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Isis 2 Documentation


impcal Documentation

impcal - Radiometric correction of Pathfinder IMP camera images



INTRODUCTION
------------


"impcal" performs radiometric corrections to images acquired by the
Pathfinder IMP camera. "impcal" performs dark subtraction, readout
correction and flat field corrections.  "impcal" gives the user the
option of writing the output image values as counts/ms or as intensity
units.  See the user parmeter, ABSOL.  The default is units of intensity
(W/m^2/um/ster).


Programmer:  Tracie Sucharski,  U.S.G.S., Flagstaff, AZ

ParmDescriptionDefault
FROM
Input file name
NONE
TO
Output file name
NONE
RESPONSE
Responsivity value
--
OTYPE
Output pixel type
3
ORANGE
Output pixel data range
--
USERNOTE
User comment
" "

ADDITIONAL NOTES:

ParmDescription
FROM
Specify the input file to be corrected.
TO
Specify the output file. The result will be the
radiometrically corrected image. The output values can
either be output as counts/ms or absolute radiance.
The ouput file can be 8, 16, or 32 bit which is defined
by the OTYPE parameter shown below.
RESPONSE
This is used to convert the data into units of intensity
(W/m^2/um/ster).  This values should be in units of
(DN/s)/(W/m^2/um/sr).  If you wish to leave the results
in counts/ms, enter a value of 1.0 in this parameter.
OTYPE
Output pixel data type. Permitted values are:
    0 - output type is same as input file pixel type
    1 - 8-bit (integer with type conversion parameters)
    2 - 16-bit (integer with type conversion parameters)
    3 - 32-bit (floating point)

ORANGE
Output pixel data range.  If the output pixel type is 1
(8-bit integer with type conversion parameters) or 2 (16-bit
integer with type conversion parameters), then the type
conversion parameters in the output file will be set to
values that allow representing the specified range of output
values.  Output values outside this range will be stored as
the special "representation saturation" value.

The ORANGE parameter is ignored if the output pixel type is
3 (32-bit floating point) since type conversion parameters
are not applicable to floating point pixel values.

If both ORANGE(1) and ORANGE(2) are 0.0, then the type
conversion parameters in the output file will automatically
be set to allow representing the same range of values as can
be represented in the input file.  (The user will be
required to supply a specific range for ORANGE if the input
pixel type is 3 (32-bit floating point) and the output pixel
type is 1 (8-bit with type conversion parameters) or 2
(16-bit with type conversion parameters)).
USERNOTE
Comment from the user.  This will be recorded in the ISIS
session log file and also in the History entry that is put
into the History object of the output file.

Last updated: Jan 31 2005
File: pdfs2.html

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