Seth
Published

Gaussian Distribution?

Hello... did you ever want to set up a gaussian distribution on your BeagleBoard. org family of boards, e.g. the BBAI?

BeginnerProtip1 hour2,822
Gaussian Distribution?

Things used in this project

Hardware components

BeagleBone AI
BeagleBoard.org BeagleBone AI
×1
Fan 5v
×1
USB 3.0 Hub
×1
keyboard (USB)
×1
mouse (USB)
×1
Micro HDMI Cable to HDMI Cable
×1

Software apps and online services

Debian

Story

Read more

Schematics

BeagleBoard.org Came Out w/ a New Board

Here it is!

Code

Bell Curve (Circles)?

Python
This is it!
#!/usr/bin/env python

# Python 2/3 compatibility
from __future__ import print_function
import sys
PY3 = sys.version_info[0] == 3

if PY3:
    xrange = range

import numpy as np
from numpy import random
import cv2

def make_gaussians(cluster_n, img_size):
    points = []
    ref_distrs = []
    for i in xrange(cluster_n):
        mean = (0.1 + 0.8*random.rand(2)) * img_size
        a = (random.rand(2, 2)-0.5)*img_size*0.1
        cov = np.dot(a.T, a) + img_size*0.05*np.eye(2)
        n = 100 + random.randint(900)
        pts = random.multivariate_normal(mean, cov, n)
        points.append( pts )
        ref_distrs.append( (mean, cov) )
    points = np.float32( np.vstack(points) )
    return points, ref_distrs

def draw_gaussain(img, mean, cov, color):
    x, y = np.int32(mean)
    w, u, vt = cv2.SVDecomp(cov)
    ang = np.arctan2(u[1, 0], u[0, 0])*(180/np.pi)
    s1, s2 = np.sqrt(w)*3.0
    cv2.ellipse(img, (x, y), (s1, s2), ang, 0, 360, color, 1, cv2.LINE_AA)


if __name__ == '__main__':
    cluster_n = 5
    img_size = 512

    print('press any key to update distributions, ESC - exit\n')

    while True:
        print('sampling distributions...')
        points, ref_distrs = make_gaussians(cluster_n, img_size)

        print('EM (opencv) ...')
        em = cv2.ml.EM_create()
        em.setClustersNumber(cluster_n)
        em.setCovarianceMatrixType(cv2.ml.EM_COV_MAT_GENERIC)
        em.trainEM(points)
        means = em.getMeans()
        covs = em.getCovs()  # Known bug: https://github.com/opencv/opencv/pull/4232
        found_distrs = zip(means, covs)
        print('ready!\n')
		
		img = np.zeros((img_size, img_size, 3), np.uint8)
        for x, y in np.int32(points):
            cv2.circle(img, (x, y), 1, (255, 255, 255), -1)
        for m, cov in ref_distrs:
            draw_gaussain(img, m, cov, (0, 255, 0))
        for m, cov in found_distrs:
            draw_gaussain(img, m, cov, (0, 0, 255))

        cv2.imshow('gaussian mixture', img)
        ch = cv2.waitKey(0)
        if ch == 27:
            break
    cv2.destroyAllWindows()

Credits

Seth

Seth

32 projects • 12 followers
Stay there and someone will find you...
Thanks to Beagleboard.org people for Producing the AI, OpenCV developers, and Unknown for now.

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