Exporting to FSV-25 Format (*.nc)

Echoview supports the export of Sv raw variable data derived from Furuno FSV-30 (Research version) *.fsv files to the ICES SONAR-netCDF4 *.nc file format. Where a position and/or a heading variable are used by the platform, GPS and heading data will also be written to the file format. Heave, pitch and roll are not currently supported.

The output *.nc file may be added to a fileset.

Export via Echogram menu

1. Select a Furuno FSV-30 (Research version) Sv raw variable echogram.
2. On the Echogram menu, select Export, To FSV-25 Format ...
3. On the Export to FSV-25 Format dialog box enter a file name.
4. Click Save.

Export via Dataflow window

1. On the Dataflow window, select a Furuno FSV-30 (Research version) Sv raw variable.
2. Right-click and on the Shortcut menu, then select Export, To ICES netCDF4 Format ...
3. On the Export to ICES netCDF4 Format dialog box enter a file name.
4. Click Save.

Note: On the export progress dialog box you can use the Cancel export button. This will stop the export and delete the last partial *.nc file.

ICES SONAR-netCDF4 Format

Echoview exports underlying Sv sample data such that it conforms to the ICES SONAR-netCDF4 (version 1.1, in progress) Type 2 equations from Macaulay and Peña (2018). Contact Furuno Electric Co., Ltd for further details.

The ICES SONAR-netCDF4 convention specifies data obligations for elements of the file format and describes the handling for missing data. Data obligation options include:

• Mandatory
• Mandatory if applicable or available
• Recommended
• Optional

Where an element is 'Mandatory' and a value is available, the value is output to the *.nc file.

Where an element is 'Mandatory', or the element is 'Mandatory if applicable or available' and it is applicable, and the value is unavailable, a default Echoview calibration value is output for the element.

For elements that are 'Optional', 'Recommended', or 'Mandatory if applicable or available' and it is not applicable, Echoview outputs an element value of '+NaN'.

Notes:

• The export supports only one sound speed value per file. The export supports only one absorption coefficient per frequency. Otherwise, the export aborts.
• When sound speed, frequency or absorption coefficient are absent from the *.fsv file, NAN is assigned as the item's export value.
• 3 dB beam angles (MajorAxis3dbBeamAngle, MinorAxis3dbBeamAngle and MinorAxis3dbBeamAngleTransmit) that may be evaluated from angle data in the file, are exported.
• The FSV-30 (Research version) designation of 'L' for Low gain variable is not supported for derived variables when exported *.nc files are added to a fileset.
• The export does not support:
  • a transducer offset configured under the Transducer Properties dialog box
  • S-mode data
  • the imaginary component of the FSV-30 (Research version) data
• See also COM Scripting: EvAcousticVariable.ExportFSV25.
• EvFile.ExportFSV25All exports all the Furuno FSV-30 (Research version) *.fsv raw Sv variable data in an EV file to a single *.nc file.
• When using COM scripting to run EvFile.ExportFSV25All, and no variables are suitable for export, the method returns the message "No variables to export."
• See also FSV-30 (Research version) notes.
• Exported *.nc files are generally larger than the original *.fsv files.

See also

Exporting in Echoview
About exporting data
About Exporter objects
Export file formats
Furuno data files
About exporting measurement data