Audio data in the IEEE float format is used by the professional quality audio editors as the format of choice during the editing process and also for storing the intermediate results. The proposed algorithm transforms...
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Audio data in the IEEE float format is used by the professional quality audio editors as the format of choice during the editing process and also for storing the intermediate results. The proposed algorithm transforms the floating-point values into integer values, in a completely portable way across architectures and compilers. The transform maintains all the important properties of the original values, such as magnitude relations, linear temporal relations and, most importantly, compressibility. It produces a sequence of integers and an additional binary stream used for lossless reconstruction of the original values. Furthermore, the proposed algorithm can be successfully applied to other areas such as medical, science and space data compression. Our algorithm obtains on average 7% better compression than the existing multimedia-aware compression algorithms, while being also faster.
With ever-increasing use of digital data, many applications rely on data compression for their needs related to processing, storage and communication over the network of large volumes of data. While compression saves ...
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ISBN:
(数字)9798350387131
ISBN:
(纸本)9798350387148
With ever-increasing use of digital data, many applications rely on data compression for their needs related to processing, storage and communication over the network of large volumes of data. While compression saves the memory/disk space and decreases the communication time, there is a considerable runtime spent in this process. Parallel compression algorithms and solutions that are developed to speed up the operations do not scale well on the multi-core CPUs. The data parallel schemes implemented by the prior arts are inefficient in partitioning the data and scaling the performance on the multi-core processors. Another major drawback of the existing multi-threaded compression solutions is the non-compliance to the single-threaded compression format. In this paper, we propose a set of novel and high-performance parallel compression and decompression schemes. We introduce novel designs for dynamic threading based parallel compression and random access point based parallel decompression. With our solution, we mitigate both the scaling issues on multi-core x86 CPUs and format compliance issues encountered in multi-threading the compression operations. Our test results demonstrate massive speedups by manyfolds and performance scaling never seen before on x86 CPUs especially AMD's “ZZn”-based recent processors that come with very high core counts.
The paper addresses the problem of thresholding wavelet coefficients in a transform-based algorithm for still image compression. Processing data before the quantization phase is a crucial step in a compression algorit...
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The paper addresses the problem of thresholding wavelet coefficients in a transform-based algorithm for still image compression. Processing data before the quantization phase is a crucial step in a compression algorithm, especially in applications which require high compression ratios. In the paper, after a review on the applications of wavelets to image compression, a new solution to the problem of an accurate choice of thresholds is presented. It is based on the concept of local contrast and exploits the localization properties of wavelets and a maximization of the entropy to find the optimal threshold for the wavelet coefficients. The results are compared with standard thresholding techniques which do not include considerations about local distribution of pixel information within the image. At the end, examples of compression are given, where the algorithm includes the complete processing of transform coefficients (thresholding, quantization and coding).
Transmitting compressed data can reduce inter-processor communication traffic and create new opportunities for DVS (dynamic voltage scaling) in distributed embedded systems. However, data compression alone may not be ...
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ISBN:
(纸本)9781581137620
Transmitting compressed data can reduce inter-processor communication traffic and create new opportunities for DVS (dynamic voltage scaling) in distributed embedded systems. However, data compression alone may not be effective unless coordinated with functional partitioning. This paper presents a dynamic programming technique that combines compression and functional partitioning to minimize energy on multiple voltage-scalable processors running pipelined data-regular applications under performance constraints. Our algorithm computes the optimal functional partitioning, CPU speed for each node, and their respective compression ratios. We validate the algorithm's effectiveness on a real distributed embedded system running an image processing algorithm.
Key building blocks of lossless image compression algorithms include adaptive prediction, context-based error feedback and adaptive entropy coding. This paper presents a new algorithm which includes two other building...
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ISBN:
(纸本)0818688211
Key building blocks of lossless image compression algorithms include adaptive prediction, context-based error feedback and adaptive entropy coding. This paper presents a new algorithm which includes two other building blocks-symbol mapping and context filtering. Experimental results show that the compression performance of the proposed algorithm is very close to that of CALIC and is better than that of LOGO and S+P. It is different from CALIC in the following aspects: (1) an adaptive median-FIR predictor, (2) a new error representation scheme using symbol mapping, (3) a different context calculation scheme for the prediction error, and (4) a new context filtering scheme.
An asymptotically optimal low-complexity strongly sequential compression scheme is proposed for universal lossless coding of memoryless sources with piecewise stationary abruptly changing statistics. The scheme is sho...
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An asymptotically optimal low-complexity strongly sequential compression scheme is proposed for universal lossless coding of memoryless sources with piecewise stationary abruptly changing statistics. The scheme is shown to achieve the lower bound for this universal coding problem even in a strongly sequential regime, where the horizon (i.e., the length of the data sequence to be encoded) is unknown when the algorithm starts to compress the data. Simulation results support the analytical results.
Base requirements to compression system and compression system architecture are proposed. compression processor architecture, based on random access memory is proposed in this chapter. One of the most important advant...
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Base requirements to compression system and compression system architecture are proposed. compression processor architecture, based on random access memory is proposed in this chapter. One of the most important advantages of proposed architecture is its possibility to realize it on FPGA, that simplifies testing, reduces designing time and time for putting the system into operation.
We present a fast fractal image encoding algorithm which is based on a refinement of the fractal code from an initial coarse level of the pyramid. The pyramid search algorithm is quasi-optimal in terms of minimizing t...
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We present a fast fractal image encoding algorithm which is based on a refinement of the fractal code from an initial coarse level of the pyramid. The pyramid search algorithm is quasi-optimal in terms of minimizing the mean square error. Assuming that the distribution of the matching error is described by an independent, identically distributed (i.i.d.) Laplacian random process, we derive the threshold sequence for the objective function in each pyramidal level. The computational efficiency depends on the depth of the pyramid and the search step size and could be improved up to two orders of magnitude compared with the full search of the original image.
In distributed neural network training with multiple machines and devices, communication limitations often create efficiency bottlenecks due to the frequent exchange of model parameters and gradient information betwee...
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ISBN:
(数字)9798350361834
ISBN:
(纸本)9798350361841
In distributed neural network training with multiple machines and devices, communication limitations often create efficiency bottlenecks due to the frequent exchange of model parameters and gradient information between computing nodes. This paper proposes an FPGA-based accelerator leveraging the gradient compression algorithm Top-K sparsification, which enhances performance by offloading computationally intensive compression operations to the FPGA. Experimental results demonstrate that the FPGA compression accelerator designed in this study achieves superior computing performance and compression efficiency compared to compression algorithms implemented on CPUs and GPUs. Specifically, the FPGA compresses the same amount of data 3.3-3.7 times faster than parallel solutions on CPUs and 1.3-1.8 times faster than on GPUs.
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