Description
The ThinPoints process creates a new point cloud with a subset of the points from the input.
Inputs
A point cloud, variable resolution surface, or raster surface dataset.
Outputs
A point cloud in CSAR format.
Command Line Syntax
carisbatch --run ThinPoints --method <value> [options] <input> <output>
User Interface Command
Thin Points
Options
The following table describes the parameters available for this process.
Parameter |
| |||
|---|---|---|---|---|
Long | Short | Description | Can Repeat | Notes
|
Common Options | ||||
--method | m | The algorithm used to thin points from the input coverage. • RANDOM: Deletes a specified percentage of the points using random sampling. • MINIMUM_DISTANCE: Deletes points until no two points are within a specified distance. • APPLY_BIAS: Only the point with the minimum or maximum attribute value within its local neighborhood is kept. Note: All three methods use deterministic algorithms, meaning that running the process on the same dataset multiple times with the same settings will produce the same output each time. | FALSE | |
--include-band | b | A string specifying the name of a band to include in the output. The ALL keyword is used to include all other bands in the output. | TRUE | |
--comments | General comments to be added to the coverage metadata. The default value is an empty string. | FALSE | ||
Method = RANDOM Options | ||||
--percentage | The percentage of points removed. This number can be between 0 and 100, where 0 removes no points and 100 removes all points. | FALSE | ||
Method = MINIMUM_DISTANCE Options | ||||
--minimum-distance | d | The minimum distance between points in the output, in areas of the input with values. Note that output points could be up to 2x the minimum distance apart. | FALSE | |
--scale | s | A number specifying the scaling to apply to the radius (1:scale). The default scale value is 1, such that the value represents the minimum distance between features on the ground; the radius would then be a value like 5m. A scale of 1000 would mean that the value represents the minimum distance between features on a map at 1:1000 scale; the radius would then be a value like 10mm. | FALSE | |
Method = APPLY_BIAS Options | ||||
--input-band | i | A string specifying the name of the input band. The InputBand must contain numeric values. | FALSE | |
--bias | B | A string specifying how to select which values are chosen. • MIN: Points that have the minimum attribute value in their neighbourhood are kept. • MAX: Points that have the largest attribute value in their neighbourhood are kept. All values representing elevations are considered using the convention that up is positive. | FALSE | |
--minimum-distance | d | The minimum idistance between sounding features in the output, in areas of the input with values in the specified band. <Radius> - A number and unit specifying the minimum distance between sounding features. <MinValue> - A number and unit specifying the minimum value of the input band to apply this distance. <MaxValue> - A number and unit specifying the maxmum value of the input band to apply this distance. A least one radius must be specified. If CARIS:NONE is used as the <MinValue>, the minimum value of the data is used. Similarly, if CARIS:NONE is used as the <MaxValue>, the maximum value of the data is used. All values representing elevations are entered using the convention that up is positive. The unit must be specified, unless the input band is a unitless band. Support units: cable, ch, cm, fm, ft, in, inm, km, m, mi, mm, nm, usfm, usft, usmi, usnm, usyd, yd, deg and rad. | TRUE | |
--scale | s | A number specifying the scaling to apply to the radius (1:scale). The default scale value is 1, such that the radius represents the minimum distance between features on the ground; the radius would then be a value like 5m. A scale of 1000 would mean that the radius represents the minimum distance betwen features on a map at 1:1000 scale, the radius would then be a value like 10mm. | FALSE | |
--apply-designated | a | If set, designated soundings from the source of the input are included to the output. <MultipleDesignated> A string specifying how to handle multiple designated soundings closer than the minimum distance. • KEEP_ALL: Include all designated soundings to the output. • THIN: Thin designated soundings based on the bias. <BiasRelevance> A string specifying how to handle designated soundings and other points closer than the minimum distance. • APPLY_BIAS: Points that are selected based on the bias are included in the output regardless if a designated sounding is within the radius. The designated sounding is also included. • OVERRIDE_BIAS: Designated soundings thin all points within the radius, removing any points that otherwise would be selected based on the bias. | FALSE | |
To use this command refer to the following examples.
Example: Minimum Distance
Example | ||
|---|---|---|
Objective | You want to decrease the density of the data in a point cloud using the Minimum Distance thinning method. | |
Description | Command Line Syntax | |
The Minimum Distance thinning method is to be used. | --method MINIMUM_DISTANCE | |
All points closer than 5m will be removed from the output. | --minimum-distance 5m CARIS:NONE CARIS:NONE | |
The Depth and Shoal bands are to be included in the output. | --include-band Depth --include-band Shoal | |
The file to be thinned is named DenseCloud.csar and is in the BatchSample directory on the D: drive. | D:\BatchSample\DenseCloud.csar | |
The thinned point cloud will be called MinDistanceCloud.csar and will be saved to the same directory as the source. | D:\BatchSample\MinDistanceCloud.csar | |
Command Line |
| |
Outcome | A new, smaller point cloud is created in the specified location containing points no less than 15m apart. | |
Extra Notes | N/A | |
Example: Apply Bias
Example | ||
|---|---|---|
Objective | You want to decrease the file size of a variable resolution surface using the Apply Bias thinning method. | |
Description | Command Line Syntax | |
The Apply Bias thinning method is to be used. | --method APPLY_BIAS | |
The maximum values are to be kept during thinning. | --bias MAX | |
The Shoal band is to be included. | --include-band Shoal | |
Thinning is to be performed on the Elevation band. | --input-band Elevation | |
The following radius and interval values are to be used: • 0.5m, 1m, 3m • 1m, 3.01m, 5m • 1.5m, 5.01m, 7.5m • 3m, 7.51m, 10m • 5m, 10m, CARIS:NONE A radius of 15m will be used and the full range of elevations present in the band are to be analyzed. | --minimum-distance 0.5m 1m 3m --minimum-distance 1m 3.01m 5m --minimum-distance 1.5m 5.01m 7.5m --minimum-distance 3m 7.51m 10m --minimum-distance 5m 10m CARIS:NONE | |
All designated soundings are to be retained and any regular points within the radius of a designated sounding are to be thinned according to the bias rule. | --apply-designated KEEP_ALL APPLY_BIAS | |
The file to be thinned is named DenseVR.csar and is in the BatchSample directory on the D: drive. | D:\BatchSample\DenseVR.csar | |
The thinned point cloud will be called BiasThinVR.csar and will be saved to the same directory as the source. | D:\BatchSample\BiasThinVR.csar | |
Command Line |
| |
Outcome | A new point cloud is created in the location specified with less dense data. | |
Extra Notes | N/A | |