Calculate Feret diameter.
Project description
Python Module to calculate the Feret Diameter of Binary Images
This python module can calculate the maximum Feret diameter (maxferet) and minimum Feret diameter (minferet) of a binary image. For a detailed explanation see this wikipedia page.
Installation
This project is available with pip
pip install feret
Informations
Maxferet
The maxferet is calculated as the maximum euclidean distance of all pixels.
Minferet
The minferet is only approximated in two steps at the moment. First , the distance of to parallel lines, which surrund the object, are calculated for all angles from 0° to 180°. The minimum of of this first calculation is used as initial guess for a minimization algorithm, which is the second part of the approximation. Even if this method is not perfect, the difference to the true minferet can be neglegted for most cases.
At this early development stage, it can only calculate the maximum and minimum Feret Diameter but feature releases will offer the Feret diameter 90° to maximum and minimum. The module will also not return the angle of the diameters. Many things will come in the future.
Use
The module can be used as followed:
import feret
import tifffile as tif
img = tif.imread('example.tif')
# get the class
res = feret.calc(img)
maxf, minf = res.maxferet, res.minferet
# get the values
maxf, minf = feret.all(img)
# get only maxferet
maxf = feret.max(img)
# get only minferet
minf = feret.min(img)
At the moment there is only one option. It is possible to use the pixel corners instead of the pixel centers. ImageJ uses the pixel corners. Here the keyword edge
is used. See the following code to get maxferet und minferet for the edges.
import feret
import tifffile as tif
img = tif.imread('example.tif')
# get the class
res = feret.calc(img, edge=True)
maxf, minf = res.maxferet, res.minferet
# get the values
maxf, minf = feret.all(img, edge=True)
# get only maxferet
maxf = feret.max(img, edge=True)
# get only minferet
minf = feret.min(img, edge=True)
Project details
Release history Release notifications | RSS feed
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.