Version 18 (modified by knpa, 14 years ago) (diff)


Eagle/Hawk Processing

Once the data have been unpacked and the nav data have been processed, the Eagle/Hawk data need to be run through the AZ Systems processing chain (primarily azspec, azimport, aznav and azgcorr).

Create the Config file is the script used to create the config file, which is in turn used to process the eagle and hawk lines. Before beginning, make sure the raw files are present as well as a processed navigation (sbet) file in applanix/proc and a suitable dem (see below). You may also need to create a text version of the logsheet.

Run with -h flag to get full usage help. An example command is below: -s s -n 5 -j 196 -y 2010 -l admin/196-10_Eufar10-03.txt Beware that the method is not robust and may fill in the wrong data details, especially for the per-line information. For unknown variables (global or flight line specific) a "?" will be inserted in the config file and should be replaced by hand.

If no log sheet is available, one can use the keywords on the command line to specify the global variables, using "" if requires a space within the name: -s s -n 4 --JDAY=200 --YEAR=2009 --PI="P.I. Name" --SITE="Over There" --PROJCODE=EX01_99

Adding keywords to the command line and using a logsheet results in the command line keywords taking precedent over the logsheet keyword. For a full list of keywords and their default values run: -h.

To use the logsheet just for the global variables you can add to command line --NOPERLINELOG. This will then use the logsheet for global variables, but not for per flight line values. For the per flight line values it will use and the raw eagle/hawk header and sbet files to extract average values for the speed/altitude/direction. But using this method will not name the scripts by flight line order on the logsheet, but by the filename of the raw data. Use the --NOPERLINELOG parameter if you wish to manually add the per line data to the config file.

Use the --EXCLUDE="n1 n2 n3 ... -1 m1 m2 m3... -1" parameter if you want to exclude line numbers from the config file. In this case -n linesNo, linesNo can be the number of lines with the previously specified ones excluded.

Processing the Lines

Easy Way

You should now have in the root of the project directory a .cfg file named with the year and julian day of the project. In order to run the project on the gridengine with default settings, run: <cfg_file>

By default this will do timing runs for each line on the gridengine using SCT offsets between -0.1 and 0.1.

Check against OS vectors.

Old-fashioned way

If you're unlucky and the automated script fails for some reason, you may need to do at least some of the processing the old-fashioned way.

  1. cd to the project directory in the workspace.
  2. Ensure that directories called "logs", "dem", "lev1" and "lev3" have been created.
  3. If there isn't one already, create a "calibration" symlink to the calibration data: ln -s ~arsf/calibration/<year> calibration.
  4. Create a DEM for the project. If it's in the UK you can use Nextmap data (try running in the project directory to do it automatically, otherwise see the wiki page). If it's non-UK, you'll need to use LiDAR data (you may wish to use this anyway if it's available - see here? on how to do this using a script), or failing that SRTM 90m data. Copy it into the dem directory.
  5. Create a symlink to the SBET file if there isn't one already.
    1. cd applanix
    2. ln -s Proc/sbet_01.out apa<year><jday>.sbet
    3. cd ..
  6. Copy the sample config file from ~arsf/sample_scripts/<year> to the project directory in the workspace - you need, and template_specim_config.cfg.
  7. Comparing the .cfg file with the logsheet, replace the entries that need to be replaced as appropriate. You should be able to see which bits these are in the sample scripts because they'll have keywords instead of values. You will need to create one cfg file section flightline per sensor.
    • Note that dates must be of the form DD/MM/YY or DD/MM/YYYY (must use / as a separator)
    • Note that times must be of the form HH:MM:SS (must use : as a separator)
  8. Run the processing scripts. You can either do this via the gridengine (recommended) by running, or you can do it on your machine one line at a time on your machine by running with appropriate arguments for each line/sensor combination from the root of the project directory. If you do the latter you should pipe the output to tee to ensure a log file is generated: rune/ 2>&1 | tee rune/e12301.log.
  9. Check each set of flightlines to work out which has the best timing offset (ie has the straightest roads, etc). Make a note of the timing offset values in the ticket
  10. Check against OS vectors


To return sensible results you will need a dem. One should have already been completed in the unpacking stage. If not, it will need to be created. If the project is in the UK you can use Nextmap data (try running in the project directory to do it automatically, otherwise see the wiki page). If it's non-UK, you'll need to use LiDAR data (you may wish to use this anyway if it's available - see here? on how to do this using a script), or failing that SRTM 90m data. Copy it into the dem directory. Once you've done this include the DEM file in the config file by entering "dem=<dem_file_name>" under the DEFAULT section.



If you get something in the log file like:

End of POSATT file with NO Specim sync found
no sync within 5.00 secs of raw file header time: 49915.66

then there is no sync info in the nav file for that line and and the range of possible sct values will increase (up to a few seconds). You will need to include 'has_sync = false' in the config file line entry and input a wider range of scts, e.g.

has_sync = false
sctend = -1
sctincrement = -0.1
sctstart = 1


A less likely reason for the above output is that the raw header file in question contains invalid GPS times (either start time or end time) and therefore also results in not lying within the times of the .nav file. If both GPS Starting Position and GPS Start Time are missing (accordingly for End Position/End Time) then the best guess is to replace the invalid time/position with the raw header file from the other sensor (eagle/hawk), making sure that it is the correct corresponding flightline. If only one of the two are missing, time or position, then the navigation files should be used to find the missing data, this is easier done when the position is missing (open .gpb file from applanix/extract) but still possible when the time is missing (.gpb again, but will have to track position).


If you get something in the log file like:

flight line may have a turn in it
heading spread over approximately: 120 degs

run terminated due to turn

then there is a bend in the line that is too sharp. You need to add a -bend flag to the azcorr arguments for the line entry in the config file, e.g.

azgcorr_args_extra = -bend


Once processed, it is best to exclude the lines which are causing the problems by including a -l flag in azspec followed by the line numbers delineating the part of the line you want to keep, then reprocessing. E.g. if the bend is at the start of the line:

azgcorr_args_extra = -bend
azspec_args_extra = -l 50 2000

will exclude the first 50 lines.

For anything else, check: Common or known problems. This is now a bit out-of-date - if your solution isn't on there then please add it once you find what it is.


Once you're satisfied with the processed data, you need to create a delivery directory for it.