A collection of tasks that wrap ENVI doits for color space tranforms. See below for more details and examples for how to run each task.
These examples assume that you have not placed the tasks in ENVI's custom code folder and are running from IDL with this repository added to IDL's search path. For the proper way to install the tasks, see https://github.com/envi-idl/TaskAndExtensionInstallGuide.
For specific details about all task parameters for the tasks listed below, view the associated .task file in this folder.
In order to perform a correct, forward color transform on the data (to HLS or HSV spaces), the input raster must have data values between 0 and 255. To accomplish this, with IDL you can use of the stretch rasters listed below which also provide links to the documentation. In the examples, the ENVILinearPercentStretchRaster is what is used.
This tasks wraps the ENVI Classic rgb_trans_doit and converts an image from red/green/blue (RGB) to hue/lightness/saturation (HLS). The below example creates an HLS raster from RGB.
; Start the application
e = ENVI()
; Load our extra tasks
xtTasksInit
; Open an input file
File = Filepath('qb_boulder_msi', Subdir=['data'], $
Root_Dir=e.Root_Dir)
Raster = e.OpenRaster(File)
; Process a spectral subset
Subset = ENVISubsetRaster(Raster, BANDS = [0,1,2])
; Stretch our data so that we are in 0-255 RGB space
Stretched = ENVILinearPercentStretchRaster(subset)
; Get the task from the catalog of ENVITasks
Task = ENVITask('XTRGBtoHLSRaster')
Task.INPUT_RASTER = Stretched
Task.OUTPUT_RASTER_URI = e.GetTemporaryFilename()
Task.Execute
; Get the collection of data objects currently available in the Data Manager
DataColl = e.Data
; Add the output to the Data Manager
DataColl.Add, Task.OUTPUT_RASTER
; Display the result
View1 = e.GetView()
Layer1 = View1.CreateLayer(Subset)
Layer2 = View1.CreateLayer(Task.OUTPUT_RASTER)This tasks wraps the ENVI Classic rgb_trans_doit and converts an image from red/green/blue (RGB) to hue/lightness/saturation (HLS). The below example creates an HSV raster from RGB.
; Start the application
e = ENVI()
; Load our extra tasks
xtTasksInit
; Open an input file
File = Filepath('qb_boulder_msi', Subdir=['data'], $
Root_Dir=e.Root_Dir)
Raster = e.OpenRaster(File)
; Process a spectral subset
Subset = ENVISubsetRaster(Raster, BANDS = [0,1,2])
; Stretch our data so that we are in 0-255 RGB space
Stretched = ENVILinearPercentStretchRaster(subset)
; Get the task from the catalog of ENVITasks
Task = ENVITask('XTRGBtoHSVRaster')
Task.INPUT_RASTER = Stretched
Task.OUTPUT_RASTER_URI = e.GetTemporaryFilename()
Task.Execute
; Get the collection of data objects currently available in the Data Manager
DataColl = e.Data
; Add the output to the Data Manager
DataColl.Add, Task.OUTPUT_RASTER
; Display the result
View1 = e.GetView()
Layer1 = View1.CreateLayer(Subset)
Layer2 = View1.CreateLayer(Task.OUTPUT_RASTER)This tasks wraps the ENVI Classic rgb_itrans_doit and converts an image from hue/lightness/saturation (HLS) to red/green/blue (RGB). The below example creates an HLS raster and then performs the inverse transform to RGB.
; Start the application
e = ENVI()
; Load our extra tasks
xtTasksInit
; Open an input file
File = Filepath('qb_boulder_msi', Subdir=['data'], $
Root_Dir=e.Root_Dir)
Raster = e.OpenRaster(File)
; Process a spectral subset (three bands)
Subset = ENVISubsetRaster(Raster, BANDS = [0,1,2])
; Stretch our data so that we are in 0-255 RGB space
stretched = ENVILinearPercentStretchRaster(subset)
; Generate an HLS raster
forwardTask = ENVITask('XTRGBtoHLSRaster')
forwardTask.INPUT_RASTER = stretched
forwardTask.Execute
; Convert back to RGB
inverseTask = ENVITask('XTHLStoRGBRaster')
inverseTask.INPUT_RASTER = forwardTask.OUTPUT_RASTER
inverseTask.Execute
; Get the collection of data objects currently available in the Data Manager
DataColl = e.Data
; Add the output to the Data Manager
DataColl.Add, forwardTask.OUTPUT_RASTER
DataColl.Add, inverseTask.OUTPUT_RASTER
; Display the result
View1 = e.GetView()
Layer1 = View1.CreateLayer(Subset)
Layer2 = View1.CreateLayer(forwardTask.OUTPUT_RASTER)
Layer3 = View1.CreateLayer(inverseTask.OUTPUT_RASTER, BANDS = [2,1,0])This tasks wraps the ENVI Classic rgb_itrans_doit and converts an image from hue/saturation/value (HSV) to red/green/blue (RGB). The below example creates an HSV raster and then performs the inverse transform to RGB.
; Start the application
e = ENVI()
; Load our extra tasks
xtTasksInit
; Open an input file
File = Filepath('qb_boulder_msi', Subdir=['data'], $
Root_Dir=e.Root_Dir)
Raster = e.OpenRaster(File)
; Process a spectral subset (three bands)
Subset = ENVISubsetRaster(Raster, BANDS = [0,1,2])
; Stretch our data so that we are in 0-255 RGB space
stretched = ENVILinearPercentStretchRaster(subset)
; Generate an HLS raster
forwardTask = ENVITask('XTRGBtoHSVRaster')
forwardTask.INPUT_RASTER = stretched
forwardTask.Execute
; Convert back to RGB
inverseTask = ENVITask('XTHSVtoRGBRaster')
inverseTask.INPUT_RASTER = forwardTask.OUTPUT_RASTER
inverseTask.Execute
; Get the collection of data objects currently available in the Data Manager
DataColl = e.Data
; Add the output to the Data Manager
DataColl.Add, forwardTask.OUTPUT_RASTER
DataColl.Add, inverseTask.OUTPUT_RASTER
; Display the result
View1 = e.GetView()
Layer1 = View1.CreateLayer(Subset)
Layer2 = View1.CreateLayer(forwardTask.OUTPUT_RASTER)
Layer3 = View1.CreateLayer(inverseTask.OUTPUT_RASTER, BANDS = [2,1,0])