[comp.sys.dec] Binary data formats

gg10@prism.gatech.EDU (Galloway, Greg) (12/03/89)

Problem:

We have code and data which is developed on a set of MicroVAXes and then
ported to other larger and faster (non-VAX) machines to do the processing.
The most difficult task is converting all the necessary files to ASCII,
sending them to the larger machine and then converting them back to binary.
This usually means having well over a dozen file conversion programs.
Data consists of either characters, integers, booleans, or floating point.
The data consists of images (real and byte), facet information for models,
topographical height fields and associated color and infared files, etc.

* Boolean do not pose a problem when sending between machines as long as
  they are stored as a single (8-bit) byte with 0 as false and non-0 as true.

* Characters are only 8-bit bytes on all machines, far as I know, and 
  are in either ASCII or EBCDIC format.

* Integer data (to my knowledge) only consists of two types:

  - Big-endian, or Intel-type: Most significant byte first (16 or 32 bit)
  - Little-endian, or Motorola-type: Least significant byte first

* Floating point data is the greatest obstacle.  Almost all machines that
  I have been able to find use ANSI-IEEE Std (1975) for floating point.
  The only exceptions are the VAX and CONVEX (the CONVEX has IEEE as 
  optional hardware).

Questions:

* Does anyone know of any other formats for characters, integers or 
  floating point?

* Are there any binary file formats in existance which attempt to attack
  this problem?

I am in the process of attempting to develop a public-domain tag-based
binary file format which will tag the datatype with the data so that the
application program can read the data and the type of machine on which
it was created and convert as necessary to be useable.  This file format
will be similar to the Tiff file format developed by Microsoft and Aldus
for use in Desktop publishing but will support floating point as well
as integer data.

I have heard of the IFF format from Amiga.  Does any have a write-up of
this standard?  Does it support various formats between various machines?

If anyone has any comments or interest I would like to hear from them.

Please reply by E-mail (I don't subscribe to all these newgroups).

Thanks,

Greg Galloway
Georgia Tech Research Institute
Georgia Institute of Technology
gg10@prism.gatech.edu
(404)894-3357