| from __future__ import annotations |
|
|
| from pathlib import Path |
| from PIL import Image, ExifTags |
| import csv |
| import argparse |
|
|
|
|
| def _to_deg(value): |
| """Convert EXIF GPS coordinates to float degrees.""" |
| try: |
| def to_float(x): |
| try: |
| if isinstance(x, tuple) and len(x) == 2: |
| return x[0] / x[1] |
| except Exception: |
| pass |
| return float(x) |
|
|
| d = to_float(value[0]) |
| m = to_float(value[1]) |
| s = to_float(value[2]) |
| return d + (m / 60.0) + (s / 3600.0) |
| except Exception: |
| return None |
|
|
|
|
| def exif_latlon(img_path: Path): |
| """Read (lat, lon) from image EXIF. Returns tuple or None if missing.""" |
| try: |
| with Image.open(img_path) as img: |
| exif = img._getexif() or {} |
| except Exception: |
| return None |
|
|
| if not exif: |
| return None |
|
|
| exif_dict = {ExifTags.TAGS.get(k, k): v for k, v in exif.items()} |
| gps_tag = exif_dict.get('GPSInfo') |
| if not gps_tag: |
| return None |
|
|
| gps = {ExifTags.GPSTAGS.get(k, k): v for k, v in gps_tag.items()} |
| lat_raw = gps.get('GPSLatitude') |
| lon_raw = gps.get('GPSLongitude') |
| if lat_raw is None or lon_raw is None: |
| return None |
|
|
| lat = _to_deg(lat_raw) |
| lon = _to_deg(lon_raw) |
| if lat is None or lon is None: |
| return None |
|
|
| if gps.get('GPSLatitudeRef', 'N') in ('S', b'S'): |
| lat = -lat |
| if gps.get('GPSLongitudeRef', 'E') in ('W', b'W'): |
| lon = -lon |
|
|
| return lat, lon |
|
|
|
|
| def extract_split(split_dir: Path) -> Path: |
| """Scan a split directory for images and write metadata.csv with |
| columns: file_name, Latitude, Longitude (as per notebook). |
| Returns path to the written CSV. |
| """ |
| exts = {'.jpg', '.jpeg', '.JPG', '.JPEG'} |
| rows = [] |
| total = 0 |
|
|
| for p in split_dir.rglob('*'): |
| if p.is_file() and p.suffix in exts: |
| total += 1 |
| ll = exif_latlon(p) |
| if ll: |
| |
| rel = p.relative_to(split_dir) |
| rows.append([str(rel).replace('\\\\', '/'), ll[0], ll[1]]) |
|
|
| out_csv = split_dir / 'metadata.csv' |
| with out_csv.open('w', newline='', encoding='utf-8') as f: |
| w = csv.writer(f) |
| w.writerow(['file_name', 'Latitude', 'Longitude']) |
| w.writerows(rows) |
|
|
| print(f"Split: {split_dir}") |
| print(f"Scanned {total} images; extracted {len(rows)} with GPS.") |
| print(f"Wrote: {out_csv}") |
| return out_csv |
|
|
|
|
| def main(): |
| ap = argparse.ArgumentParser(description='Extract metadata.csv for a split directory (Route B).') |
| ap.add_argument('split_dir', type=Path, help='Path to a split directory (e.g., data/train)') |
| args = ap.parse_args() |
|
|
| if not args.split_dir.exists() or not args.split_dir.is_dir(): |
| raise SystemExit(f"Split directory not found: {args.split_dir}") |
|
|
| extract_split(args.split_dir) |
|
|
|
|
| if __name__ == '__main__': |
| main() |
|
|
|
|
