The influence of Quality Parameters during SURE processing
The GSD - Ground Sampling Distance in SURE defines the size of a DSM raster cell.
In SURE the user has the option to obtain a product having different resolutions due to several Processing Quality Levels.
The step from one resolution level to next one will represent a quarter of the initial resolution level, meaning that a product generated with a Quality High will have a duplicated GSD compared to the Ultra Quality.
The main role of the Quality Parameters it is a processing quality drop-down, which can be explained by the examples below.
Example of the GSD up-sampling in regards to the Processing Quality in SURE
|Processing Quality Levels (Pyramid Levels) processing quality drop-down|
Quality example for a project with a 5cm original GSD
GSD for Ultra Quality
GSD for High Quality
GSD for Medium Quality
GSD for Low Quality
For low flight overlaps for example 60/30, the GSD of the DSM will be doubled by default. For this case the Dense Matching will be performed at the selected Quality level. Moreover, the DSM / TrueOrtho output will have a duplicated GSD in addition to the Quality Level.
By duplicating the size of the raster cell a higher redundancy of having a point falling into the raster increases and the fact that the cell is considered valid during rasterization is leading to completeness in the DSM.
The GSD multiplicator is not affecting the 3D Mesh/ Mesh texturing. These products are generated based on the Quality Levels chosen for the generation of Dense Clouds.