DSM Metainformation Layers
Apart from the DSM product itself, SURE can generate additional raster layers which store DSM Metainformation. These items are written as tif images with a one-to-one correspondence to the DSM tif tiles and they can only be generated if the DSM is also produced. The Metainformation layers also provide insights to the quality of the observations in the DSM.
DSM Height Colored
This image has its pixels color-coded in a particular way depending on their corresponding height values. The repetitive color bands pattern facilitates the visualization of subtle height differences or slopes.
DSM Point Color
Each pixel retains the RGB values of the original point that delivered the Z value at the respective position.
DSM Point Color Interpolated
Each pixel retains the RGB values of the original point that delivered the Z value at the respective position plus the interpolated pixels will be textured in black.
This layer displays a measure of the local height variation across a mask of 3x3 pixels. Small or nil values are expected in flat areas, whereas larger values indicate an abrupt change in elevation (e.g. near building edges).
DSM Cell Point Count
The pixels in this image retain the number of original 3D points that were created inside the respective raster cells. The layer can be interpreted as a visibility measure because it basically indicates how many times the input images could triangulate points in the respective pixels.
DSM Cell Standard Deviation
This product stores per pixel the standard deviation in terms of elevation for the population of points that were generated inside the respective raster cell. This can be a good indicator of the reliability of the height measurement that ended up in the DSM product.
DSM Model Count
This image stores the number of the stereo models that generated the points from which the elevation measurements in the DSM were taken.
DSM Binary Mask
Every pixel, where an actual height measurement was available, is represented as white (255 or maximum intensity), whereas the pixels, that were either interpolated or left empty, are represented as black (0 or minimum intensity).
DSM Distance Mask
For each raster cell of the DSM that does not contain a measurement (including interpolated pixels), the euclidean distance to the closest pixel with a valid measurement (originating in a 3D point) is stored.