coco的json label转换为VOC的xml格式

import os
import json
import cv2
from lxml import etree
import xml.etree.cElementTree as ET
import time
import pandas as pd
from tqdm import tqdm



anno = "annotations_without_background.json"
xml_dir = "anno_xml/"

#Create anno dir
dttm = time.strftime("%Y%m%d%H%M%S", time.localtime())
if os.path.exists(xml_dir):
    os.rename(xml_dir,xml_dir+dttm)
os.mkdir(xml_dir)
# Read json file


import json
with open(anno,'r') as load_f:
    f = json.load(load_f)

imgs = f['images']

df_cate = pd.DataFrame(f['categories'])
df_cate_sort = df_cate.sort_values(["id"],ascending=True)
categories = list(df_cate_sort['name'])
df_anno = pd.DataFrame(f['annotations'])


#anno_list = list(annos.itertuples(index=False))
#print(anno_list[0]['id'])



for i in tqdm(range(len(imgs))):
    xml_content = []
    file_name = imgs[i]['file_name']
    height = imgs[i]['height']
    img_id = imgs[i]['id']
    width = imgs[i]['width']

    xml_content.append("")
    xml_content.append("	VOC2007")
    xml_content.append("	"+file_name+"")
    xml_content.append("	")
    xml_content.append("		"+str(width)+"")
    xml_content.append("		"+str(height)+"")
    xml_content.append("	")
    xml_content.append("	0")
    #通过img_id找到annotations
    annos = df_anno[df_anno["image_id"].isin([img_id])]

    for index, row in annos.iterrows():
        bbox = row["bbox"]
        category_id = row["category_id"]
        cate_name = categories[category_id]

        # add new object
        xml_content.append("	")
    xml_content.append("")

    x = xml_content
    xml_content=[x[i] for i in range(0,len(x)) if x[i]!="\n"]
    ### list存入文件    
    xml_path = os.path.join(xml_dir,file_name.replace('.jpg','.xml'))
    with open(xml_path, 'w+',encoding="utf8") as f:
        f.write('\n'.join(xml_content))
    xml_content[:]=[]