JEF embroidery file format

What a JEF file stores

Two details set JEF apart from other formats.

Colours are palette numbers. A JEF file doesn't contain a red, green and blue value for each thread. It contains the number of a thread in Janome's own colour list, which pyembroidery's implementation reproduces with 78 colours. The machine shows that Janome thread on screen, and Janome's own software can name it. Any colour that isn't in the palette has to be replaced by its nearest neighbour when a file is saved as JEF.

The hoop is part of the file. The header records which hoop the design was laid out for, for example the 126 × 110 mm or the 140 × 200 mm field, together with the distance from the design's edges to the edges of that hoop.

The stitches themselves are short moves of up to 12.7 mm each, with separate commands for jumps and colour changes. JEF has no dedicated trim command, so trims travel as short jump sequences; how they are cut depends on the machine.

JEF+, JPX and SEW

Janome's own documentation describes two newer variants. JEF+ is an editable container that can hold several JEF designs and knows larger hoops; JPX adds a background picture used for cutwork, AcuFil and similar functions. Both are working formats of Janome's software and newer machines. The plain JEF is still what designs are sold in and what every Janome embroidery machine reads.

Before JEF, Janome, Elna and Kenmore machines used SEW. SEW files still turn up in old collections; they also point to a Janome palette, although not an identical one, and convert to JEF without loss of stitches.

Which machines read JEF

Every Janome and Elna embroidery machine reads JEF. Some also read DST: the MB-4S, MB-7 and Skyline S9 list it, but the Continental M17, MC550E, MC9850 and MC400E don't, so a DST-only download can leave a Janome owner stuck. Elna's eXpressive 830 reads DST, while the eXpressive 860 manual doesn't list it.

Other brands read JEF as a second format: bernette's b70 DECO and b79, BERNINA's B 880 and B 790 with the Embroidery PLUS upgrade, and the Husqvarna Viking and Pfaff flagships with 15 formats.

How to open and check a JEF file

The free embroidery file viewer opens JEF files in the browser and shows the size, stitch count and the Janome colours. It is worth a look before you transfer a design, because the stored hoop and the design's real size don't always match: a design laid out for the 140 × 200 mm field won't sew in a 126 × 110 mm hoop even when it looks small on screen. The hoop sizes guide lists the fields of popular Janome models.

Converting to and from JEF

• PES to JEF and JEF to PES move between two brand palettes, so a shade can change to its nearest neighbour.
• DST to JEF gives a colourless file its first colours: Janome palette entries chosen by the converter. Correct them with the thread chart.
• JEF to DST drops the palette numbers, because DST stores no colours.

The stitches, their order and the design's size stay the same in every direction.

JEF files from Embroidly

Every library design includes a JEF file in each of its three sizes. Our exporter maps each thread of the design to the nearest Janome palette colour and keeps neighbouring blocks apart when two of them would map to the same colour, so you can still tell them apart on the machine's screen. Every file is read back after writing and checked against the digitized design.