Ibis Hyperspectral Sun-Induced Fluorescence Sensor

The Ibis sensor is a visible wave hyperspectral instrument manufactured by ​Specim. It has a spectral range from 670-780 nm in samples of 0.11 or 0.22 nm steps.

Raw data format

The Ibis data is captured as ENVI format BIL files (a pair of .hdr and .raw), with an associated nav file (usually one nav file per flight line). The .hdr files are ASCII text files where as the .raw and .nav are binary data files.

The Ibis .raw data files contain 12-bit data (values of 0-4095) stored as 16-bit integer for the VNIR data. At the end of the raw file, after data capture for this flight line, a number of lines of data are captured with the shutter closed. These lines are referred to as "dark lines" and give sensor ccd values for when no light is present.

The .nav files are a collection of different 'messages'. These contain the real-time position and attitude of the aircraft as well as periodic time stamps marking the start of the flight line capture.

Specifications for Ibis

Detector size	384x?
Bit depth (of sensor analog-to-digital converter)	12 bit VNIR, 16 bit SWIR
Spatial pixels	384
Spectral pixels	?
Spectral sampling	0.11 nm
Nominal spectral range (prior to calibration)	670-780 nm
Central pixel number	192
Field of View (FOV)	32.3 degrees