图像标签格式转换

在做图像检测的时候，不同打标签软件得到的标签格式可能会不一样，此处提供lableimg（txt格式）和lableme（json格式）的互换。

json →txt

import os
import json
import cv2
import base64
import argparse


def parse_opt():
    parser = argparse.ArgumentParser()
    # 根据你的路径进行修改
    parser.add_argument('--img_path', type=str, default='img/')
    parser.add_argument('--txt_path', type=str, default='labels/test.txt')
    parser.add_argument('--json_path', type=str, default='json/')
    parser.add_argument('--class_names', type=str, default='[your class name]') # 修改为你的类别名称
    opt = parser.parse_args()
    return opt


def decode_txt_file(txt_path, img_path, json_path, class_names):
    class_name = {i: name for i, name in enumerate(class_names)}
    dic = {}
    dic['version'] = '5.0.2'
    dic['flags'] = {}
    dic['shapes'] = []

    img_name = os.path.basename(txt_path).replace('.txt', '.jpg')
    img = cv2.imread(os.path.join(img_path, img_name))
    imageHeight, imageWidth, _ = img.shape

    with open(txt_path) as f:
        datas = f.readlines()
        for data in datas:
            shape = {}
            data = data.strip().split(' ')
            class_id = int(data[0])
            shape['label'] = class_name[class_id]

            x = float(data[1]) * imageWidth
            y = float(data[2]) * imageHeight
            w = float(data[3]) * imageWidth
            h = float(data[4]) * imageHeight
            x1 = x - w / 2
            y1 = y - h / 2
            x2 = x1 + w
            y2 = y1 + h

            shape['points'] = [[x1, y1], [x2, y2]]
            shape['shape_type'] = 'rectangle'
            shape['flags'] = {}
            dic['shapes'].append(shape)

    dic['imagePath'] = img_name
    dic['imageData'] = base64.b64encode(
        open(os.path.join(img_path, img_name), 'rb').read()).decode('utf-8')
    dic['imageHeight'] = imageHeight
    dic['imageWidth'] = imageWidth
    json_file = os.path.join(json_path, os.path.basename(txt_path).replace('.txt', '.json'))
    with open(json_file, 'w') as fw:
        json.dump(dic, fw)
    print(f'Saved {json_file}.')


if __name__ == '__main__':
    opt = parse_opt()

    img_path = opt.img_path
    txt_path = opt.txt_path
    json_path = opt.json_path
    class_names = opt.class_names.split(',')

    if txt_path.endswith('.txt'):  # 单个文件转换
        decode_txt_file(txt_path, img_path, json_path, class_names)
        print('The conversion of single txt to json is complete')
    else:
        txt_names = os.listdir(txt_path)  # 多个文件转换
        for txt_name in txt_names:
            txt_file = os.path.join(txt_path, txt_name)
            decode_txt_file(txt_file, img_path, json_path, class_names)
        print('The conversion of txt to json is complete')

txt → json

import os
import json
import cv2
import base64
import argparse

def parse_opt():
    # Parse command line arguments.
    parser = argparse.ArgumentParser()
    parser.add_argument('--img_path', type=str, default='img/')
    parser.add_argument('--txt_path', type=str, default='labels')
    parser.add_argument('--json_path', type=str, default='json/')
    parser.add_argument('--class_names', type=str, default='[your class name]') # 修改为你的类别名称
    opt = parser.parse_args()
    return opt


def decode_txt_file(txt_path, img_path, json_path, class_names):
    # Convert a txt file to a json file.
    class_name = {i: name for i, name in enumerate(class_names)}
    dic = {}
    dic['version'] = '5.0.2'
    dic['flags'] = {}
    dic['shapes'] = []

    img_name = os.path.basename(txt_path).replace('.txt', '.jpg')
    img = cv2.imread(os.path.join(img_path, img_name))
    imageHeight, imageWidth, _ = img.shape

    with open(txt_path) as f:
        datas = f.readlines()
        for data in datas:
            shape = {}
            data = data.strip().split(' ')
            class_id = int(data[0])
            shape['label'] = class_name[class_id]

            x = float(data[1]) * imageWidth
            y = float(data[2]) * imageHeight
            w = float(data[3]) * imageWidth
            h = float(data[4]) * imageHeight
            x1 = x - w / 2
            y1 = y - h / 2
            x2 = x1 + w
            y2 = y1 + h

            shape['points'] = [[x1, y1], [x2, y2]]
            shape['shape_type'] = 'rectangle'
            shape['flags'] = {}
            dic['shapes'].append(shape)

    dic['imagePath'] = img_name
    dic['imageData'] = base64.b64encode(
        open(os.path.join(img_path, img_name), 'rb').read()).decode('utf-8')
    dic['imageHeight'] = imageHeight
    dic['imageWidth'] = imageWidth
    json_file = os.path.join(json_path, os.path.basename(txt_path).replace('.txt', '.json'))
    with open(json_file, 'w') as fw:
        json.dump(dic, fw)
    print(f'Saved {json_file}.')


def convert(img_size, box):
    # Convert absolute coordinates to relative coordinates.
    dw = 1. / (img_size[0])
    dh = 1. / (img_size[1])
    x = (box[0] + box[2]) / 2.0 - 1
    y = (box[1] + box[3]) / 2.0 - 1
    w = box[2] - box[0]
    h = box[3] - box[1]
    x = x * dw
    w = w * dw
    y = y * dh
    h = h * dh
    return (x, y, w, h)


def decode_json(json_path, json_name, txt_path):
    # Convert a json file to a txt file.
    class_name = {name: i for i, name in enumerate(class_names)}
    txt_file = open(os.path.join(txt_path, json_name[0:-5] + '.txt'), 'w')
    json_path = os.path.join(json_path, json_name)
    data = json.load(open(json_path, 'r', encoding='gb2312', errors='ignore'))
    img_w = data['imageWidth']
    img_h = data['imageHeight']
    for i in data['shapes']:
        label_name = i['label']
        if (i['shape_type'] == 'rectangle'):
            x1 = int(i['points'][0][0])
            y1 = int(i['points'][0][1])
            x2 = int(i['points'][1][0])
            y2 = int(i['points'][1][1])
            bb = (x1, y1, x2, y2)
            bbox = convert((img_w, img_h), bb)
            txt_file.write(str(class_name[label_name]) + " " + " ".join([str(a) for a in bbox]) + '\n')
    print(f"Saved{json_name[0:-5] + '.txt'}")
    txt_file.close()

if __name__ == '__main__':
    opt = parse_opt()

    img_path = opt.img_path
    txt_path = opt.txt_path
    json_path = opt.json_path
    class_names = opt.class_names.split(',')
    # Convert txt files to json files.
    if txt_path.endswith('.txt'):
        decode_txt_file(txt_path, img_path, json_path, class_names)
        print('The conversion of single txt to json is complete')
    else:
        txt_names = os.listdir(txt_path)
        for txt_name in txt_names:
            txt_file = os.path.join(txt_path, txt_name)
            decode_txt_file(txt_file, img_path, json_path, class_names)
        print('The conversion of txt to json is complete')