PHC / PHB

Status

Field	Value
Extension(s)	.phc, .phb
Common ecosystem	Brother / Baby Lock legacy card workflows
Format family	Legacy machine file
Satin Studio status	Researching
Open / import	No
Export	No
Confidence	Medium for PHC, lower for PHB.

What it is

PHC and PHB files are legacy Brother-family card or media formats. They appear to wrap Brother-style machine data rather than being modern PES files.

Satin Studio direction

PES/PEC covers modern Brother support first; these are older-library research leads.

Versions and variants

PHC and PHB should be treated as separate dialects until files prove their relationship.

File identification notes

Reported structure includes a header or container area plus a PEC-style block. That means some future support may be able to reuse PEC decoding after the wrapper is understood.

Observed structure notes

• PHB has been observed with a #PHB0003-style header lead, a color table near offset 0x71, and nested offsets that eventually locate PEC-style stitches.
• PHC has been observed with graphic height/stride near offset 0x4A, a Brother palette color table, PEC-style graphics, and a PEC-style stitch stream reached through offset and section-length fields.
• Both formats appear to wrap Brother/PEC-like payloads, but wrapper offsets and media metadata need validation.

Structure sketch

PHC/PHB are legacy Brother-family wrapper leads. The useful stitch data may be PEC-like after the wrapper is understood.

struct PhcPhbCandidate<'a> {
    wrapper_header: &'a [u8],           // card/media wrapper, unverified
    directory_or_metadata: Option<&'a [u8]>,
    possible_pec_block: Option<&'a [u8]>,
}

What we still need

Legacy files, card/media layout, PEC block location rules, and known reader validation.