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This work presents a versatile digital holography software (HOLO4D) that provides an all-in-one solution for holographic reconstruction, simulation, de-twining and lens distortion removal in a user-friendly graphical interface. The software accepts holograms for both, in-line and off-axes schemes with the option to locate and specify the cross-term in the latter case. Both amplitude and phase shifts are recovered from holograms generated by plane waves using multiple functionalities for propagation. These include the angular spectrum method, sinc-interpolation, upsampling-lowpass filter and zero-padding processes that can be applied in a variety of combinations to optimize holographic reconstructions. The virtual image that obscures the real image in these reconstructions is suppressed using a subtraction division plus mean (SDPM) normalization procedure or by iteratively updating the complex-valued wavefront in the detector plane. The use of lenses to manipulate the effective position of the hologram introduces optical distortions. These are removed by calibrating a dot-pattern hologram reconstruction in a step-by-step auto-detection procedure and mapping the distortion characteristics to the corresponding object hologram reconstruction. Hologram simulations enable determining the maximum field-of-view, fringes captured, and the lateral resolution possible based on the imaging sensor, illumination and setup specifications. The numerical package is used to process holograms of 80 μm thick hair strands, scan the depth-of-field and locate the precise three-dimensional (3D) location of reconstructed objects. The results demonstrate the versatility of the software to reconstruct, de-twin, undistort and simulate holograms in a user friendly manner and its applicability as a robust tool for 3D visualization, education, and holographic research.
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