HMP (Height MaP) Specs.
The HMP format is very simple:
There is a 100 octets header, at the beginning of the file, then the raw, unencoded height array,
in the form: height=(y*ysize+x);
The header has, so far, two fields: The first 4 octets are the map X size, then the next 4 are the map Y size.
The rest of the header bytes are reserved.