Improved spark and ember detection using stationary wavelet transforms

JOURNAL OF THEORETICAL BIOLOGY

卷:264

Article

Szabo, Laszlo Zsolt^1,2  Vincze, Janos¹  Csernoch, Laszlo¹  Szentesi, Peter¹ 

[1] Univ Debrecen, Dept Physiol, Med & Hlth Sci Ctr, H-4012 Debrecen, Hungary

[2] Sapientia Hungarian Univ Transylvania, Dept Elect Engn, Targu Mures, Romania

关键词: Calcium spark;    Ember;    Automatic detection;    Wavelet analysis;   

DOI  :  10.1016/j.jtbi.2010.04.005

来源: Elsevier

【 摘 要 】

Calcium sparks and embers are localized intracellular events of calcium release in muscle cells studied frequently by confocal microscopy using line-scan imaging The large quantity of images and large number of events require automatic detection procedures based on signal processing methods. In the past decades these methods were based on thresholding procedures Although, recently, wavelet transforms were also introduced, they have not become widespread We have implemented a set of algorithms based on one- and two-dimensional versions of the a trous wavelet transform The algorithms were used to perform spike filtering, denoising and detection procedures Due to the dependence of the algorithms on user adjustable parameters, their effect on the efficiency of the algorithm was studied in detail We give methods to avoid false positive detections which are the consequence of the background noise in confocal images In order to establish the efficiency and reliability of the algorithms, various tests were performed on artificial and experimental images. Spark parameters (amplitude, full width-at-half maximum) calculated using the traditional and the wavelet methods were compared We found that the latter method is capable of identifying more events with better accuracy on experimental images Furthermore, we extended the wavelet-based transform from calcium sparks to long-lasting small-amplitude events as calcium embers The method not only solved their automatic detection but enabled the identification of events with small amplitude that otherwise escaped the eye. rendering the determination of their characteristic parameters more accurate (C) 2010 Elsevier Ltd All rights reserved

【 授权许可】

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