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Encryption Scheme for MPEG-4 Media Transmission Exploiting Frame Dropping

대역폭 감소를 적용한 MPEG-4 미디어 전송시의 암호화 기법 연구

  • 신동규 (세종대학교 컴퓨터공학과) ;
  • 신동일 (세종대학교 컴퓨터공학과) ;
  • 박세영 (세종대학교 컴퓨터공학과)
  • Published : 2008.12.31

Abstract

According to the network condition, the communication network overload could be occurred when media transmitting. Many researches are being carried out to lessen the network overload, such as the filtering, load distributing, frame dropping and many other methods. Among these methods, one of effective method is frame dropping that reduces specified video frames for bandwidth diminution. B frames are dropped and then I, P frames are dropped according to dependency among the frames in frame dropping. This paper proposes a scheme for protecting copyrights by encryption, when we apply frame dropping to reduce bandwidth of media following MPEG-4 file format. We designed two kinds of frame dropping: first one stores and then sends the dropped files and the other drops frames in real-time when transmitting. We designed three kinds of encryption methods in which DES algorithm is used to encrypt MPEG-4 data: macro block encryption in I-VOP, macro block and motion vector encryption in P-VOP, and macro block and motion vector encryption in I, P-VOP. Based on these three methods, we implemented a digital right management solution for MPEG-4 data streaming. We compared the results of dropping, encryption, decryption and quality of video sequences to select an optimal method, and there is no noticeable difference between the video sequences recovered after frame dropping and the ones recovered without frame dropping. The best performance in encryption and decryption of frames was obtained when we apply the macro block and motion vector encryption in I, P-VOP.

미디어의 전송시 네트워크의 상황에 따라 통신망의 과부하가 발생할 수 있으며, 이를 줄이기 위해서 필터링, 부하 분산기법, 막힘 제어 기법, 프레임 드로핑 등의 많은 연구가 진행되었다. 이들 중 효과적인 방법은 동영상의 비트율을 조절하기 위해 특정 비디오 프레임을 제거함으로써 대역폭의 감소를 가능하게 하는 프레임 드로핑(Frame dropping)이다. 프레임 드로핑은 프레임 간의 종속성이 가장 적은 B 프레임을 먼저 제거하고 종속성의 관계에 따라 I, P 프레임 순서대로 제거한다. 본 논문에서는 MPEG-4 미디어의 전송에 프레임 드로핑을 적용 하였으며 이때 암호화를 통하여 저작권을 보호할 수 있는 방법을 제안한다. 이를 위하여 서버에 저장되어있는 프레임 드로핑 이 이미 적용된 파일을 클라이언트에게 전송하는 방법과 서버에 저장되어있는 미디어 파일을 클라이언트에게 전송시 실시간으로 프레임 드로핑하는 두 가지 방법을 설계 구현 하였다. MPEG-4 데이터의 암호화에는 3가지 방법을 제안하였다: I-VOP내의 매크로 블록(Macro block) 암호화, P-VOP내의 매크로 블록과 모션벡터 암호화(Motion Vector), I-VOP내의 매크로블록과 P-VOP내의 모션벡터 암호화. MPEG-4 미디어의 전송시, 최적의 방법을 선택하기 위해 드로핑, 암호화, 복호화 및 영상의 품질을 비교하였으며 드로핑 후에도 원래의 영상과 큰 차이가 없었다. 암호화와 복호화에서는 I-VOP와 P-VOP를 모두 암호화 하였을 때가 가장 성능이 좋았다.

Keywords

References

  1. http://ko.wikipedia.org/wiki/MPEG-4
  2. C. C. Bisdikian and B. V. Patel, “Issues on Movie Allocation in Distributed Video-on-Demand Systems,” Proc. IEEE International Conference on Communications, IEEE Communications Society, New York, pp.250-255, 1995 https://doi.org/10.1109/ICC.1995.525173
  3. L. Xu and J. Helzer, “Media Streaming via TFRC: An Analytical Study of the Impact of TFRC on User-Perceived Media Quality,” IEEE INFOCOM, 2006 https://doi.org/10.1109/INFOCOM.2006.244
  4. S. Floyd, M. Handley, J. Padhye and J. Widmer, “Equation-Based Congestion Control for UnicastApplications,” ACM SIGCOMM, 2000
  5. “Proposed new text of IPMP FAQ,” ISO/IEC JTC/SC29/WG11 M8141 Jeju 2002
  6. “MPEG-4 Intellectual Property Management & Protection (IPMP) Overview & Application Document,” ISO/IEC/SC29/WG11/N2614 MPEG 98, December, 1998
  7. Ming-Ting Sun and Amy R. Reibman, Compressed Video over Networks, Marcel Dekker, Inc., 2001
  8. King N. Ngan, Chi W. Yap and Keng T. Tan, Video Coding for Wireless Communication Systems, Marcel Dekker, Inc., 2001
  9. 정홍섭, 박규석 “네트워크 부하 기반 프레임 생략 전송 알고리즘”, 멀티미디어학회 논문지, 제6권 제7호, December, 2003
  10. L. Delgrossi, C. Halstrick, D. hehmann, R. G. Herrtwich, O. Krone, J. Sandvoss and C. Vogt, “Media Scaling for Audiovisual Communication with the Heidelberg Transport System,” Proceedings ACM Multimedia, 1993
  11. W. Zeng and B. LIU, “Rate Shaping by Block Dropping for Transmission of MPEG Precoded Video over Channels of Dynamic Bandwidth,” Multimedia 96 Processing, The Fourth ACM Internatnional Multimedia Conference, Boston Ma. pp.129-140, 1996
  12. J. Sandvoss, J. Winkler and H. Witting, “Network Layer Scaling : Congestion Control in Multimedia Communication with Heterogeneous Networks and Recivers,” IBM European Networking Center, Heidelberg, 1994
  13. Jae-Gon Kim, Yong Wang, Shih-Fu Chang, Kyeongok Kang and Jinwoong Kim “Description of utility function based optimum transcoding,” ISO/IEC JTC1/SC29/WG11M8319, Fairfax, May, 2002
  14. W. Li, J. Ohm, M. V. Schaar, H. Jiang and S. Li, MPEG-4 Video verification model ver. 18.0, ISO/ IEC/ JTC1/ SC29/WG11/ N3908, 2001
  15. H. Radha, Y. Chen, K. Parthasarathy and R. Cohen, “Scalable internet video using MPEG-4,” Signal Processing: Image Communication, Vol.15, pp.95-126, 1999 https://doi.org/10.1016/S0923-5965(99)00026-0
  16. I. Agi and L. Gong, “An Empirical Study of Mpeg Video Transmissions,” In Proc. of the Internet Society Symposium on Network and Distributed System Security, San Diego, CA, pp.137-144, Feb., 1996 https://doi.org/10.1109/NDSS.1996.492420
  17. T. B. Maples and G. A. Spanos, “Performance Study of a Selective Encryption Scheme for the Security of Networked, Real-time Video,” Proc. of 4th International Conf. on Computer Communications and Networks, Las Vegas, Nevada, Sep., 1995
  18. L. Tang, “Methods for Encrypting and Decrypting MPEG Video Data Efficiently,” Proc. of 4th ACM International Multimedia Conference, Boston MA, pp.219-230, Nov., 1996
  19. L. Qiao and K. Nahrstedt, “A New Algorithm for MPEG Video Encryption,” Proc. of The First International Conference on Imaging Science, Systems, and Technology(CISST'97), Las Vegas, Nevada, pp.21-29, July, 1997
  20. C. Yuan, B. B. Zhu, Y. Wang, S. Li and Y. Zhong, “Efficient and Fully Scalable Encryption for MPEG-4 FGS,” IEEE Int. Symp. Circuits and Systems, May, 2003 https://doi.org/10.1109/ISCAS.2003.1206050
  21. Y. Mao and M. Wu, “A Joint Signal Processing and Cryptographic Approach to Multimedia Encryption,” IEEE Trans. on Image Processing, Vol.15, No.7, pp.2061-2075, July, 2006 https://doi.org/10.1109/TIP.2006.873426
  22. S. Lian, Z. Liu, Z. Ren and Z. Wang, “Selective Video Encryption Based on Advanced Video Coding,” PCM 2005, Part II, Springer LNCS, Vol.3768, pp.281-290, 2005 https://doi.org/10.1007/11582267_25
  23. A. Said, “Measuring the strength of partial encryption schemes,” proceedings of 2005 IEEE International Conference on Image Processing (ICIP 2005), 11-14 Sept., Vol.2, pp.1126-1129 https://doi.org/10.1109/ICIP.2005.1530258
  24. “QuickTime File Format,” Apple Computer, June, 2000
  25. “Information technology-Coding of audio-visual objectspart 1:System ISO/IEC14496-1:2001,” ISO/IEC/SC29/WG11, 2001
  26. 김건희, 신동규, 신동일 “MPEG-4 비디오 스트림의 디지털 저작권 관리를 위한 암호화 기법의 연구”, 정보처리학회논문지, April, 2005
  27. Data Encryption Standard (DES), FIPS PUB 46-3, Oct., 25, 1999

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