trimfilter
Apply a trim filter to a cube
This program convolves an NxM boxcar through a cube and trims (or NULLs)
pixels. A pixel at the center of the boxcar is trimmed in the output cube
if the number of valid pixels inside the boxcar is less than a user
specified minimum. Valid pixels are defined as those which are 1) not
special pixels and 2) inside the range of the LOW and HIGH parameters.
This is a very powerful trimming tool although much
thought must be put into the parameters in order to obtain the optimal
trimming results.
Categories
Related Applications to Previous Versions of ISIS
This program replaces the following application existing in previous versions of ISIS:- boxfilter
Related Objects and Documents
Applications
History
| Eric Eliason | 1988-05-20 | Original version |
| Jeff Anderson | 2002-08-01 | Ported to Isis 3.0 |
| K Teal Thompson | 2002-12-03 | Add example |
| K Teal Thompson | 2003-03-28 | Make images smaller. |
| Stuart Sides | 2003-04-04 | Fixed problem with isiscvs not checking in the thumb and image directories. |
| Kim Sides | 2003-05-13 | Added application test |
| Stuart Sides | 2003-05-16 | Modified schema location from astogeology... to isis.astrogeology..." |
| Stuart Sides | 2003-07-29 | Modified filename parameters to be cube parameters where necessary |
| Brendan George | 2006-03-20 | Added Minopt parameter |
Parameters
Files
Input cube to filter
| Type | cube |
|---|---|
| File Mode | input |
| Filter | *.cub |
The resultant trimmed cube
| Type | cube |
|---|---|
| File Mode | output |
Boxcar Size
This is the total number of samples in the boxcar.
It must be odd and can not exceed twice the number of samples
in the cube. In general, the size of the boxcar does not
cause the program to operate significantly slower.
| Type | integer |
|---|---|
| Minimum | 1 (inclusive) |
| Odd | This value must be an odd number |
This is the total number of lines in the boxcar.
It must be odd and can not exceed twice the number of lines
in the cube. In general, the size of the boxcar does not
cause the program to operate significantly
slower.
| Type | integer |
|---|---|
| Minimum | 1 (inclusive) |
| Odd | This value must be an odd number |
Boxcar Restrictions
Valid minimum pixel value that will be used in boxcar computation. If
a pixel value is less than LOW then it will not be used when
computing boxcar counts.
| Type | double |
|---|---|
| Internal Default | Use all pixels |
| Less Than | HIGH |
Valid maximum pixel value that will be used in boxcar computation. If
a pixel value is greater than HIGH then it will not be used when
computing boxcar counts.
| Type | double |
|---|---|
| Internal Default | Use all pixels |
| Greater Than | LOW |
This parameter determines whether the minimum
parameter is to be interpreted as a count of pixels, or a
percentage of all pixels in the boxcar.
| Type | string | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Default | COUNT | |||||||||
| Option List: |
|
This is the minimum number of valid pixels which must occur inside the
NxM boxcar in order to preserve the output pixel.
For example, a 3x5 boxcar has 15 pixels
inside. If MINIMUM=10 then the trimming will occur if there are 9 or
less valid pixels. A valid pixel is one that is not special (NULL, LIS,
etc) and is in the range defined by LOW to HIGH.
| Type | double |
|---|---|
| Default | 1 |
| Minimum | 1 (inclusive) |
Example 1
run a trim filter
This example shows a trimfilter operation.
Command Line
trimfilter a Lunar Orbiter image.
trimfilter f=../IN/lo880.crp.cub t=OUT/trmfltr s=1 li=301 high=241 min=95
GUI Screenshot
Example Gui
trimfilter GuiScreenshot of GUI with parameters filled in to perform a trimfilter operation on the input image.
Input Image
Input image for trimfilter
Input image
Parameter Name:
FROM
This is the input image for the trimfilter example.
Output Image
Output image for trimfilter
Output image showing results of the trimfilter application.
Parameter Name:
TO
This is the output image that results.