We propose a content aware scheduler to allocate resources for video delivery on the downlink of a Long Term Evolution (LTE) network. We consider multiple users subscribe to a video streaming service, and request vide...
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ISBN:
(纸本)9783642452482;9783642452499
We propose a content aware scheduler to allocate resources for video delivery on the downlink of a Long Term Evolution (LTE) network. We consider multiple users subscribe to a video streaming service, and request videos encoded in H.264 scalable video coding format. The scheduler maximizes the average video quality across all users by assigning resource blocks based on their device capabilities, link qualities, and available resources. We measure video quality using two full reference metrics: peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) index. We formulate the video delivery problem first as an integer linear program (ILP), and then reduce it to the multiple choice knapsack problem (MCKP). To solve the MCKP, we propose two fast heuristics with reduced processing overhead at the eNodeB, and a fully polynomial-time approximate scheme (FPTAS) using dynamic programming and profit-scaling. Our evaluation results indicate that the heuristics are within a factor of 1/2, and the FPTAS is very close to the optimal obtained from an ILP solver. We also propose a signaling mechanism to implement the content aware scheduler in existing LTE systems, and evaluate the impact of signaling delay on video distortion using both indoor and outdoor measurements collected from AT&T and T-Mobile networks.
In this paper, we present a temporal candidate generation scheme that can be applied to motion estimators in scalablevideo Codecs (SVCs). For bidirectional motion estimation, usually a test is made for each block to ...
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ISBN:
(纸本)9781424479948
In this paper, we present a temporal candidate generation scheme that can be applied to motion estimators in scalablevideo Codecs (SVCs). For bidirectional motion estimation, usually a test is made for each block to determine which motion compensation direction is preferred: forward, bidirectional or backward. Instead of simply using the last computed motion vector field (backward or forward), giving an asymmetry in the estimation, we involve both vector fields to generate a single candidate field for a more stable and improved prediction. This field is generated with the aid of mode decision information of the codec. This single field of motion vector candidates serves two purposes: (1) it initializes the next recursion and (2) it is the foundation for the succeeding scale in the scalablecoding. We have implemented this improved candidate system for both HPPS as EPZS motion estimators in a scalablevideo codec. We have found that it reduces the errors caused by occlusion of moving objects or image boundaries. For EPZS, only a small improvement is observed compared to the simple candidate scheme. However, for HPPS improvements are more significant: when looking at individual levels, motion compensation performance improves by up to 0.84 dB and when implemented in SVC, HPPS slightly outperforms EPZS.
In existing videocoding schemes with spatial scalability based on pyramid frame representation, such as the ongoing H.264/MPEG-4 SVC (scalable video coding) standard, video frame at a high resolution is mainly predic...
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ISBN:
(纸本)9780819466211
In existing videocoding schemes with spatial scalability based on pyramid frame representation, such as the ongoing H.264/MPEG-4 SVC (scalable video coding) standard, video frame at a high resolution is mainly predicted either from the lower-resolution image of the same frame or from the temporal neighboring frames at the same resolution. Most of these prediction techniques fail to exploit the two correlations simultaneously and efficiently. This paper extends the in-scale prediction technique developed for wavelet videocoding to a generalized in-scale motion compensation framework for H.264/MPEC-4 SVC. In this framework, for a video frame at a high resolution layer, the lowpass content is predicted from the information already coded in lower resolution layer, but the highpass content is predicted by exploiting the neighboring frames at current resolution. In this way, both the cross-resolution correlation and temporal correlation are exploited simultaneously, which leads to much higher efficiency in prediction. Preliminary experimental results demonstrate that the proposed framework improves the spatial scalability performance of current H.264/MPEG-4 SVC. The improvement is significant especially for high-fidelity videocoding. In addition, another advantage over wavelet-based in-scale scheme is achieved that the proposed framework can support arbitrary down-sampling and up-sampling filters.
scalable video coding (SVC) is an extension to H.264/AVC that enables encoding a video sequence once and using it subsequently at multiple operations points by different devices and applications. Forward Error Correct...
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ISBN:
(纸本)9781424446728
scalable video coding (SVC) is an extension to H.264/AVC that enables encoding a video sequence once and using it subsequently at multiple operations points by different devices and applications. Forward Error Correction techniques may then be applied to the encoded video in order to enhance the robustness against transmission errors. Media aware FEC code construction caters for scalablevideo streams by adjusting the protection level for each video layer. In this paper, we discuss different approaches for media aware Forward Error Correction using scalablevideo Coded video that is transmitted over error prone channels. We describe two recent solutions for Unequal Error Protection and then evaluate those through multiple simulations.
In this paper a thorough analysis on the theoretical rate distortion model and the rate distortion performance in an open-loop structure is conducted. A Lagrange multiplier selection for 3-D wavelet based scalable vid...
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ISBN:
(纸本)9781424414369
In this paper a thorough analysis on the theoretical rate distortion model and the rate distortion performance in an open-loop structure is conducted. A Lagrange multiplier selection for 3-D wavelet based scalable video coding is then derived. The proposed Lagrange multiplier is adaptive with respect to the characteristics of video content. Furthermore, it is especially suitable for 3-D wavelet based scalable video coding where quantisation steps are unavailable. Extensive experimental results have demonstrated the effectiveness of the proposed Lagrange multiplier selection.
In this paper we present an interoperable multimedia delivery framework for scalable video coding based on MPEG-21 Digital Item Adaptation (DIA). In can be used to transmit scalablevideo contents within heterogeneous...
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ISBN:
(纸本)9781424425709
In this paper we present an interoperable multimedia delivery framework for scalable video coding based on MPEG-21 Digital Item Adaptation (DIA). In can be used to transmit scalablevideo contents within heterogeneous usage environments where the properties of the usage environment (e.g., terminal/network capabilities) may change dynamically during the streaming session. The usage environment is signaled by interoperable description formats provided by the DIA standard. Additionally, the adaptation itself is done by exploiting the standard's generic adaptation approach, i.e., independent of the actual coding format. Thus, the overall framework is also applicable for other scalablecoding formats.
scalable video coding is a promising solution for efficient video content distribution to users having heterogeneous network and terminal capabilities. Thanks to its inherent multidimensional adaptability, a scalable ...
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ISBN:
(纸本)9781457713354
scalable video coding is a promising solution for efficient video content distribution to users having heterogeneous network and terminal capabilities. Thanks to its inherent multidimensional adaptability, a scalable bit stream can be used to simultaneously transmit multiple video sequences having different bit rates to corresponding target users, without necessity of re-encoding or transcoding. In order to exploit such an advantage effectively, it is crucial to understand the effects of multidimensional scalability options on the perceived quality and the trade-off between the scalability dimensions through subjective quality assessment. This paper reviews existing studies aiming at achieving this goal in order to summarize their results and common findings.
Transmitting the digital audio/visual data over the internet becomes more and more popular lately. Due to the heterogeneous networks and different hardware devices, the users have different requirements for the same m...
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Transmitting the digital audio/visual data over the internet becomes more and more popular lately. Due to the heterogeneous networks and different hardware devices, the users have different requirements for the same multimedia request. Thus, scalable video coding (SVC) was proposed and became an extension of H.264/AVC videocoding standard. To make the bitstream embedded while ensuring good coding efficiency, SVC uses inter-layer prediction to remove the redundancy between the enhancement layer and the base layer, in addition to intra prediction and inter prediction. After analyzing the coding efficiency brought by each kind of inter-layer prediction, the importance of inter-layer intra prediction is recognized. In this paper, we propose a new inter-layer infra prediction to improve the coding efficiency for spatial scalability. Experimental results show that an average 4.92% bitrate reduction is achieved by the proposed inter-layer infra prediction.
In this paper, a new framework is proposed for the encoder optimization of scalable video coding (SVC). It is used to provide guidelines for the design of rate control and fast mode decision at the base layer and base...
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ISBN:
(纸本)9781424412211
In this paper, a new framework is proposed for the encoder optimization of scalable video coding (SVC). It is used to provide guidelines for the design of rate control and fast mode decision at the base layer and base layer selection at enhancement layer for the SVC. It is also pointed out that the coding technology of inter-layer prediction with two base layers is desired for the combined coarse granular scalability and spatial scalability such that the coding efficiency losses at layers with higher resolution are about 10% when compared to the corresponding single-layer videocoding.
This paper presents a novel 3-D direction aligned wavelet transform for scalable video coding. A new generalized 3-D directional threading technique is seamlessly incorporated into 3-D weighted adaptive lifting (WAL)-...
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ISBN:
(纸本)9781424420780
This paper presents a novel 3-D direction aligned wavelet transform for scalable video coding. A new generalized 3-D directional threading technique is seamlessly incorporated into 3-D weighted adaptive lifting (WAL)-based wavelet transform to exploit the spatio-temporal correlation inside the video cube along the 3-D directional trajectory, leading to a new class of algorithm called 3-D direction aligned wavelet transform (DAWT). Experimental results show that the proposed 3-D WAL-based DAWT achieves better coding performance than the conventional 3-D discrete wavelet transform (3-D DWT).
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