Codec support

xfh decodes 53 XPK codec identifiers in pure Python.

Evidence	Codecs
Original Amiga fixture	ACCA, BLFH, BLZW, BZP2, CBR0, DLTA, DUKE, ELZX, ENCO, FAST, FBR2, FEAL, FRLE, GZIP, HFMN, HUFF, IDEA, ILZR, IMPL, LHLB, LZBS, LZCB, LZW2, LZW3, LZW4, LZW5, MASH, NONE, NUID, NUKE, PPMQ, RAKE, RDCN, RLEN, SASC, SDHC, SHID, SHRI, SHSC, SLZ3, SLZX, SQSH, ZENO
Exact historical alias	CBR1, FRHT
Independent or source-derived fixture	ARTM, CRM2, CRMS, CYB2, PWPK, SHR3, SMPL, TDCS

Original fixtures were packed and unpacked by preserved Amiga software under headless UAE, then decoded byte-exactly by xfh. The fixture manifest records their provenance, sizes, and hashes.

BLFH, ENCO, FEAL, IDEA, NUID, and SHID require a password. BLFH supports packed and unpacked ECB, OFB, CFB, and CBC streams across modes 0–100. These obsolete ciphers are provided only for data recovery.

Evidence gaps

ARTM and SHR3: no original library is available.
CYB2: its preserved library does not expose a usable packing path.
TDCS: no original library or packed sample is available.
SMPL: the original packer emitted raw chunks for all tested inputs.
CRM2 and CRMS: verified with an independent Crunch-Mania implementation.
PWPK: verified with the original PPMC utility and Ancient, but wrapped in a source-built XPK container.

Unsupported preserved codecs

CYB1, DHUF, and DMCB are not implemented. Their preserved packers cannot produce a compressed fixture suitable for safe decoder development:

CYB1 is decrunch-only.
DHUF copies input instead of emitting compressed chunks.
DMCB emits raw chunks for small inputs and hangs on larger probes.

Historical packed samples would allow these decoders to be completed.