在這篇論文中，我們提出一個有低運算複雜度，有效率使用記憶體，與有延展能力的混合式小波視訊編碼器。 它可用在位元傳輸率較低，記憶體有侷限，以及需要延展性的視訊應用上。 這個視訊編碼器包含二個主要的模組。 一個是3-D lifting-based整數小波轉換模組，它的功用是將一組Video frames的資訊做轉換使其資訊的分佈更為集中。 另外一個是Modified 3-D listless zero-tree coding模組，它的功用是將前面已轉換好的Video frames做進一步的壓縮。 此外當Modified 3-D listless zero-tree coding模組在執行時，我們採用3-D asymmetric parent-child relations 來讓挑選3-D wavelet coefficients的動作變得更有效率。 我們所提出的視訊編碼器有下列優點：低運算複雜度，有效率地使用記憶體，以及有rate, spatial, and temporal的延展性。 為了要評估這個被提出的視訊編碼器，我們將它與Lin和Burgess所提出的3-D LZC視訊編碼器做比較。 我們做了完整的實驗，結果顯示我們所提出的視訊編碼器的PSNR值會優於3-D LZC視訊編碼器。

In this paper, we propose a hybrid wavelet-based video codec for low bit-rate, memory-constrained, and scalable video applications. The hybrid video codec consists of two main modules, the 3-D (temporal and 2-D spatial) lifting-based integer wavelet transform module that performs an energy compaction of a group of video frames and the modified 3-D listless zero-tree coding module that further codes the transformed video frames. When executing the modified 3-D listless zero-tree coding module, the 3-D asymmetric parent-child relations are used for sorting the 3-D wavelet coefficients more effectively. Advantageous features of the hybrid video codec include low computational complexity, memory-efficient, rate, spatial, and temporal scalability. To evaluate the proposed video codec, we have compared it with the 3-D LZC video codec proposed by Lin and Burgess. Extensive simulations have been conducted. The simulation results show that a significant gain in PNSR is obtained with this video codec compared to the 3-D LZC video codec.

[1] M. D. Adams and F. Kossentini, “Reversible integer-to-integer wavelet transforms for image compression: performance evaluation and analysis,” IEEE Transactions on Image Processing, Vol. 9, No. 6, June 2000, pp. 1010-1024.
[2] A. R. Calderbank, I. Daubechies, W. Sweldens, and B. L. Yeo, “Wavelet transforms that map integers to integers,” Applied and Computational Harmonic Analysis, Vol. 5, July 1998, pp. 332-369.
[3] Y. Chen and W. A. Pearlman, “Three-dimensional subband coding of video using the zero tree method,” SPIE Visual Communications and Image Processing, Vol. 2727, March 1996, pp. 1302-1312.
[4] P. L. Dragotti, G. Poggi, and A. R. P. Ragozini, “Compression of multispectral images by three-dimensional SPIHT algorithm,” IEEE Transaction on Geoscience and Remote Sensing, Vol. 38, January 2000, pp. 416-428.
[5] Chao He, Jianyu Dong, Yuan F. Zheng, and Zhigang Gao, “Optimal 3-D coefficient tree structure for 3-D wavelet video coding,” IEEE Transactions on Circuits and Systems for Video Technology, Vol. 13, No. 10, October 2003, pp. 961-972.
[6] ISO/IEC 11172-2, “Information Technology - Coding of Moving Pictures and Associated Audio for Digital Storage Media up to about 1.5 Mbps - Part 2: Coding of Moving Picture Information,” International Organization for Standardization, 1991.
[7] ISO/IEC 13818-2, “Information Technology – Generic Coding of Moving Pictures and Associated Audio Information - Part 2: Video,” International Organization for Standardization, 1994.
[8] ISO/IEC 14496-2, “Information Technology - Generic Coding for Audio-visual Objects - Part 2: Visual,” MPEG-4 Video Coding Standard, October 1998.
[9] ITU-T Draft Recommendation H.263, “Video coding for low bit-rate communications,” December 1995.
[10] B. Kim and W. A. Pearlman, “An embedded wavelet video coder using three-dimensional set partitioning in hierarchical trees (SPIHT),” IEEE Data Compression Conference, March 1997, pp. 251-260.
[11] B. Kim and W. A. Pearlman, “Fast color-embedded video coding with SPIHT,” March 1998, [Online] Available: http://www.cipr.rpi.edu/~pearlman/papers.
[12] B. Kim, Z. Xiong, and W. A. Pearlman, “Low bit-rate scalable video coding with 3-D set partitioning in hierarchical trees (3-D SPIHT),” IEEE Transactions on Circuits and Systems for Video Technology, Vol. 10, December 2000, pp. 1374-1387.
[13] W. Lin and N. Burgess, “3-D listless zerotree coding for low-bit rate video,” IEEE International Conference on Image Processing, Vol. 3, 1999, pp. 762-766.
[14] W. Lin and N. Burgess, “Listless zerotree coding for color images,” Record 32nd Asilomar Conference on Signals, Systems, and Computers, Vol. 1, 1998, pp. 231-235.
[15] A. Said and W. A. Pearlman, “A new fast and efficient image codec based on set partitioning in hierarchical trees,” IEEE Transactions on Circuits and Systems for Video Technology, Vol. 6, June 1996, pp. 243-250.
[16] A. Said and W. A. Pearlman, “An image multiresolution representation for lossless and lossy compression,” IEEE Transactions on Image Processing, Vol. 5, September 1996, pp. 1303-1310.
[17] A. Said and W. A. Pearlman, “Image compression using the spatial-orientation tree,” IEEE International Symposium on Circuits and Systems, May 1993, pp. 279-282.
[18] J. M. Shapiro, “Embedded image coding using zerotrees of wavelets coefficients,” IEEE Transaction on Signal Processing, Vol. 41, No. 12, December 1993, pp. 3445-3463.
[19] W. Sweldens, “The lifting scheme: A construction of second generation wavelets,” Society for Industrial and Applied Mathematics Journal on Mathematical Analysis, Vol. 29, No. 2, 1997, pp. 511-546.
[20] W. Sweldens, “The lifting scheme: A custom-design construction of biorthogonal wavelets,” Applied and Computational Harmonic Analysis, Vol. 3, November 1996, pp. 186-200.
[21] W. Sweldens, “The lifting scheme: A new philosophy in biorthogonal wavelet constructions,” Proceedings of the SPIE, Vol. 2569, 1995, pp. 68-79.
[22] A. M. Tekalp, “Digital Video Processing,” Englewood Cliffs: Prentice-Hall Signal Processing Series, 1995.
[23] Telecommunication Networks Group, Resources in Wireless Networking, http://www.tkn.tu-berlin.de/research/evalvid/qcif.html.
[24] J. Vass, B. Chai, and X. Zhuang, “3-D SLCCA-a hightly scalable very low bit-rate software-only wavelet video codec,” IEEE 2nd Workshop Multimedia Signal Processing, 1998, pp. 474-479.
[25] A. Zandi, J. D. Allen, E. L. Schwartz, and M. Boliek, “CREW: Compression with reversible embedded wavelets,” IEEE Data Compression Conference, March 1995, pp. 212-221.