Cryo-Electron Microscopy Image Denoising Using Multi-Frequency Vector Diffusion Maps

Cryo-electron microscopy (EM) single particle reconstruction is a general technique for 3D structure determination of macromolecules. However, because the images are taken at low electron dose, it is extremely hard to visualize the individual particle with low contrast and high noise level. In this paper, we propose a novel framework for cryo-EM single particle image denoising, which incorporates the recently developed multi-frequency vector diffusion maps for improving the identification and alignment of images with similar viewing directions. In addition, we propose a novel filtering scheme combining graph signal processing and truncated Fourier-Bessel expansion of the projection images. Through both simulated and publicly available real data, we demonstrate that our proposed method is efficient and robust to noise compared with the state-of-the-art cryo-EM 2D class averaging algorithms.