ENVIROI
This is a reference to an ROI object.
Example
; Launch the application
e = ENVI()
; Open an ENVIRaster
file = FILEPATH('qb_boulder_msi', ROOT_DIR=e.ROOT_DIR, $
SUBDIRECTORY = ['data'])
raster = e.OpenRaster(file)
; Create an ROI
roi1 = ENVIROI(NAME='Region 1', COLOR='Blue')
; Print the ROI properties
Print, roi1
IDL prints:
ENVIROI <244676>
COLOR = 0, 0, 255
NAME = 'Region 1'
N_DEFINITIONS = 0
See More Examples.
Syntax
Result = ENVIROI([, Keywords=value])
Methods
Properties
Properties can be set as keywords to functions during creation, or retrieved or changed using the "." notation after creation.
COLOR
Set this property to a string or RGB vector that specifies the color of the ROI. If this property is not set, then it will use a default color.
The following table lists the single characters that you can use as the color modifier in either the COLOR property or the Format string argument. You must use the lower-case character.
|
Color Name |
Character |
|---|---|
|
Blue |
b |
|
Green |
g |
|
Red |
r |
|
Cyan |
c |
|
Magenta |
m |
|
Yellow |
y |
|
Black |
k |
|
White |
w |
When setting the COLOR property, you can also use any of the string values defined by the !COLOR system variable, as shown in the following image:
NAME
Use this property to specify a named variable that contains a ROI name. If this property is not set, then it will use a default name that is currently not in use, starting with Region 1.
More Examples
This example shows how to get the properties of multiple ROI records within a single ROI file:
; Launch the application
e = ENVI()
; Open an ENVIRaster
file = FILEPATH('qb_boulder_msi', ROOT_DIR=e.ROOT_DIR, $
SUBDIRECTORY = ['data'])
raster = e.OpenRaster(file)
; Open a multi-part ROI
ROIFile = FILEPATH('qb_boulder_roi.xml', $
ROOT_DIR=e.ROOT_DIR, SUBDIRECTORY = ['data'])
rois = e.OpenROI(ROIFile)
; Print the ROI properties
For i=0, n_elements(rois)-1 do $
Print, rois[i]
IDL prints:
ENVIROI <231489>
COLOR = 240, 240, 0
NAME = 'Disturbed Earth'
N_DEFINITIONS = 1
ENVIROI <231490>
COLOR = 255, 0, 0
NAME = 'Bright Roof'
N_DEFINITIONS = 1
ENVIROI <231491>
COLOR = 29, 29, 255
NAME = 'Water'
N_DEFINITIONS = 1
Also see How do I process the pixels within a region of interest (ROI)?
Version History
|
ENVI 5.1 |
Introduced |
|
ENVI 5.3.1 |
Added Dehydrate method |
|
ENVI 5.4 |
Added Hydrate method |
API Version
4.2
See Also
ENVI function, ENVI::OpenRaster, ENVIRasterLayer::AddROI, ENVI::OpenROI, VectorAttributeToROIs Task, VectorRecordsToSeparateROI Task, VectorRecordsToROI Task