Zstd Codec

The Zstd codec wraps the standard Zstandard algorithm, allowing the container to use it as a generic meta-compressor.

Theory

Zstandard provides excellent generic compression. In PTWM, it is primarily used as a fallback or forced via the Method::ZSTD selection.

Because the upstream byte-split preprocessing ops already perform the SHUFFLE-style reordering that Zstandard would typically need, the plane codec simply runs plain Zstd over the preprocessed data. PTWM uses a default compression level of 3, which offers a strong balance between speed and ratio.

Usage

This codec accepts any plane descriptor.

References

• Yann Collet, Zstandard. RFC 8878. Link