Object feature extraction

Dragonfly is a software platform for the intuitive inspection of multi-scale multi-modality image data. Its user-friendly experience translates into powerful quantitative findings with high-impact visuals, driven by nuanced easy-to-learn controls.

For segmentation: It provides an engine fior machine Learning, Watershed and superpixel methods, support histological data .

It offers a 3D viewer, and python scripting capacities .

It is free for reserach use, but not for commercial usage.

The research goal of this paper was to provide unbiased counts of labeled astrocytes and to estimate the area they cover, further to develop tools for defining the orientation of coupling within astrocyte networks under different stimuli.

In order to count the astrocytes and estimate the area they cover the following steps were used in this software.

Pre-processing: z-project (using max intensity); split channels; subtract background; remove outliers.

Segmentation: adjust threshold and convert to a binary file; Watershed.

Cell counting: Analyze particles

Measure Astrocytic network area: select a ROI using the polygon tool; set measurements (area); ROI manager -> add the traced polygon; measure.

This suite provides plugins to enhance 3D capabilities of ImageJ.

• 3D Filters (mean, median, max, min, tophat, max local, …) and edge and symmetry filter
• 3D Segmentation (iterative thresholding, spots segmentation, watershed, …)
  • 3D hysteresis thresholding with two thresholds (see 2D hysteresis for explanation).
  • 3D simple segmentation with thresholding to label 3D objects (similar to 3D objects counter).
  • 3D iterative thresholding (find optimal threshold for each object).
  • 3D spot segmentation with various local threshold estimations.
  • 3D Maxima Finder (with noise parameter)
  • 3D seeds-based watershed with automatic local maxima detection for seeds.
• 3D Mathematical Morphology tools (fill holes, binary closing, distance map, …)
• 3D RoiManager (3D display and analysis of 3D objects)
• 3D Analysis (Geometrical measurements, Mesh measurements, Convex hull, …)
  • 3D Geometrical measurements (volume, surface, …) for each labelled object.
  • 3D Centroid, to compute centroids of labelled objects.
  • 3D Intensity measurements (mean, integrated density, …) in a opened image for each labelled object.
  • 3D Shape measurements (compactness, elongation, …) for each labelled object.
  • 3D Mesh Measurements after triangulation (see 3D Viewer for surface mesh computation).
  • 3D fitting by an ellipsoid and main direction computation (details here).
  • 3D convex hull (see http://rsbweb.nih.gov/ij/plugins/3d-convex-hull/index.html).
  • 3D Radial Distance Area Ratio (RDAR)
  • 3D Density, to compute density of dots, based on closest distance analysis (details here).
• 3D MereoTopology (Relationship between objects)
• 3D Tools (Drawing ellipsoids and lines, cropping, …)
  • Drawing 3D line
  • Drawing 3D ellipsoids in any direction
  • Drawing in stacks as volumes
  • Drawing in 3D viewer as surfaces

There are many methods in bio-imaging that can be parametrized. This gives more flexibility
to the user as long as tools provide easy support for tuning parameters. On the other hand, the
datasets of interest constantly grow which creates the need to process them in bulk. Again,
this requires proper tool support, if biologist is going to be able to organize such bulk
processing in an ad-hoc manner without the help of a programmer. Finally, new image
analysis algorithms are being constantly created and updated. Yet, lots of work is necessary to
extend a prototype implementation into product for the users. Therefore, there is a growing
need for software with a graphical user interface (GUI) that makes the process of image
analysis easier to perform and at the same time allows for high throughput analysis of raw
data using batch processing and novel algorithms. Main program in this area are written in
Java, but Python grow in bioinformatics and will be nice to allow easy wrap algorithm written
in this language.
Here we present PartSeg, a comprehensive software package implementing several image
processing algorithms that can be used for analysis of microscopic 3D images. Its user
interface has been crafted to speed up workflow of processing datasets in bulk and to allow
for easy modification of algorithm’s parameters. In PartSeg we also include the first public
implementation of Multi-scale Opening algorithm descibed in [1]. PartSeg allows for
segmentation in 3D based on finding connected components. The segmentation results can be
corrected manually to adjust for high noise in the data. Then, it is possible to calculate some
standard statistics like volume, mass, diameter and their user-defined combinations for the
results of the segmentation. Finally, it is possible to superimpose segmented structures using
weighted PCA method. Conclusions: PartSeg is a comprehensive and flexible software
dedicated to help biologists in processing, segmentation, visualization and the analysis of the
large microscopic 3D image data. PartSeg provides well established algorithms in an easy-touse,
intuitive, user-friendly toolbox without sacrificing their power and flexibility.

Examples include Chromosome territory analysis.