Внешнее ориентирование

The source image can be described using various models. There are 7 models for image orientation in OrthoMap:

• Polynomial (Conformal).

• Polynomial (Affine).

• Polynomial second order.

• Frame (central projection);

• Simple Dynamic;

• Panoramic Static;

• Panoramic Dynamic;

In order to achieve maximal accuracy in orthorectification it is necessary to select the image model correctly. The following table shows default settings of orientation model for different types of cameras (these settings can be changed by operator):

Camera type Orientation type (model)

KVR-1000 Panoramic Dynamic

TK-350 Frame

KFA-1000 Frame

MK-4 Frame

Landsat-TM Panoramic Dynamic

Unknown Frame

The transформатion parameters include static (frame image) and dynamic parts. All these parameters are determined during exterior orientation. In case of insufficient amount of control points it is possible to determine only static (frame) image parameters.

The following parameters are determined during exterior orientation:

* coordinates of the point of photography;

* 3 angles of shooting;

* 6 dynamic parameters.

Select "Orientation" item from "Process" menu. If control points file is present, Exterior orientation window is opened.

The window contains a table of control points. Each point can be included into or excluded from the process of orientation by left-clicking in appropriate "On/Off" cell. To start the process of orientation press "Solve" button . Resulting accuracy (RMS error) of orientation is then displayed in "Accuracy of orientation" field. The column "Rxy" in the control points table shows RMS for each point. After completion of the process of orientation the resulting orientation parameters can be viewed in the Inформатion window using "Info" item from "File" menu or "Project inформатion" button from tools palette. It is also possible to store the orientation accuracy report in a file by pressing button. Before starting the process of orthorectification the active project must be saved for the resulting orientation parameters to be stored in the project file.

Трансформирование снимковIdh_Ortho

If the accuracy of exterior orientationIDH_ext is acceptable then it is necessary to save the parameters in project file by pressing "Save Project" button.

To start the module of orthorectification with current project select "Rectification (Ortho)" item from "Process" menu. If exterior orientationIDH_ext not solved then module rectify.exe will not start. If project was changed then you will be asked to save project before start of Rectify module.

The module works with active project. The module window displays the following inформатion:

• source image file name;

• output file name;

• number of columns and rows of output file;

• grid steps in meters along X and Y axes for output file.

To start the process of orthorectification press "Start" button. Progress indication window displays elapsed processing time, approximate remaining processing time and percentage of process completion. To interrupt the process press "Cancel" button. If DEM is not specified when starting the process, transформатion will be performed to mean plane with the height specified in the active project with appropriate message displayed in message window.