schema.md

# Scene2Wave packaged release schema

The Hub release stores each formal sample as one uncompressed tar. The complete
unpacked field reference is retained in `metadata/raw_dataset_schema.md`; the
machine-readable JSON Schema is `metadata/json_schema.json`.

## Archive index

Each line of `metadata/samples.jsonl` contains the original public sample index
fields plus:

- `archive_path`: repository-relative tar path;
- `archive_bytes`: exact archive size;
- `archive_sha256`: lowercase SHA-256 digest.

`relative_path` preserves the original unpacked sample location for provenance.
Use `archive_path` when reading this packaged release.

## Archive member root

Each tar contains:

```text
./sample_metadata.json
./carla/
./sionna/
```

Archive names and checksums are authoritative in `metadata/samples.jsonl` and
`checksums.sha256`. Archives are deterministic: sorted member order, numeric
owner/group zero, and normalized modification time.

## Safe extraction

The release archives are created from project-controlled relative paths. A
generic application should nevertheless reject absolute paths and `..` path
components before extracting any tar obtained from an untrusted source.

Python 3.12 or newer can use `tarfile.extractall(..., filter="data")`. For
earlier Python versions, inspect members before extraction or read files with
`extractfile()` as demonstrated in `README.md`.