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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.
1

Motion-adaptive transforms for highly scalable video compression

Secker, Andrew J, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW January 2004 (has links)
This thesis investigates motion-adaptive temporal transformations and motion parameter coding schemes, for highly scalable video compression. The first aspect of this work proposes a new framework for constructing temporal discrete wavelet transforms, based on motion-compensated lifting steps. The use of lifting preserves invertibility regardless of the selected motion model. By contrast, the invertibility requirement has restricted previous approaches to either block-based or global motion compensation. We show that the proposed framework effectively applies the temporal wavelet transform along the motion trajectories. Video sequences reconstructed at reduced frame-rates, from subsets of the compressed bitstream, demonstrate the visually pleasing properties expected from lowpass filtering along the motion trajectories. Experimental results demonstrate the effectiveness of temporal wavelet kernels other than the simple Haar. We also demonstrate the benefits of complex motion modelling, by using a deformable triangular mesh. These advances are either incompatible or diffcult to achieve with previously proposed strategies for scalable video compression. A second aspect of this work involves new methods for the representation, compression and rate allocation of the motion information. We first describe a compact representation for the various motion mappings associated with the proposed lifting transform. This representation significantly reduces the number of distinct motion fields that must be transmitted to the decoder. We also incorporate a rate scalable scheme for coding the motion parameters. This is achieved by constructing a set of quality layers for the motion information, in a manner similar to that used to construct the scalable sample representation. When the motion layers are truncated, the decoder receives a quantized version of the motion parameters used to code the sample data. A linear model is employed to quantify the effects of motion parameter quantization on the reconstructed video distortion. This allows the optimal trade-off between motion and subband sample bit-rates to be determined after the motion and sample data has been compressed. Two schemes are proposed to determine the optimal trade-off between motion and sample bit-rates. The first scheme employs a simple but effective brute force search approach. A second scheme explicitly utilizes the linear model, and yields comparable performance to the brute force scheme, with significantly less computational cost. The high performance of the second scheme also serves to reinforce the validity of the linear model itself. In comparison to existing scalable coding schemes, the proposed video coder achieves significantly higher compression performance, and motion scalability facilitates effcient compression even at low bit-rates. Experimental results show that the proposed scheme is also competitive with state-of-the-art non-scalable video coders.
2

Adaptive techniques for scalable video compression /

Mehrseresht, Nagita. January 2005 (has links)
Thesis (Ph. D.)--University of New South Wales, 2005. / Also available online.
3

Vector subband video coding /

Wus, John Peter, January 1997 (has links)
Thesis (Ph. D.)--Lehigh University, 1997. / Includes vita. Includes bibliographical references (leaves 183-191).
4

Real time video compression using DVQ and suffix trees

Vedantam, Pavan Kumar. January 2004 (has links)
Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains vii, 57 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 55-57).
5

A novel bit allocation buffer control algorithm for low bit-rate video compression /

Ng, King-to. January 1998 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 133-136).
6

Focal plane video compression

León-Salas, Walter D. January 1900 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed May 22, 2007). PDF text: ix, 175 p. : ill. (some col.) ; 1.39Mb. UMI publication number: AAT 3237056. Includes bibliographical references. Also available in microfilm and microfiche formats.
7

Joint image/video inpainting for error concealment in video coding

Chen, Liyong, 陳黎勇 January 2007 (has links)
published_or_final_version / abstract / Electrical and Electronic Engineering / Master / Master of Philosophy
8

Performance and computational complexity optimization techniques in configurable video coding system

Kwon, Nyeongkyu. 10 April 2008 (has links)
No description available.
9

Variable block size motion estimation hardware for video encoders.

January 2007 (has links)
Li, Man Ho. / Thesis submitted in: November 2006. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 137-143). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iv / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivation --- p.3 / Chapter 1.2 --- The objectives of this thesis --- p.4 / Chapter 1.3 --- Contributions --- p.5 / Chapter 1.4 --- Thesis structure --- p.6 / Chapter 2 --- Digital video compression --- p.8 / Chapter 2.1 --- Introduction --- p.8 / Chapter 2.2 --- Fundamentals of lossy video compression --- p.9 / Chapter 2.2.1 --- Video compression and human visual systems --- p.10 / Chapter 2.2.2 --- Representation of color --- p.10 / Chapter 2.2.3 --- Sampling methods - frames and fields --- p.11 / Chapter 2.2.4 --- Compression methods --- p.11 / Chapter 2.2.5 --- Motion estimation --- p.12 / Chapter 2.2.6 --- Motion compensation --- p.13 / Chapter 2.2.7 --- Transform --- p.13 / Chapter 2.2.8 --- Quantization --- p.14 / Chapter 2.2.9 --- Entropy Encoding --- p.14 / Chapter 2.2.10 --- Intra-prediction unit --- p.14 / Chapter 2.2.11 --- Deblocking filter --- p.15 / Chapter 2.2.12 --- Complexity analysis of on different com- pression stages --- p.16 / Chapter 2.3 --- Motion estimation process --- p.16 / Chapter 2.3.1 --- Block-based matching method --- p.16 / Chapter 2.3.2 --- Motion estimation procedure --- p.18 / Chapter 2.3.3 --- Matching Criteria --- p.19 / Chapter 2.3.4 --- Motion vectors --- p.21 / Chapter 2.3.5 --- Quality judgment --- p.22 / Chapter 2.4 --- Block-based matching algorithms for motion estimation --- p.23 / Chapter 2.4.1 --- Full search (FS) --- p.23 / Chapter 2.4.2 --- Three-step search (TSS) --- p.24 / Chapter 2.4.3 --- Two-dimensional Logarithmic Search Algorithm (2D-log search) --- p.25 / Chapter 2.4.4 --- Diamond Search (DS) --- p.25 / Chapter 2.4.5 --- Fast full search (FFS) --- p.26 / Chapter 2.5 --- Complexity analysis of motion estimation --- p.27 / Chapter 2.5.1 --- Different searching algorithms --- p.28 / Chapter 2.5.2 --- Fixed-block size motion estimation --- p.28 / Chapter 2.5.3 --- Variable block size motion estimation --- p.29 / Chapter 2.5.4 --- Sub-pixel motion estimation --- p.30 / Chapter 2.5.5 --- Multi-reference frame motion estimation . --- p.30 / Chapter 2.6 --- Picture quality analysis --- p.31 / Chapter 2.7 --- Summary --- p.32 / Chapter 3 --- Arithmetic for video encoding --- p.33 / Chapter 3.1 --- Introduction --- p.33 / Chapter 3.2 --- Number systems --- p.34 / Chapter 3.2.1 --- Non-redundant Number System --- p.34 / Chapter 3.2.2 --- Redundant number system --- p.36 / Chapter 3.3 --- Addition/subtraction algorithm --- p.38 / Chapter 3.3.1 --- Non-redundant number addition --- p.39 / Chapter 3.3.2 --- Carry-save number addition --- p.39 / Chapter 3.3.3 --- Signed-digit number addition --- p.40 / Chapter 3.4 --- Bit-serial algorithms --- p.42 / Chapter 3.4.1 --- Least-significant-bit (LSB) first mode --- p.42 / Chapter 3.4.2 --- Most-significant-bit (MSB) first mode --- p.43 / Chapter 3.5 --- Absolute difference algorithm --- p.44 / Chapter 3.5.1 --- Non-redundant algorithm for absolute difference --- p.44 / Chapter 3.5.2 --- Redundant algorithm for absolute difference --- p.45 / Chapter 3.6 --- Multi-operand addition algorithm --- p.47 / Chapter 3.6.1 --- Bit-parallel non-redundant adder tree implementation --- p.47 / Chapter 3.6.2 --- Bit-parallel carry-save adder tree implementation --- p.49 / Chapter 3.6.3 --- Bit serial signed digit adder tree implementation --- p.49 / Chapter 3.7 --- Comparison algorithms --- p.50 / Chapter 3.7.1 --- Non-redundant comparison algorithm --- p.51 / Chapter 3.7.2 --- Signed-digit comparison algorithm --- p.52 / Chapter 3.8 --- Summary --- p.53 / Chapter 4 --- VLSI architectures for video encoding --- p.54 / Chapter 4.1 --- Introduction --- p.54 / Chapter 4.2 --- Implementation platform - (FPGA) --- p.55 / Chapter 4.2.1 --- Basic FPGA architecture --- p.55 / Chapter 4.2.2 --- DSP blocks in FPGA device --- p.56 / Chapter 4.2.3 --- Advantages employing FPGA --- p.57 / Chapter 4.2.4 --- Commercial FPGA Device --- p.58 / Chapter 4.3 --- Top level architecture of motion estimation processor --- p.59 / Chapter 4.4 --- Bit-parallel architectures for motion estimation --- p.60 / Chapter 4.4.1 --- Systolic arrays --- p.60 / Chapter 4.4.2 --- Mapping of a motion estimation algorithm onto systolic array --- p.61 / Chapter 4.4.3 --- 1-D systolic array architecture (LA-ID) --- p.63 / Chapter 4.4.4 --- 2-D systolic array architecture (LA-2D) --- p.64 / Chapter 4.4.5 --- 1-D Tree architecture (GA-1D) --- p.64 / Chapter 4.4.6 --- 2-D Tree architecture (GA-2D) --- p.65 / Chapter 4.4.7 --- Variable block size support in bit-parallel architectures --- p.66 / Chapter 4.5 --- Bit-serial motion estimation architecture --- p.68 / Chapter 4.5.1 --- Data Processing Direction --- p.68 / Chapter 4.5.2 --- Algorithm mapping and dataflow design . --- p.68 / Chapter 4.5.3 --- Early termination scheme --- p.69 / Chapter 4.5.4 --- Top-level architecture --- p.70 / Chapter 4.5.5 --- Non redundant positive number to signed digit conversion --- p.71 / Chapter 4.5.6 --- Signed-digit adder tree --- p.73 / Chapter 4.5.7 --- SAD merger --- p.74 / Chapter 4.5.8 --- Signed-digit comparator --- p.75 / Chapter 4.5.9 --- Early termination controller --- p.76 / Chapter 4.5.10 --- Data scheduling and timeline --- p.80 / Chapter 4.6 --- Decision metric in different architectural types . . --- p.80 / Chapter 4.6.1 --- Throughput --- p.81 / Chapter 4.6.2 --- Memory bandwidth --- p.83 / Chapter 4.6.3 --- Silicon area occupied and power consump- tion --- p.83 / Chapter 4.7 --- Architecture selection for different applications . . --- p.84 / Chapter 4.7.1 --- CIF and QCIF resolution --- p.84 / Chapter 4.7.2 --- SDTV resolution --- p.85 / Chapter 4.7.3 --- HDTV resolution --- p.85 / Chapter 4.8 --- Summary --- p.86 / Chapter 5 --- Results and comparison --- p.87 / Chapter 5.1 --- Introduction --- p.87 / Chapter 5.2 --- Implementation details --- p.87 / Chapter 5.2.1 --- Bit-parallel 1-D systolic array --- p.88 / Chapter 5.2.2 --- Bit-parallel 2-D systolic array --- p.89 / Chapter 5.2.3 --- Bit-parallel Tree architecture --- p.90 / Chapter 5.2.4 --- MSB-first bit-serial design --- p.91 / Chapter 5.3 --- Comparison between motion estimation architectures --- p.93 / Chapter 5.3.1 --- Throughput and latency --- p.93 / Chapter 5.3.2 --- Occupied resources --- p.94 / Chapter 5.3.3 --- Memory bandwidth --- p.95 / Chapter 5.3.4 --- Motion estimation algorithm --- p.95 / Chapter 5.3.5 --- Power consumption --- p.97 / Chapter 5.4 --- Comparison to ASIC and FPGA architectures in past literature --- p.99 / Chapter 5.5 --- Summary --- p.101 / Chapter 6 --- Conclusion --- p.102 / Chapter 6.1 --- Summary --- p.102 / Chapter 6.1.1 --- Algorithmic optimizations --- p.102 / Chapter 6.1.2 --- Architecture and arithmetic optimizations --- p.103 / Chapter 6.1.3 --- Implementation on a FPGA platform . . . --- p.104 / Chapter 6.2 --- Future work --- p.106 / Chapter A --- VHDL Sources --- p.108 / Chapter A.1 --- Online Full Adder --- p.108 / Chapter A.2 --- Online Signed Digit Full Adder --- p.109 / Chapter A.3 --- Online Pull Adder Tree --- p.110 / Chapter A.4 --- SAD merger --- p.112 / Chapter A.5 --- Signed digit adder tree stage (top) --- p.116 / Chapter A.6 --- Absolute element --- p.118 / Chapter A.7 --- Absolute stage (top) --- p.119 / Chapter A.8 --- Online comparator element --- p.120 / Chapter A.9 --- Comparator stage (top) --- p.122 / Chapter A.10 --- MSB-first motion estimation processor --- p.134 / Bibliography --- p.137
10

Hybrid transform, spatial decorrelation and unified coding system for image and video compression /

Lee, Kenneth Ka Chun. January 2004 (has links) (PDF)
Thesis (Ph.D.)--City University of Hong Kong, 2004. / "Submitted to Department of Computer Science in partial fulfillment of the requirements for the degree of Doctor of Philosophy" Includes bibliographical references (leaves 145-158)

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