Backoach Ohad, Kariv Saar, Girshovitz Pinhas, Shaked Natan T
Opt Express. 2016 Feb 22;24(4):3177-88. doi: 10.1364/OE.24.003177.
We present parallel processing implementation for rapid extraction of the quantitative phase maps from off-axis holograms on the Graphics Processing Unit (GPU) of the computer using computer unified device architecture (CUDA) programming. To obtain efficient implementation, we parallelized both the wrapped phase map extraction algorithm and the two-dimensional phase unwrapping algorithm. In contrast to previous implementations, we utilized unweighted least squares phase unwrapping algorithm that better suits parallelism. We compared the proposed algorithm run times on the CPU and the GPU of the computer for various sizes of off-axis holograms. Using the GPU implementation, we extracted the unwrapped phase maps from the recorded off-axis holograms at 35 frames per second (fps) for 4 mega pixel holograms, and at 129 fps for 1 mega pixel holograms, which presents the fastest processing framerates obtained so far, to the best of our knowledge. We then used common-path off-axis interferometric imaging to quantitatively capture the phase maps of a micro-organism with rapid flagellum movements.
我们展示了一种并行处理实现方法，用于在计算机的图形处理单元（GPU）上，使用计算机统一设备架构（CUDA）编程，从离轴全息图中快速提取定量相位图。为了实现高效处理，我们对包裹相位图提取算法和二维相位解包裹算法都进行了并行化处理。与之前的实现方法不同，我们采用了更适合并行性的非加权最小二乘相位解包裹算法。我们比较了所提出算法在计算机的CPU和GPU上针对各种尺寸离轴全息图的运行时间。使用GPU实现方法，对于400万像素的全息图，我们以每秒35帧（fps）的速度从记录的离轴全息图中提取解包裹相位图；对于100万像素的全息图，提取速度为每秒129帧，据我们所知，这是目前获得的最快处理帧率。然后，我们使用共光路离轴干涉成像来定量捕获具有快速鞭毛运动的微生物的相位图。
