Re: Compressed netCDF library available

• To: noon@xxxxxxxxxxxxxxxxxxxx
• Subject: Re: Compressed netCDF library available
• From: Arlindo da Silva <dasilva@xxxxxxxxxxxxxxxxx>
• Date: Thu, 9 Apr 1998 12:17:02 -0400 (EDT)

Bill,

> 
> Arlindo -- I haven't looked at their library.  Do you have a link 
> to it?  --Bill
> 
> > If I am not mistaken, this is precisely what MFHDF (NCSA's NetCDF API
> > for HDF) does thru an interface to zlib. Have you compared your
> > approach with theirs? I makes me a little worried to have yet another
> > *DF format around.
> 

The HDF home page is:

        http://hdf.ncsa.uiuc.edu/

For information on data compression look at the FAQ:

    http://hdf.ncsa.uiuc.edu/HDF-FAQ.html#18


Quoting:

18) Does HDF support data compression?

HDF 4.0 (and later releases) supports a low-level compression
interface, which allows any data-object to be
compressed using a variety of algorithms. 

Currently only three compression algorithms are supported: Run-Length
Encoding (RLE), adaptive Huffman, and an
LZ-77 dictionary coder (the gzip 'deflation' algorithm). Plans for
future algorithms include an Lempel/Ziv-78 dictionary
coding, an arithmetic coder and a faster Huffman algorithm. 

HDF 4.0 (and later releases) supports n-bit compression for SDSs. 

HDF 4.0 (and later releases) supports RLE (Run Length Encoding),
IMCOMP, and JPEG compression for raster images. 

New with HDF 4.1 is support for "chunking" and "chunking with
compression". Data chunking allows an n-dimensional
SDS or GR image to be stored as a series of n-dimensional chunks. See
the HDF User's Guide for more information. 


-- 
Arlindo da Silva
dasilva@xxxxxxxxxxxxx

• References:
  • Re: Compressed netCDF library available
    • From: noon