Most of the Wyner-Ziv (WZ) video coding schemes in literature model the correlationnoise (CN) between original frame and side information (SI) by a given distribution whose parameters are estimated in an offline proc...
详细信息
ISBN:
(纸本)9781424456536
Most of the Wyner-Ziv (WZ) video coding schemes in literature model the correlationnoise (CN) between original frame and side information (SI) by a given distribution whose parameters are estimated in an offline process. In this paper, an online CN modeling algorithm is proposed towards a more practical WZ-based error resilient video coding (WZ-ERVC). In ERVC scenario, the side-information is typically generated from the error concealed picture instead of bi-directional motion prediction. The proposed online CN modeling algorithm achieves the so-called classification gain by exploiting the spatially non-stationary characteristics of the motion field and texture. The CN between the source and error concealed SI is modeled by a Laplacian mixture model, where each mixture component represents the statistical distribution of prediction residuals and the mixing coefficients portray the motion vectors estimation error. Experimental results demonstrate significant performance gains both in rate and distortion versus the conventional Laplacian model.
Distributed video coding (DVC) is a paradigm that can shift most of the computational intensive tasks from the encoder to the decoder. This allows for the design of low complexity encoders that can be deployed in devi...
详细信息
Distributed video coding (DVC) is a paradigm that can shift most of the computational intensive tasks from the encoder to the decoder. This allows for the design of low complexity encoders that can be deployed in devices equipped with limited resources. However, the compression efficiency obtained using practical DVC codecs are still distant from those of traditional predictive video coding schemes such as H.264/AVC. One of the limitations of the existing DVC architectures is that they consider the correlationnoise to be randomly distributed across the whole video frame. This paper shows that the Wyner-Ziv (WZ) values that are closer to the endpoints of the quantization intervals have a higher probability of producing incorrect side information (SI) predictions. Thus, through this knowledge, rateadaptive low-density parity-check accumulate codes that provide a higher level of protection to the unreliable SI bits can be exploited. Experimental results show that the proposed scheme can reduce the WZ bit-rate up to 13% relative to the state-ofthe- art DISCOVER architecture when considering interpolation techniques and by up to 0.9 dB for extrapolation techniques.
correlation noise modeling (CNM) is a key factor to influence the performance of Distributed Video Coding (DVC). In most current CNM solutions, the distribution parameter is estimated based on the motion compensated r...
详细信息
ISBN:
(纸本)9781457713033
correlation noise modeling (CNM) is a key factor to influence the performance of Distributed Video Coding (DVC). In most current CNM solutions, the distribution parameter is estimated based on the motion compensated residual frames and kept constant during the decoding process. A progressive correlationnoise refinement method is proposed in this paper for transform domain Wyner-Ziv video coding to model the correlationnoise more accurately, in which the estimated correlationnoise is refined by using previously decoded bitplanes and quantization errors as bitplane decoding proceeds. The experimental results show that our proposed correlationnoise refinement method could provide considerable bitrate savings and PSNR gains for transform domain Wyner-Ziv video coding system.
Distributed video coding (DVC) is a new video coding paradigm based upon two fundamental theoretical results: the Slepian-Wolf and Wyner-Ziv theorems. Among other benefits, this new coding paradigm may allow a flexibl...
详细信息
Distributed video coding (DVC) is a new video coding paradigm based upon two fundamental theoretical results: the Slepian-Wolf and Wyner-Ziv theorems. Among other benefits, this new coding paradigm may allow a flexible complexity allocation between the encoder and the decoder. Several DVC codecs have been developed over the years addressing the specific requirements of emerging applications such as wireless video surveillance and sensor networks. While state-of-the-art DVC codecs, such as the DISCOVER DVC codec, have shown promising RD performance, most DVC codecs in the literature do not consider low delay requirements which are relevant for some of the addressed applications. In this context, the main objective and novelty of this paper is to propose an efficient, low delay and fully practical DVC codec based on the Stanford DVC architecture adopting a side information iterative refinement approach. The obtained performance results show that the developed DVC solution fulfils the objectives regarding relevant benchmarks, notably due to the novel side information creation and correlation noise modeling tools integrated in a side information iterative refinement framework (C) 2011 Elsevier B.V. All rights reserved.
In this paper, we propose a generic error resilient video coding (ERVC) scheme using embedded Wyner-Ziv (WZ) description. At the encoder side, a joint source-channel R-D optimized mode selection (JSC-RDO-MS) algorithm...
详细信息
In this paper, we propose a generic error resilient video coding (ERVC) scheme using embedded Wyner-Ziv (WZ) description. At the encoder side, a joint source-channel R-D optimized mode selection (JSC-RDO-MS) algorithm with WZ-coded anchor frames is statistically studied and developed. Given a stationary first-order Markov Gaussian source, the proposed mode optimization is justified by an analysis of the RD impact on the WZ bit-rate. JSC-RDO-MS involves in the estimation of expected rate and distortion of WZ coding with the unavailable side information, and the WZ bit-rate of each coding mode is determined based on the error correction capability of the specific WZ codec. At the decoder side, an online correlationnoise model between the source and the side-information is proposed with a mixture of Laplacians whose parameters are attained to reflect the coherence of the motion field of successive frames and the energy of prediction residual. Each mixture component represents the statistical distribution of prediction residuals, and the mixing coefficients represent the amount of errors in motion compensation. The proposed scheme achieves the so-called classification gain by exploiting the spatially non-stationary characteristics of the motion field and texture. Extensive experimental results show that the proposed WZ-ERVC scheme achieves a better overall RD performance than existing ERVC schemes, and the proposed modeling algorithm also significantly outperforms the conventional Laplacian model by up to 2 dB.
Among the emerging video coding schemes, the effectual solution for the separate-encoding and joint-decoding architecture is the distributed source coding (DSC). In the DSC-based video system, the side information is ...
详细信息
ISBN:
(纸本)9781467302197
Among the emerging video coding schemes, the effectual solution for the separate-encoding and joint-decoding architecture is the distributed source coding (DSC). In the DSC-based video system, the side information is available in the Wyner-Ziv (WZ) decoder and video reconstruction. Theoretically, the quality of side information (SI), usually referring to the difference between SI and source, dominates the coding efficiency. In order to improve the coding efficiency of DVC with temporal group of blocks, we proposed three SI generations after analyzing the correlation between the SI and original information. In contrast to the traditional improvement in the DVC decoder, the complexity of SI generator was dramatically reduced in our schemes. Experimental results show that the best method can reduce 0.7% bit-rate with less computation and no codec delay compared to the bi-linear interpolation (BLI) method.
暂无评论