I'm working on a procedure that will help automate the hyperspectral workflow I've been repeating by hand to whiten my data and associated spectral library. The idea is to provide the file name of a hyperspectral file and an ROI file that identifies a convenient uniform area to use for the shift difference noise calculations. I attempted to use the ENVI 'ForwardMNFTransform' Task, but it doesn't appear that this task allows you to perform a shift difference noise calculation. Thus, I have resorted to the MNF_DOIT routine, but I am again encountering problems applying the shift difference.

Here's my current code:

PRO whitening_automation

; Specify input file and ROI to use for noise statistics calculation (ideally, a uniform dark area)

inFile = FILEPATH('006_140820_175610_L2S.dat', ROOT_DIR="F:\L2Data\")

roiFile = FILEPATH('006_140820_175610_uniform.roi', ROOT_DIR="F:\L2Data\")

; Also provide an output directory and root filename to use for output files

outDir = "F:\HSI_demo\"

rootName = "006_140820_175610"

; Open input file and load the uniform ROI to use for whitening

raster = e.OpenRaster(inFile)

ENVI_Restore_ROIs, roiFile

; Get the input file ID and query the file for dimensions and number of bands

fid = ENVIRasterToFID(raster)

ENVI_File_Query, fid, DIMS=dims, NB=nb

; Get the pointer ID for the ROI

roiID = ENVI_GET_ROI_IDS(FID=fid)

; Now perform MNF transform

ENVI_Doit, 'MNF_Doit', $
FID = fid, $
DIMS = dims, $
POS = Lindgen(nb), $
OUT_NAME = outDir+rootName+'_mnf' $
SD_DIMS = roiID, $
/SHIFT_DIFF, $
STA_NAME = outDir+rootName+'_mnf.sta', $
NOISE_STA_NAME = outDir+rootName+'_mnf_noise.sta', $
/NO_PLOT, $
R_FID = mnf_fid

Can anyone identify where this has gone wrong or provide an alternative that uses the ENVI 'ForwardMNFTransform' Task? Thanks!