In this paper, we propose an efficient and embedded3-d wavelet video coding algorithm, which exploits inter- and intra-subband correlations along spatial and temporal directions through the use of spatio-temporal ori...
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ISBN:
(纸本)9781424424085
In this paper, we propose an efficient and embedded3-d wavelet video coding algorithm, which exploits inter- and intra-subband correlations along spatial and temporal directions through the use of spatio-temporal orientation trees. The spatio-temporal tree structure has nodes as a block of n x n coefficients as a basic unit in contrast to a single coefficient in the 3-d SPIHT. The proposed algorithm combines the benefits of both 3-d zerotree and zeroblock basedcoding approaches in a single algorithm. This not only helps in exploitation of both inter- and intra-subband correlations efficiently but also results in better aggregation of zerotrees. Simulation results show the improved performance of the proposed coder over a 3-d SPIHT coder for the test sequences considered. Like 3-d SPIHT, the proposed algorithm posses all its functionatities such as fully embedded bit stream, precise rate control and multi-resolution scalability.
We propose an embedded3-dwavelet basedvideocoding technique with reduced complexity. The key idea is the use of a composite block-tree hierarchical structure to link blocks of wavelet coefficients in spatial, temp...
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ISBN:
(纸本)9781424427505
We propose an embedded3-dwavelet basedvideocoding technique with reduced complexity. The key idea is the use of a composite block-tree hierarchical structure to link blocks of wavelet coefficients in spatial, temporal and color planes in such a way that a large number of the insignificant sets are coded together. The proposed technique integrates the set partitioning strategies of hierarchical trees and blocks into a single algorithm, resulting in improvement in the coding efficiency and reduction in the computational complexity. Simulation results show the performance improvement in coding efficiency and up to 50% reduction in the computational complexity over the 3-d SPIHT video coder.
The motion compensated temporal filtering (MCTF) technique, which is extensively used in 3-d) waveletvideocoding schemes nowadays, leads to signal coupling among various spatial subbands because motion alignment is ...
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The motion compensated temporal filtering (MCTF) technique, which is extensively used in 3-d) waveletvideocoding schemes nowadays, leads to signal coupling among various spatial subbands because motion alignment is introduced in the temporal filtering. Using all spatial subbands as a reference enables MCTF to fully take advantage of temporal correlation across frames but inevitably brings drifting problem in supporting spatial scalability. This paper first analyzes the signal coupling phenomenon and then proposes a quantitative model to describe signal propagation across spatial subbands during the MCTF process. The signal propagation is modeled for a single MC step based on the shifting effect of wavelet synthesis filters and then it is extended to multilevel MCTF. This model is called subband coupling aware signal propagation (SCASP) model in this paper. Based on the model, we further propose a subband coupling aware rate allocation scheme as one possible solution to the above dilemma in supporting spatial scalability. To find the optimal rate allocation among all subbands for a specified reconstruction resolution, the SCASP model is used to approximate the reconstruction process andderive the synthesis gain of each subband with regard to that reconstruction. Experimental results have fully demonstrated the advantages of our proposed rate allocation scheme in improving both objective and subjective qualities of reconstructed low-resolution video, especially at middle bit rates and high bit rates.
This paper provides an overview of the Barbell lifting coding scheme that has been adopted as common software by the MPEG ad hoc group on further exploration of waveletvideocoding. The core techniques used in this s...
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This paper provides an overview of the Barbell lifting coding scheme that has been adopted as common software by the MPEG ad hoc group on further exploration of waveletvideocoding. The core techniques used in this scheme, such as Barbell lifting, layered motion coding, 3-d entropy coding and base layer embedding, are discussed. The paper also analyzes and compares the proposed scheme with the oncoming Scalable videocoding (SVC) standard because the hierarchical temporal prediction technique used in SVC has a close relationship with motion compensated temporal lifting (MCTF) in waveletcoding. The commonalities anddifferences between these two schemes are exhibited for readers to better understand modern scalable videocoding technologies. Several challenges that still exist in scalable videocoding, e.g., performance of spatial scalable coding and accurate MC lifting, are also discussed. Two new techniques are presented in this paper although they are not yet integrated into the common software. Finally, experimental results demonstrate the performance of the Barbell-lifting coding scheme and compare it with SVC and another well-known 3-dwaveletcoding scheme, MC embedded zero block coding (MC-EZBC).
Three-dimensional (3-d) wavelet-based scalable videocoding provides a viable alternative to standard MC-dCT coding. However, many current 3-dwavelet coders experience severe boundary effects across group of pictures...
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Three-dimensional (3-d) wavelet-based scalable videocoding provides a viable alternative to standard MC-dCT coding. However, many current 3-dwavelet coders experience severe boundary effects across group of pictures (GOP) boundaries. This paper proposes a memory-efficient transform technique via lifting that effectively computes wavelet transforms of a video sequence continuously on the fly, thus eliminating the boundary effects due to limited length of individual GOPs. coding results show that the proposed scheme completely eliminates the boundary effects and gives superb video playback quality.
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