ISIS Application Documentation
     Create a digital elevation model from one or more control network files. 
  
 
          Description
        
    
       The cnet2dem applicaton produces an interpolated digital elevation model (DEM) from
       one or more control networks.  There are fourteen different algorithms that 
       may be selected that provide either absolute radius values or other information,
       such as radius and point distance statistics, computed at each output DEM 
       pixel value. The range and type of the DEM generated from cnet2dem is 
       a standard ISIS map definition or a projected ISIS cube file containing a
       map definition. You can select any number of algorithms in the ALGORITHM 
       parameter. The output cube will contain the same number of bands in the 
       same order algorithms are specified in the parameter. The BandBin group 
       Name parameter will also contain the name of the algorithm that 
       cooresponds to the data contained in each band.
     
    
        Note that the control network is expected to be the output results of 
        the bundle adjustment computed by jigsaw. Additionally, 
        jigsaw must have been used to solve for radius. Otherwise, you 
        will be using the apriori radius which is typically the PCK defininition 
        (will will result in the ellipsoid).
     
    
         The adjusted latitude/longitude coordinate is used to compute the 
         location of all the control points. The adjusted coordinates are 
         compute by jigsaw. If it doesn't exist, the apriori coordinate 
         will be used but know that this coordinate is typically computed from 
         each reference image in each control point (so it may not be 
         consistent).
     
    
        Also, in some cases, one or more of the algorithm radius bands in the 
        output of cnet2dem may be sufficient for direct use as an ISIS 
        shape model (after demprep is run!). However, this is generally 
        not the case and some of the radius bands may require a series of 
        filters to smooth out the results.
     
   
 
          Categories
        
 
              History
          
| Kris Becker | 2015-11-13 | 
        Original Version
     | 
 
| Tyler Wilson | 2016-03-10 | 
       Minor documentation corrections.
     | 
 
 
 | 
 
 
                Parameter Groups
            
Input
| 
                    Name
                     | 
                    Description
                     | 
 
| CNET | Master control network file to match. | 
 
| CNETLIST | List of merger control network files. | 
 
| MAP | Specifies a file containing the output map specfications. | 
 
 
Output
| 
                    Name
                     | 
                    Description
                     | 
 
| TO | Output DEM ISIS cube | 
 
| TRIM | 
          Null all pixels outside lat/lon boundaries.
         | 
 
 
Parameters
| 
                    Name
                     | 
                    Description
                     | 
 
| SEARCH | Optional tolerance for radial search range (meters). | 
 
| DISTANCE | 
               Specifies the radial search distance to search.
            | 
 
| KDNODES | Specify the leaf size of the kd-tree. | 
 
| NEIGHBORS | Specify the number of nearest NEIGHBOR points | 
 
| MINPOINTS | Specify the minimum number of search points per pixel. | 
 
| SIGMARADIUS | 
               Specifies noise tolerance in radius.
            | 
 
| ALGORITHM | Type of data to provide a each output pixel location. | 
 
 
 | 
 
Output:
                        TO
                         Description
                       
             Specifies the name of an output ISIS cube file that is created to 
             write the DEM. The output DEM may require demprep to be run 
             on it before it can be used as an ISIS DEM shape model.
        
| 
                             Type
                            | cube | 
| 
                               File Mode
                              | output | 
| 
                               Pixel Type
                              | real | 
| 
                               Filter
                              | *.cub | 
 
 
Output:
                        TRIM
                         Description
                       
          If this option is selected, pixels outside the latitude/longtiude
          range will be trimmed (set to null).
          This is useful for certain projections whose lines of latitude and
          longitude are not parallel to image lines and sample columns.
        
| 
                             Type
                            | boolean | 
| 
                               Default
                              | FALSE | 
 
 
Parameters:
                        DISTANCE
                         Description
                       
               Radial distance in meters to search for control points measured 
               from the center of the ouput map pixel. 
           
| 
                             Type
                            | double | 
| 
                               Internal Default
                              | None | 
 
 
Parameters:
                        KDNODES
                         Description
                       
              Number of leafs in the kd-tree structure.
           
 
Parameters:
                        NEIGHBORS
                         Description
                       
            Specify number of control points that will be selected in the 
            nearest NEIGHBOR search query to produce the output DEM pixel 
            values.
          
 
Parameters:
                        MINPOINTS
                         Description
                       
            Specify number of minimum number of points to accept from the RADIAL 
            search query of the point cloud at each output DEM pixel.  If the 
            result set for each pixel does not have at least MINPOINTS, NULL 
            values will be written to the output DEM pixel.
          
 
Parameters:
                        ALGORITHM
                         Description
                       
              
                This parameter provides numerous methods to compute the 
                output radius value for a given latitude, longitude and map grid 
                point.  Any number of methods can be specified by enetering
                a comma-delimited lisf of the method names.
              
               
                 
                     DEM Data Value Output Function Options
                  
                  
                    | Name | 
                    Parameters | 
                    Description | 
                  
                  
                    | AverageRadius | 
                    None | 
                    
                      For all control points found in the RADIAL and/or 
                      NEARESTNEIGHBOR kd-tree search, computes the average radius
                      value (the average Euclidean distance of all points from the surface
                      to the center of the body).
                     | 
                  
                  
                    | MaximumRadius | 
                    None | 
                    
                       Computes the maximum radius (in meters) of the control points.
                     | 
                  
                  
                    | MinimumRadius | 
                    None | 
                    
                      Computes the minimum radius (in meters) of all control points.
                     | 
                  
                  
                    | MedianRadius | 
                    None | 
                    
                    Computes the median radius (in meters) of all control points.
                     | 
                  
                  
                    | StandardDeviationRadius | 
                    None | 
                    
                      Computes the standard deviation (in meters) of the radii of
                      the control points.
                     | 
                  
                  
                    | MaximumDistance | 
                    None | 
                    
                    Computes the maximum surface distance (in meters) of all control points
                    with respect to the latitude, longitude coordinates of the central pixel.
                     | 
                  
                  
                    | MinimumDistance | 
                    None | 
                    
                    Computes the minimum surface distance (in meters) of all control points
                    with respect to the latitude, longitude coordinates of the central pixel.
                     | 
                  
                  
                    | MedianDistance | 
                    None | 
                    
                    Computes the median surface distance (in meters) of all control points
                    with respect to the latitude, longitude coordinates of the central pixel.
                     | 
                    
                    
                      | AverageDistance | 
                      None | 
                      
                      Computes the average surface distance (in meters) of all control points
                      with respect to the latitude, longitude coordinates of the central pixel.
                       | 
                    
                  
                    | StandardDeviationDistance | 
                    None | 
                    
                    Computes the standard deviation (in meters) of the surface distance of
                    all control points with respect to the latitude, longitude coordinates
                    of the central pixel.
                     | 
                  
                  
                    | FrankeNelsonRadius | 
                    None | 
                    
                     Computes the radius of the control points (in meters)
                     using the Franke-Nelson method.
                     | 
                  
                  
                    | ShepardsRadius | 
                    None | 
                    
                    Computes the radius of the control points (in meters)
                    using Shepard's weighted algorithm.
                     | 
                  
                  
                    | NaturalNeighborRadius | 
                    None | 
                    
                    Computes the radius of the control points (in meters)
                    using the Nearest Neighbor interpolation algorithm.
                     | 
                  
                  
                    | TypeCount | 
                    None | 
                    
                    Returns the total number of pixels in the point collection. It
                    additionally applies a signed (+/-1) value to indicate
                    if the FLANN (Fast Library for Approximate Nearest Neighbors) search type
                    was nearest neighbor (-1) or radius (+1).
                     |