edhartnett / nceplibs-g2c

This library contains C decoder/encoder routines for GRIB edition 2.

NCEPLIBS-g2c

This library contains C decoder/encoder routines for GRIB edition 2.

This is related to the NCEPLIBS project.

For complete documentation see the latest NCEPLIBS-g2c documentation. For more about GRIB2 see the NCEP WMO GRIB2 Documentation. For the WMO GRIB2 templates and tables see WMO Information Management GRIB2 GitHub repository.

The NCEPLIBS-g2c library is used by the wgrib2, GRaDS, and Model Evaluation Tools (MET) projects, among others.

To submit bug reports, feature requests, or other code-related issues including installation and usage questions, please create a GitHub issue. For general NCEPLIBS inquiries, contact Ed Hartnett (secondary point of contact Alex Richert).

Related NCEPLIBS Projects

Repository	Notes
NCEPLIBS-g2	Fortran implementation of the GRIB 2 functions
NCEPLIBS-grib_util	A collection of GRIB1 and GRIB2 utilities
NCEPLIBS-g2tmpl	Utilities for GRIB2 templates

Authors

Stephen Gilbert, Wesley Ebisuzaki, Boi Vuong, Edward Hartnett

Code Manager: Hang Lei, Ed Hartnett

Prerequisites

• libjasper.a - This library is a C implementation of the JPEG-2000 Part-1 standard (i.e., ISO/IEC 15444-1). Tested version: jasper-1.900.1. More information about JPEG2000 can be found at http://www.jpeg.org/JPEG2000.html.

• libpng.a - This library is a C implementation of the Portable Network Graphics PNG image compression format. Tested version: libpng-1.2.44. More information about PNG can be found at http://www.libpng.org/pub/png/.

• libz.a - This library contains compression/decompression routines used by libpng.a for PNG image compression support. Tested version: zlib-1.2.6.

• openjpeg.a - OpenJPEG is an open-source JPEG 2000 codec written in C language. OpenJPEG is only used if CMake build option USE_OpenJPEG is turned on.

Building

Download the tarball from the release page and unpack it, and cd into the main directory of the library. Then run the following commands, substituting your directory locations for the CMAKE_INSTALL_PREFIX (where the NCEPLIBS-g2c library will be installed), and the CMAKE_PREFIX_PATH (where the build will look for dependencies):

mkdir build
cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr/local/NCEPLIBS-g2c -DCMAKE_PREFIX_PATH=/usr/local/jasper-3.0.5 ..
make
make test
make install

The NCEPLIBS-g2c library supports the PNG and JPEG2000 methods of image compression algorithms within the GRIB2 standard.

By default the library uses Jasper for JPEG functionality, use the USE_OpenJPEG to use the OpenJPEG library instead.

References

Hartnett, E., Lei, H., Curtis, B, Gerheiser K., Presentation - Improving Documentation, Testing, Process, and Code for Legacy NOAA GRIB2 C Fortran Libraries, NCAR Improving Scientific Software, April 2022. .

Kumar, V. Krishna, Gilbert, Stephen A., GRIB2 conversion and its usage at NCEP, 14-18 November 2005, 10th Workshop on Meteorological Operational Systems ECMWF User Orientation, retrieved on July 27, 2021 from https://www.yumpu.com/en/document/view/11925806/grib2-conversion-and-its-usage-at-ncep.

Disclaimer

The United States Department of Commerce (DOC) GitHub project code is provided on an "as is" basis and the user assumes responsibility for its use. DOC has relinquished control of the information and no longer has responsibility to protect the integrity, confidentiality, or availability of the information. Any claims against the Department of Commerce stemming from the use of its GitHub project will be governed by all applicable Federal law. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply their endorsement, recommendation or favoring by the Department of Commerce. The Department of Commerce seal and logo, or the seal and logo of a DOC bureau, shall not be used in any manner to imply endorsement of any commercial product or activity by DOC or the United States Government.