This paper presents a model to predict video quality perceived by the broadcast digital television (DTV) viewer. We present how noise on DTV can introduce individual transport stream (TS) packet losses at the receiver. The type of these errors is different than the produced on IP networks. Different scenarios of TS packet loss are analyzed, including uniform and burst distributions. The results show that there is a high variability on the perceived quality for a given percentage of packet loss and type of error. This implies that there is practically no correlation between the type of error or the percentage of packets loss and the perceived degradation. A new metric is introduced, the weighted percentage of slice loss, which takes into account the affected slice type in each lost TS packet. We show that this metric is correlated with the video quality degradation. A novel parametric model for video quality estimation is proposed, designed, and verified based on the results of subjective tests in SD and HD. The results were compared to a standard model used in IP transmission scenarios. The proposed model improves Pearson Correlation and root mean square error between the subjective and the predicted MOS. 1. Introduction Television is by far the communications service with higher penetration in society. It reaches every household in many countries of the world. Broadband Internet access does not have such an extended penetration in some countries. While in developing countries 72.4% of households have a TV set, only 22.5% have a computer and only 15.8% have Internet access (compared to 98%, 71%, and 65.6%, resp., in developed countries) [1]. In order to care for bringing quality to the people through communications services it is essential to be concerned about the quality delivered by the TV services. Nowadays great attention is given to Digital Television (DTV). Many countries in the world have already made the so-called “analog switch-off” which means that all analog TV transmitters in a given country or city are finally switched off, paving the way to new usage of the spectrum. Some other countries are planning it for some time between 2015 and 2020. The completion of the analog switch-off will imply the end of the migration from analog TV to DTV. The above mentioned applies to Terrestrial Digital Television, that is, the traditional free-to-air TV service. However, there are also some other transmitting mediums used for TV services, mainly for Pay TV, which were digitalized many years ago. Those are the cases of satellite TV and cable TV. Besides,
References
[1]
ITU, “The World in 2010: ICT Facts and Figures,” 2010, http://www.itu.int/ITU-D/ict/material/FactsFigures2010.pdf.
[2]
ISO/IEC, “ISO/IEC, 13818-1: MPEG-2 Part1. Information technology—generic coding of moving pictures and associated audio information: systems”.
[3]
ATSC, http://www.atsc.org/.
[4]
DVB, http://www.dvb.org/.
[5]
ARIB, http://www.arib.or.jp/english/.
[6]
G. J. Sullivan and T. Wiegand, “Video compression-from concepts to the H.264/AVC standard,” Proceedings of the IEEE, vol. 93, no. 1, pp. 18–31, 2005.
[7]
Y. J. Liang, J. G. Apostolopoulos, and B. Girod, “Analysis of packet loss for compressed video: effect of burst losses and correlation between error frames,” IEEE Transactions on Circuits and Systems for Video Technology, vol. 18, no. 7, pp. 861–874, 2008.
[8]
F. You, W. Zhang, and J. Xiao, “Packet loss pattern and parametric video quality model for IPTV,” in Proceedings of the 8th IEEE/ACIS International Conference on Computer and Information Science (ICIS '09), pp. 824–828, June 2009.
[9]
M. H. Pinson, S. Wolf, and G. Cermak, “HDTV subjective quality of H.264 vs. MPEG-2, with and without packet loss,” IEEE Transactions on Broadcasting, vol. 56, no. 1, pp. 86–91, 2010.
[10]
N. Chen, X. Jiang, and C. Wang, “Impact of packet loss distribution on the perceived IPTV video quality,” in Proceedings of the 5th International Congress on Image and Signal Processing (CISP '12), pp. 38–42, 2012.
[11]
M. Leszczuk, L. Janowski, P. Romaniak, and Z. Papir, “Assessing quality of experience for high definition video streaming under diverse packet loss patterns,” Signal Processing: Image Communication, vol. 28, no. 8, pp. 903–916, 2013.
[12]
H. Schulzrinne, S. Casner, R. Frederick, and V. Jacobson, “RFC, 3550 RTP: A Transport Protocol for Real-Time Applications,” 2003.
[13]
ETSI, “300 744 V1. 6. 1 (2009-01): Digital video broadcasting (DVB), framing structure, channel coding and modulation for digital terrestrial television,” 2009.
[14]
F. C. C. De Castro, M. C. F. De Castro, M. A. C. Fernandes, and D. S. Arantes, “8-VSB channel coding analysis for DTV broadcast,” IEEE Transactions on Consumer Electronics, vol. 46, no. 3, pp. 539–547, 2000.
[15]
W. Fischer, Digital Video and Audio Broadcasting Technology, Chapter 12, Springer, Berlin, Germany, 2010.
[16]
T. Kratochvil and V. Ricny, “Simulation and experimental testing of the DVB-T broadcasting in the SFN networks,” in Proceedings of the 18th International Conference Radioelektronika, April 2008.
[17]
G. Bedicks, F. Sukys, E. L. Horta et al., “Field measurements for ISDB-TB in the VHF band,” in Proceedings of the IEEE International Symposium on Broadband Multimedia Systems and Broadcasting (BMSB '11), June 2011.
[18]
C. Akamine, F. Yamada, G. Bedicks Jr. et al., “Field trial for Brazilian DTV using space diversity,” in Proceedings of the IEEE International Symposium on Broadband Multimedia Systems and Broadcasting (BMSB '10), March 2010.
[19]
D. Zegarra Rodriguez and G. Bressan, “Video quality assessments on digital TV and video streaming services using objective metrics,” IEEE Latin America Transactions, vol. 10, no. 1, pp. 1184–1189, 2012.
[20]
S. R. Martin, “RF performance of DTV converter boxes-an overview of FCC measurements,” IEEE Transactions on Broadcasting, vol. 56, no. 4, pp. 441–451, 2010.
[21]
T. S. Bonfim and M. M. Carvalho, “Video Quality Evaluation for a Digital Television Broadcasting Scenario,” http://enpub.fulton.asu.edu/resp/vpqm/vpqm10/proceedings_vpqm2010/vpqm_p41.pdf.
[22]
T. Kratochvíl and R. ？tukavec, “DVB-T digital terrestrial television transmission over fading channels,” Radioengineering, vol. 17, no. 3, pp. 96–102, 2008.
[23]
DVB, “ETSI TR 101 290, Measurement guidelines for DVB systems,” Digital Video Broadcasting.
[24]
G. Hasslinger and O. Hohlfeld, “The Gilbert-Elliott model for packet loss in real time services on the Internet,” in Proceedings of the 14th GI/ITG Conference on Measuring, Modelling and Evaluation of Computer and Communication Systems (MMB '08), 2008.
[25]
N. B. Yoma, C. Busso, and I. Soto, “Packet-loss modelling in IP networks with state-duration constraints,” IEE Proceedings on Communications, vol. 152, no. 1, pp. 1–5, 2005.
[26]
J. Greengrass, J. Evans, and A. C. Begen, “Not all packets are equal, Part 2: the impact of network packet loss on video quality,” IEEE Internet Computing, vol. 13, no. 2, pp. 74–82, 2009.
[27]
K. D. Singh and G. Rubino, “Quality of experience estimation using frame loss pattern and video encoding characteristics in DVB-H networks,” in Proceedings of the 18th International Packet Video Workshop (PV '10), pp. 150–157, December 2010.
[28]
ITU, “Recommendation ITU-R BT. 500-13, Methodology for the subjective assessment of the quality of television pictures,” January 2012.
[29]
ITU, “Recommnedation ITU-R BT. 710-4 Subjective Assessment Methods for Image Quality in High Definition Television,” November 1998.
[30]
ITU, “Recommendation ITU-T P. 910 Subjective video quality assessment methods,” April 2008.
[31]
The Consumer Digital Video Library, http://www.cdvl.org.
J. Joskowicz, R. Sotelo, and J. C. L. Ardao, “Comparison of parametric models for video quality estimation: towards a general model,” in Proceedings of the IEEE International Symposium on Broadband Multimedia Systems and Broadcasting (BMSB '12), Seoul, Republic of Korea, 2012.
[34]
ITU-T, “Recommendation ITU-T G. 1070: opinion model for video-telephony applications,” July 2012.
[35]
K. Yamagishi and T. Hayashi, “Parametric packet-layer model for monitoring video quality of IPTV services,” in Proceedings of the IEEE International Conference on Communications (ICC '08), pp. 110–114, May 2008.
[36]
J. Joskowicz and J. C. L. Ardao, “Combining the effects of frame rate, bit rate, display size and video content in a parametric video quality model,” in Proceedings of the 6th IFIP/ACM Latin America Networking Conference (LANC '11), pp. 4–11, October 2011.
