Point Cloud Scale Transform

Functional Description

This operator performs a uniform scale (zoom) transformation on the input point cloud data. It multiplies the X, Y, and Z coordinates of each point in the point cloud by a user-specified scaling factor, thus achieving magnification or reduction of the point cloud.

Usage Scenarios

  • Unit Conversion: When the units of the point cloud data are inconsistent with the units required by subsequent processing flows (e.g., converting from meters to millimeters, or vice versa), this operator can be used for conversion. For example, magnifying a point cloud in meters by 1000 times to obtain a point cloud in millimeters.

  • Thermal Drift Correction: In some scenarios where thermal drift occurs, the point cloud can be corrected using the dimensions obtained from calibration board detection or sphere fitting result generation pose nodes.

Inputs and Outputs

Input Items

Camera coordinate system point cloud: Point cloud data that needs to undergo scale transformation.

Proportion: The scaling factor used to scale the point cloud. If this port is connected to data, the value from this port is prioritized, which can be obtained from the dimensions of the "Calibration Board Detection" or "Generate Pose from Sphere Fitting Result" nodes; otherwise, the "Proportion" value in the parameter settings below is used.

Output Items

Camera coordinate system point cloud: Point cloud data after scale transformation.

Parameter Description

This operator has two versions:

  • Point Cloud Scale Transform : Processes point clouds without normal information.

  • Point Cloud Scale Transform(with Normals) : Processes point clouds with normal information.

Both have identical core functionality and parameters, only differing in the type of point cloud data they process.

  • Proportion Source: The operator’s priority for obtaining the scaling factor is: Input Port > Runtime Parameter. If neither provides a valid value, the operator will report an error.

  • Uniform Scaling: This operator performs uniform scaling, meaning the same scaling factor is used for the X, Y, and Z directions.

Proportion

Parameter Description

"Specifies the scaling factor for point cloud scaling. Each coordinate value (X, Y, Z) of the point cloud will be multiplied by this value."

Tuning Description

  • ratio > 1: Magnifies the point cloud. For example, setting it to 1000 can convert units from meters to millimeters.

  • ratio = 1: The point cloud remains unchanged.

  • 0 < ratio < 1: Reduces the point cloud. For example, setting it to 0.001 can convert units from millimeters to meters.

  • ratio = 0: Transforms all points to the origin (0, 0, 0), which usually has no practical significance.

  • Priority: If the input port "Proportion (ratio)" is connected to data, the operator will prioritize using the value from the input port and ignore the value set in this parameter. If the input port is not connected, a valid ratio value must be set in this parameter, otherwise the operator will report an error.

Parameter Range

[0, 10], Default is empty, please set according to actual needs.

Enable node

Parameter Description

Controls whether this operator performs the scale transformation operation.

Tuning Description

The switch is enabled by default, and the operator performs the scaling function normally; if this switch is turned off, the operator performs no operations and directly passes the input point cloud to the output port.