The conventional sparse model relies on data representation in the form of vectors. It represents the vector-valued or vectorized one dimensional (1D) version of an signal as a highly sparse linear combination of basi...
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ISBN:
(纸本)9781467388511
The conventional sparse model relies on data representation in the form of vectors. It represents the vector-valued or vectorized one dimensional (1D) version of an signal as a highly sparse linear combination of basis atoms from a large dictionary. The 1D modeling, though simple, ignores the inherent structure and breaks the local correlation inside multidimensional (MD) signals. It also dramatically increases the demand of memory as well as computational resources especially when dealing with high dimensional signals. In this paper, we propose a new sparse model TenSR based on tensor for MD data representation along with the corresponding MD sparse coding and MD dictionary learning algorithms. The proposed TenSR model is able to well approximate the structure in each mode inherent in MD signals with a series of adaptive separable structure dictionaries via dictionary learning. The proposed MD sparse coding algorithm by proximal method further reduces the computational cost significantly. Experimental results with real world MD signals, i.e. 3D Multi-spectral images, show the proposed TenSR greatly reduces both the computational and memory costs with competitive performance in comparison with the state-of-the-art sparse representation methods. We believe our proposed TenSR model is a promising way to empower the sparse representation especially for large scale high order signals.
Summary form only given. Motion compensation is the key technique to reduce temporal redundancy in video coding. Interpolation filters are adopted to generate the inter frame prediction for motion compensation with fr...
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Summary form only given. Motion compensation is the key technique to reduce temporal redundancy in video coding. Interpolation filters are adopted to generate the inter frame prediction for motion compensation with fractional pixel accuracy. In existing video coding standards such as H.264/AVC and HEVC, a set of predefined interpolation filters is adopted in motion compensation. However, predefined interpolation filters cannot adapt to the video content, which may compromise the coding efficiency. In this paper, a content adaptive interpolation scheme is proposed for motion compensation. In the proposed scheme, a set of adaptive interpolation filters is derived for each frame as additional interpolation filters to minimize the inter prediction difference. Rate-distortion optimization is employed to choose between the predefined interpolation filters and the derived adaptive interpolation filters to achieve the best coding performance. The proposed scheme is implemented into the HM 12.1 software and. Experimental results show that the proposed scheme achieves 3.18 percent bit rate saving on average compared with HEVC.
Many fast integer-pixel motion estimation algorithms have been developed for the High Efficiency Video Coding Standard, however the speed of sub-pixel motion estimation still has room for improvement. A fast sub-pixel...
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ISBN:
(纸本)9781479953424
Many fast integer-pixel motion estimation algorithms have been developed for the High Efficiency Video Coding Standard, however the speed of sub-pixel motion estimation still has room for improvement. A fast sub-pixel motion estimation algorithm is proposed in this paper to speed up the sub-pixel search process. First, the proposed scheme skips sub-pixel search process in smooth prediction units. Then a fast sub-pixel search algorithm based on texture direction analysis is proposed to further reduce the computational complexity of subpixel motion estimation. The simulation results show that compared with the Full Sub-pixel Search (FSPS), the encoding complexity of the whole motion estimation process can be reduced by an average of 40.9% with negligible coding performance loss.
Because of everyone's involvement in social networks, social networks are full of massive multimedia data, and events are got released and disseminated through social networks in the form of multi-modal and multi-att...
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Because of everyone's involvement in social networks, social networks are full of massive multimedia data, and events are got released and disseminated through social networks in the form of multi-modal and multi-attribute heterogeneous data. There have been numerous researches on social network search. Considering the spatio-temporal feature of messages and social relationships among users, we summarized an overall social network search framework from the perspective of semantics based on existing researches. For social network search, the acquisition and representation of spatio-temporal data is the basis, the semantic analysis and modeling of social network cross-media big data is an important component, deep semantic learning of social networks is the key research field, and the indexing and ranking mechanism is the indispensable part. This paper reviews the current studies in these fields, and then main challenges of social network search are given. Finally, we give an outlook to the prospect and further work of social network search.
Resource location strategy has become very popular for mass data distribution in complex and dynamic network. Searching for the objects is a fundamental problem to unstructured Peer to peer(P2P) networks. In this pape...
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Resource location strategy has become very popular for mass data distribution in complex and dynamic network. Searching for the objects is a fundamental problem to unstructured Peer to peer(P2P) networks. In this paper, we propose a resource location strategy for user requirements, which employs the collaborative exchange of information between peers to construct interest communities. This strategy can gather similar peers and disseminate useful information among them. Furthermore, we design an algorithm in unstructured P2 P systems named Appropriate degree gossip search algorithm(ADGSA). Using this search algorithm, the performance including search success ratio, recall rate and search response time has been improved dramatically. An efficient resource location system with a fast organization of users cluster based on their requirements can be provided, preventing the creation of unliked communities. The simulation results show that our strategy has better search efficiency, short response time and high recall ratio.
Sparse representation based anomaly detection algorithms have received a widely interest in recent ***,most of the existing approaches fail to pay attention to the manifold structure of the video data,which has been p...
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ISBN:
(纸本)9781509001668
Sparse representation based anomaly detection algorithms have received a widely interest in recent ***,most of the existing approaches fail to pay attention to the manifold structure of the video data,which has been pointed to be important for data *** overcome this limitation,we develop a new sparse coding algorithm named constrained sparse representation(CSR) for video anomaly detection,which explicitly takes the manifold structure of data into *** assumes that each sample's sparse coding coefficient can be linearly reconstructed by the coding coefficients of its ***,CSR algorithm can obtain relatively smoothly sparse representations along the manifold of *** apply the proposed CSR model to video abnormal event detection task and conduct extensive experiments on the UMN *** experimental results demonstrate that our proposed CSR model performed better than some related algorithms.
With the rapid development of technologies, such as cloud computing, big data and so forth, tourism big data has drawn the attention of many scholars. How to make full use of a large amount of raw data from tourism ac...
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In recent years, accidents occur frequently because the people number of scenic spots is lack of control. In this paper, a novel real-time people number detection algorithm of scenic spot based on density center clust...
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Micro-credit companies mushroomed in China in recent years. Those companies are requiring a much more efficient and accurate way to assess credit risk. Therefore, there is a growing trend in applying machine learning ...
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Based on the fact that tourism photos on the Internet have a lot of additional information, we proposed a novel tourism image retrieval method based on hypergraph(HMIR). The proposed method utilizes hypergraph to esta...
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ISBN:
(纸本)9781509012572
Based on the fact that tourism photos on the Internet have a lot of additional information, we proposed a novel tourism image retrieval method based on hypergraph(HMIR). The proposed method utilizes hypergraph to establish the relationship among different types of low-level visual features of images and their additional information(such as shooting locations, user-defined tags, etc.), and the fusion of different features is then performed at the offline indexing stage using random walk and similar image set(SI) replacement. Then Bag of Words method is used for image retrieval at online query stage. During online retrieval stage, we only need to extract local descriptors from queries, and can get semantic-aware retrieval results. Experiments show that compared with several other image retrieval methods based on single feature or multiple feature, the proposed method can improve the performance of image retrieval using different evaluation methods.
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