Had a request for help from a user of existing CASI data (Jon Atherton) who was not an original PI but obtained some 2005 flight data from NEODC:

Hello,

I'm a complete novice at preprocessing CASI data. I have access to the NEODC online data sets, and I would like to use CASI data from Sitia, 2005 (http://neodc.nerc.ac.uk/cgi-infrastructure/data_browser/data_browser/neodc/arsf/2005/MC04_15).
I need about 15 bands worth centred at 685 nm (band 32 to 47) from images c130021b and c130041b.

Your colleague (Gary Llewellyn) kindly provided me with the FTP for AZGCORR. I had a go with the basic line of code (provided in the tutorial) which produced a blurred image on an angle, when compared with the three bands-worth of images already processed to level 3b which are available online. Any help on correcting the blurriness would be greatly appreciated.

The only code I used was (I don't have a DEM):

 "./azcor -bl 1 -1 -p 2.0 2.5 -1 c130021b.hdf -3 c130023a.hdf"


Best wishes,

Jon Atherton

PhD student
University of Edinburgh

Replied to the query (suggested he applied a correct projection, used square pixels and tried some different bands), which seems to have solved the problem.

What if any support level should we be providing to new users of existing data? On the one hand we don't want to leave ourselves open to potentially large open-ended support requests from non-PIs, on the other it's in our interests to have ARSF data as widely available and used as possible.

Ricardo contacted us yesterday with:

  Recently you offered your help with any general Eagle/Hawk/CASI/ATM processing issues and we would like to consult about our Eagle/Hawk data processed with azgcorr. As you maybe are aware, Doñana (SW Spain) was overflown March last year and we have been using azgcorr to produce Level 3 geocorrected data, and able to apply atmospheric corrections with the great help of Andrew Wilson from CEH. However, to manage the huge files of the geocorrected Level 3 data at full spatial and radiometric resolution is still a pain because of file size, specially in cases in which we have lots of ground-thruth positions in different flight-lines (our main EUFARNet aim and goal is to map 2 allien plant species).

   That is why we are also trying to obtain IGM files for ENVI (X and Y coordinate files that help in overlying ground-truth areas, more info at http://www.ittvis.com/services/techtip.asp?ttid=3816), and this is why we are testing
the possibility to do it with PARGE since AZGCORR has not this option (although the calculations must be embedded somewhere in the code, during the geocorrection process, as Andrew Wilson indicated). This might simplify the process of overlaying ground-truth on flight-lines before applying any geocorrection to the final product (mostly classification maps). Would it be possible to incorporate such an option on AZGCORR processing?

As this is not the only project in which we are working, and we are not experienced hyperspectral data users, it is taking us longer than we would have liked to analyse the data.

The IGM files appear to be ENVI's method for specifying per pixel coordinates. This is the same issue as #109.

Replying to Ricardo with the info we have on this, and the current tentative plan for this to be implemented pending availability of development time. Raising the importance of that issue too.

With the recent acquisitions of the first FODIS data, we attempted to process some using azspec and appear to have a problem. By comparison with the solar spectrum (​http://fsf.nerc.ac.uk/img/g37_grph.gif) and a Caligeo processing of the same line, there is a clear discrepancy. Image below shows a worst case selection of the azspec FODIS output.

relevant part of processing log:

azspec  -- ver: 1.1.7 Apr  3 2008   (C) Azimuth Systems UK 2005, 2007

Raw file header: eagle/VNIRsecloudtest-1.hdr
Raw file       : eagle/VNIRsecloudtest-1.raw
Dark frames at end of image file, 152 frames starting at: 3932
Image lines corrected from: 4083  to 3931
Using Tr multiplier from spectral binning[2]:  1.00  fsmscale is now: 0.000100  Tr: 0.002000  integ: 20.0
Optics from basic details and binning port fov: 16.129  full fov: 34.688 corr oa: 512.00 scpixels: 953
image file frame count  start: 60092  end: 64047  total lines: 3955 file lines: 3931

Dark frames at end of raw file: 152  darks to be used: 50

Dark frames used:  49.0   scale: 0.02041
Radcal file header: calibration/eagle/SN100022_130207_XB.hdr
Radcal file       : calibration/eagle/SN100022_130207_XB.cal
Config file       : calibration/eagle/SN100022_130207_XB.cfg

Using HDF file: lev1/eJJJ011b_gpt0.0.hdf
HDFStart  fov: 34.7 fovp: 16.1 scpixels: 953

New BIL  bands: 252 pix: 953 lines: 3955
   HDF image data: CAimage  bands: 252 pixels: 953 lines: 3955
   FODIS (ILS) bands: 252 pixels: 1 lines: 3955
2 frame(s) missing from: 60094  to 60097 line: 2 cline: 3
2 frame(s) missing from: 60098  to 60101 line: 6 cline: 5
2 frame(s) missing from: 60102  to 60105 line: 10 cline: 7
1 frame(s) missing from: 60112  to 60114 line: 20 cline: 15
1 frame(s) missing from: 60115  to 60117 line: 23 cline: 17
3 frame(s) missing from: 60118  to 60122 line: 26 cline: 19
2 frame(s) missing from: 60126  to 60129 line: 34 cline: 24
1 frame(s) missing from: 60130  to 60132 line: 38 cline: 26
2 frame(s) missing from: 60133  to 60136 line: 41 cline: 28
2 frame(s) missing from: 60138  to 60141 line: 46 cline: 31
2 frame(s) missing from: 60142  to 60145 line: 50 cline: 33
2 frame(s) missing from: 60146  to 60149 line: 54 cline: 35
1 frame(s) missing from: 60157  to 60159 line: 65 cline: 44
2 frame(s) missing from: 60964  to 60967 line: 872 cline: 850
**FrameProcess - HDF write error for ILS line: 3955
SpecNavProc gotsync: 0  synclater: 1

Nav syncstart from image file header of: 49107.62500 gps secs of day
sync entries set for later use
    start frame: 0 end: 3954
    start frame time: 49107.624900  frame time increment: 0.033333 secs

writing new NAV vgroup

Processing summary...

  data from   : AISA HS Instrument, SW ver 2.800
  sensor ID   : 100022
  lens FOV    : 34.69 degs
  raw file    : eagle/VNIRsecloudtest-1.raw
  BIL lines   : 3931  available
  acq date    : 31/01/2008  day: 31
  rec times   : start: 13:38:27.62  end: 13:40:45.19
  binning     : 2  spectral  1 spatial
  integration : 20.00  msecs
  frame rate  : 30.00  fps
  radiance sc : 1000.000
  HDF file    : lev1/eJJJ011b_gpt0.0.hdf
  Image data  :  pix: 72 to 1024  saved to HDF-SDS item: CAimage
  FODIS (ILS) :  pix: 28 to 32 saved to HDF-SDS item: CAils
  pixels      : 1024
  bands       :  252  re-ordered blue to red
  image lines : 3955  frameIDs at line (0): 60092 and line (3954): 64047

Processing applied...

  frame shift smear correction, line shift scale: 0.00010
  dark frame subtraction, lines averaged: 50  dark frames from raw file
  radiometric calibration using file: calibration/eagle/SN100022_130207_XB.cal
  ** total pixels overflowed after calibration: 556
  FODIS averaged
  ** no FODIS ratio applied

Processing times  : calibration: 64.2 total: 237.6  secs

halting after azspec (no need to do the rest)

Sent a copy of the Caligeo and azspec processed files, the raw data and the script to Bill, with a brief explanatory note.