ROI.py

"""
图像处理：ROI分割
"""

import cv2
import numpy as np


class ROI:
    "从图像中截取感兴趣区域，使用归一化坐标和长宽进行定义，得到具体坐标和长宽"

    def __init__(
        self,
        image: np.ndarray,  # 图像
        x1: float,  # 归一化坐上坐标
        y1: float,
        width: float,  # 长宽
        height: float,
        ifExist=True,
    ):  # 是否暂存图像数据
        "ROI类的实例化，使用归一化的左上点横纵坐标和归一化的长宽"
        imageHeight = image.shape[0]
        imageWidth = image.shape[1]
        self.width = int(width * imageWidth)
        self.height = int(height * imageHeight)
        self.x1 = int(x1 * imageWidth)
        self.y1 = int(y1 * imageHeight)
        if ifExist:
            self.ROI = image[
                self.y1 : (self.y1 + self.height),
                self.x1 : (self.x1 + self.width),
            ].copy()

    def draw(self, image: np.ndarray, color=(180, 0, 0), width=3):
        "将ROI区域在图片上绘制出来"
        cv2.rectangle(
            image,
            (self.x1, self.y1),
            (self.x1 + self.width, self.y1 + self.height),
            color,
            width,
        )

    def isInside(self, point):
        "判断point点是否位于ROI区域内"
        x, y = point
        if (x < self.x1 or x > self.x1 + self.width) or (
            y < self.y1 or y > self.y1 + self.height
        ):
            return False
        else:
            return True

    def getRatio(self, *, isNone=False):
        "返回ROI内某一白色或者黑色像素的占比，isNone是否取反"
        num = cv2.countNonZero(self.ROI)
        ratio = num / (self.height * self.width)
        if isNone:
            return 1 - ratio
        else:
            return ratio