=============================================================================== AVIRIS-3 Distribution Document =============================================================================== Michael Eastwood, meastwood@jpl.nasa.gov Sarah R. Lundeen, Sarah.R.Lundeen@jpl.nasa.gov Robert O. Green, Robert.O.Green@jpl.nasa.gov David R. Thompson, David.R.Thompson@jpl.nasa.gov John W. Chapman, John.W.Chapman@jpl.nasa.gov Adam M. Chlus, Adam.M.Chlus@jpl.nasa.gov This document describes the AVIRIS-3 L1 and L2 data products. AVIRIS-3 is an imaging spectrometer that measures reflected radiance at 7.5nm intervals in the Visible to Shortwave Infrared (VSWIR) spectral range from 390-2510nm. ------------------------------------------------------------------------------- OVERVIEW ------------------------------------------------------------------------------- Each flightline uses a specific base filename prefix: AV3YYYYMMDDtHHNNSS YYYY: The year of the airborne flight run. MM: The month of the airborne flight run (i.e. 05 represents May). DD: The day of the airborne flight run (22 is the 22nd day of the month) HH: UTC hour at the start of acquisition NN: UTC minute at the start of acquisition SS: UTC second at the start of acquisition Each flightline name also includes a software processing version/tag and a parameter hash: VVV_PPPPPPPP VVV: Tag/version of product generation executable (PGE) used to generate data product. PPPPPPPP: Unique 8-digit truncated SHA-256 hash generated using input parameters and files. The AVIRIS-3 data products for a particular airborne flight run are organized in the following directory structure: /YYYYMMDDtHHNNSS_VVV | AV3YYYYMMDDtHHNNSS_L1B_RDN_VVV_PPPPPPPP_RDN_ORT | AV3YYYYMMDDtHHNNSS_L1B_RDN_VVV_PPPPPPPP_RDN_ORT.hdr | AV3YYYYMMDDtHHNNSS_L1B_ORT_VVV_PPPPPPPP_GLT | AV3YYYYMMDDtHHNNSS_L1B_ORT_VVV_PPPPPPPP_GLT.hdr | AV3YYYYMMDDtHHNNSS_L1B_ORT_VVV_PPPPPPPP_IGM | AV3YYYYMMDDtHHNNSS_L1B_ORT_VVV_PPPPPPPP_IGM.hdr | AV3YYYYMMDDtHHNNSS_L1B_ORT_VVV_PPPPPPPP_LOC_ORT | AV3YYYYMMDDtHHNNSS_L1B_ORT_VVV_PPPPPPPP_LOC_ORT.hdr | AV3YYYYMMDDtHHNNSS_L1B_ORT_VVV_PPPPPPPP_OBS_ORT | AV3YYYYMMDDtHHNNSS_L1B_ORT_VVV_PPPPPPPP_OBS_ORT.hdr | AV3YYYYMMDDtHHNNSS_L2A_OE_VVV_PPPPPPPP_RFL_ORT | AV3YYYYMMDDtHHNNSS_L2A_OE_VVV_PPPPPPPP_RFL_ORT.hdr | AV3YYYYMMDDtHHNNSS_L2A_OE_VVV_PPPPPPPP_UNC_ORT | AV3YYYYMMDDtHHNNSS_L2A_OE_VVV_PPPPPPPP_UNC_ORT.hdr The file product codes signify: *OBS_ORT parameters relating to the geometry of observation and illumination rendered using the *_ort_glt lookup table. *OBS_ORT.hdr obs_ort image header file. *GLT geometric look-up table. *GLT.hdr GLT image header file. *IGM input geometry file. *IGM.hdr IGM image header file. *RDN_ORT orthocorrected radiance image file. *RDN_ORT.hdr radiance image header file. *RFL_ORT orthocorrected reflectance image file. *RFL_ORT.hdr reflectance image header file. *UNC_ORT orthocorrected reflectance uncertainty image file. *UNC_ORT.hdr uncertainty image header file. ------------------------------------------------------------------------------ FILE DESCRIPTIONS ------------------------------------------------------------------------------ *GLT GEOMETRIC LOOKUP TABLE (GLT) Contents: Orthocorrected product with a fixed pixel size projected into a rotated UTM system that contains the information about which original pixel occupies which output pixel in the final product. Additionally, each pixel is sign-coded to indicate if it is real (indicated by a positive value) or a nearest-neighbor infill (indicated by negative values). The GLT file contains two parameters: 1) sample number 2) original line number File type: BINARY 16-bit, integer, IEEE. Format: Band interleaved by line ------------------------------------------------------------------------------ *GLT.hdr HEADER FILE FOR GEOMETRIC LOOKUP TABLE (GLT.HDR) DATA Contents: Format of each *GLT file. This file contains the number of lines, samples, channel, integer format, pixel size, scene elevation, UTM zone number and rotation angle information, etc. File type: ASCII ------------------------------------------------------------------------------- *IGM INPUT GEOMETRY FILE (IGM) Contents: Pixel location data for each radiance image cube. The IGM file data contain three parameters: 1) WGS-84 longitude (reported in decimal degrees) 2) WGS-84 latitude (reported in decimal degrees) 3) Estimated ground elevation at each pixel center (reported in meters) No map correction or resampling is applied to the radiance image cube; the IGM file only reports the surface location of the unadjusted pixel centers. File type: BINARY 64-bit double precision, floating point IEEE. Units: Band 1 - decimal degrees Band 2 - decimal degrees Band 3 - meters Format: Band interleaved by line ---------------------------------------------------------------------------- *IGM.hdr HEADER FILE FOR INPUT GEOMETRY FILE (IGM) DATA Contents: Format of each *ort_igm file. This file contains the number of lines, samples, channel, integer format, etc. File type: ASCII ---------------------------------------------------------------------------- *RDN_ORT CALIBRATED AVIRIS-3 RADIANCE (IMAGE) DATA Contents: AVIRIS-3 calibrated radiance File type: BINARY 32-bit little-endian floating point IEEE. Units: microwatts per centimeter_squared per nanometer per steradian Format: Band interleaved by line -------------------------------------------------------------------------------- *RDN_ORT.hdr HEADER FILE FOR CALIBRATED AVIRIS-3 RADIANCE (IMAGE) DATA Contents: Format of each AVIRIS-3 calibrated radiance scene. This file contains the number of lines, samples, channel, etc. It also records the spectral calibration (wavelength and full-width at half-maximum value) for every channel in the radiance data. File type: ASCII ---------------------------------------------------------------------------- *RFL_ORT CALIBRATED AVIRIS-3 REFLECTANCE (IMAGE) DATA Contents: AVIRIS-3 surface reflectance File type: BINARY 32-bit little-endian floating point IEEE. Units: Apparent surface reflectance (Thompson et al., 2018, Thompson et al., 2019, Thompson et al., 2020) Format: Band interleaved by line -------------------------------------------------------------------------------- *RFL_ORT.hdr HEADER FILE FOR CALIBRATED AVIRIS-3 REFLECTANCE (IMAGE) DATA Contents: Format of each AVIRIS-3 calibrated reflectance scene. This file contains the number of lines, samples, channel, etc. It also records the spectral calibration (wavelength and full-width at half-maximum values) for every channel in the reflectance data. File type: ASCII ---------------------------------------------------------------------------- *UNC_ORT CALIBRATED AVIRIS-3 REFLECTANCE UNCERTAINTY (IMAGE) DATA Contents: AVIRIS-3 surface reflectance uncertainty File type: BINARY 32-bit little-endian floating point IEEE. Units: Apparent surface reflectance (Thompson et al., 2018, Thompson et al., 2019, Thompson et al., 2020) Format: Band interleaved by line -------------------------------------------------------------------------------- *UNC_ORT.hdr HEADER FILE FOR CALIBRATED AVIRIS-3 REFLECTANCE UNCERTAINTY (IMAGE) DATA Contents: Format of each AVIRIS-3 calibrated reflectance uncertainty scene. This file contains the number of lines, samples, channel, etc. It also records the spectral calibration (wavelength and full-width at half-maximum values) for every channel in the uncertainty data. File type: ASCII ---------------------------------------------------------------------------- *.yaml DATA PRODUCT METADATA Contents: Contains metadata for each data product including input files and PGE parameters. File type: YAML File type: ASCII -------------------------------------------------------------------------------- REFERENCES -------------------------------------------------------------------------------- D. R. Thompson, V. Natraj, R. O. Green, M. C. Helmlinger, B. C. Gao, M. L. Eastwood, Optimal estimation for imaging spectrometer atmospheric correction, Remote Sens. Env., 216, 355-373, 2018. D. R. Thompson, K.N. Babu, A. J. Braverman, M. L. Eastwood, R. O. Green, J. M. Hobbs, J. B. Jewell, B. Kindel, S. Massie, M. Mishra, A. Mathur, V. Natraj, P. A. Townsend, F. C. Seidel, M. J. Turmon, Optimal estimation of spectral surface reflectance in challenging atmospheres, Remote Sens. Env., 232, 111258, 2019. D. R. Thompson, A. Braverman, P. G. Brodrick, A. Candela, N. Carmon, R. N. Clark, D. Connelly, R. O. Green, R. F. Kokaly, L. Li, N. Mahowald, R. L. Miller, G. S. Okin, T. H. Painter, G. A. Swayze, M. Turmon, J. Susilouto, D. S. Wettergreen, Quantifying uncertainty for remote spectroscopy of surface composition, Remote Sens. Env., 247, 111898, 2020. -------------------------------------------------------------------------------- ACKNOWLEDGEMENTS -------------------------------------------------------------------------------- This research was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration (NASA). We are grateful for the help and assistance of colleagues including Bo-Cai Gao (NRL), Ian McCubbin (JPL), Dar Roberts (UCSB), Mark Helmlinger (JPL), Scott Nolte (JPL), Ernie Diaz (JPL), Daniel Nunes (JPL), and the rest of the AVIRIS-3 team. Copyright 2016 California Institute of Technology. All Rights Reserved. U.S. Government Support Acknowledged. -------------------------------------------------------------------------------- MODIFICATIONS -------------------------------------------------------------------------------- 6 Feb . 2016 (D. R. Thompson) - Minor updates, translated back to AVIRIS-3 21 Sept. 2014 (D. R. Thompson) - Translated from AVIRIS-3 to PRISM 10 Sept. 2014 (D. R. Thompson) - Initial document