Region Growing (2D/3D grayscale)

A recursive region growing algorithm for 2D and 3D grayscale image sets with polygon and binary mask output. The main purpose of this function lies on clean and highly documented code.

Usage:
[P, J] = regionGrowing(cIM, initPos, thresVal, maxDist, tfMean, tfFillHoles, tfSimplify)

Inputs:
- cIM: 2D/3D grayscale matrix
- initPos: Coordinates for initial seed position
- thresVal: Absolute threshold level to be included
- maxDist: Maximum distance to the initial position in [px]
- tfMean: Updates the initial value to the region mean (slow)
- tfFillHoles: Fills enclosed holes in the binary mask
- tfSimplify: Reduces the number of vertices with line simplification

Outputs:
- P: VxN array (with V number of vertices, N number of dimensions). P is the enclosing polygon for all associated pixel/voxel
- J: Binary mask (with the same size as the input image) indicating 1 (true) for associated pixel/voxel and 0 (false) for being outside