We propose a polarization-multiplexed iterative polar quantization (IPQ)-based LDPC-coded-modulation scheme suitable for beyond 400 Gb/s serial optical transmission. The component LDPC codes are designed using modifie...
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We propose a polarization-multiplexed iterative polar quantization (IPQ)-based LDPC-coded-modulation scheme suitable for beyond 400 Gb/s serial optical transmission. The component LDPC codes are designed using modified progressive edge-growth (MPEG) algorithm. The proposed scheme employs 32-IPQ-based-modulation.
In the article the matters of TV video streams compression efficiency increasing by codecs on the basis of wavelet transformations due to time redundancy elimination using different variants of forming the interframe ...
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ISBN:
(纸本)9781424422821
In the article the matters of TV video streams compression efficiency increasing by codecs on the basis of wavelet transformations due to time redundancy elimination using different variants of forming the interframe difference are considered. The experimental results of interframe difference compression of different items against to the key frames are presented.
Stream control transmission protocol (SCTP) is a transport layer protocol for the next-generation Internet. In this paper, we investigate optimally condition for MPEG 4 video communication with SCTP in 802.11 wireless...
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ISBN:
(纸本)9784885522260
Stream control transmission protocol (SCTP) is a transport layer protocol for the next-generation Internet. In this paper, we investigate optimally condition for MPEG 4 video communication with SCTP in 802.11 wireless access media. We focus on the multi-streaming feature and the partial reliability extension in SCTP and compare performance of MPEG4 video quality under the policy w th/without differentiated retransmission among streams. Differentiated policy allows packets belonging to a specific stream to be retransmitted, while packets are transmitted exactly one time (no retransmissions) in homogeneous policy. By computer simulation, we show that SCTP can (1) improve the video quality by exploiting the multi-streaming and partial reliability features, and (2) enhance the video transmission quality can by adjusting SCTP fast retransmit threshold.
We present a strategy based on local SNR for variable-rate encoding of a variety of telephony signals using Adaptive transform coding. We first describe simple modifications of the speech version of ATC, involving chi...
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We present a strategy based on local SNR for variable-rate encoding of a variety of telephony signals using Adaptive transform coding. We first describe simple modifications of the speech version of ATC, involving chiefly the side information quantization and the bit allocation procedures, which substantially improve fixed-rate encoding performance on modem signals. Then, using simple statistical models of bit-rate demand, we predict the compression performance of the variable-rate encoder in a typical telephony network. We compare the performance of variable-rate and fixed-rate encoding of speech and modem signals, based on extensive listening tests and simulations, respectively. We also report on the progress of an experimental implementation of the algorithm in 32-bit floating-point hardware.
In this paper, a novel human activity recognition method is presented. The proposed solution uses a single stationary camera in order to detect common human activities like: hand waving, walking, running etc. Unlike o...
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In this paper, a novel human activity recognition method is presented. The proposed solution uses a single stationary camera in order to detect common human activities like: hand waving, walking, running etc. Unlike other methods which use different kinds of characteristic point descriptors in order to describe human poses, the proposed solution uses a CDVS descriptor which is part of the MPEG-7 standard. This allows the efficient calculation of a compact descriptor in a camera. The main goal of this work is to propose an efficient application of CDVS to describe and recognize different human activities. The experiments were performed on the Weizmann and KTH datasets. The obtained results prove the high accuracy of human activity recognition system with CDVS.
This paper discusses a new method of using neural networks for super-high, scale invariant image compression. This is achieved by training an multilayer perceptron (MLP) network to learn an approximation to a two-dime...
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This paper discusses a new method of using neural networks for super-high, scale invariant image compression. This is achieved by training an multilayer perceptron (MLP) network to learn an approximation to a two-dimensional image surface. One of the main features of this network is its ability to perform unsupervised feature extraction and in so doing represent image features in a compact form the results demonstrate the potential for significantly superior edge reproduction at super-high compression as compared to standard subband coding methods.< >
A computationally efficient camera motion estimation algorithm based on feature points derived from compressed domain is presented. The feature point selection algorithm employs the texture/edge information contained ...
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A computationally efficient camera motion estimation algorithm based on feature points derived from compressed domain is presented. The feature point selection algorithm employs the texture/edge information contained in the DCT (discrete cosine transform) coefficients and is therefore directly applicable to DCT-based compressed video (like MPEG-1/-2/-4, H.261, H.263, DV or the MJPEG format). This paper describes: (1) the extraction of the feature-points in the compressed domain, (2) the application of computationally efficient motion estimation on these feature points by taking advantage of existing motion vectors in the MPEG compressed domain, as well as (3) an application for camera motion estimation.
The architecture for the transform domain transcoder from MPEG-2 Video to MPEG-4 AVC is presented in the paper. The possible solutions for main components of the transcoder are analysed. The modification of the algori...
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The architecture for the transform domain transcoder from MPEG-2 Video to MPEG-4 AVC is presented in the paper. The possible solutions for main components of the transcoder are analysed. The modification of the algorithm for compensation of the drift caused by the different half-pixel samples interpolation methods used in MPEG-2 Video and MPEG-4 AVC/H.264 is also proposed.
A recently introduced algebraic integer encoding scheme allows low complexity, virtually error free computation of the DCT and IDCT. Efficiencies can be introduced into this method, but at the expense of some increase...
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ISBN:
(纸本)0780366859
A recently introduced algebraic integer encoding scheme allows low complexity, virtually error free computation of the DCT and IDCT. Efficiencies can be introduced into this method, but at the expense of some increase in error. In this paper, a modification to the encoding scheme is introduced for specific architectures which provides increased implementation efficiency, but with no sacrifice in accuracy. We provide a theoretical study of this new approach and illustrate the technique using selected DCT and IDCT algorithms.
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