ISIS Application Documentation
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Apply a spectral division filter
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Name | Description |
---|---|
FROM | Input file |
TO | Filtered output cube |
Name | Description |
---|---|
BANDS | Number of bands in boxcar |
Name | Description |
---|---|
LOW | Minimum valid DN |
HIGH | Maximum valid DN |
Input cube to filter
Type | cube |
---|---|
File Mode | input |
Filter | *.cub |
The resultant filtered cube
Type | cube |
---|---|
File Mode | output |
Pixel Type | real |
Filter | *.cub |
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 |
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 |
|
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 |
|
Example of usage of the spectral division filter.
Example GUI Screenshot of the GUI with parameters set to perform the specdivision filter with a 15 band boxcar on the image CM_1514302573_1.ir.cub. |
Input image spectral graph before specdivfilter
Parameter Name:
FROM This is the spectral plot of the center point of the image, (32, 32), and shows all bands, 1- 256. No filter has been applied, and the graph clearly shows how the value of line 32 sample 32 differs from band to band. |
Output image spectral graph after being filtered
Parameter Name:
TO This is the image after the filter. First note the change in scale, everything has been amplified. Even in the apparent flat area small differences have been amplified. |
Example of usage of the spectral division filter.
Example GUI Screenshot of the GUI with parameters set to perform the spechighpass filter with a 61 band boxcar on the image CM_1514302573_1.ir.cub. |
Input image spectral graph before spectral division 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 or amplification has been applied. |
Output image spectral graph after being filtered
Parameter Name:
TO This is the image after the filter. The amplification is clear immediately from the change in scale necessary to show the new values. All differences have been amplified, but smaller differences have increased more significantly than large differences. |
Stacy Alley | 2008-09-02 | Original version |
Mackenzie Boyd | 2009-06-05 | Modified documentation, added error checking for the number of bands, and added examples |