Evaluation of the plankton species coordinates from digital holographic video

摘要

Procedures of evaluating the plankton species coordinates from their holographic video are suggested. The longitudinal coordinate is determined by the position of the best particle image plane reconstructed from a holographic video frame (a hologram). The position of the best image plane is refined based on maximum values of the quality criteria - the boundary contrast and the boundary brightness jump. The wall effect, that is, the influence of the optical water-glass-air system is considered to refine the longitudinal coordinate. The coordinates of the center of gravity of the particle image are taken as the transverse particle coordinates. Experimental results - the particle motion trajectory and the velocities of the plankton species Epishura baicalensis - obtained using these procedures are presented. To take into account plankton species rotation, additional points of its holographic image, coinciding with the characteristic details of the plankton species, are used. The application of this procedure is also illustrated by experimental results.