An SPV file begins with an 39-byte header:
Header ⇒ 01 00 (i1 | i3)[version] 01 (00 | 01) byte*21 00 00 int[table-id] byte*4
version is a version number that affects the interpretation of
some of the other data in the member. We will refer to “version 1”
and “version 3” later on and use v1(…) and v3(…) for
version-specific formatting (as described previously).
table-id is a binary version of the
tableId attribute in
the structure member that refers to the detail member. For example,
would be 0xdca00003.
The meaning of the other variable parts of the header is not known.