Intensity Correction of Fluorescent Confocal Laser Scanning Microscope Images by Mean-Weight Filtering.

Sang-Chul Lee and Peter Bajcsy

Journal of Microscopy 221 p122-136 (2006)

This paper addresses the problem of intensity correction of fluorescent confocal laser scanning microscope (CLSM) images. CLSM images are frequently used in medical domain for obtaining 3D information about specimen structures by imaging a set of 2D cross sections and performing 3D volume reconstruction afterwards. However, 2D images acquired from fluorescent CLSM images demonstrate significant intensity heterogeneity, for example, due to photo-bleaching and fluorescent attenuation in depth. We developed an intensity heterogeneity correction technique that (a) adjusts intensity heterogeneity of 2D images, (b) preserves fine structural details, and (c) enhances image contrast, by performing spatially adaptive mean-weight filtering. Our solution is obtained by formulating an optimization problem, followed by filter design and automated selection of filtering parameters. The proposed filtering method is experimentally compared with several existing techniques by using four quality metrics, such as contrast, intensity heterogeneity (entropy) in low frequency domain, intensity distortion in high frequency domain and saturation. Based on our experiments and the four quality metrics, the developed mean-weight filtering outperforms other intensity correction methods by at least a factor of 1.5 when applied to fluorescent CLSM images.