Abstract: Visual information retrieval (VIR) is an active and vibrant research area, which attempts at providing means for organizing, indexing, annotating, and retrieving visual information (images and videos) from large, unstructured repositories. The goal of VIR is to retrieve matches ranked by their relevance to a given query, which is often expressed as an example image and/or a series of keywords. During its early years (1995-2000), the research efforts were dominated by content-based approaches contributed primarily by the image and video processing community. During the past decade, it was widely recognized that the challenges imposed by the lack of coincidence between an image's visual contents and its semantic interpretation, also known as semantic gap, required a clever use of textual metadata (in addition to information extracted from the image's pixel contents) to make image and video retrieval solutions efficient and effective. The need to bridge (or at least narrow) the semantic gap has been one of the driving forces behind current VIR research. Additionally, other related research problems and market opportunities have started to emerge, offering a broad range of exciting problems for computer scientists and engineers to work on. In this introductory book, we focus on a subset of VIR problems where the media consists of images, and the indexing and retrieval methods are based on the pixel contents of those images -- an approach known as content-based image retrieval (CBIR). We present an implementation-oriented overview of CBIR concepts, techniques, algorithms, and figures of merit. Most chapters are supported by examples written in Java, using Lucene (an open-source Java-based indexing and search implementation) and LIRE (Lucene Image REtrieval), an open-source Java-based library for CBIR.

Abstract: Lately, 3D is gaining momentum in cinemas and home environments. However, 2D and 3D video content only stimulates senses like hearing and seeing. In this paper we focus on a more enhanced level of entertainment by presenting a 4D multimedia player and a corresponding demonstration setup, which stimulates further senses such as haptics using the MPEG-V: Media Context and Control standard. The presented demonstration setup uses stereoscopic 3D and sensory devices, i.e., fans, vibration panels and lights. The combination of conventional 3D content with tailored sensory effects allows us to further enhance the viewing experience of the users.

Abstract: Multimedia content is omnipresent in our life. Thus, one can consume content through various distribution channels such as a DVD, Blu-Ray, or the Internet. Recently, 3D video gained more and more importance and a lot of movies presented in cinemas are 3D. Currently, research on additional constituents such as light and scent effects for further enhancing the viewing experience is conducted. As this research is taken up by more and more researchers and companies, the Moving Picture Experts Group (MPEG) ratified the MPEG-V standard, referred to as Media Context and Control, which allows the annotation of multimedia content with additional effects (e.g., light, wind, vibration) and render these effects synchronized to the multimedia content. Due to this fairly new research area, there are only a few subjective quality assessments evaluating such effects. Moreover, standardized assessment methods cannot be used as originally developed since they are optimized for audio-visual quality evaluations. Thus, this work lists and describes existing subjective quality assessment methods suitable for conducting assessments comprising multimedia content, especially videos, enriched by sensory effects (i.e., light, wind, and vibration). As there is a lack of suitable software for rendering sensory effects, this work introduces a multimedia player for playing multimedia content accompanied by sensory effects. Moreover, in this work, we performed four subjective quality assessments answering the following questions: (1) Do sensory effects enhance the viewing experience for different genres? (2) Do sensory effects have an influence on the perceived video quality? (3) Do light effects enhance the viewing experience for Web videos? (4) Do sensory effects have an impact on the perceived emotions while watching a video? Therefore, this work presents these subjective quality assessments including a detailed description of the assessments and their results. Moreover, this work introduces a dataset consisting of video sequences annotated with sensory effects for conducting subjective quality assessments. Finally, some recommendations for performing assessments comprising sensory effects which have been extracted from the conducted subjective quality assessments are given.

Abstract: This paper provides an overview of our research conducted in the area of Sensory Experience including our implementations using MPEG-V Part 3 entitled ”Sensory Information”. MPEG-V Part 3 introduces Sensory Experience as a tool to increase the Quality of Experience by annotating traditional multimedia data with sensory effects. These sensory effects are rendered on special devices like fans, vibration chairs, ambient lights, scent disposers, water sprayers, or heating/cooling devices stimulating senses beyond the traditional ones. The paper's main focus is on the end-to-end aspects including the generation, transmission, and synchronized rendering of sensory effects with the traditional multimedia data taking movie clips as an example. Therefore, we present in this paper an open source tool chain that provides a complete end-to-end sensory effect generation and consumption framework. Furthermore, we summarize results from various subjective quality assessments conducted in this area. Finally, we point out research challenges that may encourage further research within this emerging domain.

Abstract: Enriching multimedia with additional effects such as olfaction, light, wind, or vibration is gaining more and more momentum in both research and industry. Hence, there is the need to determine the influence of individual effects on the Quality of Experience (QoE). In this paper, we present a subjective quality assessment using the MPEG-V standard to annotate video sequences with individual sensory effects (i.e., wind, light, and vibration) and all combinations thereof. Based on the results we derive a utility model for sensory experience that accounts for the assessed sensory effects. Finally, we provide an example instantiation of the utility model and validate it against current and past results of our subjective quality assessments conducted so far.

Abstract: Our approach to the ImageCLEF medical case retrieval task consists of text-only retrieval combined with utilizing the Medical Subject Headings (MeSH) ontology. MeSH terms extracted from the query are used for query expansion or query term weighting. MeSH annotations of documents available from PubMed Central are added to the corpus. Retrieval results improve slightly upon full-text retrieval.

Abstract: The MPEG-DASH standard allows the client-centric access to different representations of video content via the HTTP protocol. The client can flexibly switch between different qualities, i.e., different bit rates and thus avoid waiting times during the video playback due to empty playback buffers. However, quality switches and the playback of lower qualities is perceived by the user which may reduce the Quality of Experience (QoE). Therefore, novel algorithms are required which manage the streaming behavior with respect to the user's requirements and which do not waste network resources. As indicated by recent studies, scalable video coding (SVC) may use the current network and content distribution infrastructure in a more efficient way than with single layer codecs. The contribution of this paper is the design and the implementation of a novel DASH/SVC streaming algorithm. By means of measurements in a test-bed, its performance and benefits are evaluated and compared to existing algorithms from an user-centric view point with objective performance metrics. Our findings show that the proposed algorithm outperforms other DASH mechanisms in terms of video quality, low switching frequency and usage of the available resources in a realistic mobile network scenario. This is a first step towards true QoE management of video streaming in the Internet with DASH and SVC.

Abstract: The navigation features of video players are often used for interactive search in videos, when users want to find a specific segment. Especially non-experts make use of these navigation facilities because they typically do not have any video retrieval tool at hand and - maybe more important - the navigation features of video players are very easy to use. However, in order to design professional video browsing tools that allow for better search performance but still provide ease of use, we need to know how users search with common video players. Therefore, we analyze logging data from a user study with 17 participants that performed Known Item Search tasks with an HTML5 video player. We classify search behavior by type of interaction and speed of interactive search and discuss what we can learn for the design and development of professional video search tools.

Abstract: In this paper we present our approach to the Crowd Sourcing Task of the MediaEval 2013 Benchmark [2] using transfer learning and visual features. For the visual features we adopt an existing approach for search based classification using content based image retrieval on global features with feature selection and feature combination to boost the performance. Our approach gives a baseline evaluation indicating the usefulness of global visual features, hashing and search-based classification.

Abstract: Secure communication is often based on encryption thus hinges on (public-key) infrastructures that handle all the key-management. This inevitably requires human intervention, thus creating a rather vulnerable point in the system. So it appears desirable to automate key-management tasks to the widest possible extent. In this work, we report on a software implementation of secure multipath transmission. Our system takes a network infrastructure model as input and determines the maximal achievable security for a communication between a chosen sender and receiver, while handling all key-management transparently for the user. The security is information-theoretic, and unlike public-key or symmetric cryptography does neither hinge on computational intractability nor empirical evidence. More importantly, security can be measured in quantitative terms, thus making the results useful in enterprise risk management. Our software computes the risk for a given transmission under multipath transmission and generates simple OmNet++ models to demonstrate the channel construction as practically doable and to measure the additional network overhead. This is for a-priori decision-support and practical guidance for an installation of secure multipath transmission as a high-security transmission service within the enterprise network.

Abstract: Selecting and adopting the appropriate assessment method for conducting subjective quality assessments is a challenging task. The method decides whether the assessment is successful in delivering the correct answers to previously set up hypotheses. Therefore, in this paper we provide recommendations on test methods used in the domain of Sensory Experience. The proposed test methods comprise single stimulus and double stimulus methods. These test methods were used in previous studies and are presented in combination with the results of the subjective quality assessments with which they were used. Furthermore, we briefly outline our test setup, test design, and test content for assessing Sensory Experience which have been validated through conducted assessments.

Abstract: Synchronizing multimedia playback among geographically distributed clients is a challenging task and is referred to as Inter-Destination Media Synchronization (IDMS). In this paper we discuss the uses cases of IDMS as identified within the SocialSensor Project and based on these use cases we derive a novel Adaptive Media Playout (AMP) scheme which aims on carrying out the process of synchronizing the media playback at the clients to a given synchronization point. We propose how visual and acoustic features can be used to achieve a QoE-aware and context-aware AMP scheme.

Abstract: Preparing and conducting subjective quality assessments is a time consuming and expensive task. Therefore, we present a Web-based evaluation framework which aims on reducing the time needed for planning and designing a subjective quality assessment. The presented framework can be used for both crowdsourced and laboratory experiments. It should ease the task of designing a subjective quality assessment by providing a flexible framework. The framework has proven its applicability and flexibility to design and conduct assessments in the past and is available as open source.

Abstract: Emergency response operations are a promising application area for mobile ad-hoc networks (MANETs). Most existing MANET routing protocols assume that an end-toend path between source and destination can be established. However, this assumption may not hold in a hastily formed network established during an emergency response. This paper evaluates a store-and-forward mechanism for proactive routing protocols to mitigate the effects of network disruptions. The mechanism is integrated into two routing protocols. The modified protocols are evaluated in an emergency response scenario that includes a disaster area mobility model and a wireless obstacle model. The scenario represents a realistic first responder operation after an incident in a chemical facility. The evaluation results show that networks for disaster responses benefit from the modified routing protocols.