This paper introduces a new class of bases, called bandelet bases, which decompose the image along multiscale vectors that are elongated in the direction of a geometric flow. This geometric flow indicates the directio...
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ISBN:
(纸本)0819450235
This paper introduces a new class of bases, called bandelet bases, which decompose the image along multiscale vectors that are elongated in the direction of a geometric flow. This geometric flow indicates the direction in which the image grey levels have regular variations. The image decomposition in a bandelet basis is implemented with a fast subband filtering algorithm. Bandelet bases lead to optimal approximation rates for geometrically regular images. For image compression, the bandelet basis geometry is optimized with a fast best basis algorithm. Comparisons are made for image compression with wavelet bases.
image forgery detection is currently one of the interested research fields of imageprocessing. Copy-Move (CM) forgery is one of the frequently used techniques. In this paper, we propose a method which is efficient an...
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ISBN:
(纸本)9781479961399
image forgery detection is currently one of the interested research fields of imageprocessing. Copy-Move (CM) forgery is one of the frequently used techniques. In this paper, we propose a method which is efficient and fast for detect copy-move regions. The proposed method accelerates block matching strategy. Firstly, the image is divided into fixed-size overlapping blocks then discrete cosine transform is applied to each block to represent its features. Fast k-means clustering technique is used to cluster the blocks into different classes. Zigzag scanning is performed to reduce the length of each block feature vector. The feature vectors of each cluster blocks are lexicographically sorted by radix sort. correlation between each nearby blocks indicates their similarity. The experimental results demonstrate that the proposed method can detect the duplicated regions efficiently, and reduce processing time up to 50% of other previous works.
There are several ways to display color data of a color image. In this paper we present different methods that we have developed in order to understand and to analyze color image information. These methods use traditi...
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ISBN:
(纸本)0819450235
There are several ways to display color data of a color image. In this paper we present different methods that we have developed in order to understand and to analyze color image information. These methods use traditional 2D and 3D visualization model associated with specific color transformation. We also introduce a new multidimensional visualization model usefull to analyse spatiocolorimetric data.
In the present work, we will first show that 3G wireless multimedia systems adopting scalable video encoding can achieve higher overall network utilization. Moreover, the problems of both packet loss and player rebuff...
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ISBN:
(纸本)0780367251
In the present work, we will first show that 3G wireless multimedia systems adopting scalable video encoding can achieve higher overall network utilization. Moreover, the problems of both packet loss and player rebuffering can degrade wireless streaming performance if the streaming video is non-scalable due to fading/retransmission and multi-user sharing. We will demonstrate that these problems can be mitigated using a scalable video with rate control. The results indicate that, MPEG-4 Simple Scalable visual Profile is more suitable for wireless video applications than Simple visual Profile.
imageprocessing operations are computational intensive and are usually solved by parallel algorithms implemented either on dedicated parallel computing devices or a network of workstations. With the increasing comput...
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ISBN:
(纸本)0819418587
imageprocessing operations are computational intensive and are usually solved by parallel algorithms implemented either on dedicated parallel computing devices or a network of workstations. With the increasing computing power of Personal Computer (PC) and better networking facilities, it is now feasible to perform distributive computing on a PC network. As the cost/performance ratio of PC is high, this provides a cost effective solution for solving imageprocessing problems. In this paper, we describe how to implement distributive imageprocessing algorithms on a peer-to-peer PC network under the WindowsNTTM operating system and the efficiency of such algorithms will be discussed.
Global motion estimation and compensation are important research issues in video compression. The main difficulty in global motion estimation resides in the disturbance of independently moving objects. The algorithm p...
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ISBN:
(纸本)0819424358
Global motion estimation and compensation are important research issues in video compression. The main difficulty in global motion estimation resides in the disturbance of independently moving objects. The algorithm presented in this paper exploits global motion information not only from stationary objects and the image background, but also from independently moving objects. Simulation results show that the new algorithm is more robust to the disturbance of independently moving objects, and computationally faster than an algorithm based on least-square approximation.
In this work we discuss several approaches fur designing fractal quantizers in the context of hybrid wavelet-fractal image compression algorithms. Moreover different subband-structures are compared concerning their su...
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ISBN:
(纸本)0819427497
In this work we discuss several approaches fur designing fractal quantizers in the context of hybrid wavelet-fractal image compression algorithms. Moreover different subband-structures are compared concerning their suitability for subsequent fractal quantization.
The objective in developing compact descriptors for visualimage search is building an image retrieval system that works efficiently and effectively under bandwidth and memory constraints. Selecting local descriptors ...
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ISBN:
(纸本)9781479902880
The objective in developing compact descriptors for visualimage search is building an image retrieval system that works efficiently and effectively under bandwidth and memory constraints. Selecting local descriptors to be processed, and sending them to the server for matching is an integral part of such a system. One such image search and retrieval system is the Compact Descriptors for visual Search (CDVS) standardization test model being developed by MPEG which has an efficient local descriptor selection criteria. However, all the existing selection parameters in CDVS are based on low-level features. In this paper, we propose two "mid-level" local descriptor selection criteria: visual Meaning Score (VMS), and visual Vocabulary Score (VVS) which can be seamlessly integrated into the existing CDVS framework. A mid-level criteria explicitly allows selection of local descriptors closer to a given set of images. Both VMS and VVS are based on visual words (patches) of images, and provide significant gains over the current CDVS standard in terms of matching accuracy, and have very low implementation cost.
This paper proposes a novel rotational method on AC coefficient pairs to embed data into a JPEG compressed image. The purpose is to improve the carrier capacity of [1] while maintaing its original feature in controlli...
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ISBN:
(纸本)9781479902880
This paper proposes a novel rotational method on AC coefficient pairs to embed data into a JPEG compressed image. The purpose is to improve the carrier capacity of [1] while maintaing its original feature in controlling quality degradation. The proposed method exploits two properties in the quantized AC coefficients, namely, large magnitude and short run of zeros for low frequency subbands, and vice versa. The coefficients are first grouped into pairs and then rotated to the left or right directions to create distinctive states, where each can be utilized to represent external data. The AC coefficients are not modified and no additional AC coefficients are introduced for data embedding. However, preprocessing is needed so that all blocks satisfy the properties assumed to ensure correct data extraction and image recovery. The proposed method is rewritable because the host image can be re-utilized without causing further distortion. Experiments were conducted to verify the basic performance of the proposed method. On average, the proposed method is able to embed up to similar to 9318 bits in the test images of quality factor 80.
Clustering tendency assessment, i.e., determining if a dataset has any inherent clusters, and if so, how many clusters, k to seek is a crucial pre-clustering task. The visual assessment of tendency (VAT) and improved ...
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ISBN:
(纸本)9781728188959
Clustering tendency assessment, i.e., determining if a dataset has any inherent clusters, and if so, how many clusters, k to seek is a crucial pre-clustering task. The visual assessment of tendency (VAT) and improved visual assessment of tendency (iVAT) algorithms provide a visual way to assess cluster tendency of a dataset by reordering the pairwise dissimilarity matrix so that potential clusters are displayed as dark blocks along the diagonal in the image of the reordered dissimilarity matrix. VAT and iVAT, being distance-based schemes, fail to perform well for datasets consisting of clusters characterized by different density levels. In this paper, we introduce two new members of the VAT family of algorithms: Locally Scaled VAT (LS-VAT) and Locally Scaled iVAT (LS-iVAT), which produces better iVAT images for data having inter-cluster density variations. Numerical experiments comparing the proposed novel approach with baseline VAT/iVAT as well as spectral clustering and density-based clustering algorithms establish that LS-VAT and LS-iVAT are superior to the comparable algorithms in terms of clustering quality.
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