- a) Photo / Topo Coverage:
A rectangular tiling system of images is standard in LUPMIS to enable easy access and archiving:
- The standard area size of images at high resolution is 2 x 1 km (width 2 km, height 1 km). For lower resolution, image 'overviews' have area sizes of 6 x 3, 12 x 6, 24 x 12 km.
- All images are 'anchored' with their left bottom (SW) corner at a round km-grid in UTM 30.
- This 'anchor' determines the first part of the file name. After that number, the file name includes the year, size and resolution, all separated by _. Additional remarks about the processing might be added at the end.
- All images of one set (same year, same resolution) are stored in one folder under the photo folder of the District.
Example: 6780789_2010_2x1_40: At SW corner of 678000 / 789000 with an area of 2 x 1 km and a resolution of 40 cm, of the year 2010.
The full syntax of all image files (satellite images, aerial photographs, topo sheets) can be viewed Drawing Tools > Utilities > Photo / topo coverage, also shown below:
You can also enter a filename of an image, and have its extent displayed in GIS or in an Internet map browser.
If the raw source file(s) are very large or in a different projection, tiles can be created automatically through LUPMIS (see Chapter 188.8.131.52: Cut to tiles).
If work is carried out in smaller scales (e.g. for Structure Plans or SDF), images are better re-sampled to cover larger areas. These image 'overviews' can be automatically created throught LUPMIS (see Chapter 184.108.40.206: Merge tiles).
This Tool 'Coverage' also has a quality-control feature of checking, if the file name of the images (satellite images or aerial photographs) follows the explained naming standards:
If the result is as below, everything is ok:
Background of this function are frequent observations, that files were wrongly (manually) named and can therefore not be found in the system.