1037852
Smart rebinning for the compression of concentric mosaic
The concentric mosaic offers a quick solution to construct a virtual copy of a real environment, and to navigate in that virtual environment. However, the huge amount of data associated with the concentric mosaic is a heavy burden for its application. A three-dimensional (3D) wavelet-based compressor has been proposed in a previous work to compress the concentric mosaic. In this paper, we greatly improve the compression efficiency of the 3D wavelet coder by a data rearrangement mechanism called "smart rebinning". The proposed scheme first aligns the concentric mosaic image shots along the horizontal direction and then rebins the shots into multiperspective panoramas. Smart rebinning effectively enhances the correlation in the 3D data volume, translating the data into a representation that is more suitable for 3D wavelet compression. Experimental results show that the performance of the 3D wavelet coder is improved by an average of 4.3 dB with the use of the smart rebinning. The proposed coder outperforms MPEG-2 coding of the concentric mosaic by an average of 3.7 dB.
9584655
Arbitrarily shaped video-object coding by wavelet
Video-object coding is one of the most important functionalities proposed by MPEG-4. We propose a new wavelet method to encode the texture of an arbitrarily shaped object, both for the still and for the video-object. The method uses the shape adaptive wavelet transform (SA-DWT) in MPEG-4 still object coding, but with a computationally more efficient lifting implementation. The transformed object coefficients are then quantized and entropy encoded with a partial bit-plane embedded coder, which greatly improves the coding efficiency. We denote the coding algorithm as the video-object wavelet (VOW) coder. Experimental results show that VOW significantly outperforms MPEG-4 in still-object coding, and achieves a comparable performance in video-object coding in terms of PSNR. Moreover, the VOW decoded object looks better subjectively, with less annoying blocking artifacts than that of MPEG-4.
7011807
Distributed hosting of Web content with erasure coding and unequal weight assignment
By sharing and hosting personal Web content in a peer-to-peer (P2P) fashion, we may increase the bandwidth of retrieval and improve the reliability of retrieval. The cost is that the Web content has to be replicated to and stored in the peers, consuming valuable network bandwidth and peer storage space. In this work, we develop two technologies, namely hierarchical content organization with unequal weight assignment and erasure coding, to reduce the amount of content to be distributed, yet still maintain the retrieval speed up and reliability. Significant improvement over the ordinary Web server is demonstrated.
2120901
An embedded still image coder with rate-distortion optimization
It is well known that the fixed rate coder achieves optimality when all coefficients are coded with the same rate-distortion (R-D) slope. In this paper, we show that the performance of the embedded coder can be optimized in a rate-distortion sense by coding the coefficients with decreasing R-D slope. We denote such a coding strategy as rate-distortion optimized embedding (RDE). RDE allocates the available coding bits first to the coefficient with the steepest R-D slope, i.e., the largest distortion decrease per coding bit. The resultant coding bitstream can be truncated at any point and still maintain an optimal R-D performance. To avoid the overhead of coding order transmission, we use the expected R-D slope, which can be calculated from the coded bits and is available in both the encoder and the decoder. With the probability estimation table of the QM-coder, the calculation of the R-D slope can be just a lookup table operation. Experimental results show that the rate-distortion optimization significantly improves the coding efficiency in a wide bit rate range.
14407633
The seamlessly multiplexed embedded codec (SMEC) and its application in image coding
The landmark JPEG 2000 image compression standard offers not only superior compression performance, but also incredible flexibility. The compressed bitstream of JPEG 2000 can be flexibly reorganized to another bitstream of different bitrate, resolution, and spatial region of interest (ROI) or a combination of any of the above. Such flexibility is achieved by multiplexing the compressed bitstream pieces of multiple code-blocks together into a combined bitstream, with the length of the code-block bitstream piece (LOCB) embedded in the combined bitstream. The LOCB serves both to reorganize the bitstream, and to decode the bitstream. It represents a significant overhead, especially since there is no correlation between the neighbor LOCBs. In this work, we introduce seamless multiplexing, and separate the information needed for the reorganization, i.e., the LOCB, from the compressed bitstream itself by using the decoder pointer to multiplex the bitstream pieces. As a result, the compressed bitstream consists of code-block bitstream pieces seamlessly concatenated to each other. With seamless multiplexing, only the compressed bitstream (without LOCB) needs to be delivered to the receiving client. It results in better compression performance and higher granularity of access. Another benefit of seamless multiplexing is that the relative coding orders of the code-blocks are preserved in the bitstream reorganization. As a result, the seamlessly multiplexed embedded codec (SMEC) may utilize the dependencies among the code-blocks in the coding, thus further boost the compression performance.
6980354
Image compression with a hybrid wavelet-fractal coder
A hybrid wavelet-fractal coder (WFC) for image compression is proposed. The WFC uses the fractal contractive mapping to predict the wavelet coefficients of the higher resolution from those of the lower resolution and then encode the prediction residue with a bitplane wavelet coder. The fractal prediction is adaptively applied only to regions where the rate saving offered by fractal prediction justifies its overhead. A rate-distortion criterion is derived to evaluate the fractal rate saving and used to select the optimal fractal parameter set for WFC. The superior performance of the WFC is demonstrated with extensive experimental results.
15000115
Direct interesting rule generation
An association rule generation algorithm usually generates too many rules including a lot of uninteresting ones. Many interestingness criteria are proposed to prune those uninteresting rules. However, they work in post-pruning process and hence do not improve the rule generation efficiency. We discuss properties of informative rule set and conclude that the informative rule set includes all interesting rules measured by many commonly used interestingness criteria, and that rules excluded by the informative rule set are forwardly prunable, i.e. they can be removed in the rule generation process instead of post pruning. Based on these properties, we propose a direct interesting rule generation algorithm, DIG, to directly generate interesting rules defined by any of 12 interestingness criteria. We further show experimentally that DIG is faster and uses less memory than Apriori.
13983488
Text and picture segmentation by the distribution analysis of wavelet coefficients
This paper presents an algorithm to segment text and picture in an image using two features based on the statistical distribution of the wavelet coefficients in high frequency bands. The algorithm breaks the image into blocks and classifies every block as background, text or picture according to the two features. The block size is variable so that the segmentation can be accurate at the boundary of two types and avoids misclassifying due to over-localized region analysis.
198665
Enhanced smart-card based license management
In many e-commerce (electronic commerce) situations, the owner of a digital object wants to enforce policies on the object after the object is in the customer's hands. The object can be thought of as being software, because data is often protected by forcing access to it to take place through a particular authorized software (e.g., a "reader" for an encrypted media file, in which case a license to view the movie is, in some sense, a "software license"). One of the ways that were proposed for such policy enforcement is the use of smart cards. We describe an enhanced solution to software license management based on tamper-resistant smart cards. Our public-key protocols for binding software licenses to smart cards improve on previous schemes in that they support flexible and partial transfers of licenses between cards. The license is verified by checking the presence of the associated card. The user can therefore have several software licenses all of which are bound to one card, to avoid juggling several cards in and out of the card reader.
12265537
Probabilistic models for discovering e-communities
The increasing amount of communication between individuals in e-formats (e.g. email, Instant messaging and the Web) has motivated computational research in social network analysis (SNA). Previous work in SNA has emphasized the social network (SN) topology measured by communication frequencies while ignoring the semantic information in SNs. In this paper, we propose two generative Bayesian models for semantic community discovery in SNs, combining probabilistic modeling with community detection in SNs. To simulate the generative models, an EnF-Gibbs sampling algorithm is proposed to address the efficiency and performance problems of traditional methods. Experimental studies on Enron email corpus show that our approach successfully detects the communities of individuals and in addition provides semantic topic descriptions of these communities.
42687859
An intrinsic evolvable and online adaptive evolvable fuzzy hardware scheme for packet switching network
Most published works usually focused on extrinsic evolvable hardware (EHW), and in some instances, intrinsic but offline adaptive EHW. In this paper, we describe an intrinsic evolvable and online adaptive EHW to solve packet switching problem. Based on the coding and evolution scheme, we refer to it as evolvable fuzzy hardware (EFH), an extension of our proposed evolvable fuzzy system (EFS) by Li and Lim (2003) and reconfigurable fuzzy inference chip (RFIC) by Cao et. al. EFH is a good framework for intrinsic evolvability and online adaptation.