Extract tiles in a PMTiles file to a directory in z/x/y.ext format. Chat GPT wrote this for me.

extract-pmtiles.py

#!/usr/bin/env python3
import argparse
import os

from pmtiles.reader import all_tiles
from pmtiles.reader import MmapSource
from pmtiles.reader import Reader
from pmtiles.tile import TileType
from tqdm import tqdm


def get_file_extension(tile_type: TileType) -> str:
    extensions = {
        TileType.UNKNOWN: "unknown",
        TileType.MVT: "mvt",
        TileType.PNG: "png",
        TileType.JPEG: "jpg",
        TileType.WEBP: "webp",
        TileType.AVIF: "avif",
    }
    return extensions.get(tile_type, "unknown")


def extract_tiles(pmtiles_file: str, dest_dir: str) -> None:
    if not os.path.exists(pmtiles_file):
        print(f"Error: PMTiles file '{pmtiles_file}' does not exist.")
        exit(1)

    if not os.path.exists(dest_dir):
        os.makedirs(dest_dir)

    with open(pmtiles_file, "rb") as f:
        source = MmapSource(f)
        reader = Reader(source)
        header = reader.header()
        tile_type = header["tile_type"]

        for zxy, tile_data in tqdm(
            all_tiles(source), "Extracting tiles", unit=" tiles"
        ):
            z, x, y = zxy
            tile_dir = os.path.join(dest_dir, str(z), str(x))
            os.makedirs(tile_dir, exist_ok=True)
            extension = get_file_extension(tile_type)
            tile_path = os.path.join(tile_dir, f"{y}.{extension}")
            with open(tile_path, "wb") as tile_file:
                tile_file.write(tile_data)


def main() -> None:
    parser = argparse.ArgumentParser(description="Extract PMTiles to a directory.")
    parser.add_argument("pmtiles_file", type=str, help="Path to the PMTiles file.")
    parser.add_argument(
        "dest_dir", type=str, help="Destination directory for the extracted tiles."
    )
    args = parser.parse_args()
    extract_tiles(args.pmtiles_file, args.dest_dir)


if __name__ == "__main__":
    main()