ABSTRACT
We introduce a new methodology to evaluate the perceived quality of video with variable physical quality. The methodology is used to evaluate existing guidelines - that high frame rate is more important than quantization when watching high motion video, such as sports coverage. We test this claim in two studies that examine the relationship between these physical quality metrics and perceived quality. In Study 1, 41 soccer fans viewed CIF-sized images on a desktop computer. Study 2 repeated the experiment with 37 soccer fans, viewing the same content, in QCIF size, on a palmtop device. Contrary to existing guidelines, we found that users prefer high-resolution images to high frame rate. We conclude that the rule "high motion = high frame rate" does not apply to small screens. With small screen devices, reducing quantization removes important information about the players and the ball. These findings have important implications for service providers and designers of streamed video applications.
- Aldridge, R., Davidoff, J., Ghanbari, M., Hands, D. & Pearson, D. Measurement of scene-dependent quality variations in digitally-coded television pictures. IEE Proceedings on Vision, Signal and Image Processing, (1995) 142, 149--154.Google ScholarCross Ref
- Apteker, R.T, Fisher, J.A., Kisimov, V.S. & Neishlos, H. Video Acceptability and Frame Rate. IEEE Multimedia, 3(3):32--40, 1995. Google ScholarDigital Library
- Bouch, A & Sasse, M.A. The case for predictable media quality in networked multimedia applications. In K. Nahrstedt & W. Feng {Eds.}: Proceedings of ACM/SPIE Multimedia Computing and Networking (MMCN'00), 25-27th January 2000, San Jose, USA. pp 188--195.Google Scholar
- De Ridder, H. & Hamberg, R. Continuous Assessment of Image Quality. SMPTE Journal. 106(2): 123--128, Feb 1997.Google ScholarCross Ref
- Fechner, G. T. Elements of psychophysics (Vol. 1). (H. E. Adler, Trans. 1966). New York: Holt, Rinehart & Winston. (Original work published 1860).Google Scholar
- Fukuda, K. Integrated QOS control mechanisms for real-time multimedia systems in reservation -based networks. PHD Thesis, School of Engineering Science, Osaka University. Jan 2000. Available at http://www.anarg.jp/achievements/web1999/papers/k-fukuda/k-fukuda00PhD-IntegratedQoS.pdfGoogle Scholar
- Ghinea, G. and Thomas, J.P. QoS Impact on User Perception and Understanding of Multimedia Video Clips--in Proceedings of ACM Multimedia '98 (Bristol, UK, 1998) Google ScholarDigital Library
- Hamberg, R. & de Ridder, H. Time varying Image Quality: Modelling the relations between instantaneous and overall quality. SMPTE Journal, 802-811, Nov 1999.Google Scholar
- Hands, D. P-QoS for Mobile Multimedia available at http://www.iee.org/oncomms/pn/visualinformation/P-Qos_For_Mobile_Multimedia.pdfGoogle Scholar
- IBM. Functions of mobile multimedia QOS control (Updated Feb 2002). Available at http://www.trl.ibm.com/projects/mmqos/system_e.htmGoogle Scholar
- TU-R BT.500-11. Methodology for the subjective assessment of the quality of television pictures. Revised 2002.Google Scholar
- Knoche, H., De Meer, H. G. & Kirsh, D. Utility Curves: Mean Opinion Scores Considered Biased, Proceedings of 7th International Workshop on Quality of Service, 1st - 4th June 1999, University College London, London, UK.Google Scholar
- LC Technologies Inc. See http://www.eyegaze.com/Google Scholar
- Masry, M.A. and Hemami, S.S. CVQE: A metric for continuous video quality evaluation at low bit rates. IEEE Intl. Conf. on Image Processing 2001, Thessaloniki, Greece, October 2001.Google Scholar
- Wang, D., Speranza, F., Vincent, A., Martin, T. & Blanchfield, P. Towards Optimal Rate Control: A Study of the Impact of Spatial Resolution, Frame Rate and Quantization on Subjective Quality and Bitrate. Visual Communications and Image Processing (VCIP 2003).Google Scholar
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