Hachoir is the french name for a mincer: a tool used by butchers to cut meat. Hachoir is also a tool written for hackers to cut file or any binary stream. A file is split in a tree of fields where the smallest field can be just a bit. There are various field types: integer, string, bits, padding, sub file, etc. WWW: http://hachoir.org/wiki/hachoir-core