Image Navigation Record - GOES Satellite Hunt

Image Navigation Record

This header is one of the most interesting things you can get. It is used to map a specific pixel to a coordinate (latitude / longitude) in the image (and vice-versa). This header is not mandatory on any of the images, and some satellite relays doesn’t include it. For example Himawari 8 relays over GOES-16 doesn’t include Navigation Record. Open Satellite Project uses this header to generate Map Overlays and to define the coordinate of the center of the image (useful for non full disk scans).

Name Type Description
Projection Name string ( 32 ) The name of the Image Projection
Column Scaling Factor uint32_t The Scaling Factor for each column
Line Scaling Factor uint32_t The Scaling Factor for each line
Column Offset uint32_t The Offset for Columns
Line Offset uint32_t The Offset for Lines

Table 7 - Image Navigation Record Fields

For calculation of the Lat/Lon Coordinates a mathematical model described in CGMS 03 - LRIT/HRIT Global Specification (page 20) should be used. A pratical implementation can be found on Open Satellite Project GeoTools Class.