Licensing options for this format begin with FME Desktop Professional Edition.
The NITF Reader/Writer module provides FME with access to data in the National Imagery Transmission Format (NITF) standard.
Overview
The National Imagery Transmission Format (NITF) standard is composed of an image accompanied by subimages, symbols, labels, text, and other information that relates to the image. One of the main features of the NITF is that it allows several items of each data type to be included in one file, yet any data types may be omitted.
The NITF Reader supports reading of several subtypes of NITF image files, including NITF 1.1, NITF 2.0 and NITF 2.1/NSIF 1.0 files with uncompressed or VQ compressed images.
Color tables for pseudocolored images are read. In some cases, NoData values may be identified. Lat/Long extents are read from the IGEOLO information in the image header if available. Other coordinates systems (such as MGRS) are ignored at this time.
The NITF Writer supports writing files georeferenced and non georeferenced files with classified or continuous data. Files are always written in the uncompressed NITF 2.1 format.
GCPs (ground control points) present along with a projection in an NITF file being read can either be applied to the data as an affine transformation, or stored as properties on the raster geometry. GCPs cannot be written to NITF.
Reader Overview
FME considers a single NITF file to be a dataset. The NITF file contains pixel data. Each pixel in the file is a point in a single FME raster feature.
Writer Overview
FME considers a dataset to be a folder name. The names of the NITF output files written to the output dataset folder are determined from the fme_raster_filename attribute or from the FME Feature Type. The destination folder does not have to exist before the translation occurs. Any existing files in the folder which have the same name are overwritten with the new feature data.
The NITF writer distinguishes duplicate output files by appending numbers to the filenames.
At this time, writing georeferenced NITF files can be done only using Latitude/Longitude and Universal Transverse Mercator (UTM) projections with the WGS-1984 datum. If the source data does not contain information satisfying these criteria, FME will automatically try to reproject the data before writing the file. If this reprojection fails or if the source data is not georeferenced, the destination file will not be georeferenced.
FME Raster Features
FME raster features represent raster data and use several concepts that are unlike those used in the handling of vector data. The topics below describe how FME processes raster data.
NITF supports rasters with up to nine bands, provided all bands are the same data type. When this data type is UInt8, any number of bands may have a palette.