training/convert_coco_categories.py

"""
Optional helper.

Your COCO exporter should already contain the same categories in train and val.
This script prints the category IDs/names so you can compare them with classes.txt.

Usage:
    python training/convert_coco_categories.py data/train/annotations.json
"""

import json
import sys

if len(sys.argv) != 2:
    raise SystemExit("Usage: python training/convert_coco_categories.py annotations.json")

data = json.load(open(sys.argv[1], "r", encoding="utf-8"))
for cat in sorted(data["categories"], key=lambda x: x["id"]):
    print(f'{cat["id"]}: {cat["name"]}')