Object tracking from speckle fields using optical vortices and optical flow demon algorithm

ASTRID LORENA VILLAMIZAR AMADO; ALEJANDRO VELEZ ZEA; MYRIAN TEBALDI

San Jose

Congreso; RIAO OPTILAS 2023; 2023

Object tracking from speckle fields is a common problem in many imaging techniques, rangingfrom holographic microscopy to magnetic resonance and ultrasound ecograms. A broad range ofalgorithms and methods have been proposed and demonstrated to achieve fast and accurateobject tracking. Amongst these methods, we find optical flow approaches, which measure andtrack the flow of intensity changes in an image in a per pixel basis. These approaches, while verycapable, cannot measure subpixel movements, and are particularly susceptible to noise andintensity changes. As an alternative to optical flow methods, we find optical vortex metrology.Optical vortex metrology relies in identifying and tracking phase singularities or optical vorticesthat appear in the pseudo phase information generated using Laguerre-Gauss transformations ofan input intensity data. The optical vortices have core properties that allow to indenty and theirtrack them as their position as the scene changes.In this work, we use an optical flow method based in the demon algorithm to track the movementof an object from an experimentally recorded speckle field. Then, we perform the procedure withan optical vortex technique using the Laguerre-Gauss transform. The parameters used in opticalvortex tracking are calibrated and optimized using the optical flow method results as reference.