lev2tolev2 Documentation

lev2tolev2 - Make tfile for level 2 to level 2 conversion
This program generates a transformation file (tfile) which will
convert a level 2 (map projected) cube to a different level 2
cube (a different map projection).  For example, a cube in the
Sinusodial map projection can be transformed into a Simple
Cylindrical map projection.  The tfile and the level 2 cube
must then been input to the program "geom" which transforms
the pixels in the input cube to the proper position in the
output cube.

Note:  The map projection can remain the same, while the
latitude/longitude range, pixel resolution, or map projection
parameters (e.g., center longitude) can be changed.

PROGRAMMER: Jeff Anderson, USGS, Flagstaff, Az

Input "level 2" cube name
(default extension is .cub)

NONE

Map projection and parameters
(e.g., MAPPARS="SINU:0")

NONE

Target or target definition
file (default=FROM targdef)

--

Latitude range
(default=FROM range)

--

Longitude range
(default=FROM range)

--

Image resolution (km/pix)
      or

--

Image resolution (pix/deg)
(default=FROM value)

--

Transformation file
(no default extension)

tfile.dat

Latitude system
(default=FROM latsys)

--

Longitude system
(default=FROM lonsys)

--

Trim outside lat/lon boundaries

NO

ADDITIONAL NOTES:

Parm	Description
FROM	Input cube file name. If the file extension is omitted, then ".cub" will be assumed.
MAPPARS	This parameter is used to specify the map projection and its specific parameters. For example, "SINU:0" implies Sinusoidal map projection with a central longitude of 0. The program will automatically calculate default values for projection specific parameters and therefore "SINU:" is an acceptable input. **NOTE** For a detailed explanation of MAPPARS, tutor the mappars.pdf (i.e., TAE> tutor mappars).
TARGDEF	Enter a target definition file, target name (which will be used to generate the default target definition file), or use the default (copy target information from the FROM file. Example: TARGDEF=mars The software will try to find files: $ISISDATA/targets/mars.def.1 $ISISDATA/targets/mars.def.2 $ISISDATA/targets/mars.def.3 etc. Or enter a user written target definition file path and name: TARGDEF=/work1/elee/mars.def.3 If you want radii different from the defaults in the system, you cannot enter the radii numbers here. Copy the system target definition file to your area and edit, putting the radii you want into the definition file. Then TARGDEF=your_ file. Note also that the target definition file name will be written to the cube labels, and you will help yourself if you use a version system as is being done in ISIS. Each time you make edits to your target definition file, rename it and keep the old versions lying around somewhere where you can find them.
LATRANGE	Latitude range of the desired output cube which will be produced by "geom". If the range is not entered then it will be automatically computed. If the range is entered then LONRANGE must be entered as well.
LONRANGE	Longitude range of the desired output cube which will be produced by "geom". If the range is not entered then it will be automatically computed. If the range is entered then LATRANGE must be entered as well.
KM	This specifies the map resolution in kilometers/pixel. If a value is not entered then the average resolution of the cube will be automatically calculated. If a value is entered then a value must not be entered for DEG.
DEG	This specifies the map resolution pixels/degree. If a value is not entered then the average resolution of the cube will be automatically calculated. If a value is entered then a value must not be entered for KM.
TFILE	This is the name of the transformation file (tfile) to be generated. The input cube, along with this tfile must be input into the program "geom" in order to produce a level 2 cube.
LATSYS	This parameter is used to define the latitude system of the user-entered latitude parameters and the keyword labels. Valid values are either OGRAPHIC or OCENTRIC. The default is taken from the labels of the FROM file. Your selection is written to the IMAGE_MAP_PROJECTION group of the labels of the cube under the keyword name KEYWORD_LATITUDE_TYPE
LONSYS	This parameter is used to define the longitude system computed by "lev2" programs. Valid values are either 180 or 360. The default is taken from the labels of the FROM file. If lonsys=360, longitudes will be output in the range of 0 to 360. The value 180 implies longitudes will be output in the range of -180 to 180. Your selection is written to the IMAGE_MAP_PROJECTION group of the labels of the cube under the keyword name LONGITUDE_SYSTEM. This affects programs which output or use the latitude/longitude of points such as qview and lev2grid.
TRIM	If TRIM=YES, the program will create a TFILE that will cause "geom" to project only the area within the latitude/longitude boundaries defined by the user via LATRANGE/LONRANGE or determined by the program in the event the user did not enter a range. If TRIM=NO, no trimming will be done.