Showing papers by "Christian Timmerer published in 2016"

An evaluation of Heart Rate and ElectroDermal Activity as an objective QoE evaluation method for immersive virtual reality environments

Abstract: Recently, we have seen an emergence of affordable Head Mounted Displays (HMD) such as the Oculus Rift, HTC Vive, and the PS4 Project Morpheus which allow users to experience 3D virtual reality (VR). These types of hardware aim to facilitate new and novel experiences for users above and beyond what is possible with traditional audiovisual displays. However, a very limited number of studies exist in the literature to determine the influence of these technologies on user Quality of Experience (QoE). In order to evaluate QoE as users consume VR content, this paper proposes the use of affordable consumer electronics to capture objective physiological metrics: Heart Rate (HR) and ElectroDermal Activity (EDA). Our findings indicate different HR and EDA dependent on VR and non-VR environments. Additionally, we examine the relationship between these objective metrics and user QoE captured via a post-test questionnaire. To the best of the authors knowledge, this is the first work which demonstrates a tangible relationship between the EDA/HR combination and user QoE of immersive VR environments.

Which Adaptation Logic? An Objective and Subjective Performance Evaluation of HTTP-based Adaptive Media Streaming Systems.

Abstract: Multimedia content delivery over the Internet is predominantly using the Hypertext Transfer Protocol (HTTP) as its primary protocol and multiple proprietary solutions exits. The MPEG standard Dynamic Adaptive Streaming over HTTP (DASH) provides an interoperable solution and in recent years various adaptation logics/algorithms have been proposed. However, to the best of our knowledge, there is no comprehensive evaluation of the various logics/algorithms. Therefore, this paper provides a comprehensive evaluation of ten different adaptation logics/algorithms, which have been proposed in the past years. The evaluation is done both objectively and subjectively. The former is using a predefined bandwidth trajectory within a controlled environment and the latter is done in a real-world environment adopting crowdsourcing. The results shall provide insights about which strategy can be adopted in actual deployment scenarios. Additionally, the evaluation methodology described in this paper can be used to evaluate any other/new adaptation logic and to compare it directly with the results reported here.

Advanced Transport Options for the Dynamic Adaptive Streaming over HTTP.

Abstract: Multimedia streaming over HTTP is no longer a niche research topic as it has entered our daily live. The common assumption is that it is deployed on top of the existing infrastructure utilizing application (HTTP) and transport (TCP) layer protocols as is. Interestingly, standards like MPEG's Dynamic Adaptive Streaming over HTTP (DASH) do not mandate the usage of any specific transport protocol allowing for sufficient deployment flexibility which is further supported by emerging developments within both protocol layers. This paper investigates and evaluates the usage of advanced transport options for the dynamic adaptive streaming over HTTP. We utilize a common test setup to evaluate HTTP/2.0 and Google's Quick UDP Internet Connections (QUIC) protocol in the context of DASH-based services.

Transcoding and streaming-as-a-service for improved video quality on the web

Abstract: Real-time entertainment application such as the streaming of audio and video is responsible for the majority of today's Internet traffic. The transport thereof is accomplished over the top of the existing infrastructure and with MPEG-DASH interoperability is achieved. However, standards like MPEG-DASH only provide the format definition and the actual behavior of the corresponding implementations is left open for (industry) competition. In this demo paper we present our cloud encoding service and HTML5 adaptive streaming player enabling highest quality (i.e., no stalls and maximum media quality under the given conditions) and low start-up delay (for both live and on demand) at low (networking) costs. The demo comprises a feature-rich set of DASH-based application scenarios including much faster than real-time encoding/transcoding in the public cloud, live (device-to-device) streaming, support for digital rights management and advertisements, ultra high-definition and high frame rates, virtual reality, and 360° videos.

Guest Editorial Video Distribution Over Future Internet

Abstract: The current Internet is under tremendous pressure due to the exponential growth in bandwidth demand, fueled by the transfer of video consumption to online distribution, IPTV, streaming services such as Netflix, and from phone networks to videoconferencing and Skype-like video communications. The Internet has also democratized the creation, distribution and sharing of user-generated video contents through services such as YouTube, Vimeo or Hulu. The situation is further aggravated by the emerging trends of adopting higher definition video streams, requesting more and more bandwidth. Indeed, the Cisco Visual Networking Index (VNI) projects that video consumption will amount to 90% of the global consumer traffic by 2017. Another shift predicted by Cisco VNI is that most data communications will be wireless by 2018.

System and method for session mobility for adaptive bitrate streaming

Abstract: A system is provided, having a server, a first device for receiving a first plurality of segments of a media data stream from the server, and a second device for receiving a second plurality of segments of the media data stream from the server. A processor of the second device is configured to select said second plurality of segments of the media data stream depending on the context information, and depending on a replay offset or on a segment being rendered last by the first device or on a segment being received last by the first device. The interface of the second device is configured to request said second plurality of segments from the server. The server is configured to transmit said second plurality of segments to the second device.