← Revision 8 as of 2017-12-22 12:17:02
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In general, this program ingests images into SPC, building the sumfiles and nominals.
make_sumfiles takes in the name and camera position of the images from make_sumfiles.in. The program then
converts the image into the <filename>.DAT format in IMAGEFILES
appends the image name onto PICTLIST.TXT
All the vectors in the sumfiles and nominals are in a body fixed frame with the origin at the center of the target body. The origin might be off a little bit, which means you may have to use shift eventually. The ck and spk kernel names in make_sumfiles.txt must cover the time span of all the images being ingested. Otherwise, make_sumfiles will not work. This program is non-standard. It frequently requires different versions for different missions to get the data in a form usable by SPC. Although the goal is to make a single version that does it all, each mission has a different image format. If the image name is already listed in PICTLIST.TXT, make_sumfiles will not make NOMINALS or SUMFILES.
- Spice kernel file (SPICE)
make_sumfiles.txt - list of SPICE kernels
IFRAME.TXT - picture properties
PICTLIST.TXT - list of pictures
NOMINALS - nominal navigation information and uncertainties
SUMFILES - camera properties and navigation information
The following sample shows the standard inputs and the list of options for make_sumfiles:
~/bin/e.make_sumfiles Use B-Frame? (y/n) n 0. Create SUMFILES & NOMINALS and .. 1. Update old NOMINALS and .. 2. Update old SUMFILES 0
Usually, the B-Frame is not selected. The author has never selected it.
Enter the appropriate option:
0 Create SUMFILES & NOMINALS and .. - Completes both operations and ends.
1 Update old NOMINALS and .. - Completes NOMINALS operation and ends.
2 Update old SUMFILES - Issues the following prompts:
Update UTC? (y/n) Update image thresholds? (y/n) Update camera parameters? (y/n) Reset geometry? (y/n) Reset sigmas? (y/n)
- Update UTC - Updates time a picture was taken.
- Update image thresholds - Changes image constraints.
- Update camera parameters - Changes the camera focal length, K-matrix, etc.
- Reset geometry - Resets position and pointing back to nominal.
- Reset sigmas - Resets uncertainty back to nominal.
Do we need descriptions (default or suggested choices?) for each of these and what happens?
Combines the converted image file with the image number, spacecraft state, spacecraft position & velocity and pointing information along with the associated calculated errors (Sigmas).
Option 0 creates .SUM and .NOM files for any new images but leaves all others C unchanged. Additionally, option 1 updates all .NOM files. Option 2 dies all of the C above and makes changes in all .SUM files. The possible changes, specified in new C entries in make_sumfiles.txt, are: C C Update UTC? (y/n) C Update image thresholds? (y/n) C Update camera parameters? (y/n) C Reset geometry? (y/n) C Reset sigmas? (y/n) C C The procedure first uses SPKEZ to calculate the spcaecraft - object vector SCOBJ and C the unit vector to the Sun in inertial space at the ephemeris time ET of an image. C It also determines the light time LT from the s/c to the target. It then determines C the transformation matrix from the camera frame (INST) to inertial space (TTVI) at C time ET using the SPICELIB routine PXFORM. Now all relevant quantities are available in C inertial space. In SPC all these quantities are used in the body-fixed frame, so we again C use PXFORM to translate from inertial to body-fixed (TIPM). We do this not at ET but at C ET-LT, since this is when the light forming the image left the target body.
(Compiled by KD)