import datetime, math, os, sys, logging
import cv2
import numpy as np


def f1(image_path):
    # Load an image
    img = cv2.imread(image_path)
    # img = cv2.imread(image_path, 0)  # Load an image in grayscale

    b, g, r = cv2.split(img)
    cloud = r / b

    ret, cloud_BINARY = cv2.threshold(cloud, 0.6, 255, cv2.THRESH_BINARY)  # 文献中推荐阈值为0.6
    cloudage = cloud_BINARY.sum() / (cloud_BINARY.size * 255)

    print("r/b算法，云量为%f\n" % cloudage)

    tmp = image_path.split('.')
    out = tmp[0] + "_r_b." + tmp[1]
    cv2.imwrite(out, cloud_BINARY)

    # cv2.imshow('image', cloud_BINARY)
    cv2.waitKey(0)
    cv2.destroyAllWindows()


def f2(image_path):
    img = cv2.imread(image_path)

    b, g, r = cv2.split(img)
    cloud = (b-r) / (b+r)

    ret, cloud_BINARY = cv2.threshold(cloud, 0.2, 255, cv2.THRESH_BINARY_INV)
    cloudage = cloud_BINARY.sum() / (cloud_BINARY.size * 255)

    print("(b-r) / (b+r)算法，云量为%f\n" % cloudage)

    tmp = image_path.split('.')
    out = tmp[0] + "_(b-r)_(b+r)." + tmp[1]
    cv2.imwrite(out, cloud_BINARY)

    # cv2.imshow('image', cloud_BINARY)
    cv2.waitKey(0)
    cv2.destroyAllWindows()


def f3(image_path):
    img = cv2.imread(image_path)
    b, g, r = cv2.split(img)

    # # 转到HSV空间
    # hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
    # h, s, v = cv2.split(hsv)

    # 转到HLS空间
    hls = cv2.cvtColor(img, cv2.COLOR_BGR2HLS)  # 这就是ihs颜色空间：
    h, l, s = cv2.split(hls)

    μ_Clouds = 12.7
    σ_Clouds = 3.7

    μ_sky = 45.3
    σ_sky = 4.4

    # np.where用法：https://www.zhihu.com/question/62844162
    clouds_loc = np.where(s < μ_Clouds + 3 * σ_Clouds)  # 厚云
    sky_loc = np.where(s > μ_sky - 3 * σ_sky)  # 天空
    unknow_loc = np.where((μ_Clouds + 3 * σ_Clouds <= s) & (s <= μ_sky - 3 * σ_sky))  # 薄云

    s[sky_loc] = 1
    s[clouds_loc] = 2
    s[unknow_loc] = 3

    tmp = image_path.split('.')
    out = tmp[0] + "_saturation." + tmp[1]
    cv2.imwrite(out, s)

    # cv2.imshow('image', cloud_BINARY)
    cv2.waitKey(0)
    cv2.destroyAllWindows()


if __name__ == '__main__':
    image_path = r'D:\PycharmProjects\cloudage\photo\photo7.jpg'
    # image_path = r'D:\PycharmProjects\cloudage\photo\cloud1_perfect.jpg'  # f3全为天空
    f1(image_path)
    f2(image_path)
    f3(image_path)