ISIS Application Documentation
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Apply a spectral high pass filter to a cube
Description
Categories
Groups
Examples
History
Description
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
Parameter Groups
Files
| Name | Description |
|---|---|
| FROM | Input file |
| TO | Output spechighpass cube |
Boxcar Size
| Name | Description |
|---|---|
| BANDS | Number of bands in boxcar |
Boxcar Settings
| Name | Description |
|---|---|
| LOW | Minimum valid DN |
| HIGH | Maximum valid DN |
Files: FROM
Description
Input cube to filter
| Type | cube |
|---|---|
| File Mode | input |
| Filter | *.cub |
Files: TO
Description
The resultant filtered cube
| Type | cube |
|---|---|
| File Mode | output |
| Pixel Type | real |
| Filter | *.cub |
Boxcar Size: BANDS
Description
This is the total number of bands in the boxcar. It must be odd and can not exceed twice the number of bands 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 Settings: LOW
Description
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 the average.
| Type | double |
|---|---|
| Internal Default | Use all pixels |
| Less Than |
|
Boxcar Settings: HIGH
Description
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 the average.
| Type | double |
|---|---|
| Internal Default | Use all pixels |
| Greater Than |
|
Examples
Example 1
Example of usage of the spectral highpass filter.
Description
Command Line
GUI Screenshot
spechighpass gui
|
Example GUI Screenshot of the GUI with parameters set to perform the spechighpass filter with a 15 band boxcar on the image CM_1514302573_1.ir.cub. |
Input Image
The image graph before the filter
|
Input image spectral graph before spechighpass filter
Parameter Name:
FROM This is the spectral plot of the center point of the image, (32, 32), and shows all bands, 1- 256. No averaging has been applied, this is clear partialy because of th extreme peaks visible in the first half. The peaks are related to values which differ significantly from the bands around them. |
Output Image
The image graph after the filter
|
Output image spectral graph after being filtered
Parameter Name:
TO This is the image after the filter. Although there are still sharp peaks, everything has been brought closer to zero. In the before image nearly all values are above zero, now the values are on either side of zero and are smaller. |
Example 2
Example of usage of the spectral highpass filter.
Description
Command Line
GUI Screenshot
spechighpass gui
|
Example GUI Screenshot of the GUI with parameters set to perform the spechighpass filter with a 63 band boxcar on the image CM_1516302573_1.ir.cub. |
Input Image
|
The image graph before the filter
|
Input image spectral graph before spechighpass filter
Parameter Name:
FROM This is the spectral graph of the input image at location (32, 32), notice the sharp peaks and all values greater than zero. |
Output Image
The image graph after the filter
|
Output image after being filtered
Parameter Name:
TO In this image the differences is that everything has been lowered except for the values already at zero. Some values which were positive are now negative as well. |
History
| Stacy Alley | 2008-09-02 | Original version |
| Mackenzie Boyd | 2009-06-04 | Added examples, modified documentation about boxcar size, added exception handling for too many bands |