Modification of the Area Geometry

Modify Geometry of Area

The geometry of a raster database, for example, the database bounds (lower-left corner and upper-right corner), as well as the resolution, can be changed by clicking Edit > Modify Geometry of Area). The following options are available:
Extract Data
This option offers the possibility to extract data of a specified sub-area. This can be useful if a large topography database is resized to keep only the relevant part of the database.

Figure 1. The Database Aperture dialog.
Database Bounds
Lower-left and upper-right corner of the database. These coordinates can be changed to obtain a smaller area. Press Reset to reset the coordinates to their original values.
Further Settings
The number of columns and lines of the database can be changed. A change of these parameters influence the coordinates of the upper right corner in the upper section. Resolution and covered area are displayed for information only and cannot be changed.
Increase number of columns and lines
The raster database can be enlarged by increasing the number of columns and / or lines.

Figure 2. The Enlarge Prediction Area dialog.
Change resolution
The resolution of the database can be increased or decreased by an arbitrary factor.

Figure 3. The Change resolution dialog.
Move lower-left corner (move data)
The entire raster database can be shifted to another location by changing the lower-left corner.

Figure 4. The Move lower-left corner dialog.

Modify Data in Area

To modify data in an area, click Edit > Modify Data in Area. The following options are available:

Interpolate data
Missing pixel values can be interpolated from the values of the surrounding pixels.
Filter data
Raster data can be filtered with arithmetic or median filter. The order of the filter can be specified.

Figure 5. The Filter dialog.
Smooth data
Pixel data can be beautified by increasing the resolution and applying a filter afterward. This can be useful for presentation plots. You can specify the raster factor for increasing the resolution and the filter order.

Figure 6. The Smooth dialog.
Delete data
Selecting this option erases all data contained in the raster database. This means all pixels are set to “not compute”.
Assign values to pixels to borders
Pixels at the border of the raster database, which are “not computed” can be padded with the value of the next available pixel value of the same column (for pixels at the top or the bottom) or line (for pixels at the left or right side). This is especially useful if a topography database needs to be extended and no additional data is available.