poka.sh

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LZ4

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LZ4 Frame Preview.

At a glance
Purpose An LZ4-compressed file in the LZ4 frame format (or the legacy format).
Extensions .lz4
Poka parser poka-lz4
Viewer poka-metadata-card-viewer
Depth tier Metadata card (see Depth tiers)
Breadth tier B4 Summary (see Breadth tiers)

How much Poka reads

B4 Summary. The container and metadata are read and summarised (counts, properties, structure), but the main content is not rendered.

Confidence: medium (the reviewer read the code). Basis: Reviewed 2026-10-26: read parsers/poka-lz4/src/main.rs (272 lines) and plugin.json. No unit tests or tests/samples.rs; the corpus has no .lz4 and .lz4-frame sample. Covers .lz4 and .lz4-frame. The card decodes the frame descriptor (version, block independence, block and content checksums, content size, dictionary ID, maximum block size) and walks the blocks (compressed and stored blocks, largest block, payload total, end mark); legacy and skippable frames are named. Judgement: B4: the stream's structure is walked and summarised, but nothing is decompressed.

What Poka does not read

  • The data is not decompressed, so the content is not shown
  • Only the first frame is walked; concatenated frames are not
  • Legacy-format files show only the magic
  • Checksums are not verified
  • Files over 512 MiB are cut (flagged)

Libraries

Libraries Poka uses or has assessed for this format, with the status, licence and language the registry records.

  • lz4_flex (candidate; MIT; Rust; https://github.com/pseitz/lz4_flex) — Pure Rust; frame::FrameDecoder implements Read; frame format needs std (block-only for no_std).
  • lz4 (lz4-rs) (candidate; MIT; Rust; https://docs.rs/lz4/latest/) — Bindings to the C LZ4 library via lz4-sys with a streaming Decoder; C dependency may be awkward for wasm32-wasip1.
  • lz4-sys (candidate; MIT; Rust; https://github.com/10xGenomics/lz4-rs) — Rust LZ4 sys package.; v1.11.1+lz4-1.10.0, updated 2024-09-26; matched on lib.rs, not tested
  • lzzzz (candidate; MIT; Rust; https://github.com/picoHz/lzzzz) — Full-featured liblz4 binding for Rust.; v2.0.0, updated 2024-12-06; matched on lib.rs, not tested

Sources

  • parsers/poka-lz4/src/main.rs
  • parsers/poka-lz4/plugin.json