Correction of unfocus and misfocus via origin-centered discrete fractional fourier transform

摘要

A method corrects unfocus and misfocus in original image data using an origin-centered two-dimensional discrete fractional Fourier transform. The origin-centered two-dimensional discrete fractional Fourier transform numerically corrects a modeled evolution of an image propagating through a medium, aligning a propagation model centerline with the center of image data and the center an index-shifted numerical fractional Fourier transform operation. A zero transform-image domain origin is accordingly aligned to the center of modified image data. The corrective fractional Fourier transform power may be determined automatically or by human operator. The image correction can be applied to lens-systems or other systems obeying Fourier optics including electron microscopes, particle beams, radiation accelerators. The invention can be incorporated into cameras, film processing, photo editing software, websites, video recorders, video editing systems, surveillance systems, conferencing systems, image processing algorithms, optical computing systems, and other types of system, products and service facilities.