1. Trang chủ
  2. » Kỹ Thuật - Công Nghệ

Biomedical Engineering 2012 Part 7 ppt

40 308 1

Đang tải... (xem toàn văn)

Tài liệu hạn chế xem trước, để xem đầy đủ mời bạn chọn Tải xuống

THÔNG TIN TÀI LIỆU

Thông tin cơ bản

Định dạng
Số trang 40
Dung lượng 1,79 MB

Nội dung

BiomedicalEngineering232 diagnosis. Again, all video qualities qualified for urgent clinical practice, however QPs of 44/36/28 is recommended. The same allegations stand for constant QP encoding, whereas for rate control, similar to CIF resolution, videos attaining PSNR higher than 30.5 db. 20 25 30 35 40 45 50 0 100 200 300 400 500 600 BitRate (kbps) Y-SNR (db ) IPPP IBPBP IBBPBBP 20 25 30 35 40 45 50 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP a ) b) Fig. 5. Rate-distortion curves for tested frame encoding schemes. a) QCIF and b) CIF. 25 27 29 31 33 35 37 39 41 43 45 0 100 200 300 400 500 600 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP 25 27 29 31 33 35 37 39 41 43 45 0 100 200 300 400 500 600 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP a ) b) 25 27 29 31 33 35 37 39 41 43 45 0 100 200 300 400 500 600 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP 25 27 29 31 33 35 37 39 41 43 45 0 100 200 300 400 500 600 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP c ) d) Fig. 6. Rate-distortion curves for tested frame encoding schemes, QCIF resolution. a) 2%, b) 5%, c) 8% and d) 10% loss rates. IBBPBBP encoding scheme attains higher PSNR ratings in most cases, especially in low-noise (up to 5%) scenarios. 25 27 29 31 33 35 37 39 41 43 45 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PS NR (db) IPPP IBPBP IBBPBBP 25 27 29 31 33 35 37 39 41 43 45 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP a ) b) 25 27 29 31 33 35 37 39 41 43 45 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP 25 27 29 31 33 35 37 39 41 43 45 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP c ) d) Fig. 7. Rate-distortion curves for tested frame encoding schemes, CIF resolution. a) 2%, b) 5%, c) 8% and d) 10% loss rates. Bi-directional prediction (IBPBP and IBBPBBP) achieves better results up to 5% loss rates (low-noise), whereas as the noise level increases, single – directional (IPPP) provides for better error recovery. 20 25 30 35 40 45 50 0 200 400 600 800 1000 1200 Bit Rate (kbps) Y-PSNR (db) Constant QP Rate Control Variable QP FMO 20 25 30 35 40 45 50 0 200 400 600 800 1000 1200 Sequence Bit Rate (kbps) ROI Y-PSNR (db) Constant QP Rate Control Variable QP FMO a ) b) Fig. 8. Rate-distortion curves for a) entire video, QCIF resolution with ECG lead and b) atherosclerotic plaque extracted from QCIF resolution video with ECG lead (diagnostic ROI). Observe that Variable QP FMO encoding attains inferior quality for the whole video, when it comes to diagnostic quality however it outperforms rate control encoding, while it achieves similar PSNR ratings with constant QP encoding, the key observation being the drastically lower bitrate it involves. TowardsDiagnosticallyRobustMedicalUltrasoundVideoStreamingusingH.264 233 diagnosis. Again, all video qualities qualified for urgent clinical practice, however QPs of 44/36/28 is recommended. The same allegations stand for constant QP encoding, whereas for rate control, similar to CIF resolution, videos attaining PSNR higher than 30.5 db. 20 25 30 35 40 45 50 0 100 200 300 400 500 600 BitRate (kbps) Y-SNR (db ) IPPP IBPBP IBBPBBP 20 25 30 35 40 45 50 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP a ) b) Fig. 5. Rate-distortion curves for tested frame encoding schemes. a) QCIF and b) CIF. 25 27 29 31 33 35 37 39 41 43 45 0 100 200 300 400 500 600 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP 25 27 29 31 33 35 37 39 41 43 45 0 100 200 300 400 500 600 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP a ) b) 25 27 29 31 33 35 37 39 41 43 45 0 100 200 300 400 500 600 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP 25 27 29 31 33 35 37 39 41 43 45 0 100 200 300 400 500 600 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP c ) d) Fig. 6. Rate-distortion curves for tested frame encoding schemes, QCIF resolution. a) 2%, b) 5%, c) 8% and d) 10% loss rates. IBBPBBP encoding scheme attains higher PSNR ratings in most cases, especially in low-noise (up to 5%) scenarios. 25 27 29 31 33 35 37 39 41 43 45 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PS NR (db) IPPP IBPBP IBBPBBP 25 27 29 31 33 35 37 39 41 43 45 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP a ) b) 25 27 29 31 33 35 37 39 41 43 45 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP 25 27 29 31 33 35 37 39 41 43 45 0 200 400 600 800 1000 1200 1400 1600 1800 BitRate (kbps) Y-PSNR (db) IPPP IBPBP IBBPBBP c ) d) Fig. 7. Rate-distortion curves for tested frame encoding schemes, CIF resolution. a) 2%, b) 5%, c) 8% and d) 10% loss rates. Bi-directional prediction (IBPBP and IBBPBBP) achieves better results up to 5% loss rates (low-noise), whereas as the noise level increases, single – directional (IPPP) provides for better error recovery. 20 25 30 35 40 45 50 0 200 400 600 800 1000 1200 Bit Rate (kbps) Y-PSNR (db) Constant QP Rate Control Variable QP FMO 20 25 30 35 40 45 50 0 200 400 600 800 1000 1200 Sequence Bit Rate (kbps) ROI Y-PSNR (db) Constant QP Rate Control Variable QP FMO a ) b) Fig. 8. Rate-distortion curves for a) entire video, QCIF resolution with ECG lead and b) atherosclerotic plaque extracted from QCIF resolution video with ECG lead (diagnostic ROI). Observe that Variable QP FMO encoding attains inferior quality for the whole video, when it comes to diagnostic quality however it outperforms rate control encoding, while it achieves similar PSNR ratings with constant QP encoding, the key observation being the drastically lower bitrate it involves. BiomedicalEngineering234 20 25 30 35 40 45 50 0 500 1000 1500 2000 2500 3000 3500 4000 Bit Rate (kbps) Y-PSNR (db) Constant QP Rate Control Variable QP FMO 20 25 30 35 40 45 50 0 500 1000 1500 2000 2500 3000 3500 4000 Sequence Bit Rate (kbps) Y-PS NR (db) Constant QP Rate Control Variable QP FMO a ) b) Fig. 9. Rate-distortion curves for a) entire video, CIF resolution video with ECG lead and b) atherosclerotic plaque extracted from CIF resolution video with ECG lead (diagnostic ROI). Observe that Variable QP FMO encoding attains inferior quality for the whole video, when it comes to diagnostic quality however it outperforms rate control encoding, while it achieves similar PSNR ratings with constant QP encoding, the key observation being the drastically lower bitrate it involves. 20 25 30 35 40 45 0 200 400 600 800 1000 1200 Sequence Bit Rate (kbps) ROI Y-PSNR (db) Constant QP Rate Control Variable QP FMO 20 25 30 35 40 45 0 500 1000 1500 2000 2500 3000 3500 4000 Sequence Bit Rate (kbps) Y-PSNR (db) Constant QP Rate Control Variable QP FMO a ) b) Fig. 10. Rate-distortion curves for a) atherosclerotic plaque extracted from QCIF resolution video with ECG lead, 5% loss rate and b) atherosclerotic plaque extracted from CIF resolution video with ECG lead, 5% loss rate. Variable QP FMO encoding attains the best diagnostic performance. Better error recovery compared to constant QP encoding is due to the fact that FMO employs slice encoding. Bandwidth requirements reductions as to Figures 8-9. Constant QP Rate Control Variable QP FMO Constant QP vs Variable QP FMO Rate Control vs Variable QP FMO PSNR Seq. BitRate PSNR Seq. BitRate PSNR Seq. BitRate Db Gain BitRate Reduction Db Gain BitRate Reduction 33.08 235 29.19 82 33.19 82 0.11 153 4 Negligible 34.88 508 30.69 157 36.06 156 1.18 352 5.37 36.51 960 33.01 302 38.65 301 2.14 659 5.64 37.47 1642 33.67 562 40.77 561 3.30 1081 7.10 38.04 2554 35.6 960 42.56 959 4.52 1595 6.96 Table 5. Atherosclerotic plaque extracted from CIF resolution video, no ECG lead - 5% Loss Rate. 6. Conclusion and Future Work M-Health systems and services facilitated a revolution in remote diagnosis and care. Driven by advances in networking, video compression and computer technologies, wide deployment of such systems and services is expected in the near future. Before such a scenario becomes a reality however, there are a number of issues that have to be addressed. Video streaming of medical video over error prone wireless channels is one critical issue that needs to be addressed. Remote diagnosis is very sensitive to the amount of clinical data recovered, hence the effort should be directed towards the provision of robust medical video at a required bitrate for the medical expert to provide a confident and accurate diagnosis. H.264/AVC encompasses powerful video coding and error resilience tools, exploitation of which can significantly improve video quality. We present an evaluation of different frame types and encoding modes of H.264/AVC and how they relate to diagnostic performance. In addition, an efficient, diagnostically relevant approach is proposed for encoding and transmission of medical ultrasound video of the carotid artery. Driven by its diagnostic use, ultrasound video is segmented and encoded using flexible macroblock ordering (FMO). FMO type 2 concept is extended to support variable quality slice encoding. Diagnostic region(s) of interest are encoded in high quality whereas the remaining, non-diagnostic region, is heavily compressed. Both technical and clinical evaluation show that enhanced diagnostic performance is attained in the presence of errors while at the same time achieving significant bandwidth requirements reductions. Future work includes the insertion of redundant slices (RS) describing diagnostically important region(s) in the resulting bitstream, maximizing medical video’s error resilience under severe packet losses (Panayides et al., 2009). We will also explore the application of these technologies to other medical video modalities. 7. Acknowledgement This work was funded via the project Real-Time Wireless Transmission of Medical Ultrasound Video of the Research and Technological Development 2008-2010, of the Research Promotion Foundation of Cyprus. TowardsDiagnosticallyRobustMedicalUltrasoundVideoStreamingusingH.264 235 20 25 30 35 40 45 50 0 500 1000 1500 2000 2500 3000 3500 4000 Bit Rate (kbps) Y-PSNR (db) Constant QP Rate Control Variable QP FMO 20 25 30 35 40 45 50 0 500 1000 1500 2000 2500 3000 3500 4000 Sequence Bit Rate (kbps) Y-PS NR (db) Constant QP Rate Control Variable QP FMO a ) b) Fig. 9. Rate-distortion curves for a) entire video, CIF resolution video with ECG lead and b) atherosclerotic plaque extracted from CIF resolution video with ECG lead (diagnostic ROI). Observe that Variable QP FMO encoding attains inferior quality for the whole video, when it comes to diagnostic quality however it outperforms rate control encoding, while it achieves similar PSNR ratings with constant QP encoding, the key observation being the drastically lower bitrate it involves. 20 25 30 35 40 45 0 200 400 600 800 1000 1200 Sequence Bit Rate (kbps) ROI Y-PSNR (db) Constant QP Rate Control Variable QP FMO 20 25 30 35 40 45 0 500 1000 1500 2000 2500 3000 3500 4000 Sequence Bit Rate (kbps) Y-PSNR (db) Constant QP Rate Control Variable QP FMO a ) b) Fig. 10. Rate-distortion curves for a) atherosclerotic plaque extracted from QCIF resolution video with ECG lead, 5% loss rate and b) atherosclerotic plaque extracted from CIF resolution video with ECG lead, 5% loss rate. Variable QP FMO encoding attains the best diagnostic performance. Better error recovery compared to constant QP encoding is due to the fact that FMO employs slice encoding. Bandwidth requirements reductions as to Figures 8-9. Constant QP Rate Control Variable QP FMO Constant QP vs Variable QP FMO Rate Control vs Variable QP FMO PSNR Seq. BitRate PSNR Seq. BitRate PSNR Seq. BitRate Db Gain BitRate Reduction Db Gain BitRate Reduction 33.08 235 29.19 82 33.19 82 0.11 153 4 Negligible 34.88 508 30.69 157 36.06 156 1.18 352 5.37 36.51 960 33.01 302 38.65 301 2.14 659 5.64 37.47 1642 33.67 562 40.77 561 3.30 1081 7.10 38.04 2554 35.6 960 42.56 959 4.52 1595 6.96 Table 5. Atherosclerotic plaque extracted from CIF resolution video, no ECG lead - 5% Loss Rate. 6. Conclusion and Future Work M-Health systems and services facilitated a revolution in remote diagnosis and care. Driven by advances in networking, video compression and computer technologies, wide deployment of such systems and services is expected in the near future. Before such a scenario becomes a reality however, there are a number of issues that have to be addressed. Video streaming of medical video over error prone wireless channels is one critical issue that needs to be addressed. Remote diagnosis is very sensitive to the amount of clinical data recovered, hence the effort should be directed towards the provision of robust medical video at a required bitrate for the medical expert to provide a confident and accurate diagnosis. H.264/AVC encompasses powerful video coding and error resilience tools, exploitation of which can significantly improve video quality. We present an evaluation of different frame types and encoding modes of H.264/AVC and how they relate to diagnostic performance. In addition, an efficient, diagnostically relevant approach is proposed for encoding and transmission of medical ultrasound video of the carotid artery. Driven by its diagnostic use, ultrasound video is segmented and encoded using flexible macroblock ordering (FMO). FMO type 2 concept is extended to support variable quality slice encoding. Diagnostic region(s) of interest are encoded in high quality whereas the remaining, non-diagnostic region, is heavily compressed. Both technical and clinical evaluation show that enhanced diagnostic performance is attained in the presence of errors while at the same time achieving significant bandwidth requirements reductions. Future work includes the insertion of redundant slices (RS) describing diagnostically important region(s) in the resulting bitstream, maximizing medical video’s error resilience under severe packet losses (Panayides et al., 2009). We will also explore the application of these technologies to other medical video modalities. 7. Acknowledgement This work was funded via the project Real-Time Wireless Transmission of Medical Ultrasound Video of the Research and Technological Development 2008-2010, of the Research Promotion Foundation of Cyprus. BiomedicalEngineering236 8. References Doukas, C. & Maglogiannis, I. (2008). Adaptive Transmission of Medical Image and Video Using Scalable Coding and Context-Aware Wireless Medical Networks, EURASIP Journal on Wireless Communications and Networking, Vol. 2008, Article ID 428397, 12 pages. doi:10.1155/2008/428397. Fielding, R.; Gettys, J.; Mogul, J.; Frystyk, H.; Masinter, L.; Leach, P. & Berners-Lee, T. (1999). Hypertext Transfer Protocol-HTTP/1.1., Internet Engineering Task Force, RFC 2616, 1999. H.264/AVC JM 15.1 Reference Software, Available: http://iphome.hhi.de/suehring/tml/. Handley, M.; Schulzrinne, H.; Schooler, E. & Rosenberg, J. (1999). SIP: Session Initiation Protocol, Internet Engineering Task Force, RFC 2543, Mar. 1999. Hennerici, M. & Neuerburg-Heusler, D. (1998). Vascular Diagnosis With Ultrasound, Thieme, 0865776032, 9780865776036, Stutgart - New York. Istepanian, R.H.; Laxminarayan, S. & Pattichis, C.S. (2006). M-Health: Emerging Mobile Health Systems, Springer, 0387265589, 9780387265582, New York. Joint Video Team of ITU-T and ISO/IEC JTC 1. (2003). Draft ITU-T Recommendation and Final Draft International Standard of Joint Video Specification (ITU-T Rec. H.264 | ISO/IEC 14496-10 AVC), Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG, JVTG050, Mar. 2003. Kyriacou, E.; Pattichis, M.S.; Pattichis, C.S.; Panayides, A. & Pitsillides, A. (2007). M-Health e-Emergency Systems: Current Status and Future Directions [Wireless corner], Antennas and Propagation Magazine, IEEE , Vol. 49, No. 1, Feb. 2007, pp. 216-231, 1045-9243. Lambert, P.; De Neve, W.; Dhondt, Y. & Van De Walle, R. (2006). Flexible macroblock ordering in H.264/AVC, Journal of Visual Communication and Image Representation, Vol. 17, No. 2, Apr. 2006, pp. 358-375, 10473203. Li, Z.G.; Pan, F.; Lim, K.P.; Feng, G.N.; Lin X. & Rahardaj, S. (2003). Adaptive basic unit layer rate control for JVT, JVT-G012, 7th meeting, Pattaya II, Thailand, 7-14, Mar. 2003. Loizou, C.P.; Pattichis, C.S.; Christodoulou, C.I.; Istepanian, R.S.H.; Pantziaris, M. & Nicolaides, A. (2005). Comparative evaluation of despeckle filtering in ultrasound imaging of the carotid artery, IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, Vol. 52, No. 10, Oct. 2005, pp. 1653-1669, 0885-3010. Loizou, C.P.; Pattichis, C.S.; Pantziaris, M. & Nicolaides, A. (2007). An integrated system for the segmentation of atherosclerotic carotid plaque, IEEE Transactions on Information Technology in Biomedicine, Vol. 11, No. 5, Nov. 2007, pp. 661-667, 1089-7771. Loizou, C.P. & Pattichis C.S. (2008). Despeckle filtering algorithms and Software for Ultrasound Imaging, Synthesis Lectures on Algorithms and Software for Engineering, Ed. Morgan & Claypool Publishers, 13: 9781598296204, USA. Panayides, A.; Pattichis, M. S. & Pattichis, C. S. (2008). Wireless Medical Ultrasound Video Transmission Through Noisy Channels, Proceedings of the 30 th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC’08), pp. 5326-5329, 1557-170X, Aug. 2008, Vancouver, Canada. Panayides, A.; Pattichis, M. S.; Pattichis, C. S.; Loizou, C. P.; Pantziaris, M. and Pitsillides, A. (2009). Robust and Efficient Ultrasound Video Coding in Noisy Channels Using H.264, to be published in Proceedings of the 31 st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC’09), Sep. 2009, Minnesota, U.S.A. Park S. & Miller, K. (1998). Random Number Generators: Good Ones Are Hard To Find, Communications of the ACM, Vol. 31, No. 10, Oct. 1988, pp. 1192 - 1201,0001-0782. Postel, J. (1980). User Datagram Protocol, Internet Engineering Task Force, RFC 768, 1980. Postel, J. (1981). Transmission Control Protocol, Internet Engineering Task Force, RFC 793, 1981. Rao, S. & Jayant, N. (2005). Towards high quality region-of-interest medical video over wireless networks using lossless coding and motion compensated temporal filtering, Proceedings of the fifth IEEE International Symposium on Signal Processing and Information Technology (ISSPIT’05), pp. 618-623, 0-7803-9313-9, Dec. 2005, Athens, Greece. Schulzrinne, H.; Casner, S.; Frederick, R. & Jacobson, V. (1996). RTP: A Transport Protocol for Real-Time Applications, Internet Engineering Task Force, RFC 1889, Jan. 1996. Schulzrinne, H.; Rao, A. & Lanphier, R. (1998). Real-Time Session Protocol (RTSP), Internet Engineering Task Force, RFC 2326, Apr. 1998. Tsapatsoulis N.; Loizou, C. & Pattichis, C. (2007). Region of Interest Video Coding for Low bit-rate Transmission of Carotid Ultrasound Videos over 3G Wireless Networks, Proceedings of the 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC’07), pp. 3717-3720, 978-1-4244-0787-3, Aug. 2007, Lyon, France. Wang Z. & C. Bovik, A. (2009) Mean squared error: love it or leave it? - A new look at signal fidelity measures, IEEE Signal Processing Magazine, Vol. 26, No. 1, Jan. 2009, pp. 98- 117. Wenger S. (2002). FMO: Flexible Macroblock Ordering, ITU-T JVT-C089, May 2002. Wenger, S. & Horowitz, M. (2002). Flexible MB Ordering – A New Error Resilience Tool for IP-Based Video, Proceedings of International Workshop on Digital Communications (IWDC’02), Sept. 2002, Capri, Italy. Wenger, S. (2003). H.264/AVC over IP, IEEE Transactions on Circuits and Systems for Video Technolology, Vol. 13, No. 7, Jul. 2003, pp. 645–656, 1051-8215. Wiegand, T.; Sullivan, G. J.; Bjøntegaard, G. & Luthra, A. (2003). Overview of the H.264/AVC video coding standard, IEEE Transactions on Circuits and Systems for Video Technolology, Vol. 13, No. 7, Jul. 2003, pp. 560–576, 1051-8215. Williams, D. & Shah, M. (1992). A Fast Algorithm for Active Contour and Curvature Estimation, GVCIP: Imag. Und., Vol. 55, No. 1, 1992, pp. 14-26. Yu, H.; Lin, Z. & Pan, F. (2005). Applications and improvement of H.264 in medical video compression, IEEE Transactions on Circuits and Systems I, Special issue on Biomedical Circuits and Systems: A New Wave of Technology, Vol. 52, No. 12, Dec. 2005, pp. 2707- 2716, 1549-8328. TowardsDiagnosticallyRobustMedicalUltrasoundVideoStreamingusingH.264 237 8. References Doukas, C. & Maglogiannis, I. (2008). Adaptive Transmission of Medical Image and Video Using Scalable Coding and Context-Aware Wireless Medical Networks, EURASIP Journal on Wireless Communications and Networking, Vol. 2008, Article ID 428397, 12 pages. doi:10.1155/2008/428397. Fielding, R.; Gettys, J.; Mogul, J.; Frystyk, H.; Masinter, L.; Leach, P. & Berners-Lee, T. (1999). Hypertext Transfer Protocol-HTTP/1.1., Internet Engineering Task Force, RFC 2616, 1999. H.264/AVC JM 15.1 Reference Software, Available: http://iphome.hhi.de/suehring/tml/. Handley, M.; Schulzrinne, H.; Schooler, E. & Rosenberg, J. (1999). SIP: Session Initiation Protocol, Internet Engineering Task Force, RFC 2543, Mar. 1999. Hennerici, M. & Neuerburg-Heusler, D. (1998). Vascular Diagnosis With Ultrasound, Thieme, 0865776032, 9780865776036, Stutgart - New York. Istepanian, R.H.; Laxminarayan, S. & Pattichis, C.S. (2006). M-Health: Emerging Mobile Health Systems, Springer, 0387265589, 9780387265582, New York. Joint Video Team of ITU-T and ISO/IEC JTC 1. (2003). Draft ITU-T Recommendation and Final Draft International Standard of Joint Video Specification (ITU-T Rec. H.264 | ISO/IEC 14496-10 AVC), Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG, JVTG050, Mar. 2003. Kyriacou, E.; Pattichis, M.S.; Pattichis, C.S.; Panayides, A. & Pitsillides, A. (2007). M-Health e-Emergency Systems: Current Status and Future Directions [Wireless corner], Antennas and Propagation Magazine, IEEE , Vol. 49, No. 1, Feb. 2007, pp. 216-231, 1045-9243. Lambert, P.; De Neve, W.; Dhondt, Y. & Van De Walle, R. (2006). Flexible macroblock ordering in H.264/AVC, Journal of Visual Communication and Image Representation, Vol. 17, No. 2, Apr. 2006, pp. 358-375, 10473203. Li, Z.G.; Pan, F.; Lim, K.P.; Feng, G.N.; Lin X. & Rahardaj, S. (2003). Adaptive basic unit layer rate control for JVT, JVT-G012, 7th meeting, Pattaya II, Thailand, 7-14, Mar. 2003. Loizou, C.P.; Pattichis, C.S.; Christodoulou, C.I.; Istepanian, R.S.H.; Pantziaris, M. & Nicolaides, A. (2005). Comparative evaluation of despeckle filtering in ultrasound imaging of the carotid artery, IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, Vol. 52, No. 10, Oct. 2005, pp. 1653-1669, 0885-3010. Loizou, C.P.; Pattichis, C.S.; Pantziaris, M. & Nicolaides, A. (2007). An integrated system for the segmentation of atherosclerotic carotid plaque, IEEE Transactions on Information Technology in Biomedicine, Vol. 11, No. 5, Nov. 2007, pp. 661-667, 1089-7771. Loizou, C.P. & Pattichis C.S. (2008). Despeckle filtering algorithms and Software for Ultrasound Imaging, Synthesis Lectures on Algorithms and Software for Engineering, Ed. Morgan & Claypool Publishers, 13: 9781598296204, USA. Panayides, A.; Pattichis, M. S. & Pattichis, C. S. (2008). Wireless Medical Ultrasound Video Transmission Through Noisy Channels, Proceedings of the 30 th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC’08), pp. 5326-5329, 1557-170X, Aug. 2008, Vancouver, Canada. Panayides, A.; Pattichis, M. S.; Pattichis, C. S.; Loizou, C. P.; Pantziaris, M. and Pitsillides, A. (2009). Robust and Efficient Ultrasound Video Coding in Noisy Channels Using H.264, to be published in Proceedings of the 31 st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC’09), Sep. 2009, Minnesota, U.S.A. Park S. & Miller, K. (1998). Random Number Generators: Good Ones Are Hard To Find, Communications of the ACM, Vol. 31, No. 10, Oct. 1988, pp. 1192 - 1201,0001-0782. Postel, J. (1980). User Datagram Protocol, Internet Engineering Task Force, RFC 768, 1980. Postel, J. (1981). Transmission Control Protocol, Internet Engineering Task Force, RFC 793, 1981. Rao, S. & Jayant, N. (2005). Towards high quality region-of-interest medical video over wireless networks using lossless coding and motion compensated temporal filtering, Proceedings of the fifth IEEE International Symposium on Signal Processing and Information Technology (ISSPIT’05), pp. 618-623, 0-7803-9313-9, Dec. 2005, Athens, Greece. Schulzrinne, H.; Casner, S.; Frederick, R. & Jacobson, V. (1996). RTP: A Transport Protocol for Real-Time Applications, Internet Engineering Task Force, RFC 1889, Jan. 1996. Schulzrinne, H.; Rao, A. & Lanphier, R. (1998). Real-Time Session Protocol (RTSP), Internet Engineering Task Force, RFC 2326, Apr. 1998. Tsapatsoulis N.; Loizou, C. & Pattichis, C. (2007). Region of Interest Video Coding for Low bit-rate Transmission of Carotid Ultrasound Videos over 3G Wireless Networks, Proceedings of the 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC’07), pp. 3717-3720, 978-1-4244-0787-3, Aug. 2007, Lyon, France. Wang Z. & C. Bovik, A. (2009) Mean squared error: love it or leave it? - A new look at signal fidelity measures, IEEE Signal Processing Magazine, Vol. 26, No. 1, Jan. 2009, pp. 98- 117. Wenger S. (2002). FMO: Flexible Macroblock Ordering, ITU-T JVT-C089, May 2002. Wenger, S. & Horowitz, M. (2002). Flexible MB Ordering – A New Error Resilience Tool for IP-Based Video, Proceedings of International Workshop on Digital Communications (IWDC’02), Sept. 2002, Capri, Italy. Wenger, S. (2003). H.264/AVC over IP, IEEE Transactions on Circuits and Systems for Video Technolology, Vol. 13, No. 7, Jul. 2003, pp. 645–656, 1051-8215. Wiegand, T.; Sullivan, G. J.; Bjøntegaard, G. & Luthra, A. (2003). Overview of the H.264/AVC video coding standard, IEEE Transactions on Circuits and Systems for Video Technolology, Vol. 13, No. 7, Jul. 2003, pp. 560–576, 1051-8215. Williams, D. & Shah, M. (1992). A Fast Algorithm for Active Contour and Curvature Estimation, GVCIP: Imag. Und., Vol. 55, No. 1, 1992, pp. 14-26. Yu, H.; Lin, Z. & Pan, F. (2005). Applications and improvement of H.264 in medical video compression, IEEE Transactions on Circuits and Systems I, Special issue on Biomedical Circuits and Systems: A New Wave of Technology, Vol. 52, No. 12, Dec. 2005, pp. 2707- 2716, 1549-8328. BiomedicalEngineering238 Contact-lessAssessmentofIn-vivoBodySignalsUsingMicrowaveDopplerRadar 239 Contact-less Assessment of In-vivo Body Signals Using Microwave DopplerRadar ShahrzadJalaliMazlouman,KouhyarTvakolian,AlirezaMahanfar,andBozenaKaminska X Contact-less Assessment of In-vivo Body Signals Using Microwave Doppler Radar Shahrzad Jalali Mazlouman, Kouhyar Tavakolian, Alireza Mahanfar and Bozena Kaminska Simon Fraser University, School of Engineering Science 8888 University Drive, V5A 1S6 Burnaby, BC, Canada 1. Introduction Every seven minutes in Canada, someone dies from heart disease or stroke. Cardiovascular disease (heart disease, diseases of the blood vessels and stroke) accounts for the death of more Canadians than any other disease (Heartandstroke, 2004). Early detection and treatment of symptoms and abnormalities can significantly decrease this rate. Therefore, the heart-related signals are the most important vital signals to monitor. For many years, extensive work has been devoted to finding low-cost, convenient, ubiquitous solutions to monitor heart signals in the everyday life. While these devices are beneficial, they have the disadvantage of requiring physical contact with the patient. Examples include chest straps to monitor the electrocardiogram (ECG) signal, gel for ultrasounds (echocardiography), heavy accelerometer sensor for seismocardiogram and electrodes for impedance cardiography (ICG) and oximetery. In addition, most of the existing methods require special expertise to use. The ideal solution would include a non-obtrusive method that can be used continuously and in everyday life without touching the patient and without requiring special expertise. From another point of view, seniors are becoming the fastest growing segment of the population in North America (Michahelles et al., 2004). This trend creates a new demand for health care. Availability of cost-efficient, wearable, non-invasive, real-time methods of monitoring body signals that can be used at home can save a significant fraction of costs for the health care system while providing efficient care to the elderly. Consequently, there is a growing demand for devices that allow remote monitoring of health related parameters and transferring the recorded data to a physician via telephone, internet, or cellular phone networks, in case of sensing any abnormalities or symptoms. Such non-invasive methods can also be beneficial for monitoring the effectiveness of treatment procedures for patients in the hospital or at home without requiring physical contact, thereby allowing long-term health care monitoring at almost no compromise in the patient’s mobility or ordinary lifestyle. As an example, in this chapter, a new method for monitoring of congestive heart failure patients using the radar technology is proposed. In addition, in-vivo body signals monitoring, in particular heart and breathing rate monitoring, 13 BiomedicalEngineering240 can provide safety in critical situations such as car driving, by initiating actions such as automatic control, stop and urgent call upon reading of an emergency call by the developed sensor (Michahelles et al., 2004). In this chapter, the basics of Microwave Doppler radar systems are investigated as a cost- efficient, non-invasive, and ubiquitous solution for continuous monitoring of in-vivo body signals; in particular, non-invasive sensing of cardiac, respiratory, and arterial movements. Microwave Doppler radar can detect motions and velocity based on Doppler effect; therefore, a variety of body signals including the mechanical motions of the chest because of heart beat (the radar seismocardiogram, R-SCG) as well as the blood flow velocity in major blood vessels can be monitored. Parameters such as heart-rate, hemodynamic parameters, blood flow velocity and respiration rate can be measured using these devices. Microwave Doppler radar systems do not require direct contact with the body and can function through blankets or clothing. Although laboratory demonstrations of the use of Doppler radar for cardiovascular and respiratory measurements date back to the late 1970’s and early 1980’s (Lin, 1975; Lin, 1979), cost-efficient, wearable body signal monitoring devices have not been reported until very recently; when implementation of low-cost, low-power, battery-operated devices is more feasible than ever by virtue of the availability and advances in high-integration technologies, signal processing techniques, and high-speed communication networks. Depending on the application, Microwave Doppler radar systems may use a continuous- wave or a time-gated radar signal. Continuous-wave Doppler radar have been shown to be comparable and even exceeding the conventional impedance cardiography methods for measuring the mechanical activity of the heart, as well as for measuring the heart-rate variability (HRV) (Staderini, 2002a). In fact, the derivative of the radar signal shows better correlations with the impedance cardiogram signal (ICG) (Thijs et al., 2005). Some signals have been confirmed to be more clear on the captured radar signal than on the ICG, for example, the opening of the atrium and the mitral valve (Thijs et al., 2005). A continuous Microwave Doppler radar based system was developed in the centre for integrative bio-engineering research (CiBER lab) of Simon Fraser University (Tavakolian et al, 2008a). The developed device is completely implemented on board and is the first reported device that can be used independently as a stand-alone system or can be connected to a PC. This device was tested to measure the heart and respiration rate of human subjects and demonstrated a noticeable accuracy of 91.35% for respiration rate, and 92.9% for heart rate. More importantly, this system was used to extract R-SCG signal as is discussed in the next sections. The structure of this book chapter is as follows. In Section 2, body signals that can potentially be measured using the Doppler radar system are introduced. Special emphasize has been given to a class of infrasonic cardiac signals, that radar extracted R-SCG signal belongs to it. In this section technical background such as the Doppler Effect, the radar system, and the ultra-wideband radar are discussed. In Section 3, details of the Microwave Doppler radar systems are discussed and analyzed and the related equations are derived. The building blocks are introduced and design specifications and requirements are calculated. Section 4 is devoted to practical implementation of the Microwave Doppler radar based system that was designed and implemented in the CiBER lab. 2. Background 2.1 Infrasonic Cardiac Signals Radar seismocardiogram (R-SCG) belongs to a category of cardiac signals that have their main components in the infrasonic range (less than 20 Hz) and reflect the mechanical function of the heart as a pump. During the past century, extensive research has been conducted on interpretation of these signals in terms of their relationship to cardiovascular dynamics and their possible application in cardiac abnormality diagnostics. Signals such as ballistocardiogram (BCG), seismocardiogram (SCG), apexcardiogram (ACG) and radar seismocardiogram reflect the displacement, velocity, or acceleration of the body in response to the heart beating. Different methods that were used to acquire these signals are shown in Fig. 1. R-SCG is recorded by contactless radar method, SCG and ACG are recorded by attaching sensors to the chest and BCG is recorded by measuring the changes of the center of mass of the whole body. The ACG acquisition is very similar to SCG, except for the recording site on the chest, which is the point of maximum impulse for ACG and the sternum for most SCG definitions, as is explained in the next section. A contactless method of recording ACG has also been proposed using microwave radar (Lin, 1979). The recorded signal morphology will vary with the method employed, but all the techniques appear to signal basically the same events in the cardiac cycle. The basic physiology behind all these signals are as follows: with each heart beat, blood rushes upward and strikes the aortic arch. The impact is great enough to give the whole body an upthrust. When the descending blood slows down, there is a rebound effect which gives the body a downthrust, not as intense as the earlier upthrust. These signals are normally recorded together with ECG thus, an understanding of the electromechanical performance of the heart can be achieved. In order to better understand the genesis of waves in R-SCG signal, for the first time in this writing, we study these signals in the same context and briefly investigate their simillarities and differences. Fig. 1. Different recording schemes for acquistion of infrasonic cardiac signals 2.1.1 Ballistocardiogram (BCG) The ballistocardiogram is caused by the change of the center of mass of body because of the blood circulation and can be recorded by noninvasive means. In the early 1930s Isaac Starr recognized that the BCG signals closely reflect the strength of myocardial contraction and [...]... Radar Sensing of Vital Signs IEEE Engineering in Medicine and Biology, 2002 Lubecke, V.; Boric-Lubecke, O & Beck, E (2002) A compact low-cost add-on module for Doppler radar sensing of vital signs using a wireless communications terminal Microwave Symp Digest, IEEE MTT-S Int., Vol.3, pp. 176 7- 177 0, 2002 McEwan, T E (1994) Ultra-wideband radar motion sensor.US Patents #5361 070 , 1994 McKay, W.P.S.; Gregon,... 22(1), pages 4-14, 1999 260 Biomedical Engineering Meyerhoff, N.J (20 07) Intrusion Detection by Ultra-Wide Bandwidth Radar Technologies for Homeland Security, IEEE Conf., pp.81-84, 16- 17 May 20 07 Michahelles, F.; Wicki, R & Schiele, B (2004) Less contact: Heart-rate Detection Without Even Touching the User, Proceedings of Wearable Computers (ISWC 2004) 8th Int Symp., vol.1, pp 4 -7, 31 Oct.-3 Nov 2004 Morgan,... Seismocardiography 29th IEEE EMBS, Lyon, France, August 20 07, pp 3954-3958 Chen, K.; Misra, D.; Wang, H.; Chuang, H & Postow, E (1986) An X-Band Microwave LifeDetection System Biomedical Engineering, IEEE Trans., BME-33, no .7, pp.6 97- 701, July 1986 Chia, M Y W.; Leong, S W.; Sim, C K & Chan, K M (2005) Through-wall UWB radar operating within FCC's mask for sensing heart beat and breathing rate Microwave... O.; Lubecke, V.M (20 07) Arctangent Demodulation With DC Offset Compensation in Quadrature Doppler Radar Receiver Systems, Microwave Theory and Techniques, IEEE Trans., Vol.55, No.5, pp.1 073 -1 079 , May 20 07 Salerno, D.; Zanetti, J (1990a) Seismocardiography: A new technique for recording cardiac vibration Concept, method and initial observation”, J Cardiovasc Technol, Vol 9, pp 111–1 17, 1990 Salerno, D.;... IEEE, vol 63, pp 1530, 1 975 Li J & Stoica, P (1996) Efficient mixed-spectrum estimation with applications to target feature extraction, Signal Processing, IEEE Trans., Vol.44, No.2, pp.281-295, Feb 1996 Lin, J.C.; Kiernicki, J.; Kiernicki, M & Wollschlaeger, P.B (1 979 ) Microwave Apexcardiography, Microwave Theory and Techniques, IEEE Trans., vol. 27, no.6, pp 618-620, Jun 1 979 Lohman, B.; Boric-Lubecke,... cardiovascular and respiratory measurements date back to the late 1 970 ’s and early 1980’s for the X-band (around 10GHz) (Lin, 1 975 ; Lin, 1 979 ; Chen et al., 1986) In mid-1980s, a frequency-modulated-continuous wave (FM-CW) system was developed to detect the vital signs of a wounded soldier in live fire situations at distances of up to 100 meters (Greneker, 19 97) Despite its severe limitations such as sensitivity... has emerged aiming to re-introduce SCG as a clinical instrument that can be used to noninvasively and inexpensively diagnose cardiac abnormalities (Akhbardeh et al., 20 07) (Castiglioni et al 20 07) (Tavakolian et al 2008b) 244 Biomedical Engineering Fig 4 Right: Positioning of different layers of tissues that the radar signal will go through Left: two cycles of the R-SCG, SCG and ECG signals (Tavakolian... ISSN 0165-1684, DOI: 10.1016/j.sigpro.2008. 07. 008 Norsworthy, S R.; Schreier, R., & Temes G C (1996) Delta-Sigma Data Conversions, WileyIEEE Press, ISBN: 978 - 078 0310452 Ngai, B.; Tavakolian, K.; Akhbardeh, A.; Blaber, A.P.; and Kaminska, B Comparative Analysis of Seismocardiogram Waves with the Ultra-Low Frequency Ballistocardiogram Submitted to 31st IEEE Engineering in Medicine and Biology conference... Int., Vol.1, pp. 175 - 178 , 2001 Dutta, P.K.; Arora, A.K.& Bibyk, S.B (2006) Towards radar-enabled sensor networks 5th Int Conf on Information Processing in Sensor Networks (IPSN), Nashville, Tennessee, USA, April 2006 FCC (2002), Federal Communications Commission, Revision of part 15 of the commission’s rules regarding ultra wideband transmission systems April 2002, www.fcc.gov/Bureaus /Engineering _Technology/Orders/2002/fcc02048.pdf... Development of a Novel Contactless Mechanocardiograph Device Int J Telemedicine Appl., 2008:436 870 Tavakolian, K.; Vaseghi, A.; Kaminska, B (2008b) "Improvement of ballistocardiogram processing by inclusion of respiration information" Journal of Physiological Measurement, Institute of Physics, 29 (2008) 77 1 -78 1 Thansandote, A.; Stuchly, S.S.; Smith A.M (1983) Monitoring variations of biological impedances . 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC’ 07) , pp. 371 7- 372 0, 978 -1-4244- 078 7-3, Aug. 20 07, Lyon, France. Wang Z. & C. Bovik, A. (2009). 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC’ 07) , pp. 371 7- 372 0, 978 -1-4244- 078 7-3, Aug. 20 07, Lyon, France. Wang Z. & C. Bovik, A. (2009). 0.11 153 4 Negligible 34.88 508 30.69 1 57 36.06 156 1.18 352 5. 37 36.51 960 33.01 302 38.65 301 2.14 659 5.64 37. 47 1642 33. 67 562 40 .77 561 3.30 1081 7. 10 38.04 2554 35.6 960 42.56 959 4.52

Ngày đăng: 21/06/2014, 18:20

TỪ KHÓA LIÊN QUAN