图片数据划分训练集、验证集、测试集(包含对应txt的划分，适用目标检测、目标分类)

import os
import random
import shutil

path = "G:/BaiduNetdiskDownload/FallDown/JPEGImages"                                    #要分类的img文件夹
save_path = "G:/BaiduNetdiskDownload/FallDown/fallperson/images/val"                   #划分好的val文件保存路径
path1 = "G:/BaiduNetdiskDownload/FallDown/label"                                        #要分类的txt文件夹
save_path1 = "G:/BaiduNetdiskDownload/FallDown/fallperson/labels/val"                   #划分好的val文件保存路径

if not os.path.exists(save_path):
    os.makedirs(save_path)

img_files = []
for root, dirs, files in os.walk(path):
    for file in files:
        if file.endswith(('.jpg', '.JPG', '.png', '.PNG', '.jpeg', '.JPEG')):
            img_files.append(os.path.join(root, file))

num = range(len(img_files))
n   = int(len(img_files) * 0.2) #划分比例

print(f'num: {len(img_files)}, sample num: {n}')

indexes = random.sample(num, n)

for index in indexes:
    img_file = img_files[index]
    txt_file = os.path.splitext(img_file)[0] + ".txt"
    file_name = os.path.basename(txt_file)
    txt = os.path.join(path1,file_name)
    shutil.move(img_file, save_path)
    shutil.move(txt, save_path1)