图片清理去除灰度图时出现程序已被占用问题

最近做深度学习有遇到图像通道数不同而产生输入与预期不符：

expected input（*，*，3）but （*，*，3）

这是因为rgb图像中混杂着灰度图像导致通道数不唯一

本来想着就写个代码把灰度图删掉

import os
from PIL import Image
import numpy as np
contents = ['Abyssinian', 'Bengal', 'Calico', 'Domestic Long Hair', 'Egyptian Mau', 'Havana', 'Himalayan', 'Tabby',
            'Tiger', 'Turkish Van']


def is_gray(img, threshold=10):
    if len(img.getbands()) == 1:
        return True
    img1 = np.asarray(img.getchannel(channel=0), dtype=np.int16)
    img2 = np.asarray(img.getchannel(channel=1), dtype=np.int16)
    img3 = np.asarray(img.getchannel(channel=2), dtype=np.int16)
    diff1 = (img1 - img2).var()
    diff2 = (img2 - img3).var()
    diff3 = (img3 - img1).var()
    diff_sum = (diff1 + diff2 + diff3) / 3.0
    if diff_sum <= threshold:
        return True
    else:
        return False


for content in contents:
    for img_path in os.listdir('./images/' + content):
        #img = open('./images/' + content + '/' + img_path,'rb')
        img = Image.open('./images/' + content + '/' + img_path)

        if is_gray(img):
            
            os.remove('./images/' + content + '/' + img_path)

却又出现新的报错：程序已被占用，最后发现只是打开了图片没有及时关掉而已

更新代码如下：

至此问题解决

import os
from PIL import Image
import numpy as np
contents = ['Abyssinian', 'Bengal', 'Calico', 'Domestic Long Hair', 'Egyptian Mau', 'Havana', 'Himalayan', 'Tabby',
            'Tiger', 'Turkish Van']


def is_gray(img, threshold=10):
    if len(img.getbands()) == 1:
        return True
    img1 = np.asarray(img.getchannel(channel=0), dtype=np.int16)
    img2 = np.asarray(img.getchannel(channel=1), dtype=np.int16)
    img3 = np.asarray(img.getchannel(channel=2), dtype=np.int16)
    diff1 = (img1 - img2).var()
    diff2 = (img2 - img3).var()
    diff3 = (img3 - img1).var()
    diff_sum = (diff1 + diff2 + diff3) / 3.0
    if diff_sum <= threshold:
        return True
    else:
        return False


for content in contents:
    for img_path in os.listdir('./images/' + content):
        #img = open('./images/' + content + '/' + img_path,'rb')
        img = Image.open('./images/' + content + '/' + img_path)

        if is_gray(img):
            img.close()
            os.remove('./images/' + content + '/' + img_path)