xml格式转yolo txt格式代码

你可以参考以下代码来进行xml格式到yolo txt格式的转换：

import xml.etree.ElementTree as ET
import os

def convert(size, box):
    dw = 1. / size[0]
    dh = 1. / size[1]
    x = (box[0] + box[1]) / 2.0
    y = (box[2] + box[3]) / 2.0
    w = box[1] - box[0]
    h = box[3] - box[2]
    x = x * dw
    w = w * dw
    y = y * dh
    h = h * dh
    return (x, y, w, h)

def convert_annotation(xml_path, txt_path):
    in_file = open(xml_path)
    out_file = open(txt_path, 'w')
    tree = ET.parse(in_file)
    root = tree.getroot()
    size = root.find('size')
    w = int(size.find('width').text)
    h = int(size.find('height').text)
    for obj in root.iter('object'):
        difficult = obj.find('difficult').text
        cls = obj.find('name').text
        if cls not in classes or int(difficult) == 1:
            continue
        cls_id = classes.index(cls)
        xmlbox = obj.find('bndbox')
        b = (float(xmlbox.find('xmin').text), float(xmlbox.find('xmax').text), float(xmlbox.find('ymin').text), float(xmlbox.find('ymax').text))
        bb = convert((w, h), b)
        out_file.write(str(cls_id) + " " + " ".join([str(a) for a in bb]) + '\n')

xml_folder = '/path/to/xml/folder'
txt_folder = '/path/to/txt/folder'
classes = ['class1', 'class2', 'class3']
for xml_file in os.listdir(xml_folder):
    xml_path = os.path.join(xml_folder, xml_file)
    txt_file = os.path.splitext(xml_file)[0] + '.txt'
    txt_path = os.path.join(txt_folder, txt_file)
    convert_annotation(xml_path, txt_path)

这段代码可以将指定文件夹中的所有xml格式的标注文件转换成yolo txt格式的标注文件，其中classes变量需要根据实际情况修改。