Implementation of fast single image Fourier ring correlation based on the paper Single image Fourier ring correlation by Bernd Rieger et. al. https://opg.optica.org/oe/fulltext.cfm?uri=oe-32-12-21767&id=551322 with massive speed improvement. Takes 25 ms to process one 16 bit 4608x2592 pixels gray scale image on a Intel Xeon Gold 6226R processor. Speed independent of image intensity.