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scripts/download_canopy.py

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+#!/usr/bin/env python3
+"""Download ETH Global Canopy Height 2020 tiles for a bounding box."""
+
+from __future__ import annotations
+
+import argparse
+import math
+import sys
+from pathlib import Path
+
+import httpx
+
+# Public tile base used by the ETH Global Canopy Height dataset portal.
+CANOPY_BASE_URL = "https://storage.googleapis.com/earthenginepartners-hansen/GCH2020"
+
+
+def tile_names_for_bbox(min_lat: float, min_lng: float, max_lat: float, max_lng: float) -> list[str]:
+  tiles: list[str] = []
+  for lat in range(math.floor(min_lat), math.ceil(max_lat)):
+    for lng in range(math.floor(min_lng), math.ceil(max_lng)):
+      tiles.append(f"GCH2020_E{lng:03d}N{lat:02d}.tif")
+  return tiles
+
+
+def download_tile(tile: str, output_dir: Path) -> None:
+  output_path = output_dir / tile
+  if output_path.exists():
+    print(f"skip {tile}: already exists")
+    return
+
+  url = f"{CANOPY_BASE_URL}/{tile}"
+  print(f"downloading {tile}...")
+  try:
+    with httpx.stream("GET", url, timeout=300.0, follow_redirects=True) as response:
+      response.raise_for_status()
+      with output_path.open("wb") as file:
+        for chunk in response.iter_bytes():
+          file.write(chunk)
+    print(f"saved {output_path}")
+  except httpx.HTTPError as exc:
+    print(f"failed {tile}: {exc}", file=sys.stderr)
+
+
+def main() -> int:
+  parser = argparse.ArgumentParser(description="Download ETH Global Canopy Height tiles")
+  parser.add_argument("--bbox", nargs=4, type=float, metavar=("MIN_LAT", "MIN_LNG", "MAX_LAT", "MAX_LNG"))
+  parser.add_argument("--tiles", nargs="*", help="Explicit tile filenames")
+  parser.add_argument("--output", default="data/canopy", help="Output directory")
+  args = parser.parse_args()
+
+  output_dir = Path(args.output)
+  output_dir.mkdir(parents=True, exist_ok=True)
+
+  if args.tiles:
+    tiles = args.tiles
+  elif args.bbox:
+    tiles = tile_names_for_bbox(*args.bbox)
+  else:
+    parser.error("provide --bbox or --tiles")
+
+  for tile in tiles:
+    download_tile(tile, output_dir)
+
+  return 0
+
+
+if __name__ == "__main__":
+  raise SystemExit(main())