This is great! Where does one get a copy of this program?

-- Geoff

"G. van Toornenberg" wrote in
:

Subject: GISTrans: Maptech / NDI BSB Chart Format
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I did it! I just wrote a program that reads NOAA BSB chart
files
and converts them to BMP files! BMP files are not the final goal of my
project, but it served as a proof-of-concept. Next I will want to
write routines to extract pieces of the file at full resolution for
printing, and routines to filter pieces of the chart for display at
lower resolution on the screen. (One of the terrible things about
most chart display programs is that they all sub-sample the charts
instead of filtering it down). How did I figure out how to read the
BSB files?

If you recall, I have been trying to reverse engineer the
file
formats of those nautical charts. When I am between projects I often
do a WEB search for the BSB file format to see if someone else has
published a hack for them. Monday I hit a NOAA project status report
that mentioned some guy named Marty Yellin who had recently completed
writing a program to convert BSB files to other file formats! I
searched for him and found him mentioned as a contact person for some
NOAA program. I was composing a letter to him in my head, or
considering calling the NOAA phone number and asking for his extension
number, when I saw another NOAA status report indicating that he had
retired in 1998. His name showed up in a few more reports, one of
which said that he was the inventor of the BSB file format, that it
was patented (#5,727,090), and that the patent had been licensed to
Maptech (the evil company that will not allow anyone using their file
format to convert them to non-proprietary formats). Patents are
readily available on the WEB at the IBM patent server and this one is
in the dtabase! I printed up a copy of the patent and of course it
describes very nicely (despite the usual typos and omissions of
referenced items in the figures) how to write one of these BSB files!

I was considering talking to a patent lawyer about the
legality of
using information in the patent to read files without getting a
license, when I noticed that the patent is only claiming programs that
WRITE the file format. I have noticed this before in RF patents where
they describe how to make a receiver and never bother to claim a
transmitter. The logic is that the transmitter is no good to anybody
unless they license receivers from the patent holder. But I think they
did it backwards here! They should have claimed a program that can
READ the described file format. Now I can read the files, build
programs that read the files, and even sell them without violating the
claims in the patent! As long as I never try to write one of the evil
BSB files, I'm OK!!!

If you ever need to read these BSB chart programs, drop me a
note. I would be happy to send you a copy of this conversion program.

... later email ...

Well, here is my little proof of concept program. I hereby
give
you permission to distribute it freely, modify for you own use, etc.
I built it as a "WIN32 Console application" which means it runs in an
MS DOS box under Microsoft Windows. But the only Windows specific
stuff in it are the include files for the BMP file headers. If you
ripped out the BMP code it should compile under UNIX or anyplace else.
I'd be overjoyed to have you announce it to GISTrans or
anywhere
else. I'm philosophically opposed to the proprietary treatment of the
BSB file format and I want to break it open! Chart data for the
People!