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digitale-bildverarbeitung-l…/CV-App/algorithms/canny_edges.py

40 lines
1.2 KiB
Python

import cv2
import numpy as np
from . import Algorithm
class CannyEdgeDetector(Algorithm):
""" Converts a BGR image to grayscale"""
def __init__(self):
self.image_count = 0
self.background = None
self.background_update_rate = 0.2
self.threshold = 15
def process(self, img):
img_gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
h, w = img_gray.shape
resized_image = cv2.resize(img_gray, (int(w/2), int(h/2)), interpolation=cv2.INTER_NEAREST)
blurred_img = cv2.GaussianBlur(resized_image, (15, 15), 0)
if self.background is None:
self.background = blurred_img
self.background = (1 - self.background_update_rate) * self.background + self.background_update_rate * blurred_img
diff = blurred_img - self.background
diff_abs = np.abs(diff)
binary_image = diff_abs > self.threshold
canny_edges = canny(resized_image, 50, 100)
canny_edges = canny_edges * binary_image
canny_edges = cv2.resize(canny_edges, (int(w), int(h)), interpolation=cv2.INTER_NEAREST)
return canny_edges
def canny(img, thresh1, thresh2):
img = cv2.Canny(img, thresh1, thresh2)
return img