Parallel computing of a digital hologram and particle searching for microdigital-holographic particle-tracking velocimetry

Abstract

We have developed a parallel algorithm for microdigital-holographic particle-tracking velocimetry. The algorithm is used in (1) numerical reconstruction of a particle image computer using a digital hologram, and (2) searching for particles. The numerical reconstruction from the digital hologram makes use of the Fresnel diffraction equation and the FFT (fast Fourier transform), whereas the particle search algorithm looks for local maximum graduation in a reconstruction field represented by a 3D matrix. To achieve high performance computing for both calculations (reconstruction and particle search), two memory partitions are allocated to the 3D matrix. In this matrix, the reconstruction part consists of horizontally placed 2D memory partitions on the x-y plane for the FFT, whereas, the particle search part consists of vertically placed 2D memory partitions set along the z axes. Consequently, the scalability can be obtained for the proportion of processor elements, where the benchmarks are carried out for parallel computation by a SGI Altix machine.

Polycarbonate as an Elasto-Plastic Material Model for Simulation of the Microstructure Hot Imprint Process

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Particle Tracking Velocimetry for indoor airflow field: A review

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Digital holography of particles: benefits of the ‘inverse problem’ approach

“…The complexity of hologram processing, bounded by that of the 3D reconstruction step, remains time-consuming for an industrial framework use. Recently, some solutions as parallel computing [33] or even some implementations in dedicated circuits as FPGA (Field-Programmable Gate Array) [34] have been proposed in order to reduce this problem. Direct processing approaches that do not require 3D reconstruction were also suggested to quickly extract the mean particle size [35] or the distribution of directions of fibres [36].…”