python-单通道图像转三通道

'''
单通道->三通道
'''
import os
import cv2
import numpy as np
import PIL.Image as Image
import os
#os.environ['CUDA_VISIBLE_DEVICES'] = '2'
img_path='/home/gyx/QR/qr_detect_model/dataset/images_all_channel_1/'
save_img_path='/home/gyx/QR/qr_detect_model/dataset/images_all_channel_3/'
for img_name in os.listdir(img_path):
    image=Image.open(img_path+img_name)
    if len(image.split())==1: #查看通道数
        print(len(image.split()))
        print(img_path+img_name)
        img = cv2.imread(img_path+img_name)
        gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
        img2 = np.zeros_like(img)
        img2[:,:,0] = gray
        img2[:,:,1] = gray
        img2[:,:,2] = gray
        cv2.imwrite(save_img_path+img_name, img2)
        image=Image.open(save_img_path+img_name)
        print(len(image.split()))
    else:
        image.save(save_img_path+img_name)

'''
单通道->三通道
'''
#img_src = np.expand_dims(img_src, axis=2)
#img_src = np.concatenate((img_src, img_src, img_src), axis=-1)