Improved spark and ember detection using stationary wavelet transforms

László Zsolt Szabó, János Vincze, L. Csernoch, P. Szentesi

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

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 à 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.

Original languageEnglish
Pages (from-to)1279-1292
Number of pages14
JournalJournal of Theoretical Biology
Volume264
Issue number4
DOIs
Publication statusPublished - Jun 2010

Fingerprint

Wavelet Analysis
Electric sparks
Wavelet transforms
Wavelet Transform
Calcium
automatic detection
calcium
Wavelets
Calcium Signaling
methodology
Confocal microscopy
rendering
Confocal Microscopy
Full width at half maximum
processing technology
Confocal
myocytes
Muscle
Thresholding
Denoising

Keywords

  • Automatic detection
  • Calcium spark
  • Ember
  • Wavelet analysis

ASJC Scopus subject areas

  • Medicine(all)
  • Immunology and Microbiology(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)
  • Modelling and Simulation
  • Statistics and Probability
  • Applied Mathematics

Cite this

Improved spark and ember detection using stationary wavelet transforms. / Szabó, László Zsolt; Vincze, János; Csernoch, L.; Szentesi, P.

In: Journal of Theoretical Biology, Vol. 264, No. 4, 06.2010, p. 1279-1292.

Research output: Contribution to journalArticle

Szabó, László Zsolt ; Vincze, János ; Csernoch, L. ; Szentesi, P. / Improved spark and ember detection using stationary wavelet transforms. In: Journal of Theoretical Biology. 2010 ; Vol. 264, No. 4. pp. 1279-1292.
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