A color composite can be directly created by typing one of the following expressions on the command line of the Main Window:
|
OUTMAP |
= |
MapColorComp(MapList, range1, range2, range3) |
|
OUTMAP |
= |
MapColorCompLinear(MapList, range1, range2, range3) |
|
OUTMAP |
= |
MapColorCompHistEq(MapList, range1, range2, range3) |
|
OUTMAP |
= |
MapHeckbert(MapList, NrColors) |
|
OUTMAP |
= |
MapColorComp24(MapList) |
|
OUTMAP |
= |
MapColorComp24(MapList, range1, range2, range3) |
|
OUTMAP |
= |
MapColorComp24Linear(MapList) |
|
OUTMAP |
= |
MapColorComp24Linear(MapList, range1, range2, range3) |
|
OUTMAP |
= |
MapColorComp24HistEq(MapList,range1, range2, range3) |
|
OUTMAP |
= |
MapColorComp24HSI(MapList) |
where:
|
OUTMAP |
is the name of your output color composite. |
|
MapColorComp |
is the command start the Color composite operation using linear stretching. |
|
MapColorCompLinear |
is the command start the Color composite operation using linear stretching. |
|
MapColorCompHistEq |
is the command to start the Color composite operation using histogram equalization. |
|
MapHeckbert |
is the command to start the Color composite operation using the Heckbert dynamic algorithm. |
|
MapColorComp24 |
is the command to start the 24-bit Color composite operation using linear stretching. |
|
MapColorComp24Linear |
is the command to start the 24-bit Color composite operation using linear stretching. |
|
MapColorComp24HistEq |
is the command to start the 24-bit Color composite operation using histogram equalization. |
|
MapColorComp24HSI |
is the command to start the 24-bit Color composite operation using hue, saturation, and intensity. |
|
MapList |
is the name of an existing map list which contains 3 raster maps with the Image domain, or the definition of a map list as: |
|
range1..3 |
for each band, the intervals of input values to be used as min:max or as perc |
|
min:max |
minimum and maximum value determining range of input values, e.g. 20:200; integer values between 0 and 255. |
|
perc |
percentage of input values to be ignored on both sides of the maps' histogram during linear stretch or histogram equalization; 0 � real value < 50. When no ranges are specified for the MapColorComp24 or MapColorComp24Linear commands then all input values are used, i.e. no stretching. The MapHeckbert and the MapColorComp24HSI commands always use all input values. |
|
NrColors |
For Dynamic (Heckbert) color composites: the number of colors present in the output map (2-255). |
All maps in the input map list must have the same georeference.
When the definition symbol = is used, a dependent output map is created; when the assignment symbol := is used, the dependency link is immediately broken after the output map has been calculated.
Examples:
A complete expression to calculate a color composite of bands tm4, tmb3, and tmb2, using linear stretching and ignoring 1% of all input values, might thus read:
|
OUTMAP |
= |
MapColorComp(mlist(tmb4,tmb3,tmb2),1,1,1) |
A complete expression to calculate a dynamic color composite of bands tm4, tmb3, and tmb2, using 200 colors, might thus read:
|
OUTMAP |
= |
MapHeckbert(mlist(tmb4,tmb3,tmb2),200) |
See also: