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Wavelet-based image restoration for compact X-ray microscopy.

H Stollberg·J Boutet de Monvel·A Holmberg·H M Hertz
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Abstract

Compact water-window X-ray microscopy with short exposure times will always be limited on photons owing to sources of limited power in combination with low-efficency X-ray optics. Thus, it is important to investigate methods for improving the signal-to-noise ratio in the images. We show that a wavelet-based denoising procedure significantly improves the quality and contrast in compact X-ray microscopy images. A non-decimated, discrete wavelet transform (DWT) is applied to original, noisy images. After applying a thresholding procedure to the finest scales of the DWT, by setting to zero all wavelet coefficients of magnitude below a prescribed value, the inverse DWT to the thresholded DWT produces denoised images. It is concluded that the denoising procedure has potential to reduce the exposure time by a factor of 2 without loss of relevant image information.

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AlgorithmsArtifactsDiatomsImage EnhancementMicroscopyMicroscopy, Electron, ScanningSignal Processing, Computer-AssistedX-RaysEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

H Stollberg, J Boutet de Monvel, A Holmberg, H M Hertz. 2003. Wavelet-based image restoration for compact X-ray microscopy.. https://doi.org/10.1046/j.1365-2818.2003.01211.x

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