This program extracts a sub-area from a cube based 
      on user defined parameter values.  The extracted area can also be 
      sub-sampled by specifying a line and sample increment. 
    
     
      A sub-area selected for extraction must be 
      contiguous. That is, the program will not allow non-continuous cropping 
      such as lines 1-5, 10-30, and 80-100. However, the contiguous area can be 
      sub-sampled by specifying how many pixels to increment or skip.  For 
      example, to select every third line (1, 4, 7, 10 ...) to be written to 
      the output cube, use a line increment (LINC) of three.
    
    
      The parameter PROPSPICE applies to Level1 images.  The 
      SPICE information must have been propagated to the cropped 
      output cube to obtain any camera geometry or photometric information.  
      The default setting for PROPSPICE is "TRUE."  When the default setting is 
      used, all the keywords in the labels of the input file are transferred to 
      the output file.  In addition, the keywords that describe the area that was 
      extracted out of the input cube are also added to the AlphaCube group in 
      the labels.
    
    
      For a Level1 image, the keywords contained within the AlphaCube 
      group in the labels describe the original file size and the area that was 
      extracted. The AlphaCube and SPICE kernels information are very important 
      to compute accurate geometric and photometric information using the cropped 
      Level1 cube.
    
  
    | Level1 labels using PROPSPICE=TRUE: | 
    Level1 labels using PROPSPICE=FALSE: | 
  
Group = Kernels                                                               
    NaifFrameCode             = -53031				
    LeapSecond                 = $base/kernels/lsk/naif0009.tls		      
    TargetAttitudeShape       = $base/kernels/pck/pck00009.tpc
    TargetPosition            = (Table, $base/kernels/spk/de405.bsp) 	 
    InstrumentPointing        = (Table, $odyssey/kernels/ck/m01_sc_ext11.bc,
                                 $odyssey/kernels/fk/m01_v29.tf)	
    Instrument                = Null					 
    SpacecraftClock           = $odyssey/kernels/sclk/ORB1_SCLKSCET.00187.tsc
    InstrumentPosition        = (Table, $odyssey/kernels/spk/m01_ext11.bsp)
    InstrumentAddendum        = $odyssey/kernels/iak/themisAddendum003.ti
    ShapeModel                = $base/dems/molaMarsPlanetaryRadius0005.cub
    InstrumentPositionQuality = Reconstructed				
    InstrumentPointingQuality = Reconstructed				
    CameraVersion             = 2					
  End_Group
  Group = AlphaCube                                                           
    AlphaSamples        = 320						      
    AlphaLines          = 3600						      
    AlphaStartingSample = 99.5						      
    AlphaStartingLine   = 9.5						      
    AlphaEndingSample   = 199.5 					      
    AlphaEndingLine     = 109.5 					      
    BetaSamples         = 100						      
    BetaLines           = 100						      
  End_Group								      
 | 
Group = Kernels
    NaifFrameCode = -53031
End_Group
 Group = AlphaCube
   AlphaSamples        = 320
   AlphaLines	       = 3600
   AlphaStartingSample = 99.5
   AlphaStartingLine   = 9.5
   AlphaEndingSample   = 199.5
   AlphaEndingLine     = 109.5
   BetaSamples         = 100
   BetaLines	       = 100
 End_Group
 
 
 
 
 
 
 
 
 
 
 
 | 
    
      For a Level2 image or a mosaic, the Mapping group keywords in 
      the labels are updated or removed depending on the settings used to crop 
      the input image.  Once an image has been cropped, the keywords 
      MinimumLatitude, MaximumLatitude, MinimumLongitude, and MaximumLongitude 
      are recomputed and the values updated in the labels for rectangular 
      projections with straight line meridians and parallels.  The keywords are 
      removed from the labels for projections with curved meridians and 
      parallels.  Use the map2map application if the keywords 
      MinimumLatitude, MaximumLatitude, MinimumLongitude, and MaximumLongitude 
      must be retained in the labels.  If the parameters LINC and SINC are not 1 
      and the values are equal, then the map Scale and PixelResolution are recomputed and the values
      updated in the labels.  Otherwise, Scale and PixelResolution keywords and
      values are removed 
      from the labels.  The UpperLeftCornerX and UpperLeftCornerY are recomputed
      based on the settings used to crop the input image and updated in the labels
      for all projections as shown in the example below.  
    
  
    | Level2 labels of uncropped image: | 
    Level2 labels of cropped image: | 
  
Group = Mapping                                           
  ProjectionName       = Equirectangular		  
  CenterLongitude      = 0				  
  TargetName	       = MOON				  
  EquatorialRadius     = 1737400.0 <meters>	  
  PolarRadius	       = 1737400.0 <meters>	  
  LatitudeType         = Planetocentric 		  
  LongitudeDirection   = PositiveEast			  
  LongitudeDomain      = 180				  
  MinimumLatitude      = -60.62302099			  
  MaximumLatitude      = -59.30333301			  
  MinimumLongitude     = -161.213427			  
  MaximumLongitude     = -158.574051			  
  UpperLeftCornerX     = -2444266.0		  
  UpperLeftCornerY     = -1798275.5		  
  PixelResolution      = 7.5 <meters/pixel>
  Scale 	       = 4043.1133898866 <pixels/degree>
  CenterLatitude       = -60
  CenterLatitudeRadius = 1737400.0
End_Group
 
 | 
Group = Mapping
   ProjectionName	= Equirectangular
   CenterLongitude	= 0
   TargetName		= MOON
   EquatorialRadius	= 1737400.0 <meters>
   PolarRadius  	= 1737400.0 <meters>
   LatitudeType 	= Planetocentric
   LongitudeDirection	= PositiveEast
   LongitudeDomain	= 180
   UpperLeftCornerX     = -2429273.5
   UpperLeftCornerY     = -1813268.0
   PixelResolution	= 15.0 <meters/pixel>
   Scale		= 2021.5566949433 <pixels/degree>
   CenterLatitude	= -60
   CenterLatitudeRadius = 1737400.0
End_Group
 
 | 
    
    WARNING:
      If the cropped image is displayed with the application qview, the latitude 
      and longitude reported by the application will be correct for the cropped files. 
      The mappt application can be used to compute the latitude 
      and longitude at a specific point in a cropped cube.  
      
 
      The minimum and maximum latitude and longitude range are not recomputed and the 
      keywords are deleted from the labels when the input image is in a non-rectangular
      projection.  Unfortunately there is not a generic way to update the ranges for 
      all projections so only the values for rectangular projections are recalculated
      and updated in the labels.
      
 
      The cropped images may be included in a list to create a mosaic with 
      automos. All the cropped images included in the input list must contain 
      the same mapping values. If automos fails because of the cropped images, 
      the user may need to specify the MINLAT, MAXLAT, MINLON, and MAXLON values of 
      the output mosaic for some ISIS versions.      
    
   
| Jim Mathews | 1994-04-20 | 
      Original version
     | 
| Jeff Anderson | 2002-08-05 | 
      Converted to Isis 3.0
     | 
| K Teal Thompson | 2002-11-18 | 
      Added examples
     | 
| Jeff Anderson | 2003-01-28 | 
      Removed crop from the Utility category
     | 
| K Teal Thompson | 2003-02-03 | 
      Make images smaller
     | 
| K Teal Thompson | 2003-02-04 | 
      Added red rectangle to input image of example to illustrate crop area.
     | 
| K Teal Thompson | 2003-03-19 | 
       Moved images to /assets/image directory and thumbnails to /assets/thumb directory.
     | 
| Stuart Sides | 2003-04-04 | 
      Fixed problem with isiscvs not checking in the thumb and image directories.
     | 
| Stuart Sides | 2003-04-25 | 
      Added extraction labels
     | 
| Stuart Sides | 2003-05-16 | 
      Modified schema location from astrogeology... to isis.astrogeology..."
     | 
| Stuart Sides | 2003-07-29 | 
      Modified filename parameters to be cube parameters where necessary
     | 
| Jeff Anderson | 2004-02-16 | 
      Replaced extraction group with AlphaCube group and propagated other
      labels.
     | 
| Jeff Anderson | 2004-02-16 | 
      Added LINC and SINC parameters and set defaults for all parameters
     | 
| Brendan George | 2006-12-29 | 
      Fixed to allow input band selection
     | 
| Elizabeth Miller | 2007-02-01 | 
      Modified to adjust the upper left corner x and y values in the mapping group 
      of the output cube if the input cube is projected
     | 
| Steven Lambright | 2008-05-13 | 
      Removed references to CubeInfo 
     | 
| Steven Lambright | 2008-08-04 | 
      Added spice propagation option PROPSPICE. Fixed description of NLINES, NSAMPLES
      and now line associated and sample associated tables are modified when crop is run.
     | 
| Steven Lambright | 2008-08-06 | 
      Changed default of PROPSPICE to true. Sample/Line associated tables are no longer modified
      due to conflicts with other programs, such as pad, which doesn't know what data values
      to add to the tables.
     | 
| Steven Lambright | 2009-06-30 | 
      When an invalid projection exists the proper error should now be thrown.
     | 
| Janet Barrett | 2009-10-21 | 
      Now uses the SubArea class to produce output cube labels 
      with corrected Mapping, Instrument, and AlphaCube groups.
     | 
| Tracie Sucharski | 2012-12-06 | 
      Removed unnecessary include of Projection.h.  References #775
     | 
| Stuart Sides | 2013-06-23 | 
      Modified the calculations for number of lines and samples to use double precision math
      and then round up instead of integer math with truncation. When the number of lines or
      samples does not divide evenly by the linc or sinc values there will be one additional
      line or sample in the output cube.
     | 
| Janet Barrett | 2014-02-10 | 
      Delete input cube between successive runs of the program. This makes sure that the
      projection information is initialized each time the program is run in the GUI.
      Fixes #1500.
     | 
| Ella Mae Lee | 2014-04-02 | 
      Updated the documentation, fixes #1622 and #1688.
     | 
| Jeffrey Covington | 2015-01-15 | 
      Removed unreachable code.
     |