|High Resolution Elevation
|.hr1, .hr2, .hr3, .hr4, .hr5, .hr6, .hr7, .hr8. .hrz
National Geospatial-Intelligence Agency (NGA)
Data product name and description
|HREGP data is cast on a geographic projection and primarily covers large geospatial areas (nominally region-sized). HREGP products are typically tiled to allow them to be joined into these large area configurations. The HREGP data set's horizontal and vertical values are horizontally and vertically coincident at the data set edges. That is, the adjacent HREGP product coincident points' horizontal coordinates and vertical elevation values will be the same.
|HRE80-HRE01 data is cast on the Universal Transverse Mercator (UTM) projection and primarily cover localized area data set extents. HRE80-HRE01 data sets are designed to be spatially contained within a single UTM zone. Adjacent data sets within one UTM zone are horizontally coincident at the data set edge, but adjacent data sets in adjacent UTM zones are not horizontally coincident at the data set edge. Vertical elevation values may (but are not required to) match across HRE80-HRE01 levels for the same geographic area or elevation point.
|Each HRE NITF 2.1 file contains:
File naming convention
The following naming convention will be used for the identification of the High Resolution Elevation (HRE) product files:
The file name convention is defined as follows:
For projections, the rr value will be "GP" for Geographic Unprojected Position.
For resolution, the rr value will be the truncated decimeter value of the post-spacing. This value will be from the enumerated list: 80, 40, 20, 10, 05, 02, or 01.
A = optical source, unedited reflective surface
B = optical source, edited reflective surface
C = optical source, edited bare earth surface
D = reserved for future use
E = reserved for future use
F = IFSAR source, unedited reflective surface
G = IFSAR source, edited reflective surface
H = IFSAR source, edited bare Earth surface
I = reserved for future use
J = reserved for future use
K = LIDAR source, unedited first return
L = LIDAR source, unedited last return
M= LIDAR source, unedited bare Earth
N = LIDAR source, edited first return
O = LIDAR source, edited last return
P = LIDAR source, edited bare Earth
Q = reserved for future use
R = reserved for future use
S = reserved for future use
T = SAR source, unedited reflective surface
U = SAR source, edited reflective surface
V = SAR source, edited bare Earth
W = reserved for future use
X = unidentified source, reflective surface
Y = unidentified source, bare Earth surface
Z = Reserved for future use
DDMMSShDDMMSSe = South-West corner of DEM
DDMMSS = Latitude Degree, Minute, Second, from 90 to -90
h = hemisphere (N for North, S for South)
DDDMMSS = Longitude Degree, Minute, Second, from 180 to -180
e = direction (E for East, W for West)
Important notes to the user:
EASI> fili = path/filename.ext:NITF:Raster:1
|DTEM post-height data
|One raster channel (data type is 32-bit real)
|GDB retrieves DTEM post-height data as a raster channel. The data is stored as 32-bit real numbers. GDB also retrieves the image subheader information as its associated metadata.
|Region by post data(optional)
|One raster channel (data type is 8-bit integer)
|This image segment is comprised of the image subheader information and rigorous error propagation post-by-post region definition data. This is an optional image segment, as the regions may also be defined by specifying polygon boundaries in the XML Data Content Data Extension Segment (DES).
|Random error scale factors by post data (optional)
|One raster (data type is 32-bit real)
|This image segment is comprised of the image subheader information and random error scale factors by post data. These scale factors are used in conjunction with region-by-region nominal random error covariance matrices defined in the XML Data Content Data Extension Segment (DES).
|Random error covar by post data (optional)
|Three raster channels
|This image segment is comprised of the image subheader information and the random error covariance by post data. The random error covariance data is input as standard deviation terms that when squared, make up the diagonal terms of the random error covariance matrices.
|Random correlation coefs by post data (optional)
|Three raster channels
|This image segment is comprised of the image subheader information and random error correlation coefficients by post data. The random error correlation coefficient data (when multiplied by the corresponding diagonal term standard deviations) makes up the off-diagonal terms of the random error covariance matrices.
|General information and metadata
|Metadata associated with the DTEM data is contained in the XML Data Content Data Extension Segment (XML_DATA_CONTENT DES). A single XML_DATA_CONTENT DES is included in every NITF-formatted HRE data file. This data extension segment is comprised of subheader information and XML-formatted metadata.
File-level metadata includes three parts: NITF file header metadata, XML Data Content Segment metadata, and extended header data (Profile for Imagery Access Product Support Extension data).
The following are the main file-level metadata tags that are returned:
|File profile name
|The title of the file
HRE High Resolution Elevation Data
|US National Geospatial-Intelligence Agency
File security classification system
|Use country codes as defined in FIPS PUB 10-4 to indicate national security systems.
|Standard type or capability
|BF01 (indicates that this file is formatted using ISO/IEC IS 12087-5)
|Originating station ID
|Identification code or name of the originating organization, system, station, or product
|File control and handling
|Valid additional security control and/or handling instructions (caveats) associated with the file
|Unique identifier for this metadata file
|File name of the NITF file (or separate metadata file) that contains the metadata
|Language used for documenting metadata
|Full name of the character coding standard used for the metadata set
|Name of the responsible organization
|Date that the metadata was created
|Name of the metadata standard (including profile name) used
|ISO 19115 Geographic Information – Metadata
|Uniform Resource Identifier (URI) of the data set to which the metadata applies
|Character string of the form "urn:nga-hre: filename"
|Alphanumeric value identifying one of the horizontal reference systems specified in this implementation profile
|Name by which the cited resource is known
|File name of the NITF file that contains the elevation data. See the above explanation of file naming conventions. Use the HRE naming scheme here.
|Description of the attribute described by the measurement value
|A paired value (name, data type). For example: digitalSurfaceModel, Real
|“00”, indicating zero repeating SECTITLE values
The format for any rigorous error image segments included will follow the same format pattern, with the first three letters changed to one of the following identification tags:
|The date or the date and time that the product was created or last modified, expressed in ZULU time
|Product short name
|The abbreviated name of a product stored in the archive
The following are the main metadata tags for individual rasters that are returned:
|File part type
|Field containing the characters “IM” to identify the subheader as an image subheader
|Actual bits-per-pixel per band
|Field containing the number of significant bits for the value in each band of each pixel without compression
|MATR (indicates Matrix Data)
|Number of bands
|Field containing the number of data bands within the specified image
|Number of significant columns in image
|Field containing the total number of columns of significant pixels in the image
|Number of significant rows in image
|Field containing the total number of rows of significant pixels in the image
|Field containing a description of the source of the image
|NODISPLY (indicates data not intended for display)
|File part type
|Field containing the characters "DE" to identify the subheader as a data extension
|Unique DES type identifier
|Field containing the following string: XML_DATA_CONTENT
|XML file type
|Field containing data that is representative of the XML file type
|DES user-defined subheader length
|Field containing the number of bytes in the DESSHF field
|User-defined data field
|Field containing the XML data. The length of this field will not cause any other NITF field length limits to be exceeded, but is otherwise fully user-defined.
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