grdzip - Efficient compression of 2-byte integer grids

grdzip is a utility for the efficient compression of 1-, 2-, or 4- byte integer grids prior to transmission over the Internet. It takes advantage of the structure of data grids by using double differences and encoding these differences in a variable-width bit-packing format; these packed bits are then written to stdout via the bzip2 compression library. Typically, the resulting compressed files are 25 % smaller than what bzip2 alone can produce and less than half of what gzip can do.

grdzip is developed and maintained by Paul Wessel.

More information about GRDZIP

  • Wessel, P., 2003, Compression of large data grids for Internet transmission, Computers & Geosciences, 29 (5), 665-671 [PDF].

    Availability of grdzip source code:

    Availability of grdzip executables:

    I maintain a set of precompiled executables for a variety of platforms. Download the one you need (SHIFT-CLICK), rename it (remove the extension) and make it executable:
    1. For grdzip executable for Linux/Intel (RH7.2), click grdzip.linux
    2. For grdzip executable for Sparc Solaris, click grdzip.sparc
    3. For grdzip executable for HP-UX, click grdzip.hpux
    4. For grdzip executable for SGI IRIX, click grdzip.sgi
    5. For grdzip executable for AIX/RS600, click grdzip.rs6000
    6. For grdzip executable for MacOSX, click grdzip.macosx
    7. For grdzip executable for Windows, click grdzip.exe.win32
    The latest files for version 1.0 were created April 4, 2002. Note, as time goes by some of these may no longer work with updated operating systems.

    Last update January 6, 2014 by Paul Wessel