ISIS Application Documentation
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Apply a spatial high pass filter to a cube
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Name | Description |
---|---|
FROM | Input file |
TO | Output highpass cube |
Name | Description |
---|---|
SAMPLES | Number of samples in boxcar |
LINES | Number of lines in boxcar |
MINOPT | Sets minimum to be either a count or a percentage |
MINIMUM | Minimum boxcar pixel count |
Name | Description |
---|---|
LOW | Valid minimum pixel |
HIGH | Valid maximum pixel |
PROPAGATE | Propagate special pixels |
ADDBACK | Percentage of input pixel to add back to the filter |
Input cube to filter
Type | cube |
---|---|
File Mode | input |
Filter | *.cub |
The resultant filtered cube
Type | cube |
---|---|
File Mode | output |
Pixel Type | real |
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 |
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 for filtering to occur. For example, 3x5 boxcar has 15 pixels inside. If MINIMUM=10 then the filter will occur if there are 10 or greater 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) |
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 statistics.
Type | double |
---|---|
Internal Default | Use all pixels |
Less Than |
|
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 statistics.
Type | double |
---|---|
Internal Default | Use all pixels |
Greater Than |
|
This option is used to define how special pixels are handled. If the center pixel of the boxcar is a special pixel it will be propagated or set to NULL depending on the value of this parameter.
Type | boolean |
---|---|
Default | TRUE |
This option is used to specify how much of the input pixel is added to the filter result. A value of 100 implies the entire input pixel will be added back to the filter which is equivalent to the sharpen program. Recall that highpass filters suppress albedo and therefore you are essentially selecting a percentage of albedo to addback.
Type | double |
---|---|
Default | 0.0 |
Minimum | 0.0 (inclusive) |
Maximum | 100.0 (inclusive) |
7 by 7
Example GUI Screenshot of GUI with parameters filled in to perform the 7x7 filter - with low, high, min default - highpass operation |
Input image for highpass
Parameter Name:
FROM This is the input image for the 7x7 example of highpass. |
Output image 7x7 example of highpass
Parameter Name:
TO This is the output image for highpass. Notice the smoothing of abedo typical of high pass filtering, which leaves terrain more visible. This smaller filter leaves smaller features visible. |
21 by 21
Example GUI Screenshot of GUI with parameters filled in to perform the 21x21 filter - with low, high, min default - highpass operation |
Input image for highpass
Parameter Name:
FROM This is the input image for the 21x21 example of highpass. |
Output image 21x21 example of highpass
Parameter Name:
TO This is the output image for highpass. This larger filter leaves larger features visible. |
Eric Eliason | 1988-05-20 | Original version |
Jeff Anderson | 2002-07-30 | Ported to Isis 3.0 |
K Teal Thompson | 2002-11-19 | Add examples. |
K Teal Thompson | 2002-12-09 | Make images smaller |
K Teal Thompson | 2003-03-19 | Add move images to /image and /thumb directory. |
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 |
Stuart Sides | 2004-02-17 | Added addback parameter |