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<title>HDF5 --- Hierarchical Data Format Release 5 (HDF5)</title>
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<h1>HDF5 --- Hierarchical Data Format Release 5 (HDF5)</h1>
This driver intended for HDF5 file formats importing. This
modification is
suited for use with remote sensing data and fully compatible with
underlying HDF5. This driver can import HDF5-EOS files. Currently EOS use
HDF5 for data storing (telemetry form `Aura' satellites). In
the future they will switch to HDF5 format, which will be used for
telemetry from `Aura' satellite.<p>
<h2>Multiple Image Handling (Subdatasets)</h2>
Hierarchical Data Format is a container for several different datasets.
For data storing. HDF contains multidimensional arrays filled by data.
One HDF file may contain several arrays. They may differ in size,
number of dimensions.<p>
The first step is to get a report of the components images (arrays) in the
file using <b>gdalinfo</b>, and
then to import the desired images using gdal_translate.
The <b>gdalinfo</b> utility lists all multidimensional subdatasets from the
input HDF file. The name of individual images (subdatasets) are assigned to
the <b>SUBDATASET_n_NAME</b> metadata item. The description for each image is
found in the <b>SUBDATASET_n_DESC</b> metadata item. For HDF5 images the
subdataset names will be formatted like this:<p>
<i>HDF5:file_name:subdataset</i><p>
where:<br> <i>file_name</i> is the name of the input file, and<br>
<i>subdataset</i> is the dataset name of the array to use (for internal use in
GDAL).<p>
On the second step you should provide this name for <b>gdalinfo</b> or
<b>gdal_translate</b> for actual reading of the data.<p>
For example, we want to read data from the OMI/Aura Ozone (O3) dataset:<p>
<pre>
$ gdalinfo OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5
Driver: HDF5/Hierarchical Data Format Release 5
Size is 512, 512
Coordinate System is `'
Subdatasets:
SUBDATASET_-1_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":APrioriLayerO3
SUBDATASET_-1_DESC=[1645x60x11] APrioriLayerO3 (32-bit floating-point)
SUBDATASET_0_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":AlgorithmFlags
SUBDATASET_0_DESC=[1645x60] AlgorithmFlags (8-bit unsigned character)
SUBDATASET_1_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":CloudFraction
SUBDATASET_1_DESC=[1645x60] CloudFraction (32-bit floating-point)
SUBDATASET_2_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":CloudTopPressure
SUBDATASET_2_DESC=[1645x60] CloudTopPressure (32-bit floating-point)
SUBDATASET_3_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":ColumnAmountO3
SUBDATASET_3_DESC=[1645x60] ColumnAmountO3 (32-bit floating-point)
SUBDATASET_4_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":LayerEfficiency
SUBDATASET_4_DESC=[1645x60x11] LayerEfficiency (32-bit floating-point)
SUBDATASET_5_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":NValue
SUBDATASET_5_DESC=[1645x60x10] NValue (32-bit floating-point)
SUBDATASET_6_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":O3BelowCloud
SUBDATASET_6_DESC=[1645x60] O3BelowCloud (32-bit floating-point)
SUBDATASET_7_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":QualityFlags
SUBDATASET_7_DESC=[1645x60] QualityFlags (8-bit unsigned integer)
SUBDATASET_8_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":Reflectivity331
SUBDATASET_8_DESC=[1645x60] Reflectivity331 (32-bit floating-point)
SUBDATASET_9_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":Reflectivity360
SUBDATASET_9_DESC=[1645x60] Reflectivity360 (32-bit floating-point)
SUBDATASET_10_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":Residual
SUBDATASET_10_DESC=[1645x60x10] Residual (32-bit floating-point)
SUBDATASET_11_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":ResidualStep1
SUBDATASET_11_DESC=[1645x60x10] ResidualStep1 (32-bit floating-point)
SUBDATASET_12_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":ResidualStep2
SUBDATASET_12_DESC=[1645x60x10] ResidualStep2 (32-bit floating-point)
SUBDATASET_13_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":SO2index
SUBDATASET_13_DESC=[1645x60] SO2index (32-bit floating-point)
SUBDATASET_14_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":Sensitivity
SUBDATASET_14_DESC=[1645x60x10] Sensitivity (32-bit floating-point)
SUBDATASET_15_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":StepOneO3
SUBDATASET_15_DESC=[1645x60] StepOneO3 (32-bit floating-point)
SUBDATASET_16_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":StepTwoO3
SUBDATASET_16_DESC=[1645x60] StepTwoO3 (32-bit floating-point)
SUBDATASET_17_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":TerrainPressure
SUBDATASET_17_DESC=[1645x60] TerrainPressure (32-bit floating-point)
SUBDATASET_18_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":UVAerosolIndex
SUBDATASET_18_DESC=[1645x60] UVAerosolIndex (32-bit floating-point)
SUBDATASET_19_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":dN_dR
SUBDATASET_19_DESC=[1645x60x10] dN_dR (32-bit floating-point)
SUBDATASET_20_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":dN_dT
SUBDATASET_20_DESC=[1645x60x10] dN_dT (32-bit floating-point)
SUBDATASET_21_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":GroundPixelQualityFlags
SUBDATASET_21_DESC=[1645x60] GroundPixelQualityFlags (8-bit unsigned integer)
SUBDATASET_22_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":Latitude
SUBDATASET_22_DESC=[1645x60] Latitude (32-bit floating-point)
SUBDATASET_23_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":Longitude
SUBDATASET_23_DESC=[1645x60] Longitude (32-bit floating-point)
SUBDATASET_24_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":RelativeAzimuthAngle
SUBDATASET_24_DESC=[1645x60] RelativeAzimuthAngle (32-bit floating-point)
SUBDATASET_25_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":SolarAzimuthAngle
SUBDATASET_25_DESC=[1645x60] SolarAzimuthAngle (32-bit floating-point)
SUBDATASET_26_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":SolarZenithAngle
SUBDATASET_26_DESC=[1645x60] SolarZenithAngle (32-bit floating-point)
SUBDATASET_27_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":TerrainHeight
SUBDATASET_27_DESC=[1645x60] TerrainHeight (8-bit integer)
SUBDATASET_28_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":ViewingAzimuthAngle
SUBDATASET_28_DESC=[1645x60] ViewingAzimuthAngle (32-bit floating-point)
SUBDATASET_29_NAME=HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":ViewingZenithAngle
SUBDATASET_29_DESC=[1645x60] ViewingZenithAngle (32-bit floating-point)
Corner Coordinates:
Upper Left ( 0.0, 0.0)
Lower Left ( 0.0, 512.0)
Upper Right ( 512.0, 0.0)
Lower Right ( 512.0, 512.0)
Center ( 256.0, 256.0)
</pre>
Now select one of the subdatasets, described as
<tt>[1645x60] CloudFraction (32-bit floating-point)</tt>:<p>
<pre>
$ gdalinfo HDF5:"OMI-Aura_L2-OMTO3_2005m0326t2307-o03709_v002-2005m0428t201311.he5":CloudFraction
Driver: HDF5Image/HDF5 Dataset
Size is 60, 1645
Coordinate System is:
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
TOWGS84[0,0,0,0,0,0,0],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.0174532925199433,
AUTHORITY["EPSG","9108"]],
AXIS["Lat",NORTH],
AXIS["Long",EAST],
AUTHORITY["EPSG","4326"]]
GCP Projection = GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],TOWGS84[0,0,0,0,0,0,0],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9108"]],AXIS["Lat",NORTH],AXIS["Long",EAST],AUTHORITY["EPSG","4326"]]
GCP[ 0]: Id=, Info=
(0.5,0.5) -> (261.575,-84.3495,0)
GCP[ 1]: Id=, Info=
(2.5,0.5) -> (240.826,-85.9928,0)
GCP[ 2]: Id=, Info=
(4.5,0.5) -> (216.754,-86.5932,0)
GCP[ 3]: Id=, Info=
(6.5,0.5) -> (195.5,-86.5541,0)
GCP[ 4]: Id=, Info=
(8.5,0.5) -> (180.265,-86.2009,0)
GCP[ 5]: Id=, Info=
(10.5,0.5) -> (170.011,-85.7315,0)
GCP[ 6]: Id=, Info=
(12.5,0.5) -> (162.987,-85.2337,0)
<pre>... 3000 GCPs are read from the file if Latitude and Longitude arrays are presents </pre>
Corner Coordinates:
Upper Left ( 0.0, 0.0)
Lower Left ( 0.0, 1645.0)
Upper Right ( 60.0, 0.0)
Lower Right ( 60.0, 1645.0)
Center ( 30.0, 822.5)
Band 1 Block=60x1 Type=Float32, ColorInterp=Undefined
Open GDAL Datasets:
1 N DriverIsNULL 512x512x0
</pre>
You may use <b>gdal_translate</b> for reading image bands from this
dataset.<p>
Note that you should provide exactly the contents of the line marked
<b>SUBDATASET_n_NAME</b> to GDAL, including the <b>HDF5:</b> prefix.<p>
This driver is intended only for importing remote sensing and geospatial
datasets in form of raster images(2D or 3D arrays). If you want explore all
data contained in HDF file you should use another tools (you can find
information about different HDF tools using links at end of this page).
<h2>Georeference</h2>
There is no universal way of storing georeferencing in HDF files. However,
some product types have mechanisms for saving georeferencing, and some of
these are supported by GDAL. Currently supported are (<i>subdataset_type</i>
shown in parenthesis):<p>
<ul>
<li> HDF5 OMI/Aura Ozone (O3) Total Column 1-Orbit L2 Swath 13x24km (<B>Level-2 OMTO3</B>)
</ul>
<h2>Metadata</h2>
No Metadata are read at this time from the HDF5 files.
<h2>Driver building</h2>
This driver builded on top of NCSA HDF5 library, so you need to dowload
prebuild HDF5 librariesI HDF5-1.6.4 library or higher. You also need zlib 1.2
and szlib 2.0. For windows user be sure to set the attributes writable
(especialy if you are using cygwin) and that the DLLs can be located
somewhere by your PATH environment variable.
You may also download source code NCSA HDF
Home Page (see links below).<p>
<h2>See Also:</h2>
<ul>
<li> Implemented as <tt>gdal/frmts/hdf5/hdf5dataset.cpp</tt>
and <tt>gdal/frmts/hdf5/hdf5imagedataset.cpp</tt>.<p>
<li> <a href="http://hdf.ncsa.uiuc.edu/HDF5/release/obtain5.html">The NCSA HDF5 Dowload Page</a>
at the
<a href="http://www.ncsa.uiuc.edu/">
National Center for Supercomputing Applications
</a>
<li> <a href="http://hdf.ncsa.uiuc.edu/hdf-java-html/hdfview/">The HDFView is a visual tool for browsing and editing NCSA HDF4 and HDF5 files.</a><p>
Documentation to individual products, supported by this driver:<p>
<ul>
<li> <a href="http://disc.gsfc.nasa.gov/Aura/OMI/omto3.shtml">
Aura OMI Total Ozone Data Product-OMTO3</a>
</ul>
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