Version 2 (modified by amro, 17 years ago) (diff)


Known processing problems

CASI data missing GPS sync

If you're seeing azgcorr failing with ** read error on SCO input and, earlier in the output, azcaschk2 is reporting:

GPS message time to CASI clock time difference(s)...
  del_t : 
  freq  : 
  most frequent gap is: 0  secs

** NO (or insufficient) GPS messages or sync pulses
**    ... no sync saved

This means the CASI data files are missing the GPS sync markers (or azcaschk2 can't find them). As a consequence, scans can't be tied to navigation and azgcorr has nothing to work with. Typically, you'll be able to get the file to level 1 without problems, but level 3 can't be done.

To work around the lack of GPS sync, azcaschk2 allows you to use "frame headers" for sync instead. You need to add -FRsync to the azcaschk2 command line. In the normal batch files, amend the CSYNC line to read: CSYNC="-FRsync".

Image Ok but vctor layers not lined up

If the image looked okay after modifiying the GPSOFF and then the vector layers did not line up them it is better to modify the SCTOFF instead of GPSOFF. This will bring the vector layers to their places (e.g project 138 line 1 , 4 , 5 0

This should then process through to level 3, though you may need to correct for navigation timing.