import cv2
import numpy as np


def watermark(src_path, mask_path, alpha=1):
    # 读取原图
    img = src_path
    # 获取原图高和宽度
    h, w = img.shape[0], img.shape[1]
    # 读取LOG
    mask = mask_path
    if w > h:
            rate = int(w * 0.1) / mask.shape[1]
    else:
            rate = int(h * 0.1) / mask.shape[0]
    mask = cv2.resize(mask, None, fx=rate, fy=rate, interpolation=cv2.INTER_NEAREST)
    mask_h, mask_w = mask.shape[0], mask.shape[1]
    mask_channels = cv2.split(mask)
    dst_channels = cv2.split(img)
    b, g, r, a = cv2.split(mask)

    # 计算mask在图片的坐标
    ul_points = (int(h * 0.9), int(int(w / 2) - mask_w / 2))
    dr_points = (int(h * 0.9) + mask_h, int(int(w / 2) + mask_w / 2))
    for i in range(3):
        dst_channels[i][ul_points[0]: dr_points[0], ul_points[1]: dr_points[1]] = dst_channels[i][
                                                                                  ul_points[0]: dr_points[0],
                                                                                  ul_points[1]: dr_points[1]] * (
                                                                                              255.0 - a * alpha) / 255
        dst_channels[i][ul_points[0]: dr_points[0], ul_points[1]: dr_points[1]] += np.array(
            mask_channels[i] * (a * alpha / 255), dtype=np.uint8)
    dst_img = cv2.merge(dst_channels)
    # cv2.imwrite(r'd:\1_1.jpg', dst_img)
    return dst_img

import time
# 导入我们将要使用的logo
logo = "logo.png"
img2 = "a.jpg"
time11 = time.time()
a = watermark(img2, logo)
time12 = time.time()
print(time12-time11)
cv2.imshow("Watermarked Image", a)
cv2.imwrite("watermarked.jpg", a)
cv2.waitKey(100000)