Target detection label format conversion (horizontal frame)

JSON to YOLOV5

import json
import os
import glob
import cv2


def mkdir(path):
    if not os.path.exists(path):
        os.mkdir(path)

def convert(size, box):
    dw = 1. / (size[0])
    dh = 1. / (size[1])
    x = (box[0] + box[1]) / 2.0 - 1
    y = (box[2] + box[3]) / 2.0 - 1
    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 decode_json(json_path, txt_name):
    txt_file = open(txt_name, 'w')
    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'] == 'js'):
            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, x2, y1, y2)
            bbox = convert((img_w, img_h), bb)
            txt_file.write( '0' + " " + " ".join([str(a) for a in bbox]) + '\n')


if __name__ == '__main__':
    mkdir('labels')
    jsonList = glob.glob('images/*.json')
    for jsonPath in jsonList:
        baseName = os.path.basename(jsonPath).split('.')[0]
        txtName = f'labels/{baseName}.txt'
        decode_json(jsonPath, txtName)