title: An adaptive non-local means filter for denoising live-cell images and improving particle detection.
abstract: Fluorescence imaging of dynamical processes in live cells often results in a low signal-to-noise ratio. We present a novel feature-preserving non-local means approach to denoise such images to improve feature recovery and particle detection. The commonly used non-local means filter is not optimal for noisy biological images containing small features of interest because image noise prevents accurate determination of the correct coefficients for averaging, leading to over-smoothing and other artifacts. Our adaptive method addresses this problem by constructing a particle feature probability image, which is based on Haar-like feature extraction. The particle probability image is then used to improve the estimation of the correct coefficients for averaging. We show that this filter achieves higher peak signal-to-noise ratio in denoised images and has a greater capability in identifying weak particles when applied to synthetic data. We have applied this approach to live-cell images resulting in enhanced detection of end-binding-protein 1 foci on dynamically extending microtubules in photo-sensitive Drosophila tissues. We show that our feature-preserving non-local means filter can reduce the threshold of imaging conditions required to obtain meaningful data.
authors.affiliation: Department of Physics, Heriot-Watt University, Edinburgh EH14 4AS, UK. trilithy@gmail.com
authors.forename: Lei
authors.initials: L
authors.lastname: Yang
authors.forename: Richard
authors.initials: R
authors.lastname: Parton
authors.forename: Graeme
authors.initials: G
authors.lastname: Ball
authors.forename: Zhen
authors.initials: Z
authors.lastname: Qiu
authors.forename: Alan H
authors.initials: AH
authors.lastname: Greenaway
authors.forename: Ilan
authors.initials: I
authors.lastname: Davis
authors.forename: Weiping
authors.initials: W
authors.lastname: Lu
mesh_terms: D000465:Algorithms; D000818:Animals; D004330:Drosophila / Q000378:metabolism*; D008856:Microscopy, Fluorescence / Q000379:methods*; D008870:Microtubules / Q000378:metabolism; D012815:Signal Processing, Computer-Assisted