eccodes/definitions/grib2/template.5.42.def

# Copyright 2005-2018 ECMWF.
#
# This software is licensed under the terms of the Apache Licence Version 2.0
# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
#
# In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
# virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
#

# TEMPLATE 5.42, Grid point and spectral data - CCSDS recommended lossless compression

include "grib2/template.5.packing.def";
include "grib2/template.5.original_values.def";

unsigned[1] ccsdsFlags : dump;
alias ccsdsCompressionOptionsMask=ccsdsFlags;

flagbit AEC_DATA_SIGNED_OPTION_MASK(ccsdsFlags,0)     = 0;

# AEC_DATA_3BYTE_OPTION_MASK was switched on in order to allow data stored
# with 17 <=bitsPerValue<= 24 to be stored in 3 rather than 4 bytes.
# This eliminates discretization errors that were occuring when it was off.
flagbit AEC_DATA_3BYTE_OPTION_MASK(ccsdsFlags,1)      = 1;

flagbit AEC_DATA_MSB_OPTION_MASK(ccsdsFlags,2)        = 1;
flagbit AEC_DATA_PREPROCESS_OPTION_MASK(ccsdsFlags,3) = 1;
flagbit AEC_RESTRICTED_OPTION_MASK(ccsdsFlags,4)      = 0;
flagbit AEC_PAD_RSI_OPTION_MASK(ccsdsFlags,5)         = 0;

unsigned[1] ccsdsBlockSize = 32 : dump;
unsigned[2] ccsdsRsi = 128      : dump;
alias referenceSampleInterval=ccsdsRsi;