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61.
Aykut Avci Jan De CockPeter Lambert Roel BeernaertJelle De Smet Lawrence BogaertYouri Meuret Hugo ThienpontHerbert De Smet 《Journal of Visual Communication and Image Representation》2012,23(2):287-292
An efficient disparity estimation algorithm for multi-view video sequences, recorded by a two-dimensional camera array in which the cameras are spaced equidistantly, is presented. Because of the strong geometrical relationship among views, the disparity vectors of a certain view can for most blocks be derived from the disparity vectors of other views. A frame constructed using that idea is called a D frame in this work. Three new prediction schemes which contain D frames are proposed for encoding 5 × 3 multi-view video sequences. The schemes are applied to several multi-view image sequences taken from a camera-array and they are compared in terms of quality, bit-rate and complexity. The experimental results show that the proposed prediction schemes significantly decrease the complexity of the encoder at a very low cost of quality and/or bit-rate. 相似文献
62.
《Journal of Visual Communication and Image Representation》2014,25(5):855-863
We present a bandlet-based framework for video inpainting in order to complete missing parts of a video sequence. The framework applies spatio-temporal geometric flows extracted by bandlets to reconstruct the missing data. First, a priority-based exemplar scheme enhanced by a bandlet-based patch fusion generates a preliminary inpainting result. Then, the inpainting task is completed by a 3D volume regularization algorithm which takes advantage of bandlet bases in exploiting the anisotropic regularities. The method does not need extra processes in order to satisfy visual consistency. The experimental results demonstrate the effectiveness of our proposed video completion technique. 相似文献
63.
The trend towards video streaming with increased spatial resolutions and dimensions, SD, HD, 3D, and 4kUHD, even for portable devices has important implications for displayed video quality. There is an interplay between packetization, packet loss visibility, choice of codec, and viewing conditions, which implies that prior studies at lower resolutions may not be as relevant. This paper presents two sets of experiments, the one at a Variable BitRate (VBR) and the other at a Constant BitRate (CBR), which highlight different aspects of the interpretation. The latter experiments also compare and contrast encoding with either an H.264 or an High Efficiency Video Coding (HEVC) codec, with all results recorded as objective Mean Opinion Score (MOS). The video quality assessments will be of interest to those considering: the bitrates and expected quality in error-prone environments; or, in fact, whether to use a reliable transport protocol to prevent all errors, at a cost in jitter and latency, rather than tolerate low levels of packet errors. 相似文献
64.
The three-dimensional discrete cosine transform (3D-DCT) has been researched as an alternative to existing dominant video standards based on motion estimation and compensation. Since it does not need to search macro block for inter/intra prediction, 3D-DCT has great advantages for complexity. However, it has not been developed well because of poor video quality while video standards such as H.263(+) and HEVC have been blooming. In this paper, we propose a new 3D-DCT video coding as a new video solution for low power mobile technologies such as Internet of Things (IoT) and Drone. We focus on overcoming drawbacks reported in previous research. We build a complete 3D-DCT video coding system by adopting existing advanced techniques and devising new coding algorithms to improve overall performance of 3D-DCT. Experimental results show proposed 3D-DCT outperforms H.264 low power profiles while offering less complexity. From GBD-PSNR, proposed 3D-DCT provides better performance by average 4.6 dB. 相似文献
65.
《Analytical letters》2012,45(14):1277-1282
Abstract Conventional HPLC can be simply, conveniently, and inexpensively interfaced to the electron capture detector within any GC. Various parameters have been evaluated to determine the suitability of this approach for the selective trace analysis of aliphatic and aromatic nitro derivatives. 相似文献
66.
Liang‐Wei Zheng Gwo‐Long Li Mei‐Juan Chen Chia‐Hung Yeh Kuang‐Han Tai Jian‐Sheng Wu 《ETRI Journal》2013,35(3):469-479
This paper proposes an efficient computation‐aware mode decision and search point (SP) allocation algorithm for spatial and quality scalabilities in Scalable Video Coding. In our proposal, a linear model is derived to allocate the computation for macroblocks in enhancement layers by using the rate distortion costs of the base layer. In addition, an adaptive SP decision algorithm is proposed to decide the number of SPs for motion estimation under the constraint of the allocated computation. Experiment results demonstrate that the proposed algorithm allocates the computation resource efficiently and outperforms other works in rate distortion performance under the same computational availability constraint. 相似文献
67.
The electron capture rates of 55Co and 56Ni in the ultra-strong magnetic field at four typical temperature- density points have been calculated using the nuclear shell model and Landan energy levels quantized approximate correction. The results show that the electron capture rates of 55Co and 56Ni are increased greatly in the ultra-strong magnetic field, and even exceed two orders of magnitude in the range from 4.414×10^13G to 2.207×10^27 G. The change rate of electron abundance, ye, of 55Co and 56Ni under the condition of B=4.414×10^15G in the magnetar surrounding has been calculated and discussed, the proportions of ye of 55Co and 56Ni in the total Ye have been reduced by 50 percent in all more than the condition without a magnetic field. 相似文献
68.
Multi-dimensional rate control schemes have been recently utilized to adapt video streams to dynamic network conditions and heterogeneous devices. However, current multi-dimensional rate control methods, which estimate the model coefficients using fixed update duration, usually yield inaccurate parameters for dynamically changing video content. To address this problem, a content-adaptive parameters estimation scheme is proposed for multi-dimensional rate control. Firstly, we propose to estimate the parameters using dynamical update duration based on video content and the update duration of the model coefficients is determined by jointly considering the varying picture complexity and feedback information from the actual encoding results, which can improve the model parameter estimation accuracy. Secondly, a coarse-to-fine initial parameter calculation method is proposed to refine the initial frame rate according to the channel condition and the video sequence characteristics. Extensive experimental results show that the proposed solutions outperform the state-of-the-art schemes, especially for video sequences with high temporal and spatial complexity. Furthermore, our algorithm also slightly reduces the computational complexity as compared to related algorithms. 相似文献
69.
Studies on Game Transfer Phenomena (GTP) have demonstrated that experiencing altered sensorial perceptions, automatic thoughts and behaviours after playing video games are relatively common phenomena. The aim of this paper is twofold: (i) to validate the Turkish version of the GTP scale (GTPS), and (ii) to examine the prevalence and the relation between the various dimensions of GTP (e.g., visual perceptions, thoughts, behaviours) and video game players’ individual characteristics (e.g., demographics, gaming habits). A total of 954 frequent players were recruited online. Independently of the different samples used in the original validation of the GTPS and the current study, the findings obtained via confirmatory factor analysis showed that the GTPS-Turkish is reliable and valid and proved to be adequate for measuring GTP. A total of 99% of the players in the sample had experienced some type of GTP. Moreover, the correlational, univariate and multivariate analyses showed associations between various video game player characteristics and GTP. The most remarkable finding was that the prevalence of GTP was higher among minors than adults. 相似文献
70.