title: Non-rigid registration and non-local principle component analysis to improve electron microscopy spectrum images.
abstract: Image registration and non-local Poisson principal component analysis (PCA) denoising improve the quality of characteristic x-ray (EDS) spectrum imaging of Ca-stabilized Nd2/3TiO3 acquired at atomic resolution in a scanning transmission electron microscope. Image registration based on the simultaneously acquired high angle annular dark field image significantly outperforms acquisition with a long pixel dwell time or drift correction using a reference image. Non-local Poisson PCA denoising reduces noise more strongly than conventional weighted PCA while preserving atomic structure more faithfully. The reliability of and optimal internal parameters for non-local Poisson PCA denoising of EDS spectrum images is assessed using tests on phantom data.
authors.affiliation: Department of Materials Science and Engineering, The University of Wisconsin-Madison, 1509 University Avenue, Madison, WI 53706, USA.
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Yankovich
authors.forename: Chenyu
authors.initials: C
authors.lastname: Zhang
authors.forename: Albert
authors.initials: A
authors.lastname: Oh
authors.forename: Thomas J A
authors.initials: TJ
authors.lastname: Slater
authors.forename: Feridoon
authors.initials: F
authors.lastname: Azough
authors.forename: Robert
authors.initials: R
authors.lastname: Freer
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Haigh
authors.forename: Rebecca
authors.initials: R
authors.lastname: Willett
authors.forename: Paul M
authors.initials: PM
authors.lastname: Voyles