Janome Embroidery Format

The Janome Embroidery Format .jef (and .sow) files contain a header and stitch instructions, but does not contain any obvious signature bytes. The only signature is to see if the thread change table is the correct size and the file length is right for the number of thread changes and the number of stitches. For the .jef+ format there is extra data after the thread tables, then the 32bit aligned string "JANO", "ME\0\0", then a 32bit number (1 for a 1 thread pattern), then a 32bit bitmap-start offset -- with ruins the .jef 'signature', but now we have the string "JANOME".

The header contains a date, number of thread changes, number of stitches, stitch extent rectangle, other optional rectangles, and two thread change tables (the first is thread colour). The stitch instructions are pairs of 8 bit offsets (starting from the centre of the design) with an escape sequence for move, thread change, and end of pattern.

Offset	Description
0x0000	Stitch-start offset
0x0004	Flags, domain: 0x1, 0xa
0x0008	Date ASCII YYYY
0x000C	Date ASCII MMDD
0x0010	TIME ASCII HHMM
0x0014	TIME ASCII SS00
0x0018	Thread-load-count
0x001C	Stitch-count
0x0020	Hoop-code, domain: 0 "A 126mm x 110mm", 1 "C 50mm x 50mm", 2 "B 140mm x 200mm", 3, 4
0x0024	Stitch-extent-left 0.1mm units from centre
0x0028	Stitch-extent-top
0x002C	Stitch-extent-right
0x0030	Stitch-extent-bottom
0x0034	box2-left -- minus 1 appears to indicate not used
0x0038	box2-top
0x003C	box2-right
0x0040	box2-bottom
0x0044	box3-left
0x0048	box3-top
0x004C	box3-right
0x0050	box3-bottom
0x0054	box4-left
0x0058	box4-top
0x005C	box4-right
0x0060	box4-bottom
0x0064	box5-left
0x0068	box5-top
0x006C	box5-right
0x0070	box5-bottom
0x0074	thread-colour-table, domain: 0x01 - 0x4e -- there are 79 colours in the Janome catalogue
+	Thread-load-count * 4
+	0x0000 thread-type-table, domain: 0xd
+	Thread-load-count * 4
+	0x0000 jef plus zero
+	0x0004 jef plus zero
+	0x0008 jef plus "JANO"
+	0x000C jef plus "ME"
+	0x0010 jef plus bitmap-count (may be)
+	0x0014 jef plus bitmap-start offset
...
Stitch-	start stitch-table pairs of signed 8bit values, either 0x80 and command or dx and dy
...
bitmap-	start jef plus bitmap