CSD

Status

What it is

CSD is a legacy consumer embroidery format encountered in older design collections and conversion lists.

Satin Studio behavior

Satin Studio documents this format for identification and inspection. It does not open or export the file.

Versions and variants

Satin Studio checks the file signature and dialect rather than trusting the extension. An unrecognized version remains unopened, with the original file preserved for inspection.

File identification notes

Brand, version, and byte behavior are uncertain.

Observed structure notes

• CSD has been observed with an eight-byte identifier followed by encoded thread and stitch data. Some readers derive a decode table from the first identifier byte or a fixed 0x0C seed.
• Observed layout after decoding: 16 RGB thread entries, two unknown bytes, a 14-entry color order table, then three-byte stitch records.
• In observed stitch records, byte 0 carries sign and control bits, byte 1 is Y magnitude, and byte 2 is X magnitude. Byte 0 values 0xF8, 0x87, or 0x91 terminate the stream in observed readers.

Structure sketch

CSD is still uncertain, but observed encrypted/encoded files fit this high-level shape:

struct CsdCandidate<'a> {
    identifier: [u8; 8],
    encoded_threads: [u8; 16 * 3],      // 16 RGB entries after decoding
    unknown: [u8; 2],
    color_order: [u8; 14],
    records: &'a [CsdRecord],           // decoded three-byte records
}

struct CsdRecord {
    control_and_sign: u8,               // bit 0x20 negates x; bit 0x40 negates y
    y: u8,
    x: u8,
}

Compatibility evidence

The notes above help identify and inspect the format; they do not imply import or export support. Keep the original file and record the machine and software that produced it.