ISIS Application Documentation
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Extracts a sub-area from a cube
Overview | Parameters | Example 1 |
DescriptionThis program extracts a sub-area from a cube based on user defined parameter values. The extracted area can also be sub-sampled by specifying a line and sample increment. A sub-area selected for extraction must be contiguous. That is, the program will not allow non-continuous cropping such as lines 1-5, 10-30, and 80-100. However, the contiguous area can be sub-sampled by specifying how many pixels to increment or skip. For example, to select every third line (1, 4, 7, 10 ...) to be written to the output cube, use a line increment (LINC) of three. The parameter PROPSPICE applies to Level1 images. The SPICE information must have been propagated to the cropped output cube to obtain any camera geometry or photometric information. The default setting for PROPSPICE is "TRUE." When the default setting is used, all the keywords in the labels of the input file are transferred to the output file. In addition, the keywords that describe the area that was extracted out of the input cube are also added to the AlphaCube group in the labels. For a Level1 image, the keywords contained within the AlphaCube group in the labels describe the original file size and the area that was extracted. The AlphaCube and SPICE kernels information are very important to compute accurate geometric and photometric information using the cropped Level1 cube.
For a Level2 image or a mosaic, the Mapping group keywords in the labels are updated or removed depending on the settings used to crop the input image. Once an image has been cropped, the keywords MinimumLatitude, MaximumLatitude, MinimumLongitude, and MaximumLongitude are recomputed and the values updated in the labels for rectangular projections with straight line meridians and parallels. The keywords are removed from the labels for projections with curved meridians and parallels. Use the map2map application if the keywords MinimumLatitude, MaximumLatitude, MinimumLongitude, and MaximumLongitude must be retained in the labels. If the parameters LINC and SINC are not 1 and the values are equal, then the map Scale and PixelResolution are recomputed and the values updated in the labels. Otherwise, Scale and PixelResolution keywords and values are removed from the labels. The UpperLeftCornerX and UpperLeftCornerY are recomputed based on the settings used to crop the input image and updated in the labels for all projections as shown in the example below.
WARNING:
CategoriesRelated Applications to Previous Versions of ISISThis program replaces the following applications existing in previous versions of ISIS:
Related Objects and DocumentsApplicationsHistory
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U.S. Department of the Interior | U.S. Geological Survey ISIS | Privacy & Disclaimers | Astrogeology Research Program To contact us, please post comments and questions on the USGS Astrogeology Discussion Board To report a bug, or suggest a feature go to: ISIS Github File Modified: 10/05/2024 02:42:20 |
Parameter GroupsFiles
Sample Extraction
Line Extraction
MISC
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U.S. Department of the Interior | U.S. Geological Survey ISIS | Privacy & Disclaimers | Astrogeology Research Program To contact us, please post comments and questions on the USGS Astrogeology Discussion Board To report a bug, or suggest a feature go to: ISIS Github File Modified: 10/05/2024 02:42:20 |
This is the input cube that will be cropped.
Type | cube |
---|---|
File Mode | input |
Filter | *.cub |
The smaller output cube containing the results of crop.
Type | cube |
---|---|
File Mode | output |
Filter | *.cub |
This is the starting sample of the area to extract. It must be inside the cube area.
Type | integer |
---|---|
Default | 1 |
Minimum | 1 (inclusive) |
This defines how many samples to extract from the input cube, if SINC is 1. Otherwise, the number of samples actually extracted from the input cube is NSAMPLES/SINC.
Type | integer |
---|---|
Internal Default | All samples |
Minimum | 1 (inclusive) |
This specifies the sample increment to use when extracting from the input cube. This effectively skips samples when the value is greater than 1. For example, if SINC=2 and SAMPLE=1 the output cube would contain samples 1, 3, 5, 7, and so on. Note that this reduces the size of the output cube as specified by NSAMPLES. That is, if NSAMPLES=200 and SINC=2, the output cube will have 100 samples.
Type | integer |
---|---|
Default | 1 |
Minimum | 1 (inclusive) |
This is the starting line of the area to extract. It must be inside the cube.
Type | integer |
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Default | 1 |
Minimum | 1 (inclusive) |
This defines how many lines will be extracted from the input cube, if LINC is 1. Otherwise, the number of lines actually extracted from the input cube is NLINES/LINC.
Type | integer |
---|---|
Internal Default | All lines |
Minimum | 1 (inclusive) |
This specifies the line increment to use when extracting from the input cube. This effectively skips lines when the value is greater than 1. For example if LINC=2 and LINE=5 the output cube would contain lines 5, 7, 9, 11, and so on. Note that this reduces the size of the output cube as specified by NLINES. That is, if NLINES=200 and LINC=2, the output cube will have 100 lines.
Type | integer |
---|---|
Default | 1 |
Minimum | 1 (inclusive) |
This specifies whether or not to propagate the SPICE Kernels group to the output file for a Level 1 image. If this parameter is set to "False," then there will be no camera model available to compute geometric and photometric information using the cropped cube.
Type | boolean |
---|---|
Default | true |
U.S. Department of the Interior | U.S. Geological Survey ISIS | Privacy & Disclaimers | Astrogeology Research Program To contact us, please post comments and questions on the USGS Astrogeology Discussion Board To report a bug, or suggest a feature go to: ISIS Github File Modified: 10/05/2024 02:42:20 |