A Channel Differential EZW Coding Scheme for EEG Data Compression

2011 ◽  
Vol 15 (6) ◽  
pp. 831-838 ◽  
Author(s):  
V. R. Dehkordi ◽  
H. Daou ◽  
F. Labeau
1997 ◽  
Vol 44 (2) ◽  
pp. 105-114 ◽  
Author(s):  
G. Antoniol ◽  
P. Tonella
Keyword(s):  

2015 ◽  
Vol 12 (1) ◽  
pp. 49-62 ◽  
Author(s):  
Darius Birvinskas ◽  
Vacius Jusas ◽  
Ignas Martisius ◽  
Robertas Damasevicius

Electroencephalography (EEG) is widely used in clinical diagnosis, monitoring and Brain - Computer Interface systems. Usually EEG signals are recorded with several electrodes and transmitted through a communication channel for further processing. In order to decrease communication bandwidth and transmission time in portable or low cost devices, data compression is required. In this paper we consider the use of fast Discrete Cosine Transform (DCT) algorithms for lossy EEG data compression. Using this approach, the signal is partitioned into a set of 8 samples and each set is DCT-transformed. The least-significant transform coefficients are removed before transmission and are filled with zeros before an inverse transform. We conclude that this method can be used in real-time embedded systems, where low computational complexity and high speed is required.


Author(s):  
Ning Ma

AbstractThe emergence of multimedia data has enriched people’s lives and work and has penetrated into education, finance, medical, military, communications, and other industries. The text data takes up a small space, and the network transmission speed is fast. However, due to its richness, the multimedia data makes it occupy an ample space. Some high-definition multimedia information even reaches the GB level, and the multimedia data network transmission is relatively slow. Compared with the traditional scalar data, the multimedia data better describes the characteristics of the transaction, but at the same time, the multimedia data itself has a large capacity and must be compressed. Nodes of wireless multimedia sensor networks have limited ability to process data. Traditional data compression schemes require high processing power of nodes and are not suitable for sensor networks. Therefore, distributed video codec scheme in recent years becomes one of the hot multimedia sensor network technologies, which is a simple coding scheme, coding complexity of decoding performance. In this paper, distributed video codec and its associated knowledge based on the study present a distributed video coding scheme and its improvements. Aiming at the problem that the traditional distributed video coding scheme cannot accurately decode the motion severe region and the boundary region, a distributed video coding algorithm based on gradient-domain ROI is proposed, which can enhance the coding efficiency of the severe motion region and improve the decoded image while reducing the code rate and quality, ultimately reducing sensor node energy consumption.


2015 ◽  
Vol 11 (21) ◽  
pp. 221-238 ◽  
Author(s):  
Carlos Fajardo ◽  
Oscar Mauricio Reyes ◽  
Ana Ramirez

Different seismic data compression algorithms have been developed in or-der to make the storage more efficient, and to reduce both the transmission time and cost. In general, those algorithms have three stages: transforma-tion, quantization and coding. The Wavelet transform is highly used tocompress seismic data, due to the capabilities of the Wavelets on representing geophysical events in seismic data. We selected the lifting scheme to implement the Wavelet transform because it reduces both computational and storage resources. This work aims to determine how the transforma-tion and the coding stages affect the data compression ratio.Several 2Dlifting-based algorithms were implemented to compress three different seis-mic data sets. Experimental results obtained for different filter type, filterlength, number of decomposition levels and coding scheme, are presented in this work.


1996 ◽  
Vol 10 (4) ◽  
pp. 465-486 ◽  
Author(s):  
Ilan Sadeh

A practical source coding scheme based on approximate string matching is proposed. It is an approximate fixed-length string matching data compression combined with a block-coder based on the empirical distribution. A lemma on approximate string matching, which is an extension of the Kac Lemma, is proved. It is shown, based on the lemma, that the deterministic algorithm converts the stationary and ergodic source, u, into an output process v, and under the assumption that v is a stationary process, after the scheme has run for an infinite time, the optimal compression ratio R(D) is achieved. This reduces the problem of the universal lossy coder to the proof of stationarity of the output process ν in the proposed algorithm. The main advantages of the proposed method are the asymptotic sequential behavior of the encoder and the simplicity of the decoder.


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