(2007) Gulliver, S. and Ghinea, G., The Perceptual Impact of Multimedia Delay and Jitter, IEEE International Conference on Multimedia and Expo 2007 (original) (raw)
Related papers
The Perceptual and Attentive Impact of Delay and Jitter In Multimedia Delivery
IEEE Transactions on Broadcasting, 2007
In this paper we present the results of a study that examines the user's perception-understood as both information assimilation and subjective satisfaction-of multimedia quality, when impacted by varying network-level parameters (delay and jitter). In addition, we integrate eye-tracking assessment to provide a more complete understanding of user perception of multimedia quality. Results show that delay and jitter significantly affect user satisfaction; variation in video eye path when either no single/obvious point of focus exists or when the point of attention changes dramatically. Lastly, results showed that content variation significantly affected user satisfaction, as well as user information assimilation.
In our study, we explore the human side of the multimedia experience. The authors propose a model that assesses quality variation from three distinct levels: the network-, the mediaand the content-levels; and from two views: the technicaland the user-perspective. By facilitating parameter variation at each of the quality levels and from each of the perspectives, we were able to examine their impact on user quality perception. Results show that: a significant reduction in frame rate does not proportionally reduce the user's understanding of the presentation, independent of technical parameters; the type of video clip significantly impacts user information assimilation, user level of enjoyment and user perception of quality;
Changing frame rate, changing satisfaction? [multimedia quality of perception]
2004
Perceptual indicators of multimedia quality have to be taken into account in order to build the truly end-toend communication architectures of the future. This paper investigates the perceptual impact of differing multimedia presentation frame rates on user information assimilation and level of satisfaction. We apply the Quality of Perception (QoP) concept, which encompasses not only a user's ability to analyse, synthesise and assimilate informational content of multimedia but also his/her satisfaction with the quality of a multimedia presentation. Our results show that higher frame rates, although resulting in a betterperceived level of quality and enjoyment, across a range of video content, do not significantly increase the level of user information assimilation.
2008
In our study, we explore the human side of the multimedia experience. The authors propose a model that assesses quality variation from three distinct levels: the network-, the media- and the content-levels; and from two views: the technical- and the user-perspective. By facilitating parameter variation at each of the quality levels and from each of the perspectives, we were able to examine their impact on user quality perception. Results show that: a significant reduction in frame rate does not proportionally reduce the user's understanding of the presentation, independent of technical parameters; the type of video clip significantly impacts user information assimilation, user level of enjoyment and user perception of quality; the display type impacts user information assimilation and user perception of quality. Finally, to ensure transfer of informational content, network parameter variation should be adapted; to maintain user enjoyment, video content variation should be adapted.
If commercial multimedia development continues to ignore the user-perspective in preference of other factors, i.e. user fascination (i.e. the latest gimmick), then companies ultimately risk alienating the customer. Moreover, by ignoring the user-perspective, future distributed multimedia systems risk ignoring accessibility issues, by excluding access for users with abnormal perceptual requirements. This paper presents an extensive examination of distributed multimedia quality. We define a model that considers multimedia quality from three distinct levels: the network, the media-and the content-levels; and two views: the technical-and the user-perspective. By manipulating both technical and user-perspective parameters, we examine the impact on quality perception at the three quality levels identified. Results show that: a significant reduction in frame rate does not proportionally reduce the user's understanding of the presentation, independent of technical parameters; the type of video clip significantly impacts user information assimilation, user level of enjoyment and user perception of quality; the display type impacts user information assimilation and user perception of quality. Finally, to ensure transfer of informational content, network parameter variation should be adapted; to maintain user enjoyment, video content variation should be adapted.
Perceptual Multimedia Quality: Implications of an Empirical Study
If commercial multimedia development continues to ignore the user-perspective in preference of other factors, i.e. user fascination (i.e. the latest gimmick), then companies ultimately risk alienating the customer. Moreover, by ignoring the user-perspective, future distributed multimedia systems risk ignoring accessibility issues, by excluding access for users with abnormal perceptual requirements. This paper presents an extensive examination of distributed multimedia quality. We define a model that considers multimedia quality from three distinct levels: the network, the media-and the content-levels; and two views: the technical-and the user-perspective. By manipulating both technical and user-perspective parameters, we examine the impact on quality perception at the three quality levels identified. Results show that: a significant reduction in frame rate does not proportionally reduce the user's understanding of the presentation, independent of technical parameters; the type of video clip significantly impacts user information assimilation, user level of enjoyment and user perception of quality; the display type impacts user information assimilation and user perception of quality. Finally, to ensure transfer of informational content, network parameter variation should be adapted; to maintain user enjoyment, video content variation should be adapted.
SPIE Proceedings, 1998
The conventional synchronous model of digital video, in which video is reconstructed synchronously at the decoder on a frame-by-frame basis, assumes its transport is delayjitter-free. This assumption is inappropriate for modern integrated service packet networks such as the Internet for network delay jitter varies widely. Furthermore, multiframe buffering is not a viable solution in interactive applications such as video conferencing. We have proposed a "delay cognizant" model of video coding (DCVC) that segments an incoming video into two video flows with different delay attributes. The DCVC decoder operates in an asynchronous reconstruction mode that attempts to maintain image quality in the presence of network delay jitter. Our goal is to maximize the allowable delay of one flow relative to that of the other with minimal effect on image quality since an increase in the delay offset reflects more tolerance to transmission delay jitter. Subjective quality evaluations indicated for highly compressed sequences, differences in video quality of reconstructed sequences with large delay offsets as compared with zero delay offset are small. Moreover, in some cases asynchronously reconstructed video sequences look better than the zero delay case. DCVC is a promising solution to transport delay jitter in low-bandwidth video conferencing with minimal impact on video quality.