HighPassKernel Task
This task returns a high pass kernel of a specified size for use with convolution filtering. ENVI’s high pass kernel consists of a high central value, surrounded by negative weights. The default kernel size is 3x3.
Example
; Start the application
e = ENVI()
; Get the task from the catalog of ENVITasks
Task = ENVITask('HighPassKernel')
; Define outputs
Task.KERNEL_SIZE = [3,5]
; Run the task
Task.Execute
; Print the resulting 3x5 kernel
print, Task.OUTPUT_KERNEL
IDL prints:
-1.00000 -1.00000 -1.00000
-1.00000 -1.00000 -1.00000
-1.00000 14.0000 -1.00000
-1.00000 -1.00000 -1.00000
-1.00000 -1.00000 -1.00000
Syntax
Result = ENVITask('LowPassKernel')
Input properties (Set, Get): KERNEL_SIZE
Output properties (Get only): OUTPUT_KERNEL
Properties marked as "Set" are those that you can set to specific values. You can also retrieve their current values any time. Properties marked as "Get" are those whose values you can retrieve but not set.
Methods
This task inherits the following methods from ENVITask:
Properties
KERNEL_SIZE (optional)
Specify a two-element array [n,m] as the kernel size, where n is the number of columns and m is the number of rows. The default kernel size is [3,3].
OUTPUT_KERNEL
This is the low pass kernel output.
Version History
|
ENVI 5.3 |
Introduced |
API Version
4.2
See Also
ENVITask, DirectionalFilter Task, DirectionalKernel Task, HighPassFilter Task, LaplacianFilter Task, LaplacianKernel Task, LowPassFilter Task, LowPassKernel Task, MedianFilter Task, RasterConvolution Task, SobelFilter Task, RobertsFilter Task