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Saliency detection is widely used in the fields of computer graphics and multimedia processing. Many computer graphics tasks, such as image segmentation, image labeling, and tracking, rely on the accurate generation of saliency maps. However, most current methods lack the ability to generate a fine boundary between the foreground and background while also providing a high recall rate. The saliency detection algorithm proposed in this paper is based on rectangular-wave spectrum analysis. In this method, we divide a given image into several regions, which are then convoluted using a pre-set rectangular-wave template. We determine the final saliency value by calculating the difference between a region and its adjacent regions, and its uniqueness compared with the entire image. Repeated tests using different data sets produced a high accuracy-recall rate. Moreover, the boundary in our saliency map is clear and fine. [ABSTRACT FROM AUTHOR]

With the explosive growth of multimedia data such as unlabeled images on the Web, image auto-annotation has been receiving increasing research interest. By automatically assigning a set of concepts to unlabeled images, image retrieval can be performed over labeled concepts. Most existing studies focus on the relations between images and concepts, and ignore the interdependencies between labeled concepts. In this paper, we propose a novel image auto-annotation model which utilizes the concept interdependency network to achieve better image auto-annotation. When a concept and its interdependent concepts have a high co-occurrence frequency in the training set, we consider boosting the chance of predicting this concept if there is strong visual evidence for the interdependent concepts in an unlabeled image. Additionally, we combine the global concept interdependency and the local concept interdependency to enhance the auto-annotation performance. Extensive experiments on Corel and IAPR datasets show that the proposed approach almost outperforms all existing methods. [ABSTRACT FROM AUTHOR]

Perceptual image hashing finds increasing attention in several multimedia security applications such as image identification/authentication, tamper detection, and watermarking. Robust feature extraction is the main challenge in hashing schemes. Local binary pattern (LBP) is a new feature which is due to its simplicity, discriminative power, computational efficiency, and robustness to illumination changes has been used in various image applications. In this paper, we propose a robust image hashing scheme using center-symmetric local binary patterns (CSLBP). In the proposed image hashing, CSLBP features are extracted from each non-overlapping block within the original gray-scale image. For each block, the final hash code is obtained by inner product of its CSLBP feature vector and a pseudorandom weight vector. Furthermore, singular value decomposition (SVD) is combined with CSLBP to introduce a more robust hashing method called SVD-CSLBP. Performances of the proposed hashing schemes are evaluated with two groups of popular applications in perceptual image hashing schemes: image identification and image authentication. Experimental results show that the proposed methods are robust to a wide range of distortions and attacks such as additive noise, blurring, brightness changes and JPEG compression. Moreover, the proposed methods have this capability to localize the tampering area, which is not possible in all hashing schemes. [ABSTRACT FROM AUTHOR]

Since mobile devices are becoming the primary platforms for many users who always roam around and access the cloud computing applications, the two concepts of mobile computing and cloud computing have emerged as a new widely accepted paradigm, mobile cloud computing. More and more users use cloud computing service and offload their local applications to the cloud. Unfortunately, developing mobile multimedia cloud services over heterogeneous wireless networks poses a challenge for service continuity. The degraded link quality and connection losses are likely to happen and these may affect service availability and service usage times in mobile cloud computing scenarios. To improve handoff quality and minimize utilized bandwidth, we propose a dual mode self-adaption handoff mechanism for multimedia services in mobile cloud computing environment. The new mechanism uses multipath transmission for media flows based on 'make before break' technology, and consists of the duplicate mode and the effective mode, which are changed according to the network condition. Analytic model and simulation are developed to investigate our new mechanism. The results demonstrate that the self-adaption handoff mechanism can realize seamless handoff for multimedia services in cloud, reduce the packet loss rate, as well as obtain a more efficient use of the scarce wireless bandwidth and the power of mobile devices. [ABSTRACT FROM AUTHOR]

Nowadays, multimedia communication has improved rapidly to allow people to communicate via the Internet. However, Internet users cannot communicate with each other unless they use the same chatting applications since each chatting application uses a certain signaling protocol to make the media call. The mapping architecture is a very critical issue since it solves the communication problems between any two protocols, as well as it enables people around the world to make a voice/video call even if they use different chatting applications. Providing the interoperability between different signaling protocols and multimedia applications takes the advantages of more than one protocol. Many mapping architectures have been proposed to ease exchanging the media between at least two users without facing any difficulties such as SIP-Jingle, IAX-RSW, H.323-MGCP, etc. However, the design of any of the existing mapping architectures has some weaknesses related to larger delay, time consuming, and security matters. The only way to overcome these problems is to propose an efficient mapping architecture. This paper proposed a new mapping architecture between Inter-Asterisk eXchange Protocol and Jingle Protocol. The proposed mapping architecture consists of IAX domain (IAX client, IAX server, IAX-to-Jingle gateway), and Jingle domain (Jingle client, Jingle server, Jingle-to-IAX gateway). The tasks of the translation gateways are represented by the URI conversion, media capability exchange, translator of call setup and teardown signals, and real time media transmission. [ABSTRACT FROM AUTHOR]

The research examined the impact of multimedia within the context of collaborative dyadic learning on students' performance in a third-grade history lesson, taking into consideration students' individual collaborative skills and dyad collaboration level. Participants were divided into a control group and an experimental group. The same learning materials were used for both groups, with the difference that the learning materials for the experimental group were delivered via a computer. Students in the control group worked in dyads with print materials, whereas students in the experimental group worked in dyads with a multimedia computer application. After considering the effects of learners' individual collaborative skills and dyad collaboration level, the results showed that the experimental group outperformed the control group exemplifying the positive influence of the dyadic collaboration around a computer on learning outcomes. [ABSTRACT FROM AUTHOR]

A Virtual itinerary for a real experience is an idea based on the virtual reproduction of the fresco of the Procession of the Magi painted by Benozzo Gozzoli in Palazzo Medici in Florence, in its original dimensions and spatial configuration, which was presented at the Digital Heritage International Congress in Granada in 2015. The installation stems from an approach to Cultural Heritage communication, that sets the visitor at the centre of the design process, as both recipient and agent of cultural transmission. In this vision, cognitive science and the concept of affordance play a crucial role in defining a multimedia set that promotes a primary mechanism of cognition embedded in the human beings, the perceptive-motory method to help visitors approach and understand art through a natural form of integrated aesthetic experience. [ABSTRACT FROM AUTHOR]

The article focuses on credibility in multimedia information retrieval with specific reference to video content credibility analysis. Topics discussed include an overview of general approaches used for assessing credibility in multimedia; work concerning the combination of textual and visual or audio features for automatic credibility estimation; and digital traces left in multimedia content from potential alterations.

Supporting high quality multimedia streaming on wireless devices poses several challenges compared to wired networks due to the high variance in network performance encountered in the mobile environment. Although rate adaptation is commonly used in multimedia applications to compensate for fluctuations in network performance, it is a reactive mechanism which is not aware of the frequently changing connectivity that may occur on mobile devices. This paper proposed a performance evaluation model for multimedia streaming applications that is aware of user mobility and network performance. We presented an example of mathematical solution to the model and demonstrated the functionality using common mobility and connectivity examples that may be found in an urban environment. The proposed model is evaluated based on this functionality and how it may be used to enhance application performance. [ABSTRACT FROM AUTHOR]

Given the increased attention to working with sound in multimodal and multimedia compositions, this essay summarizes current pedagogical research and scholarly conversations and then argues for more attention to the work of Canadian pianist and recording artist Glenn Gould, who was amongst the foremost artists of his time in critically thinking about and productively expanding the possibilities of sound recording and manipulation. Gould's own voice is a key feature of many of his recordings, and his brilliant radio documentaries serve as challenging models for what contemporary compositionists might do with sound and voice in the teaching of multimodal composing. Indeed, Gould anticipated so much contemporary media production, particularly a “do-it-yourself” aesthetic, from which we can still learn. Moreover, as Gould was primarily a musician and sound artist, his insights into and practice with working with sound and voice treat both sound and voice as their own material media; they are not, for Gould, metaphors and stand-ins for textual meaning making and, as such, his work might inform a multimodal compositional pedagogy that takes seriously the particular affordances of sound and voice. Attention to such work might help us consider what can be done with sound and voice in the production of multimedia “texts” where sound and voice act beyond the textual—not just as metaphors for textual meaning making, but as materialities with their own particular rhetorical and affective affordances and dimensions. [ABSTRACT FROM AUTHOR]

The IP Multimedia Subsystem (IMS) is considered as the common platform for providing a unified session control on top of various access network technologies for multimedia applications. At the same time, we are witnessing how wireless technologies become an integral part of our daily life, due to an increasing number of mobile multi-interface devices and the proliferation of wireless access networks. In this context the availability of transparent mobility management mechanisms is a key element to enhance user's quality of experience. On the other hand, context-awareness is a vital ingredient to allow mobile devices to make appropriate and timely mobility decisions. The benefits of using diverse context information (e.g., about the user, the service and the network) to manage mobility are twofold. First, the richer information is available, the more likely an intelligent decision can be taken. Second, it allows the network to assist the terminal to take mobility decisions, even up to the point of automatically initiating a mobility procedure if according to the context and user preferences this improves the user's quality of experience. In this paper we propose CATMISS, a solution to support context-aware mobility in IMS services. The solution is based on SIP signalling and makes mobility transparent for communication peers of mobile terminals. Two types of mobility are supported: a terminal changing of access network and a multimedia session being transferred from one terminal to another. The paper also describes the implementation of the solution and its deployment in an experimental platform. Experiments in this platform, with IPTV and videoconference services, are used to validate the proposal. [ABSTRACT FROM AUTHOR]

Spatio-temporal saliency detection has attracted lots of research interests due to its competitive performance on wide multimedia applications. For spatio-temporal saliency detection, existing bottom-up algorithms often over-simplify the fusion strategy, which results in the inferior performance than the human vision system. In this paper, a novel bottom-up spatio-temporal saliency model is proposed to improve the accuracy of attentional region estimation in videos through fully exploiting the merit of fusion. In order to represent the space constructed by several types of features such as location, appearance and temporal cues extracted from video, kernel regression in mixed feature spaces (KR-MFS) including three approximation entity-models is proposed. Using KR-MFS, a hybrid fusion strategy which considers the combination of spatial and temporal saliency of each individual unit and incorporates the impacts from the neighboring units is presented and embedded into the spatio-temporal saliency model. The proposed model has been evaluated on the publicly available dataset. Experimental results show that the proposed spatio-temporal saliency model can achieve better performance than the state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

This paper presents a number of insights into how a web interactive multimedia technology (WIM-T), an information and communication system, is currently being used by lecturers in the university context. WIM-T consists of several features such as chat, audio, and screen board. It provides students with the opportunity for real time collaboration. When used in a university blended learning environment, it enables immediate feedback between participants across a physical space. This paper discusses the findings conducted using an exploratory approach employing semi-structured interviews. This research contributes to the evaluation of new technology affordances and their effective use when designing subject deliveries. [ABSTRACT FROM AUTHOR]

Digital image watermarking is an important technique for the authentication of multimedia content and copyright protection. Conventional digital image watermarking techniques are often vulnerable to geometric distortions such as Rotation, Scaling, and Translation (RST). These distortions desynchronize the watermark information embedded in an image and thus disable watermark detection. To solve this problem, we propose an RST invariant domain watermarking technique based on fractional calculus. We have constructed a domain using Heaviside function of order alpha (HFOA). The HFOA models the signal as a polynomial for watermark embedding. The watermark is embedded in all the coefficients of the image. We have also constructed a fractional variance formula using fractional Gaussian field. A cross correlation method based on the fractional Gaussian field is used for watermark detection. Furthermore the proposed method enables blind watermark detection where the original image is not required during the watermark detection thereby making it more practical than non-blind watermarking techniques. Experimental results confirmed that the proposed technique has a high level of robustness. [ABSTRACT FROM AUTHOR]

On the demand of many applications, vehicle to vehicle (V2V) communications have attracted many researchers’ attentions. In the developments of traffic safety applications based on VANET, the dissemination delay is critical. The dissemination delay of safety messages in the form of text has been studied thoroughly. In contrast, the dissemination delays of video or audio safety messages are just emerging and there are still a lot of things to be done. Considering the poor communication environment of multimedia safety messages dissemination in V2V, the analysis of multimedia message dissemination delay has great significance in the traffic safety applications. By extending and integrating previous achievements of analyzing MAC access delay in video stream dissemination, we proposed a method for modeling the relay access delay of IEEE 802.11p in the multihop relay chain of VANETs. Simulation results showed that the cumulative distribution function, the expectation, and the standard deviation of the relay access delays can be calculated effectively. In addition, the impacts of the number of hops and the length of packets on the relay access delays have been properly evaluated. Our study would open these research issues for discussion, which will contribute to the design and implementation of traffic safety. [ABSTRACT FROM AUTHOR]

Camouflage effect evaluation and examination is an important procedure in digital camouflage pattern design as it is helpful in improving the objectivity and effectiveness thereof. Based on the human vision mechanism, we propose a new method, which creates a saliency map of the input image that can quantitatively evaluate the degree to which the target and surrounding background differ with respect to color brightness and space distribution. Then, we use this saliency map to evaluate the effect of camouflage design. Experimental results demonstrate that the saliency map is an effective approach for evaluating camouflage design. [ABSTRACT FROM AUTHOR]

In this paper, we propose a local and contextual controlled (LCC) fourth order partial differential equation (PDE) method for noise removal. First, a region based fourth order PDE is proposed, which conductance coefficients are chosen adaptively in terms of the domain type. Thus, the proposed method can preserve the advantages of forth order PDE and avoid leaving isolated black and white speckles. Furthermore, the region based fourth order PDE and two discontinuity measures are incorporated into a LCC fourth order PDE, where the joint use of the two discontinuity measures leads to a complementary effect for edge preservation. The proposed LCC fourth order PDE is tested on two typical images, including texture image and natural scene image, which show the superiority of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper we present an image retrieval system created within the research project MUCKE (Multimedia and User Credibility Knowledge Extraction), a CHIST-ERA research project where UAIC1 is one of the partners2. Our discussion in this work will focus mainly on components that are part of our image retrieval system proposed in MUCKE, and we present the work done by the UAIC group. MUCKE incorporates modules for processing multimedia content in different modes and languages (like English, French, German and Romanian) and UAIC is responsible with text processing tasks (for Romanian and English). One of the problems addressed by our work is related to search results diversification. In order to solve this problem, we first process the user queries in both languages and secondly, we create clusters of similar images. [ABSTRACT FROM AUTHOR]

A common task in visualization is to quickly find interesting items in large sets. When appropriate metadata is missing, automatic queries are impossible and users have to inspect all elements visually. We compared two fundamentally different, but obvious display modes for this task and investigated the difference with respect to effectiveness, efficiency, and satisfaction. The static mode is based on the page metaphor and presents successive pages with a static grid of items. The moving mode is based on the conveyor belt metaphor and lets a grid of items slide though the screen in a continuous flow. In our evaluation, we applied both modes to the common task of browsing images. We performed two experiments where 18 participants had to search for certain target images in a large image collection. The number of shown images per second (pace) was predefined in the first experiment, and under user control in the second one. We conclude that at a fixed pace, the mode has no significant impact on the recall. The perceived pace is generally slower for moving mode, which causes users to systematically choose for a faster real pace than in static mode at the cost of recall, keeping the average number of target images found per second equal for both modes. [ABSTRACT FROM PUBLISHER]

Over the past decades, today, and in the future, business contexts in software organizations and the common ways of developing software are changing dramatically. Formation of teams in distributed environments, virtual or not, calls for new ways of working across geographic, temporal, and cultural boundaries. This, however, also requires effective leadership approaches enabled through systems, processes, technology, and people. The authors pulled together this special issue to provide some ideas and strategies for practitioners and open questions for researchers. The Web extra at http://youtu.be/YxE6S6MM3Ws is an audio recording in which author IEEE Software Multimedia Editor Davide Falessi interviews Laurence Tratt and Adam Welc, guest editors of the magazine's September/October 2014 issue, about the field of programming languages. [ABSTRACT FROM PUBLISHER]

Forrest Shull writes his final column as IEEE Software editor in chief; outlining the magazine's accomplishments during his four-year tenure; introducing his successor, Diomidis Spinellis; and discussing the success of Software Experts Summit 2014 in Bangalore, India. The Web extra at http://youtu.be/yhBsX8OHqhY is a video overview of the multimedia content from past issues of IEEE Software and Computer magazines showing the endless possibilites that IEEE Computer Society multimedia affords. [ABSTRACT FROM PUBLISHER]

With the fast explosive rate of the amount of image data on the Internet, how to efficiently utilize them in the cross-media scenario becomes an urgent problem. Images are usually accompanied with contextual textual information. These two heterogeneous modalities are mutually reinforcing to make the Internet content more informative. In most cases, visual information can be regarded as an enhanced content of the textual document. To make image-to-image similarity being more consistent with document-to-document similarity, this paper proposes a method to learn image similarities according to the relations of the accompanied textual documents. More specifically, instead of using the static quantitative relations, rank-based learning procedure by employing structural SVM is adopted in this paper, and the ranking structure is established by comparing the relative relations of textual information. The learning results are in more accordance with the human's recognition. The proposed method in this paper can be used not only for the image-to-image retrieval, but also for cross-modality multimedia, where a query expansion framework is proposed to get more satisfactory results. Extensive experimental evaluations on large scale Internet dataset validate the performance of the proposed methods. [ABSTRACT FROM AUTHOR]

This study aims to investigate whether the English phonemic awareness of Thai grade one students can be enhanced through a multimedia CALL program while learning the English language through the whole word approach. It also explores Thai grade one students' views on improving phonemic awareness through a multimedia CALL program while learning the English language through the whole word approach. The research participants were 50 Thai grade one students who were classified into good, fair, and poor groups according to their English proficiency scores. The students in each group were divided equally into experimental and control groups: 25 students in the experimental group and 25 students in the control group. Then, three participants from each good, fair, and poor group were randomly selected to participate in a semi-structured interview. Three phonemic awareness tests were used to collect quantitative data obtained from the experimental and control groups. These tests were analyzed using descriptive statistics (Mean and SD) and t-test. In addition, a semi-structured interview was used to collect qualitative data with the data being analyzed using content analysis. The results of the study revealed that the experimental group made significantly greater gains in English phonemic awareness than the control group at the .001 level. Moreover, the finding of the qualitative data indicated that the students who were provided with the multimedia CALL program had positive views on enhancing phonemic awareness through this supportive tool while learning the English language through the whole word approach. [ABSTRACT FROM AUTHOR]

Most multimedia applications implement some kind of packet losses analysis mechanism to trigger self-adaptation actions. However, error recovery mechanisms such as ARQ variants avoid packet losses at IP level. Then, there appears an impact into the delay that may indeed result on application-level losses due to samples arriving later than the scheduled playout time. In most cases such degradations are not detected until they are so severe than even losses at IP level appear. We propose a lightweight method that achieves a finer grain estimation. We prove mathematically the capability of modified versions of statistics of delay to predict the error ratio of the wireless link and the load of the wired backhaul. After deducing also simplified heuristics for proposed method, we analyze their estimation capabilities and provide guidance for selecting appropriate parameters. Finally, we test and adjust the algorithm to an specific scenario including mobile video streaming and VoIP calls. [ABSTRACT FROM AUTHOR]