what is the algorithm of bwconncomp?

Anyone know the algorithm of bwconncomp? and how do they work to generate a pixel index list output from a binary image?

Answer 1

[Walter Roberson]

https://www.mathworks.com/help/images/ref/bwconncomp.html#bu2xdbl-6

Algorithms

The basic steps in finding the connected components are:

1. Search for the next unlabeled pixel, p.
2. Use a flood-fill algorithm to label all the pixels in the connected component containing p.
3. Repeat steps 1 and 2 until all the pixels are labeled.

[Image Analyst]

Searching starts at the top left pixel and goes down rows in the left-most (first) column, then moves to the next column to the right going down rows looking for unlabeled pixels, and continues until all columns have been checked.

[Walter Roberson]

The documentation no longer has an Algorithms section; the last version this was documented is https://www.mathworks.com/help/releases/R2021b/images/ref/bwconncomp.html#bu2xdbl-6