# S102 -- S-102 Bathymetric Surface Product

Driver short name

S102

Build dependencies

libhdf5

Added in version 3.8.

This driver provides read-only support for bathymetry data in the S-102 format, which is a specific product profile in an HDF5 file.

S-102 files have two image bands representing depth (band 1), uncertainty (band 2) values for each cell in a raster grid area.

Note that positive values of depth mean values below the reference surface of the vertical datum. The `DEPTH_OR_ELEVATION` open option can be set to `ELEVATION` to expose depth values as elevation values, by negating their sign (i.e. positive values of elevation mean values above the reference surface)

Georeferencing is reported.

Nodata, minimum and maximum values for each band are also reported.

Supported versions of the specification are S-102 v2.1, v2.2 and v3.0.

Since GDAL 3.12, multiple feature instance groups per dataset (to encode grids using different vertical datums) are supported. In that case, each feature instance group is exposed as a GDAL subdataset, whose name is of the form `S102:"{filename.h5}":BathymetricCoverage.{XX}`.

## Driver capabilities

Supports Georeferencing

This driver supports georeferencing

Supports VirtualIO

This driver supports virtual I/O operations (/vsimem/, etc.)

## Open options

Open options can be specified in command-line tools using the syntax `-oo <NAME>=<VALUE>` or by providing the appropriate arguments to `GDALOpenEx()` (C) or `gdal.OpenEx` (Python). The following open options are supported:

- DEPTH_OR_ELEVATION=[DEPTH​/​ELEVATION]: Defaults to `DEPTH`. Whether to report depth or elevation. Positive values of depth mean values below the reference surface of the vertical datum. Positive values of elevation mean values above the reference surface of the vertical datum (which is the convention used by the BAG driver)

- NORTH_UP=[YES​/​NO]: Defaults to `YES`. Whether the top line of the dataset should be the northern-most one.

  This is the default behavior of most GDAL formats, but the native organization of the data in S-102 products is to have the first line of the grid being the southern-most one. This native organization can be exposed by the driver by setting this option to NO (in which case the 6th term of the geotransform matrix will be positive)

## Spatial metadata support

Starting with GDAL 3.9, GDAL can handle QualityOfSurvey (or QualityOfBathymetryCoverage in S102 v3.0) spatial metadata.

When such spatial metadata is present, the subdataset list will include a name of the form `S102:"{filename}":QualityOfSurvey` ( or `S102:"{filename}":QualityOfBathymetryCoverage` in S102 v3.0)

The `/QualityOfSurvey/featureAttributeTable` (`/QualityOfBathymetryCoverage/featureAttributeTable` in S102 v3.0) dataset is exposed as a GDAL Raster Attribute Table associated to the GDAL raster band. The pixel values of the raster match the `id` column of the Raster Attribute Table.

## See Also

- Implemented as s102dataset.cpp.

- S-102 Bathymetric Surface Product Specification

- BAG driver

- S-104 driver

- S-111 driver