Case Study on Point Data - Open Source Geospatial Tools: Applications in Earth Observation - page 317

--topo
Use topographic elevation ( height height above ground).
-r 50
Number of rows within a block is 50.
--overlap 10
Size (in bins) of the overlap between processing blocks is 10.
--in NATURAL_NEIGHBOR
The interpolator to be used.
-f GTIFF
Format of output raster dataset is GeoTIFF.
-b 1
output pixel size is 1 m.
-i LiDAR_10m_pmfmccgrd_h.spd
Name of input SPD point dataset.
-o LiDAR_1m_pmfmccgrd_dtm.tif
name of output raster dataset.

To provide a visualization of the raster surfaces, a hill shade model is then calcu-
lated as shown in Fig. 18.2 using the utility gdaldem (see Sect. 10.6 ) .

gdaldem hillshade LiDAR_1m_pmfmccgrd_dtm.tif
→

LiDAR_1m_pmfmccgrd_dtm_hs.tif

gdaldem hillshade LiDAR_1m_pmfmccgrd_chm.tif
→ LiDAR_1m_pmfmccgrd_chm_hs.tif

(a) (b)

Fig. 18.2 Hillshade of the, a digital terrain model (DTM), b canopy height model (CHM)