File: hull_demo.py

package info (click to toggle)
opencv 4.10.0%2Bdfsg-5
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 282,092 kB
  • sloc: cpp: 1,178,079; xml: 682,621; python: 49,092; lisp: 31,150; java: 25,469; ansic: 11,039; javascript: 6,085; sh: 1,214; cs: 601; perl: 494; objc: 210; makefile: 173
file content (57 lines) | stat: -rw-r--r-- 1,703 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
from __future__ import print_function
import cv2 as cv
import numpy as np
import argparse
import random as rng

rng.seed(12345)

def thresh_callback(val):
    threshold = val

    # Detect edges using Canny
    canny_output = cv.Canny(src_gray, threshold, threshold * 2)

    # Find contours
    contours, _ = cv.findContours(canny_output, cv.RETR_TREE, cv.CHAIN_APPROX_SIMPLE)

    # Find the convex hull object for each contour
    hull_list = []
    for i in range(len(contours)):
        hull = cv.convexHull(contours[i])
        hull_list.append(hull)

    # Draw contours + hull results
    drawing = np.zeros((canny_output.shape[0], canny_output.shape[1], 3), dtype=np.uint8)
    for i in range(len(contours)):
        color = (rng.randint(0,256), rng.randint(0,256), rng.randint(0,256))
        cv.drawContours(drawing, contours, i, color)
        cv.drawContours(drawing, hull_list, i, color)

    # Show in a window
    cv.imshow('Contours', drawing)

# Load source image
parser = argparse.ArgumentParser(description='Code for Convex Hull tutorial.')
parser.add_argument('--input', help='Path to input image.', default='stuff.jpg')
args = parser.parse_args()

src = cv.imread(cv.samples.findFile(args.input))
if src is None:
    print('Could not open or find the image:', args.input)
    exit(0)

# Convert image to gray and blur it
src_gray = cv.cvtColor(src, cv.COLOR_BGR2GRAY)
src_gray = cv.blur(src_gray, (3,3))

# Create Window
source_window = 'Source'
cv.namedWindow(source_window)
cv.imshow(source_window, src)
max_thresh = 255
thresh = 100 # initial threshold
cv.createTrackbar('Canny thresh:', source_window, thresh, max_thresh, thresh_callback)
thresh_callback(thresh)

cv.waitKey()