by Man-Ching Auyeung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 86-93). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Transform coding and the JPEG scheme --- p.2 / Chapter 1.2 --- Motivation --- p.5 / Chapter 1.3 --- Thesis outline --- p.6 / Chapter 2 --- MED and DC Coefficient Restoration scheme --- p.8 / Chapter 2.1 --- Introduction --- p.8 / Chapter 2.2 --- MED and DC Coefficient Restoration scheme --- p.10 / Chapter 2.2.1 --- Definition --- p.10 / Chapter 2.2.2 --- Existing schemes --- p.11 / Chapter 2.3 --- DC Coefficient Restoration scheme using block selection scheme --- p.14 / Chapter 2.4 --- Joint optimization technique --- p.16 / Chapter 2.4.1 --- Lagrange multiplier method --- p.17 / Chapter 2.4.2 --- Algorithm description --- p.18 / Chapter 2.5 --- Experimental results --- p.20 / Chapter 2.6 --- Summary --- p.32 / Chapter 3 --- Low Frequency Walsh Transform Coefficient Restoration scheme --- p.34 / Chapter 3.1 --- Introduction --- p.34 / Chapter 3.2 --- Restoration of low frequency coefficient using Walsh transform --- p.35 / Chapter 3.3 --- Selection of quantization table optimized for Walsh transform --- p.37 / Chapter 3.3.1 --- Image model used --- p.39 / Chapter 3.3.2 --- Infinite uniform quantization --- p.40 / Chapter 3.3.3 --- Search for an optimized quantization matrix --- p.42 / Chapter 3.4 --- Walsh transform-based LFCR scheme --- p.44 / Chapter 3.5 --- Experimental results --- p.46 / Chapter 3.6 --- Summary --- p.56 / Chapter 4 --- Low Frequency DCT Coefficient Prediction --- p.57 / Chapter 4.1 --- Introduction --- p.57 / Chapter 4.2 --- Low Frequency Coefficient Prediction scheme with negligible side information --- p.58 / Chapter 4.2.1 --- Selection of threshold --- p.63 / Chapter 4.2.2 --- Representation of the AC component --- p.63 / Chapter 4.3 --- Experimental results --- p.67 / Chapter 4.4 --- Summary --- p.84 / Chapter 5 --- Conclusions --- p.86 / Appendix A --- p.89 / Bibliography --- p.90

by Tse, Fu Wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 155-[63]). / Acknowledgment --- p.iii / Abstract --- p.iv / Contents --- p.vi / List of Tables --- p.x / List of Figures --- p.xii / Notations --- p.xvii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- DC coefficient restoration --- p.1 / Chapter 1.2 --- Model based image compression --- p.5 / Chapter 1.3 --- The minimum edge difference criterion and the existing estima- tion schemes --- p.7 / Chapter 1.3.1 --- Fundamental definitions --- p.8 / Chapter 1.3.2 --- The minimum edge difference criterion --- p.9 / Chapter 1.3.3 --- The existing estimation schemes --- p.10 / Chapter 1.4 --- Thesis outline --- p.14 / Chapter 2 --- A mathematical description of the DC coefficient restoration problem --- p.17 / Chapter 2.1 --- Introduction --- p.17 / Chapter 2.2 --- Mathematical formulation --- p.18 / Chapter 2.3 --- Properties of H --- p.22 / Chapter 2.4 --- Analysis of the DC coefficient restoration problem --- p.22 / Chapter 2.5 --- The MED criterion as an image model --- p.25 / Chapter 2.6 --- Summary --- p.27 / Chapter 3 --- The global estimation scheme --- p.29 / Chapter 3.1 --- Introduction --- p.29 / Chapter 3.2 --- the global estimation scheme --- p.30 / Chapter 3.3 --- Theory of successive over-relaxation --- p.34 / Chapter 3.3.1 --- Introduction --- p.34 / Chapter 3.3.2 --- Gauss-Seidel iteration --- p.35 / Chapter 3.3.3 --- Theory of successive over-relaxation --- p.38 / Chapter 3.3.4 --- Estimation of optimal relaxation parameter --- p.41 / Chapter 3.4 --- Using successive over-relaxation in the global estimation scheme --- p.43 / Chapter 3.5 --- Experiments --- p.48 / Chapter 3.6 --- Summary --- p.49 / Chapter 4 --- The block selection scheme --- p.52 / Chapter 4.1 --- Introduction --- p.52 / Chapter 4.2 --- Failure of the minimum edge difference criterion --- p.53 / Chapter 4.3 --- The block selection scheme --- p.55 / Chapter 4.4 --- Using successive over-relaxation with the block selection scheme --- p.57 / Chapter 4.5 --- Practical considerations --- p.58 / Chapter 4.6 --- Experiments --- p.60 / Chapter 4.7 --- Summary --- p.61 / Chapter 5 --- The edge selection scheme --- p.65 / Chapter 5.1 --- Introduction --- p.65 / Chapter 5.2 --- Edge information and the MED criterion --- p.66 / Chapter 5.3 --- Mathematical formulation --- p.70 / Chapter 5.4 --- Practical Considerations --- p.74 / Chapter 5.5 --- Experiments --- p.76 / Chapter 5.6 --- Discussion of edge selection scheme --- p.78 / Chapter 5.7 --- Summary --- p.79 / Chapter 6 --- Performance Analysis --- p.81 / Chapter 6.1 --- Introduction --- p.81 / Chapter 6.2 --- Mathematical derivations --- p.82 / Chapter 6.3 --- Simulation results --- p.92 / Chapter 6.4 --- Summary --- p.96 / Chapter 7 --- The DC coefficient restoration scheme with baseline JPEG --- p.97 / Chapter 7.1 --- Introduction --- p.97 / Chapter 7.2 --- General specifications --- p.97 / Chapter 7.3 --- Simulation results --- p.101 / Chapter 7.3.1 --- The global estimation scheme with the block selection scheme --- p.101 / Chapter 7.3.2 --- The global estimation scheme with the edge selection scheme --- p.113 / Chapter 7.3.3 --- Performance comparison at the same bit rate --- p.121 / Chapter 7.4 --- Computation overhead using the DC coefficient restoration scheme --- p.134 / Chapter 7.5 --- Summary --- p.134 / Chapter 8 --- Conclusions and Discussions --- p.136 / Chapter A --- Fundamental definitions --- p.144 / Chapter B --- Irreducibility by associated directed graph --- p.146 / Chapter B.1 --- Irreducibility and associated directed graph --- p.146 / Chapter B.2 --- Derivation of irreducibility --- p.147 / Chapter B.3 --- Multiple blocks selection --- p.149 / Chapter B.4 --- Irreducibility with edge selection --- p.151 / Chapter C --- Sample images --- p.153 / Bibliography --- p.155

Firstly, the characteristics of HD videos are studied quantitatively. The results show that HD videos distinguish from other lower resolution videos by higher spatial correlation and special power spectral density (PSD), mainly distributed along the vertical and horizontal directions. / Secondly, two techniques for HD video coding are developed based on the aforementioned analysis results. To exploit the spatial property, 2D order-16 transforms are proposed to code the higher correlated signals more efficiently. Specially, two series of 2D order-16 integer transforms, named modified integer cosine transform (MICT) and non-orthogonal integer cosine transform (NICT), are studied and developed to provide different trade-offs between the performance and the complexity. Based on the property of special PSD, parametric interpolation filter (PIF) is proposed for motion-compensated prediction (MCP). Not only can PIF track the non-stationary statistics of video signals as the related work shows, but also it represents interpolation filters by parameters instead of individual coefficients, thus solving the conflict of the accuracy of coefficients and the size of side information. The experimental results show the proposed two coding techniques significantly outperform their equivalents in the state-of-the-art international video coding standards. / Thirdly, interlaced HD videos are studied, and to satisfy different delay constraints, two real-time de-interlacing algorithms are proposed specially for H.264 coded videos. They adapt to local activities, according to the syntax element (SE) values. Accuracy analysis is also introduced to deal with the disparity between the SE values and the real motions and textures. The de-interlacers provide better visual quality than the commonly used ones and can de-interlace 1080i sequences in real time on PCs. / Today, High-Definition (HD) videos become more and more popular with many applications. This thesis analyzes the characteristics of HD videos and develops the appropriate coding and processing techniques accordingly for hybrid video coding. / Dong, Jie. / Adviser: King Ngi Ngan. / Source: Dissertation Abstracts International, Volume: 72-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 153-158). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Tan, Min. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 35-36). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Previous Work --- p.1 / Chapter 1.2 --- Motivation --- p.2 / Chapter 1.3 --- Contributions --- p.2 / Chapter 1.4 --- Thesis Organization --- p.3 / Chapter 2 --- Linear Network Coding Basics --- p.5 / Chapter 2.1 --- Formulation and Example --- p.5 / Chapter 2.2 --- Some Notations --- p.9 / Chapter 3 --- A Unified Framework --- p.13 / Chapter 3.1 --- Generic Network Codes Revisited --- p.13 / Chapter 3.2 --- A Unified Framework --- p.24 / Chapter 3.3 --- Simplified Proofs --- p.29 / Chapter 4 --- Conclusion --- p.33 / Bibliography --- p.35

Mi, Wengang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 80-85). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Path loss and fading channel --- p.2 / Chapter 1.2 --- Relay Channel --- p.4 / Chapter 1.3 --- Power allocation --- p.6 / Chapter 1.4 --- Network coding --- p.8 / Chapter 1.5 --- Outline of the thesis --- p.8 / Chapter 2 --- Background Study --- p.10 / Chapter 2.1 --- Cooperative communication --- p.10 / Chapter 2.1.1 --- User cooperation diversity --- p.11 / Chapter 2.1.2 --- Cooperative diversity --- p.14 / Chapter 2.1.3 --- Coded cooperation --- p.18 / Chapter 2.2 --- Power control and resource allocation in cooperative communication --- p.19 / Chapter 2.3 --- Network coding --- p.21 / Chapter 3 --- Power allocation in DF system --- p.24 / Chapter 3.1 --- Introduction --- p.24 / Chapter 3.2 --- System Model --- p.25 / Chapter 3.3 --- BER analysis with power allocation --- p.27 / Chapter 3.3.1 --- BER analysis of single relay system --- p.27 / Chapter 3.3.2 --- Generalization for N-relay cooperation system --- p.30 / Chapter 3.4 --- Approximation --- p.31 / Chapter 3.5 --- Conclusion --- p.37 / Chapter 4 --- Network coding cooperation --- p.38 / Chapter 4.1 --- Introduction --- p.38 / Chapter 4.2 --- System model --- p.39 / Chapter 4.3 --- Performance analysis --- p.44 / Chapter 4.3.1 --- Network coding cooperation --- p.47 / Chapter 4.3.2 --- Conventional repetition cooperation --- p.48 / Chapter 4.3.3 --- Simulation result --- p.49 / Chapter 4.4 --- More nodes with network coding --- p.52 / Chapter 4.4.1 --- System model: to be selfish or not --- p.53 / Chapter 4.4.2 --- Performance analysis --- p.56 / Chapter 4.4.3 --- Simulation result --- p.62 / Chapter 4.5 --- Further discussion --- p.63 / Chapter 5 --- Conclusion --- p.64 / Chapter A --- Equation Derivation --- p.66 / Chapter A.l --- Proof of proposition 1 --- p.66 / Chapter A.2 --- Generalized solution --- p.68 / Chapter A.3 --- System outage probability of generous scheme --- p.69 / Chapter A.4 --- System outage probability of selfish scheme --- p.74 / Bibliography --- p.79

Chen, Junyu. / Thesis M.Phil. Chinese University of Hong Kong 2014. / Includes bibliographical references (leaves 56-61). / Abstracts also in Chinese. / Title from PDF title page (viewed on 25, October, 2016).

Fong, Lik Hang Silas. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 40). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Linear Network Code --- p.4 / Chapter 2.1 --- Linear Network Code without Link Failures --- p.4 / Chapter 2.1.1 --- Linear Multicast and Linear Broadcast --- p.6 / Chapter 2.2 --- Linear Network Code with Link Failures --- p.8 / Chapter 2.2.1 --- Static Linear Multicast and Static Linear Broadcast --- p.9 / Chapter 3 --- Variable-Rate Linear Network Coding --- p.11 / Chapter 3.1 --- Variable-Rate Linear Network Coding without Link Failures --- p.11 / Chapter 3.1.1 --- Problem Formulation --- p.11 / Chapter 3.1.2 --- Algorithm and Analysis --- p.12 / Chapter 3.2 --- Variable-Rate Linear Network Coding with Link Failures --- p.23 / Chapter 3.2.1 --- Problem Formulation --- p.23 / Chapter 3.2.2 --- Algorithm and Analysis --- p.23 / Chapter 3.3 --- The Maximum Broadcast Rate of Linear Network Code --- p.28 / Chapter 4 --- Conclusion --- p.38 / Bibliography --- p.40

Abstract not available

The two main goals of this research are to study the implementation aspects of space-time turbo trellis codes (ST Turbo TC) and to develop efficient simulation methods for space-time and turbo coded systems using the importance sampling (IS) technique. The design of ST Turbo TC for improving the bandwidth efficiency and the reliability of wireless communication networks, which is based on the turbo structure, has been proposed in the literature. To achieve memory savings and reduce the decoding delay, this thesis proposes a simplified ST Turbo TC decoder using a sliding window (SW) technique. Different window sizes are employed and investigated. Through computer simulation, the optimum window sizes are determined for various system configurations. The effect of finite word length representation on the performance of ST Turbo TC is then studied. Simulation results show that ST Turbo TC is feasible for finite word length representation without significant degradation in the frame error rate performance. The optimum word length configurations are defined for all quantities external and internal to the ST Turbo TC decoder. For complex communication systems such as space-time codes and turbo codes, computer simulation is in fact the useful approach to obtain the estimated performance. To overcome the lengthy run-time requirements of the conventional Monte-Carlo (MC) method, this thesis introduces importance sampling simulation methods that accurately estimate the performances of turbo codes and space-time codes including orthogonal space-time block codes (OSTBC) and concatenated OSTBC. It is demonstrated that the proposed methods require much smaller sample sizes to achieve the same accuracy required by a conventional MC estimator. / Doctor of Philosophy (PhD)

Physical-Layer Network Coding (PNC) is a promising technique that has great potentials for improving the achievable data rates of end-to-end flows through higher packet transmission rates, thereby increasing the overall network throughput. In this thesis, we study the performance of the PNC transmission techniques for unidirectional end-to-end flows in multi-hop wireless networks, and compare it with that of the traditional transmission techniques. We first derive the bit-error rate (BER) that the PNC transmission technique achieves. Then, using the derived BER, we evaluate and quantify the achievable network throughput under both the PNC transmission technique and the traditional technique, where the network throughput is measured as the aggregate/sum of all end-to-end flows' achievable data rates in the wireless network. Using extensive simulations, we show that PNC increases the overall achievable end-to-end flow throughput in multi-hop wireless networks, especially under medium to high signal-to-noise ratios. / Graduation date: 2012