Block of ADS40/80/100 Images
The ADS40 processing workflow involves GPro and ORIMA software (by Leica, Switzerland) along with PHOTOMOD system.
GPro version 3.2.1 and ORIMA version 9.1 should be used.
Images of Level 1, created in GPro software by the images of Level 0 preprocessing level,
should pass block adjustment in ORIMA software, and then may be added to PHOTOMOD project.
Project processing is carried out as follows:
Workflow of ADS40 data processing using PHOTOMOD system
- After data has been loaded from MM40 block to the workstation, GPro software is used to create images of Level 0 and
measure tie points there automatically
- ORIMA program is used to adjust block of Level 0 images (with or without ground control points, in latter case using
exterior orientation parameters measured on board)
- GPro program is used to create images of Level 1 using adjustment results
- Level 1 images are added to PHOTOMOD project and further processed in PHOTOMOD to create output products.
Creation of ADS40 project in PHOTOMOD
If the project contains at least three points with known ground coordinates, which will be measured
on stereopairs, you may use local coordinate systems of Cartesian (left or right) type. Otherwise process the project
in Projected (UTM etc.) or Topocentric horizontal types of coordinate system.
Such restriction comes out of the coordinate system Local Space Rectangular (LSR) in which exterior orientation
parameters of ADS 40 sensor are supplied.
Adding data to the project
Since project adjustment is performed by external software, it is unreasonable to add a big number of ADS40 images to
one PHOTOMOD project. We suggest using one of the following project layouts:
- add (into one strip, to create stereopair) nadir and one of oblique images (for the latter, the image acquired forward
along pass is preferable, since it allows to get higher ratio of survey basis to height, which is important for DEM creation);
while orthoimage is better to build from nadir image;
- add (into one strip, to create stereopair) two oblique images; thus you achieve the highest ratio of survey basis to
- add two oblique images into one strip, and nadir image into another one. Thus first two images produce stereopair with
higher ratio of survey basis to height, which is used for DEM building. Then orthoimage is created from nadir image and
DEM built from oblique images.
The following initial data files are used when adding of ADS40 images to PHOTOMOD project:
- metadata file (support-file, *.sup). The file contains parameters of LSR coordinate system, and also parameters of
correspondence between coordinates "on-ground" in LSR coordinate system and coordinates on Level 1 image;
- file with sensor interior orientation parameters (*.cam);
- file with exterior orientation parameters (*.odf);
- raster image; since the software which is used for input data pre-processing for PHOTOMOD system stores reduced copies
of initial images in separate files, one should make sure that the image to be added to the project has initial resolution.
Such files have names like *_0_0.tif.
Processing of this type of project includes three stages: Block forming, Aerial triangulation, and Block processing.
On Block forming stage images are added to the project in the same manner as for space scanner images, including
On Aerial triangulation stage tie points are measured on stereopairs. Ground control (GCP) and check points may be
measure as well, they are used for verification of adjustment results and validity of created PHOTOMOD project.
Besides, GCP are necessary if the project has coordinate system of Cartesian (left or right) type.
When switching to the Processing stage, a report on adjustment results is shown.
Further project processing is carried out in the same way as with other types of projects.