1                                                           Sep 02, 2003
2                                                           W/NP11:SAG
3
4g2clib Library.
5
6This library contains "C" decoder/encoder
7routines for GRIB edition 2.  The user API for the GRIB2 routines
8is described in file "grib2c.doc".
9
10This "C" source code contains many uses of the C++
11comment style "//".  Please make sure you include the
12appropriate compiler option in the CFLAGS variable in the
13makefile to allow the use of "//" comment indicators.
14
15
16We have added support for PNG and JPEG2000 image compression
17algorithms within the GRIB2 standard.  If you would like
18to compile this library to utilize these GRIB2 Templates,
19make sure that -DUSE_PNG and -DUSE_JPEG2000 are specified
20in the DEFS variable in the makefile.  You will also need
21to download and install the external libraries listed below,
22if they are not already installed on your system.
23
24If you do not wish to bother with the external libs and
25don't need PNG and JPEG2000 support, you can remove the
26-DUSE_PNG and -DUSE_JPEG2000 flags from the DEFS variable
27in the makefile.
28
29
30-------------------------------------------------------------------------------
31
32     External Libraries:
33
34libjasper.a - This library is a C implementation of the JPEG-2000 Part-1
35              standard (i.e., ISO/IEC 15444-1).  This library is required
36              if JPEG2000 support in GRIB2 is desired.  If not, remove
37              the -DUSE_JPEG2000 option from the DEFS variable
38              in the makefile.
39
40              Download version jasper-1.700.2 from the JasPer Project's
41              home page, http://www.ece.uvic.ca/~mdadams/jasper/.
42
43              More information about JPEG2000 can be found at
44              http://www.jpeg.org/JPEG2000.html.
45
46libpng.a      This library is a C implementation of the Portable Network
47              Graphics PNG image compression format.  This library is required
48              if PNG support in GRIB2 is desired.  If not, remove
49              the -DUSE_PNG option from the DEFS variable
50              in the makefile.
51
52              If not already installed on your system, download version
53              libpng-1.2.5 from http://www.libpng.org/pub/png/libpng.html.
54
55              More information about PNG can be found at
56              http://www.libpng.org/pub/png/.
57
58libz.a        This library contains compression/decompression routines
59              used by libpng.a for PNG image compression support.
60              This library is required if PNG support in GRIB2 is desired.
61              If not, remove the -DUSE_PNG option from the DEFS variable
62              in g2lib/makefile.
63
64              If not already installed on your system, download version
65              zlib-1.1.4 from http://www.gzip.org/zlib/.
66
67
68