Improving chemical mapping algorithm and visualization in full-field hard x-ray spectroscopic imaging

Cheng Chang; Wei Xu; Yu-chen Karen Chen-Wiegart; Jun Wang; Dantong Yu

doi:10.1117/12.2041109

3 February 2014 Improving chemical mapping algorithm and visualization in full-field hard x-ray spectroscopic imaging

Cheng Chang, Wei Xu, Yu-chen Karen Chen-Wiegart, Jun Wang, Dantong Yu

Proceedings Volume 9017, Visualization and Data Analysis 2014; 90170S (2014) https://doi.org/10.1117/12.2041109
Event: IS&T/SPIE Electronic Imaging, 2014, San Francisco, California, United States

Abstract

X-ray Absorption Near Edge Structure (XANES) imaging, an advanced absorption spectroscopy technique, at the Transmission X-ray Microscopy (TXM) Beamline X8C of NSLS enables high-resolution chemical mapping (a.k.a. chemical composition identification or chemical spectra fitting). Two-Dimensional (2D) chemical mapping has been successfully applied to study many functional materials to decide the percentages of chemical components at each pixel position of the material images. In chemical mapping, the attenuation coefficient spectrum of the material (sample) can be fitted with the weighted sum of standard spectra of individual chemical compositions, where the weights are the percentages to be calculated. In this paper, we first implemented and compared two fitting approaches: (i) a brute force enumeration method, and (ii) a constrained least square minimization algorithm proposed by us. Next, as 2D spectra fitting can be conducted pixel by pixel, so theoretically, both methods can be implemented in parallel. In order to demonstrate the feasibility of parallel computing in the chemical mapping problem and investigate how much efficiency improvement can be achieved, we used the second approach as an example and implemented a parallel version for a multi-core computer cluster. Finally we used a novel way to visualize the calculated chemical compositions, by which domain scientists could grasp the percentage difference easily without looking into the real data.

Citation Download Citation

Cheng Chang, Wei Xu, Yu-chen Karen Chen-Wiegart, Jun Wang, and Dantong Yu "Improving chemical mapping algorithm and visualization in full-field hard x-ray spectroscopic imaging", Proc. SPIE 9017, Visualization and Data Analysis 2014, 90170S (3 February 2014); https://doi.org/10.1117/12.2041109

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available