This tutorial presents a case history for use of hyperspectral techniques for vegetation analysis using 1997 AVIRIS data from Jasper Ridge, California, USA. It is designed to be a self-directed example using ENVI's complete end-to-end hyperspectral tools to produce image-derived endmember spectra and image maps. For more detail and step-by-step procedures on performing such a hyperspectral analysis, please execute tutorials 7-11 in this booklet prior to attempting this tutorial.
1) To examine application of ENVI end-to-end hyperspectral processing methodology to a vegetation case study
2) To give students hands-on experience in actually running the procedures rather than reviewing pre-calculated results (preprocessed results are provided for comparison)
3) To provide students with guidance to perform data exploration in a loosely structured framework
4) To compare analysis results with known ground information.
You must have the ENVI TUTORIALS & DATA CD-ROM mounted on your system to access the files used by this tutorial, or copy the files to your disk.
The files used in this tutorial are contained in the J97AVSUB subdirectory of the ENVIDATA directory on the ENVI TUTORIALS & DATA CD-ROM.
The files listed below are required to run this exercise. Miscellaneous files listed below provide additional information that may be useful. Selected data files have been converted to integer format by multiplying the reflectance values by 1000 because of disk space considerations. Values of 1000 in the files represent reflectance values of 1.0.
USGS_VEG.SLI USGS Vegetation Spectral Library
USGS_VEG.HDR ENVI Header for Above
USGS_MIN.SLI USGS Mineral Spectral Library
USGS_MIN.HDR ENVI Header for Above
VEG_2GRN.SL Jasper Ridge, Spectral Library
VEG_2GRN.HDR ENVI Header for Above
J97RDSUB.BIL JPL AVIRIS Radiance, 300 x 250 x 224 bands
J97RDSUB.HDR ENVI Header for Above
J97ATSUB.BIL AVIRIS ATREM Corrected Data, 300 x 250 x 224 bands
J97ATSUB.HDR ENVI Header for Above
JASP97WV.IMG ATREM Water Vapor Image
JASP97WV.HDR ENVI Header for Above
J97EFSUB.BIL AVIRIS ATREM with EFFORT Correction Applied
J97EFSUB.HDR ENVI Header for Above
J97EFSUB.DAT Effort Gains and Offsets
J97MNF_1.IMG VNIR MNF Transformed data, B 4 -102 less 33-34, 97-98
J97MNF_1.HDR ENVI Header for Above
J97MNF_1.ASC VNIR Eigenvalue plot data
J97MNF_2.IMG SWIR MNF Transformed data B173 - 223, 50 Bands
J97MNF_2.HDR ENVI Header for Above
J97MNF_2.ASC SWIR Eigenvalue plot data
J97PPI_1.IMG VNIR PPI image
J97PPI_1.HDR ENVI Header for Above
J97PPI_1.ROI ROI of VNIR PPI threshold
J97_SAV1.NDV VNIR N-D Visualizer Save State
J97_EM1.ASC VNIR ASCII File of Endmember Spectra - all EM
J97_EM1.ROI VNIR ASCII File of Endmember Spectra - all EM
J97_EM1A.ASC VNIR ROI File of Endmember Locations - selected EM
J97_EM1V.ASC VNIR ASCII File of Endmember Spectra - selected vegetation EM
J97_SAM1.IMG VNIR SAM Classes using J97_EM1A.ASC
J97_SAM1.HDR ENVI Header for Above
J97_RUL1.IMG VNIR SAM Rules
J97_RUL1.HDR ENVI Header for Above
J97SAM1V.IMG VNIR SAM Classes using J97_EM1V.ASC (vegetation only)
J97SAM1V.HDR ENVI Header for Above
J97RUL1V.IMG VNIR SAM Rules Classes using J97_EM1V.ASC (vegetation only)
J97RUL1V.HDR ENVI Header for Above
J97_UNM1.IMG VNIR Linear Spectral Unmixing using J97_EM1.ASC
J97_UNM1.HDR ENVI Header for Above
J97PPI_2.IMG SWIR PPI image
J97PPI_2.HDR ENVI Header for Above
J7PPI_2.ROI ROI of SWIR PPI threshold
J97_SAV2.NDV SWIR N-D Visualizer Save State
J97_EM2.ASC SWIR ASCII File of all Endmember Spectra
J97_EM2A.ASC SWIR ASCII File of selected Endmember Spectra
J97_SAM2.IMG SWIR SAM Classes using J97_EM2A.ASC
J97_SAM2.HDR ENVI Header for Above
J97_RUL2.IMG SWIR SAM Rules
J97_RUL2.HDR ENVI Header for Above
J97_UNM2.IMG SWIR Linear Spectral Unmixing Results
J97_UNM2.HDR ENVI Header for Above
JASP97.AVH JPL AVIRIS Header File
JASP97.WAV 1997 AVIRIS Wavelength file
JASP97.OCC JPL On-Board-Calibrator file
JASP97.SPC JPL Spectral Calibration File
JASP97.GN JPL DN-to-Radiance Gain File
Remote Sensing Test Site Used By JPL and others since early 1980s
AVIRIS Standard Datasets for 1992-97
Detailed Maps and Ground Spectra Available.
Figure 1: Jasper Ridge Orthophoto
Figure 2: Jasper Ridge Trails and Shaded Relief, Stanford University
Figure 3: Jasper Ridge Vegetation Map, Stanford Univerisity
Figure 4: Jasper Ridge multitemporal AVIRIS Data
Figure 5: Jasper Ridge AVIRIS Rock and Soil Spectra
Figure 6: Jasper Ridge AVIRIS Vegetation Spectra
The Figure below illustrates an approach for analysis of hyperspectral data that is implemented with ENVI
The following outlines in general terms the implementation of this approach. The student is expected to follow the procedures below, referring to previous tutorials and the ENVI User's Guide for guidance in performing specific tasks where required. The purpose of this tutorial isn't to teach you how to run the ENVI tools, but how to apply the methodology and tools to a general hyperspectral remote sensing problem
Files:
J97RDSUB.BIL JPL Radiance
Files:
J97ATSUB.BIL ATREM Apparent ReflectanceJ97WVSUB.IMG ATREM Water Vapor ImageUSGS_VEG.SLI Vegetation Spectral LibraryUSGS_MIN.SLI Mineral Spectral LibraryVEG_2GRN.SL Jasper Ridge, Spectral LibraryVEG_2GRN.HDR ENVI Header for Above
Files:
J97EFSUB.BIL ATREM Apparent Reflectance with EFFORT AppliedJ97EFSUB.DAT EFFORT Gains and Offsets
Files: Make your own MNF-Transformed dataset or review the results in the files below
J97_MNF1.ASC VNIR Eigenvalue ASCII DataJP7_MNF1.IMG VNIR MNF Eigenimages on 94 bands as listed aboveJ97_MNF2.ASC SWIR Eigenvalue ASCII DataJ97_MNF2.IMG SWIR MNF Eigenimages on 50 bands as listed above
Files: Generate your own PPI results and ROIs or review the results in the files below
J97PPI_1.IMG VNIR PPI ImageJ97PPI_1.ROI VNIR PPI Threshold ResultsJ97PPI_2.IMG SWIR PPI ImageJ97PPI_2.ROI SWIR PPI Threshold Results
Files: Extract endmembers and make your own ROIs or review the results below
J97_MNF1.IMG VNIR MNF Eigenimages on 94 bands as listed aboveJ97_MNF2.IMG SWIR MNF Eigenimages on 50 bands as listed aboveJ97EFSUB.BIL ATREM Apparent Reflectance with EFFORT AppliedJ97_SAV1.NDV VNIR n-d visualizer saved stateJ97_SAV2.NDV SWIR n-d visualizer saved stateJ97_EM1.ASC VNIR Saved ASCII Endmember SpectraJ97_EM2.ASC SWIR Saved ASCII Endmember SpectraUSGS_VEG.SLI Vegetation Spectral LibraryUSGS_MIN.SLI Mineral Spectral LibraryVEG_2GRN.SL Jasper Ridge, Spectral LibraryVEG_2GRN.HDR ENVI Header for Above
Files:
J97_EM1.ASC VNIR Saved ASCII Endmember SpectraJ97_EM2.ASC SWIR Saved ASCII Endmember SpectraJ97EFSUB.BIL ATREM Apparent Reflectance with EFFORT AppliedJ97_SAM1.IMG VNIR SAM ClassesJ97_RUL1.IMG VNIR SAM RulesJ97_UNM1.IMG VNIR Linear Spectral Unmixing ResultsJ97_SAM1.IMG SWIR SAM ClassesJ97_RUL1.IMG SWIR SAM RulesJ97_UNM1.IMG SWIR Linear Spectral Unmixing ResultsUSGS_VEG.SLI Vegetation Spectral LibraryUSGS_MIN.SLI Mineral Spectral LibraryVEG_2GRN.SL Jasper Ridge, Spectral LibraryVEG_2GRN.HDR ENVI Header for AboveSource: http://www.ltid.inpe.br