NITFS
NITFS stands for the National Imagery Transmission Format Standard.
NITFS is designed to pack numerous image compositions with complete annotation, text attachments, and imagery-associated metadata.
Statistics and pyramid layers (.rrd files) are not created in export functions. These files are created when imported into IMAGINE, and the export function is used when this data is exported out of IMAGINE. If you need statistics and pyramid layers, please use the Image Command tool.
According to Jordan and Beck,
NITFS is an unclassified format that is based on ISO/IEC 12087-5, Basic Image Interchange Format (BIIF). The NITFS implementation of BIIF is documented in U.S. Military Standard 2500B, establishing a standard data format for digital imagery and imagery-related products.
NITFS was first introduced in 1990 and was for use by the government and intelligence agencies. NITFS is now the standard for military organizations as well as commercial industries.
Jordan and Beck list the following attributes of NITF files:
• provide a common basis for storage and digital interchange of images and associated data among existing and future systems
• support interoperability by simultaneously providing a data format for shared access applications while also serving as a standard message format for dissemination of images and associated data (text, symbols, labels) via digital communications
• require minimal preprocessing and post-processing of transmitted data
• support variable image sizes and resolution
• minimize formatting overhead, particularly for those users
transmitting only a small amount of data or with limited bandwidth
• provide universal features and functions without requiring commonality of hardware or proprietary software
Moreover, NITF files support the following:
• multiple images
• annotation on images
• ASCII text files to accompany imagery and annotation
• metadata to go with imagery, annotation and text
The process of translating NITFS files is a cross-translation process.
One system’s internal representation for the files and their associated data is processed and put into the NITF format. The receiving system reformats the NITF file, and converts it for the receiving systems internal representation of the files and associated data.
In ERDAS IMAGINE, the IMAGINE NITF™ software accepts such information and assembles it into one file in the standard NITF format.
Source: Jordan and Beck, 1999
Annotation Data
Annotation data can also be imported directly. Table 3: “Annotation Data Formats” lists the Annotation formats.There is a distinct difference between import and direct read. Import means that the data is converted from its original format into another format (for example, IMG, TIFF, or GRID Stack), which can be read directly by ERDAS IMAGINE. Direct read formats are those formats which the Viewer and many of its associated tools can read immediately without any conversion process.
Generic Binary Data
The Generic Binary import option is a flexible program which enables the user to define the data structure for ERDAS IMAGINE. This program allows the import of BIL, BIP, and BSQ data that are stored in left to right, top to bottom row order. Data formats from unsigned 1-bit up to 64-bit floating point can be imported. This program imports only the data file values—it does not import ephemeris data, such as georeferencing information. However, this ephemeris data can be viewed using the Data View option (from the Utility menu or the Import dialog).Table 3: Annotation Data Formats
Data Type Import Export Direct Read
Direct Write
Annotation (.ovr) • •
ANT (Erdas 7.x) • •
AOI (Area of Interest) (.aoi) • •
ASCII To Point Annotation •
DXF To Annotation •
Complex data cannot be imported using this program; however, they can be imported as two real images and then combined into one complex image using the Spatial Modeler.
You cannot import tiled or compressed data using the Generic Binary import option.
Vector Data
Vector layers can be created within ERDAS IMAGINE by digitizing points, lines, and polygons using a digitizing tablet or the computer screen. Several vector data types, which are available from a variety of government agencies and private companies, can also be imported.Table 4: “Vector Data Formats” lists some of the vector data formats that can be imported to, and exported from, ERDAS IMAGINE:
There is a distinct difference between import and direct read.
Import means that the data is converted from its original format into another format (for example, IMG, TIFF, or GRID Stack), which can be read directly by ERDAS IMAGINE. Direct read formats are those formats which the Viewer and many of its associated tools can read immediately without any conversion process.
Table 4: Vector Data Formats
Data Type Import Export Direct Read
Direct Write
ARCGEN • •
ArcGIS Geodatabase (.gbd) •
Arc Interchange • •
Arc_Interchange to Coverage
•
Arc_Interchange to Grid • ASCII To Point Coverage •
Coverage to DXF •
Coverage to Arc_Interchange
•
DFAD • •
DGN (Intergraph IGDS) • DIG Files (Erdas 7.x) •
Once imported, the vector data are automatically converted to ERDAS IMAGINE vector layers.
These vector formats are discussed in more detail in Vector Data from Other Software Vendors on page 138. See "Vector Data"
on page 41 for more information on ERDAS IMAGINE vector layers.
Import and export vector data with the Import/Export function. You can also convert vector layers to raster format, and vice versa, with the IMAGINE Vector utilities.
DLG • •
DXF to Annotation •
DXF to Coverage •
ETAK •
IGDS (Intergraph .dgn File) •
IGES • •
MIF/MID (MapInfo) to Coverage
•
ORACLE Spatial Feature (.ogv)
•
SDE • •
SDTS • •
Shapefile • •
Terramodel •
TIGER • •
VirtualGIS TIN Mesh •
VirtualGIS TIN World •
VPF • •
Table 4: Vector Data Formats
Data Type Import Export Direct Read
Direct Write