import numpy as np
import cv2
'''
opencv-python:透明背景图和纯白背景图互转
'''
# 修改透明背景为白色背景图
def transparent2white(img):
height, width, channel = img.shape
for h in range(height):
for w in range(width):
color = img[h, w]
if (color == np.array([0, 0, 0, 0])).all():
img[h, w] = [255, 255, 255, 255]
return img
# 修改纯白背景图为透明背景图
def white2transparent(img):
height, width, channel = img.shape
for h in range(height):
for w in range(width):
color = img[h, w]
if (color == np.array([255, 255, 255, 255])).all():
img[h, w] = [0, 0, 0, 0]
return img
if __name__ == '__main__':
transparent_path = r'transparent.png'
# 一:透明背景图转白背景图
transparent_img = cv2.imread(transparent_path, -1)
# print(transparent_img.shape) #(796, 796, 4)
white_img = transparent2white(transparent_img)
cv2.imwrite('white.jpg', white_img)
# 二:白背景图转透明背景图
white_img = cv2.imread('white.jpg')
# print(white_img.shape) # (796, 796, 3)
white_img = cv2.cvtColor(white_img, cv2.COLOR_BGR2BGRA) # 转为4通道
# print(white_img.shape) # (796, 796, 4)
new_transparent = white2transparent(white_img)
cv2.imwrite('new_transparent.png', new_transparent)