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ENVIROI

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


AddGeometry

AddPixels

AddThreshold

AddVectorRecords

ClearGeometry

ClearPixels

ClearThresholds

ClearVectorRecords

Close

Dehydrate

GetExtent

GrowRegion

Hydrate

PixelAddresses

Pixelate

PixelCount

Revert

Save

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, Service Pack 1

Added Dehydrate method

ENVI 5.4

Added Hydrate method

API Version


3.2

See Also


ENVI function, ENVI::OpenRaster, ENVIRasterLayer::AddROI, ENVI::OpenROI, ENVIVectorAttributeToROIsTask, ENVIVectorRecordsToSeparateROITask, ENVIVectorRecordsToROITask



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