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Table 1 Image analysis parameters and their mathematical description

From: Dynamic biospeckle analysis, a new tool for the fast screening of plant nematicide selectivity

Term Definition Formula
Speckle Spike in light intensity captured by the camera and created by light interference in a heterogeneous medium  
Biospeckle The dynamic speckle generated by living organisms. Speckle can be created by internal, cellular processes or body movement. Biospeckle data are in the form of 3D volume data, namely a set of voxels Ω with width (w), height (h) and depth (d), resulting from the BSPIM system \(\Omega ={\left\{{X}_{j}\right\}}_{j<w\times h\times d}\)
BSPIM Biospeckle Selective Plane Illumination Microscopy; an imaging method that quantifies the activity of biological organisms within 3D volumes through the analysis of dynamic speckle  
Detected biospeckle object A subset of the volume image data generated by BSPIM. The subset is a connected region detected above background noise. The ith detected object is a subset Ωi Ωi
Biospeckle volume Number of voxels in the ith object \({N}_{i}=n\left({\Omega }_{i}\right)\)
Biospeckle intensity Mean of grey values Xj of the ith detected biospeckle object. Specific to each nematode \({I}_{i}=\frac{1}{{N}_{i}}{\sum }_{{X}_{j}\in {\Omega }_{i}}{X}_{j}\)
Total Biospeckle Intensity Sum of mean object intensities. Gives the total biospeckle intensity for the whole sample \(\mu =\sum {I}_{i}\)
Biospeckle pattern Distribution (position and intensity of pixels) of a detected biospeckle object Ωi. Patterns can be described by several parameters such as intensity, area, volume and circularity  
Biospeckle area A set of connected pixels in the 2D plane maximizing the surface area of the detected biospeckle object \(S={A}_{k}\)
Circularity of biospeckle area Circularity of fitted convex hull of surface area S and perimeter P \({C}_{A}=4\pi S/{P}^{2}\)