Embroidery format VP3
VP3 format is a Pfaff format. Unlike most other embroidery formats. It's divided into stitchblocks. Conceptually it's typical to think of embroidery rather than the set of low level commands which control the machine but as sets of unbroken stitches in a particular color. While this is quite common at the level of embroidery software, most formats typically consist of large dumps of direct embroidery commands with some various cruft for the machines in question. For example, PEC blocks (in PEC files and PES files) contain 1 bit graphics files.
VP3 consists of: a magic code, some hoop and design information, a number for the number of stitch blocks and stitch blocks.
Each vp3 stitchblock contains: Thread information. (Brand, Catalog Number, and Description) The position of the end of the block. And stitches.
Also See
https://community.kde.org/Projects/Liberty/File_Formats/Viking_Pfaff http://www.jasonweiler.com/VP3FileFormatInfo.html