Abstract: Scalable Video Coding (SVC) in media streaming enables dynamic adaptation based on device capabilities and network conditions. In this paper, we investigate deployment options of SVC for Dynamic Adaptive Streaming over HTTP (DASH) with a special focus on scalability options, which are relevant for dynamic adaptation, especially in wireless and mobile environments. We evaluate the performance of SVC with respect to spatial and quality scalability options and compare it to non-scalable Advanced Video Coding (AVC). Performance evaluations are performed for various encoder implementations with high-definition (1080p) content. We show that a hybrid approach with multiple independent SVC bitstreams can have advantages in storage requirements at comparable rate-distortion performance.

Abstract: When an adaptive media streaming system has to switch from one representation of the content to another, the switch causes viewer distraction. We introduce the concept of representation switch smoothing for alleviating the distraction and improving the overall quality of experience. As adaptive HTTP streaming systems typically deploy video buffers on the client side, the adaptation decision is known far enough ahead of playout time to perform a seamless transition between quality representations. We discuss implementation considerations for an adaptive HTTP streaming system with scalable video coding, present a subjective evaluation of the proposed approach, and identify factors that influence how smooth transitions are perceived.

Abstract: Scalability within media coding allows for content adaptation towards heterogeneous user contexts and enables in-network adaptation. However, there is no straightforward solution how to encode the content in a scalable way while maximizing rate-distortion performance. In this paper we provide encoding guidelines for scalable video coding based on a survey of media streaming industry solutions and a comprehensive performance evaluation using four state of the art scalable video codecs with a focus on high-definition content (1080p).

Abstract: We present an improved version of last year’s winner of the Video Browser Showdown. In a preprocessing step video segments are detected and clustered in several latent classes of similar content based on color and motion information. The navigation bars of our video browser are then augmented with different colors indicating where elements of the detected clusters are located. As humans are able to classify the content of clusters fast, they can benefit from this information when browsing through a video.

Abstract: While accuracy and speed get a lot of attention in video retrieval research, the investigation of interactive retrieval tools gets less attention and is often regarded as trivial. We want to show that even simple ideas have potential to improve the retrieval performance by giving some automated support to the browsing user. We present a video browsing concept where video segments are clustered in several latent classes of similar content. The navigation bars of our video browser are augmented with different colors indicating where elements of these clusters are located. As humans are able to classify the content of clusters fast, they can benefit from this information when browsing a video. We present a study where we investigated how humans can be supported in different video browsing tasks with a color-based and a motion-based clustering of video content.

Abstract: This paper shows how adaptive streaming and on-device caching can be used to provide an always available video service. A DASH client has been extended to deal with periods of zero network connectivity, and seamlessly works in conjunction with CCN to provide local storage that is intelligently updated to provide an improved quality of experience.

Abstract: The Video Browser Showdown (VBS) is a live competition for evaluating video browsing tools regarding their efficiency at known-item search (KIS) tasks. The first VBS was held at MMM 2012 with eight teams working on 14 tasks, of which eight were completed by expert users and six by novices. We describe the details of the competition, analyze results regarding the performance of tools, the differences between the tasks and the nature of the false submissions.

Abstract: Dynamic Adaptive Streaming over HTTP (DASH) is referred to as a multimedia streaming standard to deliver high quality multimedia content over the Internet using conventional HTTP Web servers. As a fundamental feature, it enables automatic switching of quality levels according to network conditions, user requirements, and expectations. Currently, the proposed adaptation schemes for HTTP streaming mostly rely on throughput measurements and/or buffer-related metrics, such as buffer exhaustion and levels. In this paper, we propose to enhance the DASH adaptation logic by feeding it with additional information from our evaluation of the users' perception approximating the user- perceived quality of video playback. The proposed model aims at conveniently combining TCP-, buffer-, and media content-related metrics as well as user requirements and expectations to be used as an input for the DASH adaptation logic. Experiments have demonstrated that the chosen model enhances the capability of the adaptation logic to select the optimal video quality level. Finally, we integrated all our findings into a real DASH system with QoE monitoring capabilities.

Abstract: Why do people record videos and share them? While the question seems to be simple, user intentions have not yet been investigated for video production and sharing. A general taxonomy would lead to adapted information systems and multimedia interfaces tailored to the users' intentions. We contribute (1) an exploratory user study with 20 participants, examining the various facets of user intentions for video production and sharing in detail and (2) a novel set of user intention clusters for video production, grounded empirically in our study results. We further reflect existing work in specialized domains (i.e. video blogging and mobile phone cameras) and show that prevailing models used in other multimedia fields (e.g. photography) cannot be used as-is to reason about video recording and sharing intentions.

Abstract: Additional constituents for the representation of multimedia content gained more and more attention. For example, the amount of cinemas equipped with additional devices (e.g., ambient light, vibrating seats, wind generators, water sprayers, heater/coolers) that stimulate senses going beyond audition and vision increases. On the content side the MPEG-V standard specifies – among others – Sensory Effect Metadata (SEM) which provides means to describe sensory effects such as wind, vibration, light, etc. to be attached to audio-visual content and, thus, offering an enhanced and immersive experience for the user. However, there is a lack of a common set of test content allowing for various subjective user studies and verification across different test sites. In this paper we provide our dataset comprising a number of videos from different genres enriched with MPEG-V compliant Sensory Effect Metadata descriptions. Furthermore, we describe possible test setups using off-the-shelf hardware for conducting subjective quality assessments.

Abstract: Multimedia content is increasingly used in every area of our life. Still, each type of content only stimulates the visual and/or the hearing system. Thus, the user experience depends only on those two stimuli. In this paper we introduce a standard which offers the possibility to add additional effects to multimedia content. Furthermore, we present a multimedia player and a Web browser plug-in which uses this standard to stimulate further senses by using additional sensory effects (i.e., wind, vibration, and light) to enhance the user experience resulting in a unique, worthwhile sensory experience.

Abstract: This paper describes a toolset for the authoring, simulating, and rendering of multimedia content annotated with Sensory Effect Metadata (SEM) descriptions as specified in Part 3 of the MPEG V standard. This part of MPEG-V standardizes the description of sensory effects (e.g., light, wind) in order to be rendered on sensory devices (e.g., fans, vibration chairs) aiming at generating a sensory experience stimulating possibly all human senses. Our implementation comprises a toolset to author sensory effects associated with multimedia content and the simulation thereof. Furthermore, it includes a library, a standalone player, and a Web browser plug-in which enables the playback and rendering of sensory effects on off-the-shelf rendering devices and in various contexts. All software modules are available under the GNU General Public License (GPL) v3 and the GNU Lesser General Public License (LGPL) v3 respectively.

Abstract: In this tutorial we present dynamic adaptive streaming over HTTP ranging from content creation to consumption. It particular, it provides an overview of the recently ratified MPEG-DASH standard, how to create content to be delivered using DASH, its consumption, and the evaluation thereof with respect to competing industry solutions. The tutorial can be roughly clustered into three parts. In part I we will provide an introduction to DASH, part II covers content creation, delivery, and consumption, and, finally, part III deals with the evaluation of existing (open source) MPEG-DASH implementations compared to state-of-art deployed industry solutions.

Abstract: We propose a video browser facilitating known-item search in a single video. Key frames are presented as four images at a time and can be navigated quickly in both forward and backward directions using a slider. Alternatively, key frames can be displayed automatically at different frame rates. The user may choose between three mappings of key frames to the four key frame widgets based on video time stamps and color similarity.

Abstract: In this paper we evaluate a 3D cylindrical interface that arranges image thumbnails by visual similarity for the purpose of image browsing. Through a user study we compare the performance of this interface to the performance of a common scrollable 2D list of thumbnails in a grid arrangement. Our evaluation shows that the 3D Cylinder interface enables significantly faster visual search and is the preferred search interface for the majority of tested users.

Abstract: With users increasingly using their mobile devices such as smartphones as digital photo albums, effective methods for managing these collections are becoming increasingly important. Standard solutions provide only limited facilities for organising, browsing and searching image collections on mobile devices, making it challenging and time-consuming to locate images of interest. In this demo paper, we present an intuitive interface for organising and browsing image collections on mobile devices. Images are arranged on a 3D globe according to colour similarity. To avoid image overlap image thumbnails are placed on a regular grid structure while large image collections are organised using a hierarchical data structure. Through multi-touch user interaction image browsing can be performed in an intuitive and effective manner.

Abstract: Interactive image and video search tools typically use a grid-like arrangement of thumbnails for preview purpose. Such a display, which is commonly known as storyboard, provides limited flexibility at interactive search and it does not optimally exploit the available screen estate. In this paper we design and evaluate alternatives to the common two-dimensional storyboard. We take advantage of 3D graphics in order to present image thumbnails in cylindrical arrangements. Through a user study we evaluate the performance of these interfaces in terms of visual search time and subjective performance.

Abstract: The design of interactive systems, especially in distributed research projects, is a challenging process in which many concepts are developed with successful outcomes but also with dissatisfying results. In order to structure and relay knowledge about good or bad approaches, design patterns are a well-known instrument in research and development. Due to the condition that a design pattern must be easy to read, different stakeholders in the system engineering and design process are able to understand the described concepts without the need of specific expert knowledge . In distributed projects, application design knowledge may be scattered and documented in different manners. This means, before we can start formulating patterns, we need to discover and gather the available and partially concealed design knowledge. Since these fragments of knowledge may not always be accurately formulated for being used as design patterns, we seek for a collaborative method for collecting and formulating early findings together with established design knowledge. In this paper we present a concept of an evolutionary process for capturing, formulating, refining and validating design patterns. Our approach aims at involving as many stakeholders as possible in order to shape a pattern language over a project’s lifetime in a collaborative process allowing facile participation. We implement our approach in the scope of the EU research project BRIDGE that aims at supporting inter-agency collaboration during emergency response. We close with a discussion of the current state and envisioned next steps in order to foster our considerations.