MIL-HDBK-1300 National Imagery Transmission Format Standard NitfsThis document describes the NITFS and its image and communications processing components. It provides general information regarding NITFS.

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MIL-HDBK-1300A

representation for files and data and the NITFS file format, NITF.  A system from which data are to be transferred is envisioned to have a translation module that accepts information structured according to the system's internal representation for images, text files, and other data and assembles this information together into one file in the standard NITF format.  The file will be transmitted to one or more recipients as a message using a user-chosen communication protocol.  NITFS specifies TAC02 for use in tactical communications.  The receiving systems will reformat the message, converting it into one or more files structured as required by the internal representation of the receiving station.  The functional architecture of this cross-translation process is shown on figure 4. In the diagram, the terms "Native1  Files" and "Native2  Files" refer to fields represented in a way potentially unique to the sending (system 1) or receiving (system 2) system, respectively.  Using the NITFS, each system must comply with all other participating systems.  The standard format allows a system to send data to several other systems with one transmission, since each receiving station converts the message into its own internally acceptable form.  Because each receiving station can translate selectively and permanently store only those portions of data in the received file that are of interest, a station may transmit all of its data in one message containing the one filed, even though some of the target systems may be unable to process certain elements of the data usefully.

FIGURE 4.  Functional architecture.

5.2.1.5  Format description.  The NITF is a byte oriented format.  All information, including numbers, contained in the NITF header and subheaders is given in the printable ASCII character set, with eight bits (one byte) per character.

5.2.1.6  Format structure.  Data transmitted using the NITF are preceded by the NITF header, which includes identification and descriptive information related to the file as a whole.  To ensure that all required data are provided to the end user, the NITF header and subheaders include data

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