circle
Trims data outside of a circle
This program will trim (set to NULL) all pixels in an input cube
which fall outside of a user defined circle. That is, given a
sample/line coordinate and a radius, all pixels whose distance away
from the input sample/line is further than the radius will be set to NULL.
This program is useful for trimming global cubes collected by framing
cameras. A global cube is one in which the limb of the planet/target body
is visible and therefore the camera has taken a picture of space as well as
the planet. Using this program you can ensure the space pixels are NULL.
This can be done by determining the sub-spacecraft point in sample/line
coordinates and the radius of the body. Note that the sample/line position
does not have to be within the image in question.
Categories
History
| Kay Edwards | 1986-02-03 | Original version |
| Jeff Anderson | 2002-06-19 | Ported to Isis 3.0 |
| 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 |
| Steven Lambright | 2008-05-12 | Removed references to CubeInfo |
| Kimberly Oyama | 2012-05-25 | Added the functionality of circle2; the user can define a circle by three points on its edge instead of the center and radius. Fixes #518 |
Parameters
Files
Use this parameter to select the filename. All bands within the file
will be trimmed.
| Type | cube |
|---|---|
| File Mode | input |
| Filter | *.cub |
This file will contain the results of the circle trim.
| Type | cube |
|---|---|
| File Mode | output |
Define Circle By:
| Type | string | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Default | CENTERRAD | |||||||||
| Option List: |
|
Enter Center and Radius
This defines the sample coordinate at the center of the circle.
It can be negative or greater than the number of samples in the
cube.
| Type | double |
|---|---|
| Internal Default | Middle sample |
This defines the line coordinate at the center of the circle.
It can be negative or greater than the number of lines in the
cube.
| Type | double |
|---|---|
| Internal Default | Middle line |
This defines the radius of the circle. Pixels outside the radius
of the circle centered at (SAMPLE,LINE) will be trimmed. The default
value is the lesser of half the samples or half the lines.
| Type | double |
|---|---|
| Internal Default | Half the image size |
| Minimum | 1.0 (inclusive) |
Enter 3 Points on Edge
This defines the sample coordinate of a point on the circle.
| Type | double |
|---|---|
| Default | 0 |
This defines the line coordinate of a point on the circle.
| Type | double |
|---|---|
| Default | 0 |
This defines the sample coordinate of a point on the circle.
| Type | double |
|---|---|
| Default | 0 |
This defines the line coordinate of a point on the circle.
| Type | double |
|---|---|
| Default | 0 |
This defines the sample coordinate of a point on the circle.
| Type | double |
|---|---|
| Default | 0 |
This defines the line coordinate of a point on the circle.
| Type | double |
|---|---|
| Default | 0 |
Example 1
Taking all defaults
This example shows the result of taking all the default
parameters on the application circle.
line and samp defaulted to the center of the image, and
radius defaulted to the minimum of nl/2.0 and ns/2.0
Command Line
line and sample default to the center of the image, radius defaults to the
lesser one half of the number of lines or the number of samples
circle from=circle_in to=circle1_out
GUI Screenshot
Example GUI
Circle GUIScreenshot of GUI with parameters filled in to perform the default circle operation
Input Image
Input image for circle
Input image
Parameter Name:
FROM
This is the input image for the default example of circle.
Output Image
Output image for circle
Output image showing results of the circle application defaults
Parameter Name:
TO
This is the output image for circle. Notice the NULL values in the corners of this image.
Example 2
Small centered circle
This example shows the result of setting a smaller radius than the minimum of
ns/2.0 and nl/2.0. The center of the circle defaults to the center of the image
Command Line
line and sample default to the center of the input image, with a radius of 150
pixels
circle from=circle_in to=circle_out rad=150
GUI Screenshot
Example GUI
Circle GUIScreenshot of GUI with parameters filled in to perform a circle operation with a radius of 150
Input Image
Input image for circle
Input Image
Parameter Name:
FROM
Input image
Output Image
Circle radius smaller than image
Output image showing results of the circle application with a user defined radius
Parameter Name:
TO
Output image for circle radius = 150 on a 500 by 500 image
Example 3
Off centered
This example shows the result of circle when the radius center is placed
at the center of the upper right quadrant of the image. The radius is large
enough to include data not in the immage.
Command Line
the center of the circle is line 125 and sample 375, with a radius of 200
circle from=circle_in to=circle2_out line=125 samp=375 rad=200
GUI Screenshot
Example GUI
Circle GUIScreenshot of GUI with parameters filled in to perform a circle operation with a radius of 200 and centered on line/sample 125/375
Input Image
Input image for circle
Input image
Parameter Name:
FROM
This is the input image for the default example of circle.
Output Image
Output image off centered example of circle
Output image showing results of the circle application with all parameters defined
Parameter Name:
TO
This is the output image for circle. Notice the NULL values of this image.