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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

A study of the transmission of VBR encoded video over ATM networks.

January 1997 (has links)
by Ngai Li. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 66-69). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Video Compression and Transport --- p.2 / Chapter 1.2 --- Research Contributions --- p.6 / Chapter 1.2.1 --- Joint Rate Control of VBR Encoded Video --- p.6 / Chapter 1.2.2 --- Transporting VBR Video on LB Controlled Channel --- p.7 / Chapter 1.3 --- Organization of Thesis --- p.7 / Chapter 2 --- Preliminary --- p.9 / Chapter 2.1 --- Statistical Characteristics of MPEG-1 Encoded Video --- p.9 / Chapter 2.2 --- Temporal and Spatial Smoothing --- p.14 / Chapter 2.2.1 --- Temporal Smoothing --- p.14 / Chapter 2.2.2 --- Spatial Smoothing --- p.15 / Chapter 2.3 --- A Single Source Control-Theoretic Framework for VBR-to-CBR Video Adaptation --- p.16 / Chapter 3 --- Joint Rate Control of VBR Encoded Video --- p.19 / Chapter 3.1 --- Analytical Models --- p.21 / Chapter 3.2 --- Analysis --- p.27 / Chapter 3.2.1 --- Stable Region --- p.29 / Chapter 3.2.2 --- Final Value of the State Variables --- p.33 / Chapter 3.2.3 --- Peak Values of Buffer-occupancy Deviation and Image- quality Fluctuation --- p.35 / Chapter 3.2.4 --- SAE of Buffer-occupancy Deviation and Image-quality Fluc- tuation --- p.42 / Chapter 3.3 --- Experimental Results --- p.43 / Chapter 3.4 --- Concluding Remarks --- p.48 / Chapter 4 --- Transporting VBR Video on LB Controlled Channel --- p.50 / Chapter 4.1 --- Leaky Bucket Access Control --- p.51 / Chapter 4.2 --- Greedy Token-usage Strategy --- p.53 / Chapter 4.3 --- Non-greedy Token-usage Strategy --- p.57 / Chapter 4.4 --- Concluding Remarks --- p.60 / Chapter 5 --- Conclusions --- p.62 / Chapter 5.1 --- Joint Rate Control of Multiple VBR Videos --- p.62 / Chapter 5.2 --- LB Video Compression --- p.63 / Chapter 5.3 --- Further Study --- p.64 / Chapter 5.4 --- Publications --- p.65 / Bibliography --- p.65
52

Entropy coding and post-processing for image and video coding.

January 2010 (has links)
Fong, Yiu Leung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 83-87). / Abstracts in English and Chinese. / Abstract --- p.2 / Acknowledgement --- p.6 / Chapter 1. --- Introduction --- p.9 / Chapter 2. --- Background and Motivation --- p.10 / Chapter 2.1 --- Context-Based Arithmetic Coding --- p.10 / Chapter 2.2 --- Video Post-processing --- p.13 / Chapter 3. --- Context-Based Arithmetic Coding for JPEG --- p.16 / Chapter 3.1 --- Introduction --- p.16 / Chapter 3.1.1 --- Huffman Coding --- p.16 / Chapter 3.1.1.1 --- Introduction --- p.16 / Chapter 3.1.1.2 --- Concept --- p.16 / Chapter 3.1.1.3 --- Drawbacks --- p.18 / Chapter 3.1.2 --- Context-Based Arithmetic Coding --- p.19 / Chapter 3.1.2.1 --- Introduction --- p.19 / Chapter 3.1.2.2 --- Concept --- p.20 / Chapter 3.2 --- Proposed Method --- p.30 / Chapter 3.2.1 --- Introduction --- p.30 / Chapter 3.2.2 --- Redundancy in Quantized DCT Coefficients --- p.32 / Chapter 3.2.2.1 --- Zig-Zag Scanning Position --- p.32 / Chapter 3.2.2.2 --- Magnitudes of Previously Coded Coefficients --- p.41 / Chapter 3.2.3 --- Proposed Scheme --- p.43 / Chapter 3.2.3.1 --- Overview --- p.43 / Chapter 3.2.3.2 --- Preparation of Coding --- p.44 / Chapter 3.2.3.3 --- Coding of Non-zero Coefficient Flags and EOB Decisions --- p.45 / Chapter 3.2.3.4 --- Coding of ´بLEVEL' --- p.48 / Chapter 3.2.3.5 --- Separate Coding of Color Planes --- p.53 / Chapter 3.3 --- Experimental Results --- p.54 / Chapter 3.3.1 --- Evaluation Method --- p.54 / Chapter 3.3.2 --- Methods under Evaluation --- p.55 / Chapter 3.3.3 --- Average File Size Reduction --- p.57 / Chapter 3.3.4 --- File Size Reduction on Individual Images --- p.59 / Chapter 3.3.5 --- Performance of Individual Techniques --- p.63 / Chapter 3.4 --- Discussions --- p.66 / Chapter 4. --- Video Post-processing for H.264 --- p.67 / Chapter 4.1 --- Introduction --- p.67 / Chapter 4.2 --- Proposed Method --- p.68 / Chapter 4.3 --- Experimental Results --- p.69 / Chapter 4.3.1 --- Deblocking on Compressed Frames --- p.69 / Chapter 4.3.2 --- Deblocking on Residue of Compressed Frames --- p.72 / Chapter 4.3.3 --- Performance Investigation --- p.74 / Chapter 4.3.4 --- Investigation Experiment 1 --- p.75 / Chapter 4.3.5 --- Investigation Experiment 2 --- p.77 / Chapter 4.3.6 --- Investigation Experiment 3 --- p.79 / Chapter 4.4 --- Discussions --- p.81 / Chapter 5. --- Conclusions --- p.82 / References --- p.83
53

Listless zerotree image and video coding / Wen-Kuo Lin.

Lin, Wen-Kuo January 2001 (has links)
Includes bibliographical references (leaves 199-214) / xxx, 214 leaves : ill. (some col.), plates (col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 2002
54

A high-performance, low power and memory-efficient VLD for MPEG applications

Zhang, Haowei 14 January 1997 (has links)
An extremely important area that has enabled or will enable many of the digital video services and applications such as VideoCD, DVD, DVC, HDTV, video conferencing, and DSS is digital video compression. The great success of digital video compression is mainly because of two factors. The state of the art in very large scale integrated circuit (VLSI) and a considerable body of knowledge accumulated over the last several decades in applying video compression algorithms such as discrete cosine transform (DCT), motion estimation (ME), motion compensation (MC) and entropy coding techniques. The MPEG (Moving Pictures Expert Group) standard reflects the second factor. In this thesis, MPEG standards are discussed thoroughly and interpreted, and a VLSI chip implementation (CMOS 0.35�� technology and 3 layer metal) of a variable length decoder (VLD) for MPEG applications is developed. The VLD developed here achieves high performance by using a parallel and pipeline architecture. Furthermore, MPEG bitstream patterns are carefully analyzed in order to drastically improve VLD memory efficiency. Finally, a special clock scheme is applied to reduce the chip's power consumption. / Graduation date: 1998
55

Improving motion estimation with evolvable search algorithms

Dill, Martin D. 09 June 1997 (has links)
Until now the topic of motion estimation, as used in video compression, has been dominated by search methodologies which are modifications of an exhaustive search. This research takes a completely new approach by applying two evolvable search algorithms, the Genetic Algorithm and the Genetic Program, to the area of motion estimation. The main purpose of this research is to determine the applicability of evolvable search methods to the topic of motion estimation. Several methods are studied: in the first application, a Genetic Algorithm is used to determine individual motion vectors one at a time, while the second method explores the use of a Genetic Algorithm to search for all of the motion vectors to correlate two frames simultaneously. To reduce the number of motion vectors required, Genetic Programming is applied to variable block size motion estimation. Finally, this work is expanded by applying it to region motion estimation, which is not restricted to using square or rectangular motion blocks. / Graduation date: 1998
56

Distributed arithmetic architecture for the discrete cosine transform

Poplin, Dwight 02 May 1997 (has links)
The Discrete Cosine Transform is used in many image and video compression standards. Many methods have been developed for efficiently computing the Discrete Cosine Transform including flowgraph algorithms, distributed arithmetic and two-dimensional decompositions. A new architecture based on distributed arithmetic is presented for computing the Discrete Cosine Transform and it's inverse. The main objective of the design is to minimize the area of the VLSI implementation while maintaining the throughput necessary for video and image compression standards such as MPEG and JPEG. Several improvements have been made compared to previously published distributed arithmetic architectures. These include elimination of four lookup tables and implementation of the lookup tables using logic instead of ROM. A model of the proposed architecture was written in C. The model was used to verify the accuracy of the architecture and to do JPEG compression on a series of test images. Behavioral simulations were performed with a hardware model written in the Verilog hardware description language. These behavioral simulations verify that the hardware implementation matches the C model. The model was synthesized using the Synopsis synthesis tool. The gate count and clock rate of the design were estimated using the synthesis results. / Graduation date: 1997
57

Joint source-channel distortion modeling for image and video communication

Sabir, Muhammad Farooq, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
58

CockTail Search (CTS) for Video Motion Estimation

Wei, Sheng-Li 29 June 2001 (has links)
The performance and speed of the interframe motion estimation method for sequencial frame sequence compression are the important issues especially in networking application such as video conference and video on demand. In this paper, we proposed a new fast search algorithm for motion estimation on block matching technique called the cocktail search algorithm (CTS). This new algorithm takes advantages of prior search algorithms proposed in the literature and improves at our observations. The experiment results show that the proposed CTS algorithm can provide the better performance and require less computational costs than others. In other words, the CTS can obtain the accurate motion vector efficiently and fast. The fruitful results is achieved by not only holding the original benefit but also constructively improving the existing drawbacks.
59

Modified Motion Estimating Methods for Increasing Video Compression Rate

Wang, Sheng-Hung 28 June 2002 (has links)
In recent years, the internet has been in widespread use and the number of internet subscribers increased quickly. Hence a lot of applications on the network have been developed, multimedia programs especially. Whereas the original video content always takes up considerable storage and transmission time which doesn¡¦t suit for network application, many video compression standards have been drawn up in the literature Due to the temporal redundancy of the video sequences, motion estimation / compensation has been widely used in many interframe video coding protocols to reduce the required bit rates for transmission and storage of video signals by eliminating it, such as the MPEG-1, MPEG-2, H.261 and H.263. The performance and speed of the interframe motion estimation method for video sequence compression are the important issues especially in networking application such as video conference and video on demand. Today all motion estimating method find out the estimating point which has minimal Mean Square Error, and motion compensation aim at estimating error to do JPEG. compression. As everyone knows, JPEG employs DCT to eliminate the correlation of spatial domain. So the best motion estimating point is the point which has the minimal compressed data size. In some alalyses show that over 50% best estimating point do not have the minimal compressed data size. So the factor which effects the compressed data size is correlation coefficient and not MSE. Hence, we try to define a new criterion for motion estimation which can get better motion compensation with less compressing bit rate. To reach this goal, we try to find out the correlation among the motion compensation as the new criterion for motion estimation.
60

Digital video segmentation and annotation in news programs

Wang, Yang, January 2001 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 130-133).

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