TREs contain information that cannot be stored in the NITF file header or segment subheaders. One or more TREs that apply to the entire NITF dataset can be present in the file header, and each segment (image or text) can also have one or more TREs associated with it. In some cases, TREs are applied to the data in a file or segment to enhance the utility of the data. Unless there is a large amount of data in a TRE, the TRE data is stored in the main header or segment subheader to which the TRE applies. For TREs too large to fit in the segment TRE area, a Data Extension Segment (DES) is created at the end of the file, and a pointer to this DES is stored within the header.

TREs come in two forms: Registered Extensions (REs) and Controlled Extensions (CEs). The NITF Standard Technical Board (NTB) maintains a registry of known CEs and REs: the main difference is that both the TRE name and TRE layout of CEs are controlled by the NTB, whereas only the TRE names of REs are registered with the NTB to prevent different users from using the same TRE name. Therefore, CEs can be interpreted based on the published information contained in the NTB repository, whereas REs require specific knowledge of the TRE contents available to the creator of the TRE that may not be available to the data consumer.

An example of a TRE is the RPC00B (Rapid Positioning Capability) TRE that can be associated with an image segment in a NITF dataset. This TRE provides coefficients that can be used to orthorectify the associated image segment. Other Controlled Extension TREs specify processing history, information about specific targets in an image, collection information, and other types of metadata.

The repository of Controlled Extension and Registered Extension TREs can be viewed online at the JITC web site.

For information on classified TREs, please visit our Request Technical Support web page.

Supported TREs

There are two levels of TRE support in the NITF Module:

  • Unsupported TREs: TREs for which no definition is available, or the definition does not match the physical layout of the TRE. Only the raw data of TREs of this type can be viewed.
  • Supported TREs: TREs that match a valid TRE definition. The data in these TREs can be read and written. The data in these TREs can be viewed with the appropriate header information in the View Metadata dialog. These TREs may be parsed into their specific components, and the value associated with each field in the TRE is displayed in the View Metadata dialog. To view the information contained in this type of TRE, open the TRE container. Each field in the TRE is displayed as a single entry.

The data in these TREs can be written into file, image, and text segments of new NITF files. When saving to NITF, you can view these TREs in the View Metadata dialog. Although the supported TREs for writing data can be displayed in the editor, only PIA TREs can be added, edited, or removed from their associated file header, image or text segment.

Each supported TRE references an XML definition file. Definition files for a partial list of the NTB-registered CEs are installed with ENVI. Support for TREs can be added by creating TRE definitions for the desired TREs. For more information about these TREs, contact Technical Support.

When opening a NITF image, ENVI does not parse the TRE fields if there is no corresponding XML definition file. When writing a NITF file that contains a TRE with no corresponding XML file, ENVI passes through this unknown TRE.

The following table describes TREs that ENVI currently supports for reading and writing data. The Reference column lists the applicable NITF specification document.

  • BPJ2K01: BIIF Profile for JPEG 2000

  • MIL-PRF-89034: Digital Point Positioning Data Base (DPPDB)

  • NGA.STND.0044_1.3_MIE4NITF: Standard for MIE4NITF

  • NSGPDD: National System for Geospatial Intelligence Product Definition Document
  • RSM: Replacement Sensor Model Tagged Record Extensions Specification for NITF 2.1

  • STDI-0002: The Compendium of Controlled Extensions for NITF version 2.1

  • STDI-0006: National Transmission Format (NITF) Version 2.1 Commercial Dataset Requirements Document (NCDRD)

TRE/DES Name

Filename

Descriptive Name

Reference

ACCHZB

ACCHZB.xml

Horizontal Accuracy Extension

STDI-0002

ACCPOB

ACCPOB.xml

Positional Accuracy Extension

STDI-0002

ACCVTB

ACCVTB.xml

Vertical Accuracy Extension

STDI-0002

ACFTA

ACFTA.xml

Aircraft Information Version A

STDI-0002

ACFTB

ACFTB.xml

Aircraft Information Version B

STDI-0002

AIMIDA

AIMIDA.xml

Additional Image Identification Version A

STDI-0002

AIMIDB

AIMIDB.xml

Additional Image Identification Version B

STDI-0002

BANDSA

BANDSA.xml

Multispectral/ Hyperspectral Band Parameters

STDI-0002

BANDSB

BANDSB.xml

Extended Multispectral/Hyperspectral Band Parameters

STDI-0002

BCKGDA

BCKGDA.xml

Background Data

STDI-0002

BLOCKA

BLOCKA.xml

Image Block Information

STDI-0002

BNDPLB

BNDPLB.xml

Bounding Polygon

STDI-0002

CAMSDA

CAMSDA.xml

Camera Set Definition, Version A

NGA.STND.0044_1.3_MIE4NITF

CCINFA

CCINFA.xml

Country Code Information, Version A

STDI-0002

CMETAA

CMETAA.xml
CSATTA_DES_DESDATA.xml

Complex Metadata Tagged Record Extension Version A

STDI-0002

CSATTA_DES

CSATTA_DES.xml

Commercial Source Attitude Data, Version A

STDI-0002

CSATTB

CSATTB.xml
CSSATTB_DESDATA.xml

Common Sensor Attitude Data

NSGPDD

CSCCGA

CSCCGA.xml

Cloud Cover Grid

STDI-0006

CSCRNA

CSCRNA.xml

Corner Footprint

STDI-0006

CSCSDB

CSCSDB.xml
CSCSDB_DESDATA.xml

Common Sensor Covariance Support Data

NSGPDD

CSDIDA

CSDIDA.xml

Dataset Identification

STDI-0006

CSEPHA

CSEPHA.xml

Ephemeris Data

STDI-0006

CSEPHB

CSEPHB.xml
CSEPHB_DESDATA.xml

Common Sensor Ephemeris Data

STDI-0002

CSEXRA

CSEXRA.xml

Exploitation Reference Data

STDI-0006

CSEXRB

CSEXRB.xml

Common Sensor Exploitation Reference Data

STDI-0002

CSPROA

CSPROA.xml

Processing Information

STDI-0006

CSRLSB

CSRLSB.xml

Common Sensor Rolling Shutter Terms

STDI-0002

CSSFAA

CSSFAA.xml

Sensor Field Alignment Data

STDI-0006

CSSFAB

CSSFAB.xml
CSSFAB_DESDATA.xml

Common Sensor Field Alignment Data

STDI-0002

CSSHPA

CSSHPA_DES.xml

Common Sensor Shapefile

STDI-0006

CSSHPB

CSSHPB.xml
CSSHPB_DES.xml

Common Sensor Shapefile

NSGPDD

CSWRPB

CSWRPB.xml

Common Sensor Warping Terms

STDI-0002

ENGRDA

ENGRDA.xml

Engineering Data

STDI-0002

EXOPTA

EXOPTA.xml

Exploitation Usability Optical Information

STDI-0002

EXPLTA

EXPLTA.xml

Exploitation Related Information Version A

STDI-0002

EXPLTB

EXPLTB.xml

Exploitation Related Information Version B

STDI-0002

EXT_DEF_CONTENT

EXT_DEF_CONTENT.xml

Externally defined content DES

STDI-0002

FASYWA

FASYWA.xml

Frame-Asynchronous Metadata Wrapper, Version A

STDI-0002

FCRNSA

FCRNSA.xml

File/Segment Corner Footprint

STDI-0002

FREESA

FREESA.xml

Free Space

NGA.STND.0044_1.3_MIE4NITF

FRMSGA

FRMSGA.xml

Framing Array Segment

STDI-0002

FSYNWA

FSYNWA.xml

Frame-Synchronous Metadata Wrapper, Version A

NGA.STND.0044_1.3_MIE4NITF

GEOLOB

GEOLOB.xml

Local Geographic (lat/long) Coordinate System Extension

STDI-0002

GEOPSB

GEOPSB.xml

Geographical Positioning for geo-referencing parameters including datum, ellipsoids

STDI-0002

GRDPSB

GRDPSB.xml

Grid Positioning Version B

STDI-0002

HISTOA

HISTOA.xml

Softcopy History Tagged Record Extension

STDI-0002

ICHIPA

ICHIPA.xml

Image Chip Support Data Extension Version A

STDI-0002

ICHIPB

ICHIPB.xml

Image Chip Support Data Extension Version B

STDI-0002

ILLUMA

ILLUMA.xml

Illumination, Version A

STDI-0002

ILLUMB

ILLUMB.xml

Illumination, Version B

STDI-0002

IMASDA

IMASDA.xml

Segment Image Support Data

MIL-PRF-89034

IMCBDA

IMCBDA.xml

Segment Image Compressed Blocks Directory

MIL-PRF-89034

IMRFCA

IMRFCA.xml

Segment Image Rational Function Coefficients

MIL-PRF-89034

IOMAPA

IOMAPA.xml

Input/Output Mapping Tagged Record Extension

STDI-0002

J2KLRA

J2KLRA.xml

JPEG 2000 Parameters

BPJ2K01

MAPLOB

MAPLOB.xml

Local Cartographic (x/y) Coordinate System Extension

STDI-0002

MATESA

MATESA.xml

Mates

STDI-0002

MENSRA

MENSRA.xml

Airborne SAR Mensuration Data Version A

STDI-0002

MENSRB

MENSRB.xml

Airborne SAR Mensuration Data Version B

STDI-0002

MIMCSA

MIMCSA.xml

Motion Imagery Collection Summary, Version A

NGA.STND.0044_1.3_MIE4NITF

MPDSRA

MPDSRA.xml

Mensuration Data

STDI-0002

MSDIRA

MSDIRA.xml

Master Product Directory Definition

MIL-PRF-89034

MSTGTA

MSTGTA.xml

Mission Target

STDI-0002

MTIMFA

MTIMFA.xml

Motion Imagery File, Version A

NGA.STND.0044_1.3_MIE4NITF

MTIMSA

MTIMSA.xml

Motion Imagery Segment, Version A

NGA.STND.0044_1.3_MIE4NITF

MTIRPA

MTIRPA.xml

Moving Target Information Report Version A

STDI-0002

MTIRPB

MTIRPB.xml

Moving Target Information Report Version B

STDI-0002

MTXFIL

MTXFIL.xml

MATRIX Fill

 

NBLOCA

NBLOCA.xml

(Number of Bytes) Image Block or Frame is Offset.

STDI-0002

OFFSET

OFFSET.xml

(NITF 2.1) Offset of the first pixel of an image from the first pixel of the full image.

STDI-0002

PATCHA

PATCHA.xml

Patch Information Version A

STDI-0002

PATCHB

PATCHB.xml

Patch Information Version B

STDI-0002

PIAEQA ** *

PIAEQA.xml

Profile for Imagery Archives Equipment

Profile for Imagery Access Equipment

STDI-0002

PIAEVA ** *

PIAEVA.xml

Profile for Imagery Archives Event

Profile for Imagery Access Event

STDI-0002

PIAIMB **

PIAIMB.xml

Profile for Imagery Archives Image

STDI-0002

PIAIMC *

PIAIMC.xml

Profile for Imagery Access Image

STDI-0002

PIAPEA **

PIAPEA.xml

Profile for Imagery Archives Person

STDI-0002

PIAPEB *

PIAPEB.xml

Profile for Imagery Access Person

STDI-0002

PIAPRC **

PIAPRC.xml

Profile for Imagery Archives Product

STDI-0002

PIAPRD *

PIAPRD.xml

Profile for Imagery Access Product

STDI-0002

PIATGA **

PIATGA.xml

Profile for Imagery Archives Target

STDI-0002

PIATGB *

PIATGB.xml

Profile for Imagery Access Target

STDI-0002

PIXMTA

PIXMTA.xml

Pixel Metrics, Version A

STDI-0002

PIXQLA

PIXQLA.xml

Pixel Quality

STDI-0002

PPRSDA

PPRSDA.xml

Product Accuracy (Shear) Data

MIL-PRF-89034

PRADAA

PRADAA.xml

Product Accuracy Data (Absolute) Definition

STDI-0002

PRADRA

PRADRA.xml

Product Accuracy Data (Relative) Definition

STDI-0002

PRJPSB

PRJPSB.xml

Projection Parameters Extension

STDI-0002

PSUPDA

PSUPDA.xml

Product Support Data

MIL-PRF-89034

PTPRAA

PTPRAA.xml

Segment to Segment Relative Accuracy

MIL-PRF-89034

REGPTB

REGPTB.xml

Registration Points Extension

STDI-0002

RGRDRA

RGRDRA.xml

Reference Graphic Directory Definition

MIL-PRF-89034

RPC00A

RPC00A.xml

Rapid Positioning Capability Support Data Extension

STDI-0002

RPC00B

RPC00B.xml

Rapid Positioning Capability Support Data Extension

STDI-0002

RSMAPA

RSMAPA.xml

RSM Adjustable Parameters

STDI-0002

RSMAPB

RSMAPB.xml

Replacement Sensor Model Adjustable Parameters

STDI-0002

RSMDCA

RSMDCA.xml

RSM Direct Error Covariance

STDI-0002

RSMDCB

RSMDCB.xml

Replacement Sensor Model Direct Error Covariance

STDI-0002

RSMECA

RSMECA.xml

RSM Error Covariance

STDI-0002

RSMECB

RSMECB.xml

Replacement Sensor Model Indirect Error Covariance

STDI-0002

RSMGGA

RSMGGA.xml

RSM Ground-to-image Grid

STDI-0002

RSMGIA

RSMGIA.xml

RSM Ground-to-image Grid Identification

STDI-0002

RSMIDA

RSMIDA.xml

RSM Identification

STDI-0002

RSMPCA

RSMPCA.xml

RSM Polynomial Coefficients

STDI-0002

RSMPIA

RSMPIA.xml

RSM Polynomial Identification

STDI-0002

SECTGA

SECTGA.xml

Secondary Target Information

STDI-0002

SEGSPA

SEGSPA.xml

Stereo Image Segment Shear Point Data

MIL-PRF-89034

SENSRA

SENSRA.xml

EO-IR Sensor Parameters

STDI-0002

SENSRB

SENSRB.xml

EO-IR Sensor Parameters

STDI-0002

SISDDA

SISDDA.xml

Stereo Image Segment Data

MIL-PRF-89034

SSDPDA

SSDPDA.xml

Stereo Image Segment Diagnostic Point Data

MIL-PRF-89034

STDIDC

STDIDC.xml

Standard ID Extension

STDI-0002

STREOA

STREOA.xml

Stereo Information

STDI-0002

STREOB

STREOB.xml

Stereo Information

STDI-0002

TMINTA

TMINTA.xml

Time Interval Definition, Version A

NGA.STND.0044_1.3_MIE4NITF

USE00A

USE00A.xml

Exploitation Usability Extension

STDI-0002

XML_DATA_CONTENT

XML_DATA_CONTENT.xml

XML data content DES

STDI-0002

* Indicates TREs that can be created, edited and deleted.

** Indicates TREs that can only be edited and deleted. These TREs cannot be added.