function that co-relates the uplink and downlink allocation processes using a newly proposed duplex variable. Simulation studies show that the proposed scheme brings significant benefit to duplex services in the IEEE 802.16 networks and outperforms the conventional and existing schemes in terms of uplink and downlink transmission gap, QoS performances and fairness.