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arXiv · 1501.06254

Combining $2D$ synchrosqueezed wave packet transform with optimization for crystal image analysis

Jianfeng Lu·Benedikt Wirth·Haizhao Yang
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Abstract

We develop a variational optimization method for crystal analysis in atomic resolution images, which uses information from a 2D synchrosqueezed transform (SST) as input. The synchrosqueezed transform is applied to extract initial information from atomic crystal images: crystal defects, rotations and the gradient of elastic deformation. The deformation gradient estimate is then improved outside the identified defect region via a variational approach, to obtain more robust results agreeing better with the physical constraints. The variational model is optimized by a nonlinear projected conjugate gradient method. Both examples of images from computer simulations and imaging experiments are analyzed, with results demonstrating the effectiveness of the proposed method.

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Jianfeng Lu, Benedikt Wirth, Haizhao Yang. 2015-01-26. Combining $2D$ synchrosqueezed wave packet transform with optimization for crystal image analysis. https://doi.org/10.1016/j.jmps.2016.01.002

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