import cv2
import numpy as np


def get_contour_colors(num_contours):
    # 定义颜色表 (BGR 格式)
    colors = [
        (255, 0, 0),
        (255, 50, 0),
        (255, 100, 0),
        (255, 150, 0),
        (255, 200, 0),
        (255, 255, 0),
        (200, 255, 0),
        (150, 255, 0),
        (100, 255, 0),
        (50, 255, 0),
        (0, 255, 0),
        (0, 255, 50),
        (0, 255, 100),
        (0, 255, 150),
        (0, 255, 200),
        (0, 255, 255),
        (0, 200, 255),
        (0, 150, 255),
        (0, 100, 255),
        (0, 50, 255),
        (0, 0, 255),
    ]
    # 返回一个颜色表
    return [colors[i % len(colors)] for i in range(num_contours)]


def fill_contours(img, contours):
    # 创建空白的图像，用来画轮廓表
    filled_img = np.zeros_like(img)
    num_contours = len(contours)
    # 颜色表
    colors = get_contour_colors(num_contours)

    for i, contour in enumerate(contours):
        cv2.drawContours(filled_img, [contour], -1, colors[i], -1)

    return filled_img


# 读取原图，原图是RGB图
img = cv2.imread('1.png')
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

# 查找轮廓
contours, _ = cv2.findContours(gray, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)

# 填充轮廓
filled_img = fill_contours(img, contours)


cv2.imshow('Filled Contours', filled_img)
cv2.waitKey(0)
cv2.destroyAllWindows()

原图：

输出：