26 lines
813 B
Python
26 lines
813 B
Python
import cv2
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import numpy as np
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def detect_large_coherent_structures(image: np.ndarray):
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"""Detects large coherent structures on an image.
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Expects an image with binary color space (e.g. threshold applied).
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Returns:
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contours
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References:
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https://stackoverflow.com/questions/60259169/how-to-group-nearby-contours-in-opencv-python-zebra-crossing-detection
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"""
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assert len(image.shape) == 2
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dilate_kernel = cv2.getStructuringElement(cv2.MORPH_OPEN, (5, 5))
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dilate = cv2.dilate(image, dilate_kernel, iterations=4)
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close_kernel = cv2.getStructuringElement(cv2.MORPH_RECT, (20, 20))
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close = cv2.morphologyEx(dilate, cv2.MORPH_CLOSE, close_kernel, iterations=1)
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cnts, _ = cv2.findContours(close, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
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return cnts
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