===== Edge and Symmetry filter =====
3D Canny-Deriche edge detection filter and symmetry filter.

===== Author =====
Thomas Boudier 

===== Description =====
This plugin will compute the gradients of the image based on the [[https://en.wikipedia.org/wiki/Canny_edge_detector|Canny edge detector]]. 
The symmetry filter will vote for the voxels inside the object based on the gradient vector direction. 

**Alpha parameter** refers to the smoothing in canny edge detection, the smaller the value, the smoother the edges.

{{:plugin:stacks:3d_ij_suite:edgeandsymmetry.png|Edge and symmetry filter}}

The **radius** parameter refer to the radius of the object whose symmetry is to be detected. Normalization and scaling refer to internal values of the algorithm, see Gertych //et al.// for references. The smoothed version is smoothed using ImageJ 3D Gaussian filter with a radius 2. 

The **improved seed detection** refer to a modified implementation to better detect seeds inside objects rather than objects themselves. 

{{:plugin:stacks:3d_ij_suite:edgesymmetry.png|edge and symmetry}}

The gradient vector is perpendicular to the edges, voxels along the direction of the gradient are highlighted and //vote// for the symmetry. 

===== Download =====
For details go to the [[plugin:stacks:3d_ij_suite:start|3D ImageJ Suite]].

===== Citation =====
When using the plugin for publication, please refer to :

J. Ollion, J. Cochennec, F. Loll, C. Escudé, T. Boudier. (**2013**) TANGO: A Generic Tool for High-throughput 3D Image Analysis for Studying Nuclear Organization. //Bioinformatics// 2013 Jul 15;29(14):1840-1. [[http://dx.doi.org/10.1093/bioinformatics/btt276|doi]]

A. Gertych //et al.//, //Computers in Biology and Medecine//, 2015 ([[http://dx.doi.org/10.1016/j.compbiomed.2015.04.025|doi]])

===== License =====
GPL distribution (see [[http://www.cecill.info/index.en.html|licence]] ). Sources for plugins are available freely. Sources for core are available on request.