cnetadd

This application adds Level 1 and Level 2 images to an existing ISIS Control Net file. It takes in an input Control Net CNET and a list file ADDLIST which contains filenames of all the images to be added to the Control Net. The application adds the images to the network depending on the Retrieval options. The resulting output Control Net is placed in the user specified output file ONET. All other Control Net configurations remain unchanged.

FROMLIST contains the list of all the images that are part of the input Control Net. This input parameter is optional with Control Nets generated by applications such as "seedgrid" which will contain only lat/lon but no other Control Measures. However, FROMLIST is required if the RETRIEVAL option is REFERENCE (described herein) where the lat/lon's are obtained from the FROMLIST cubes.

The application checks each image in the ADDLIST for all the Control Points in the input Control Network as to whether it can be added to any given Control Point. If the image already exists for the Control Point, it is skipped. Otherwise, it is checked to see if the Control Point's location is within the latitude/longitude (lat/lon) boundaries of the image, and adds the image measures if it is.

TOLIST is an optional output list which contains the list of all images in the output Control Net. If TOLIST is defined then FROMLIST is required to make the output list complete. Otherwise the TOLIST will contain only the new images from ADDLIST added to the Control Net.

The images in the FROMLIST and ADDLIST must be available for the program to open. All the PVL log information such as duplicate serial numbers common to FROMLIST and ADDLIST, images added, images omitted and Points modified are placed in LOG file if specified.

MODIFIEDPOINTS is an optional output parameter that allows the user to create a list of the modified points in the final Control Net.

The program has four additional Options or parameters: POLYGON, RETRIEVAL, EXTRACT, and DEFILE. If the POLYGON option is enabled, this optimization will prune points that fall outside the latitude/longitude bounding box of the polygon for the image being added. By performing this check up front, no expensive camera calculations to find a Point's location on an image will be performed for points that fail this test. In most cases, the vast majority of points fall outside of any given image during the adding process, so performance gains can be orders of magnitude. IMPORTANT NOTE: this optimization requires that all images have had "footprintinit" run beforehand in order to find the image polygons.

The Control Point's location (lat/lon) is retrieved from either the REFERENCE (default) or POINT preference of the RETRIEVAL parameter. If REFERENCE is chosen, the lat/lon is calculated from the reference camera information of the corresponding images in FROMLIST. If POINT is chosen, the lat/lon is taken directly from the information attached to the Control Point. The lat/lon is then used to get the Line and Sample of the point on the image. IMPORTANT NOTE: the POINT option is meant for Control Networks built using "seedgrid" because this program attaches the lat/lon information to the points. If you use this option on networks with Control Points that do not have this information, those points will be ignored.

The EXTRACT parameter allows the user to define what goes into the ONET. If ALL (default)is specified, then the entire input Control Net with the modified points will be written out to the output Control Net. If MODIFIED is specified, then only the modified Points(points which has the images from the ADDLIST added to it) will be extracted to the output.

DEFFILE could be specified to validate measures (images). If the image being added to a particular point fails the validation test then the Measure is set to be Ignored. Following are the different options which could be specified in the DEFFILE.The application will validate the measure for specified properties. These properties are optional and the DEFFILE can have different combinations of these properties. The DEFFILE should be in the format shown below:

Measures are added if a Point is locked. But if the Point is locked and Apriori source is "AverageOfMeasures" then the measures are not added to the Control Point. This is because the Point being locked, it cannot be be updated for lat/lon values, so newly added measures did not contribute to the average that had been previously computed for at the point level.