========================================================================= AVIRIS Distribution Document 030217 SEND COMMENTS TO rog@jpl.nasa.gov Additional informatin may be found on http://aviris.jpl.nasa.gov -------------------------------------------------------------------------- All distibuted files are in a tar file. The following types of files should be found: PER FLIGHT LINE (i.e., occurs once per tar file/tape): *.info general information about the flight line, *.gain multiplication factors, radiance to 16-bit integer, *.geo geometric calibration data, *.eng engineering data, *.nav navigation data, *.rcc radiometric calibration coefficients, *.readme this file, *.spc spectral calibration file. *.glt geometric look up table *.glt.hdr geometric look up t *.igm input geometry file *.igm.hdr input geometry file header PER SCENE (i.e., occurs once or several times per tar file/tape): *.img calibrated AVIRIS radiance (image) data, *.img.hdr image format of the scene To list files (table-of-contents): tar tvf "tar file name" (on disc), tar tvf "device name" (on tape). To extract files: tar xvf "tar file name" "extract file name" (on disc), tar xvf "device name" "extract file name" (on tape). To get information about tar: man tar ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- PER FLIGHT LINE ---------------------------------------------------------------------------- *.info GENERAL INFORMATION ABOUT THE FLIGHT LINE File type: ASCII. Information about the acquisition of the AVIRIS data. ---------------------------------------------------------------------------- *.gain MULTIPLICATION FACTORS, RADIANCE TO 16-BIT INTEGER Contents: Multiplication factors to store radiance as 16-bit integers. File type: ASCII. Units: none. Format: Two columns: - Multiplication factor, - Channel number. Use: When each spectrum is divided by the factors in this file the 16-bit integers are converted to radiance in units of (micro- watts/cm^2/nm/sr). ---------------------------------------------------------------------------- *.geo GEOMETRIC CALIBRATION DATA Contents: AVIRIS' spatial resolution on the ground. File type: ASCII. Format: Five columns: - Spatial sampling interval (pixel center to center distance on the ground, in milliradians), - Spatial response function (the FWHM (in milli- radians) of the spatial response function (assumed to be Gaussian); this is a measure of the nominal pixel size), - Spatial sampling interval uncertainty (in milli- radians), - Spatial response function uncertainty (in milli- radians), - Channel number. ---------------------------------------------------------------------------- *.rcc RADIOMETRIC CALIBRATION COEFFICIENTS Contents: AVIRIS radiometric calibration coefficients and laboratory calibration uncertainty. File type: ASCII. Units: microwatts per centimeter_squared per nanometer per steradian per digitized_number. Format: Three columns: - Radiometric calibration coefficent, - Uncertainty in radiometric calibration coeff., - Channel number. ---------------------------------------------------------------------------- *.readme THIS FILE File type: ASCII. ---------------------------------------------------------------------------- *.spc SPECTRAL CALIBRATION FILE Contents: AVIRIS spectral calibration. File type: ASCII. Units: nanometers. Format: Five columns: - Wavelength center position, - Full width at half maximum for equivalent gaussian, - Uncertainty in wavelength center position, - Uncertainty in FWHM for equivalent gaussian, - Channel number. ---------------------------------------------------------------------------- *.eng ENGINEERING DATA File type: ASCII This file contains the recorded engineering data ---------------------------------------------------------------------------- *.nav NAVIGATION DATA File type: ASCII. This file contains the recorded AVIRIS navigation data. ---------------------------------------------------------------------------- *.igm INPUT GEOMETRY FILE File type: Binary Contents: Band 1 contain determined UTM Easting for each spatial element in the original image. Band 2 contains the UTM Northing. ---------------------------------------------------------------------------- *.igm.hdr HEADER FILE FOR THE INPUT GEOMETRY FILE File type: ASCII Contents: File format description for the *.igm file. ---------------------------------------------------------------------------- *.glt GEOMETRIC LOOK UP TABLE File type: Binary Contents: Band 1 original sample number for the georectified image location. Band 2 original line number for the georectified image location. A negative value indicates the georectified value has been nearest neighbor interpolated ---------------------------------------------------------------------------- *.glt.hdr HEADER FILE FOR THE GEOMETRIC LOOK UP TABLE File type: ASCII Contents: File format description for the *.glt file. ========================================================================= PER SCENE (2048 AVIRIS lines of data) ---------------------------------------------------------------------------- *.img CALIBRATED AVIRIS RADIANCE (IMAGE) DATA Contents: AVIRIS calibrated radiance multipled by the gain and stored as 16-bit integers. File type: BINARY 16-bit signed integer IEEE. Units: gain times (microwatts per centimeter_squared per nanometer per steradian). Format: Band interleaved by pixel (channel, sample, line) with dimensions (224, ns, nl). -------------------------------------------------------------------------------- *.img.hdr HEADER FILE FOR CALIBRATED AVIRIS RADIANCE (IMAGE) DATA Contents: Format of each AVIRIS calibrated radiance scene. This file contains the number of lines, samples, channel, integer format, etc. File type: ASCII ========================================================================= KNOWN ARTIFACTS 1) There is a slew effect in the AVIRIS detector array readout. Slew expresses itself as a slight shift in the IFOV when moving from regions of very different brightnesses. 2) In 2002, the bad detector at channel 77 has been interpolated. =========================================================================