OLCI O2A Harmonisation - Command Line Description |

### Command Line Description

Since the OLCI O2A Harmonisation processor makes use of the SNAP graph processing framework, it can be used also as a command line tool. The graph processing is invoked by the command

- ${OPTTBX-INSTALL-DIR}/bin/gpt

To obtain general help on the graph processing, use the command

- ${OPTTBX-INSTALL-DIR}/bin/gpt -h

Specific help on the OLCI O2A Harmonisation processor can be obtained with

- ${OPTTBX-INSTALL-DIR}/bin/gpt -h OlciO2aHarmonisation

In this case, information on the usage and a list of all available parameters are given.

The OLCI O2A Harmonisation processor parameters can also be specified via a graph xml file. A possible graph xml file could look like the following. (Note that in principle it is not necessary to explicitly set parameters if default values shall be used).

        <graph id="OlciHarmonisationTest">
            <version>1.0</version>
            <node id="slope">
                <operator>OlciHarmonisation</operator>
                <sources>
                    <sourceProduct>${sourceProduct}</sourceProduct>
                </sources>
                <parameters>
                    <demAltitudeBandName>myAltitude</demAltitudeBandName>
                </parameters>
            </node>
        </graph>

This graph can be invoked by the following call on the command line:

        gpt <graph-file.xml> -SsourceProduct=<path-to-source-file>