TITLE:
Occlusion Robust Low-Contrast Sperm Tracking Using Switchable Weight Particle Filtering
AUTHORS:
Mohammadreza Ravanfar, Leila Azinfar, Mohammad Hassan Moradi, Reza Fazel-Rezai
KEYWORDS:
Sperm Tracking, Particle Filtering, Object Occlusion, Watershed Algorithm
JOURNAL NAME:
Advances in Sexual Medicine,
Vol.4 No.3,
July
28,
2014
ABSTRACT:
Sperm motility analysis has a particular place in male fertility diagnosis. Computerized sperm tracking has an important role in extracting sperm trajectory and measuring sperm’s dynamic features. Due to free movements of sperms in three dimensions, occlusion has remained a challenging problem in this area. This paper aims to present a robust single sperm tracking method being able to handle misdetections in sperm occlusion scenes. In this paper, a robust method of segmentation was utilized to provide the required measurements for a switchable weight particle filtering which was designed for single sperm tracking. In each frame, the target sperm was categorized in one of these three stages: before occlusion, occlusion, and after occlusion where the occlusion had been detected based on sperm’s physical characteristics. Depending on the target sperm stage, particles were weighted differently. In order to evaluate the algorithm, two groups of samples were studied where an expert had selected a single sperm of each sample to track manually and automatically. In the first group, the sperms with no occlusion along their trajectories were tracked to depict the general compatibility of the algorithm with sperm tracking. In the second group, the algorithm was applied on the sperms which had at least one occlusion during their path. The algorithm showed an accuracy of 95% on the first group and 86.66% on the second group which illustrate the robustness of the algorithm against occlusion.