Creating an image service using Applanix DSS Airborne Sensor data

Legacy:

ArcGIS 10 is the last release of the stand-alone ArcGIS Image Server product. The image service definition (.ISDef) has been replaced by an improved geodatabase data model—the mosaic dataset—which can be published as an image service using the ArcGIS Server Image extension.

Data collected using the Applanix DSS Airborne Digital Sensor System can be ingested directly into ArcGIS Image Server. This sensor works ideally with ArcGIS Image Server because the metadata collected at the same time as the imagery, such as the georeferencing information, can be directly read, and with the addition of a DEM, an orthorectified image service definition can be created.

Calculate the Konrady coefficients

The Konrady coefficients define the radial lens distortion and are expressed as three values. There is more than one way to calculate and use these values. Sometimes these values are provided in the camera's calibration report; however, these may not be the values required. The camera's calibration report will provide you with the radial lens distortion values that can be used to calculate the required Konrady coefficients. Please use the Excel spreadsheet to assist in computing these values. By default, this spreadsheet can be found in C:\Program Files\ArcGIS\Image Server\XADefs\RPDef Generators and is called Konrady coefficients computation.xls.

The Konrady coefficient values are used when adding aerial imagery, such as from the Applanix DSS camera.

Steps:

1. Open the Camera Calibration certificate report.

   This is generally a PDF in the CameraFiles folder. Make sure you open the file for the correct camera lens size such as the 60 mm VIS lens.

2. Open the Konrady coefficients computation.xls.

   This is located in <Install Directory>\ArcGIS\ImageServer10.0\XADefs\RPDef Generators.

3. Enter the Radial Distance (in millimeters [mm]).
4. Enter the corresponding Radial Distortion (in microns) values.

   These may be provided in pixels and microns (µm), be sure to enter the micron values.

   The Konrady coefficients will be calculated within the G column.

5. Record the K0, K1, and K2 values.

Create the image service definition

Steps:

1. Open ArcMap.
2. Click the Image Service drop-down menu on the Image Service Definition Editor toolbar, point to Advanced, then click New Service Definition.

   The Image Service Definition dialog box is displayed.

3. Click the Service definition browse button , navigate to the location where you want to create the image service definition, type the name in the File name text box, then click Save.
4. Click the Spatial reference browse button and select a spatial reference system provided in the ArcGIS Coordinate Systems folder.

   Optionally, if you've used this dialog box before, you can select the drop-down arrow and select a spatial reference you've selected before.

   This is the spatial reference system used for the image service definition and is not necessarily the same as that of each raster dataset that will be added. The spatial reference should be selected such that no coordinate system boundaries exist within the extents of the required image service definition.

5. Optionally, click the Service type drop-down arrow and select a service type.

   Normally, the Color (RGB) service type will be adequate. This is used for a three-band image. There may be times when you need to use 4-Band (RGBI). If you use Custom, be sure to specify the remaining parameters.

6. Click OK.

   The new image service definition is added to the table of contents. It contains a group layer with an empty Footprint layer.

Add the images

Steps:

1. Click the Image Service drop-down menu on the Image Service Definition Editor toolbar, point to Advanced, then click Add Raster Dataset.

   The Select Raster Type dialog box opens.

2. Double-click the Orthorectification folder.
3. Click Applanix-DSS eo_std file and click OK.
4. Click the Applanix-DSS eo_std.txt file browse button .
5. Click the Files of type drop-down arrow and click All files (*.*).

6. Navigate to the EO folder and click the appropriate file.

   There may be more than one exterior orientation (EO) file in this folder. For example, there may be an eo_ellipsoid.txt and an eo_orthometric.txt file. Be sure to choose the correct file, relative to the height values in your DEM.

   Note:

   Check that the image file ID numbers in this file match the ID numbers in the Input image location. If not, edit the ID numbers in this file.

7. Click Open.
8. Click the Input image location browse button .
9. Navigate to and click the folder containing the image files, such as Photocorr, and click OK.
10. Optionally, click the Overviews location browse button , navigate to and click the folder containing the overview files, then click OK.

11. Click OK on the Import Applanix eo_std prj files dialog box.

    The Applanix eo_std Project dialog box opens.

12. Open the Camera Calibration certificate report you opened to calculate the Konrady coefficients.
13. Find the focal length and x,y coordinates of the principal point measured from the image center (PPA X and PPA Y).

    These may be identified as

    Focal Length =

    PPA X =

    PPA Y =

14. Enter these values on the Applanix eo_std Project dialog box.

    Caution:

    Be sure these values are entered in microns (µm).

    If these values are provided in millimeters, you need to multiply them by 1,000 to get the value in microns (1 mm = 1000 μm). For example, a focal length of 60.184 mm will equal 60,184 μm. A PPA X of -0.225 mm will equal -225 μm.

15. Enter the Konrady coefficients values—K0, K1, and K2—you calculated earlier.

16. Click the Save camera file browse button.

    It is recommended that you save your camera file so you can use it again without reentering the information. It's also good to keep in case you've entered a value incorrectly.

17. Navigate to the location where you want to save the calibration file, type a file name, then click Save.

    The next time you use this dialog box, click the Load camera file browse button to select this file you've saved.

18. Click the Orthorectification Parameters tab.
19. Select the correct Spatial Reference System.
20. If using a DEM, click the Terrain type drop-down arrow and click DEM.
21. Enter the Average Z value for this DEM.

    Note:

    You must enter this value even if you've defined a DEM.

    To identify the correct Average Z value, open the DEM in ArcGIS. Be sure statistics have been calculated. Open the properties and scroll to the Statistics section. Use the mean value.

22. Optionally, edit the other parameters.

    Learn about the orthorectification parameters

23. Optionally, click the Enhancement Parameters tab and edit the parameters.

    Learn about the enhancement parameters

24. Click OK.

    The images are added to the image service.

Build the image service definition

You need to build the image service definition to derive the service parameters—such as pixel size ranges and the boundary—and extract metadata. Once generated, you can preview the imagery.

Steps:

1. Click the Image Service drop-down menu on the Image Service Definition Editor toolbar, point to Advanced, then click Build.

   The Build Options dialog box is displayed.

2. Accept the default checked options and click OK.

   The Service Editor-Reporter window displays the progress of various build options. Once completed, the group layer in the table of contents will be updated. A Boundary and Preview layer will be added.

Recompute the footprints

The original Footprints need to be updated, as they were only estimates when they were first created. Now that the pixel information has been calculated, they can be updated.

Steps:

1. Right-click the Footprint layer in the table of contents, point to Recompute Footprint, then click By Geometry.

   The Recompute Footprint By Geometry dialog box is displayed with default values for each of the parameters.

2. Click the Image type drop-down arrow and click either Orthorectified image in flat terrain or Orthorectified image in hilly terrain.

   Learn about the parameters to recompute footprints based on geometry

3. Click OK.

   The Footprint polygons will be updated.

Recalculate the boundary

The Boundary needs to be updated because the Footprints were modified.

Steps:

1. Click the Image Service drop-down menu on the Image Service Definition Editor toolbar, point to Advanced, then click Build.

   The Build Options dialog box is displayed.

2. Check Create service boundary.

   This should be the only option checked.

3. Click OK.

Optimize the service with service overviews

Service overviews are preprocessed, low-resolution raster dataset tiles covering the entire service. These overviews speed up the display of imagery at lower resolutions, because they are used when clients are viewing large portions of the image service definition at a low resolution. With service overviews, a lower-resolution copy of the data appears quickly while viewing entire datasets. When you zoom in, levels of finer resolutions are drawn and the performance is maintained because the service transmits successively smaller areas. The server chooses the most appropriate service overview based on the display scale. Without service overviews, the entire dataset would have to be processed on the fly. Service overviews enable you to create an overview of the complete image service definition for viewing.

Steps:

1. Click the Image Service drop-down menu on the Image Service Definition Editor toolbar, point to Advanced, point to Optimize, point to Service Overviews, then click Define.

   The Service Overview Parameters dialog box is displayed. You can modify the parameters or accept the defaults.

2. Click OK.

   Once the service overviews have been defined, the Image Service Editor message box displays.

3. Click OK.
4. Click the Image Service drop-down menu on the Image Service Definition Editor toolbar, point to Advanced, then click Build.
5. Check Generate Derived Images.
6. Check Compile service.
7. Click OK.

   The Service Editor Report window will display a message when the build is completed and the service overviews have been added to the image service definition.

You can now publish the image service.