使用Labelme标注软件会生成json格式的文件，而YOLOv5需要的标注文件是txt格式的。使用以下python代码可以使json格式转为txt格式，有几处代码需要修改：

1、json存放的文件夹路径与txt存放的文件夹路径

2、标注过程中用到的标签，以及确认是否使用矩形框进行的标注

3、如果有多个label需要创建if语句，并修改txt_file.write代码

import json
import osdef convert(img_size, box):dw = 1. / (img_size[0])dh = 1. / (img_size[1])x = (box[0] + box[2]) / 2.0 - 1y = (box[1] + box[3]) / 2.0 - 1w = box[2] - box[0]h = box[3] - box[1]x = x * dww = w * dwy = y * dhh = h * dhx1 = box[0]y1 = box[1]x2 = box[2]y2 = box[3]return x, y, w, hdef decode_json(json_folder_path, json_name):txt_name = '/home/xue/xlc/yolov5/' + json_name[0:-5] + '.txt'  # 生成的txt文件存放的路径txt_file = open(txt_name, 'w')json_path = os.path.join(json_folder_path, json_name)data = json.load(open(json_path, 'r', encoding='utf-8'))img_w = data['imageWidth']img_h = data['imageHeight']for i in data['shapes']:if i['shape_type'] == 'rectangle' and i['label'] == 'person':  # 分类的标签x1 = float((i['points'][0][0]))y1 = float((i['points'][0][1]))x2 = float((i['points'][1][0]))y2 = float((i['points'][1][1]))bb = (x1, y1, x2, y2)bbox = convert((img_w, img_h), bb)txt_file.write('0' + " " + " ".join([str(a) for a in bbox]) + '\n')if __name__ == "__main__":json_folder_path = '/home/xue/xlc/yolov5/ImageData/'  # json文件存放的路径json_names = os.listdir(json_folder_path)for json_name in json_names:decode_json(json_folder_path, json_name)