Raster Data Interpretation
This allows for the display of data in a variety of ways common to most image processing packages. The resultant dataset can then be exported as a geotiff for vector interpretation in a GIS package. Each display type is discussed below.
Display Type
This gives options for different types of maps. They are as follows:
- Single Color Map - displays a single band of data by mapping its values to a color map or color table.
- Contour - This has the same options as the single color map, but displays the data using contours instead.
- RGB Ternary - displays three bands, one red, one green and one blue. Because of this, no color map can be chosen, and now three bands must be chosen.
- CMYK Ternary - displays three bands, one cyan, one magenta and one yellow. As before, no color map can be chosen, and now three bands must be chosen.
Data Bands
The bands to be displayed are chosen here.
Histogram Stretch
The choice of how to map the data is chosen here. The options are:
- Linear with Percent Clip - compacts a % of the outliers of the data, as chosen by the user.
- Histogram Equalisation - gives all colors the same amount of data samples, so that maximum change is seen in the map)
The user must press to apply button once the setting is changed.
Color Bar
Here you can choose the color bar to map the colors with.
Sunshade
This option applies a sunshade algorithm to the data, with the color overlay being chosen in the Display Type step. Options are:
- Sun Angle - This is chosen by clicking on a small circular map. A blue dot denotes the sun's azimuth and elevation.
- Sunshade Detail - controls how much sunshade detail is present. Decrease this to increase the detail.
- Light Reflectance - controls the light reflectance of the surface.
Save Geotiff
Use this to save your final maps as a Geotiff. This will also save two color bars (one vertical and one horizontal) or a ternary color bar. The size of the color bar relates to how big you wish it to be on the paper map.
References
Horn, B. K. P., 1981. Hill shading and the reflectance map. Proceedings of the IEEE, 69(1), 14-47. doi:10.1109/PROC.1981.11918