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Table of Contents
Signal Commands Overview
Signal functions are used to manipulate signals within Visual3D expressions. These can be used in the Evaluate_Expression pipeline command or anywhere in Visual3D where expressions are used.
Signal Math
These functions can be combined by users to create custom mathematical expressions.
| Function | Description |
|---|---|
| Add_Constant_To_Signals | Adds a constant to the specified components of a signal(s). |
| Add_Random_Noise_To_Signals | Adds random noise to the specified signal(s). |
| Add_Signals | Add the specified signals. Signals must be at the same sampling rate. If your signals are a different rate, you can use the Evaluate_Expression command, which determines an appropriate rate automatically. |
| Divide_Signals | This command will divide signals with the first signal being the numerator. |
| Divide_Signal_By_Constant | This command will divide a specified components of a signal(s) by a constant. |
| First_Derivative | Compute the first derivative at each point of a signal. This command is useful for calculating the velocity of targets, landmarks, etc. |
| Second_Derivative | Compute the second derivative at each point of a signal. This command is useful for calculating the acceleration of targets, landmarks, etc. |
| Multiply_Signals | Multiply the components of the specified signals. |
| Multiply_Signals_By_Constant | Multiply signals by a constant value. |
| Indefinite_Integral | Compute an indefinite integral from the start event to the stop event. |
| Signal_Magnitude | Calculate the magnitude of a signal according to: Magnitude=Sqrt( x^2+y^2+z^2 ) |
| Subtract_Constant_From_Signals | Subtracts a constant from the specified components of a signal(s). |
| Subtract_Signals | Subtract the components of the specified signals. |
| Square_Root | Compute the square root of a signal or metric. This command can be used to compute the vector magnitude of a signal. |
| Compute_Planar_Angle | This command computes a planar angle between three or four points. |
| Compute_Volume_Of_Chest_Wall | |
| Compute_Volume_Of_A_Convex_Hull |
Signal/Data Management
Create_Target
Global_Normalized_Signal_Mean
Find_Representative_Signal
Merge_Data
This command merges data from more than one data name into a single one either by appending one signal to the end of another signal or by treating each original signal as a component of the new signal.
Copy_Folder
Makes a copy of an existing folder. If the new folder already exists, select whether these signals should be overwritten (replaced).
Rename_Folder
This command renames the specified folder.
Delete_Folder
Deletes the specified folder. Note that ORIGINAL folders can not be deleted.
Remove_Signals
Rename_Signals
Remove_Unlabeled_Points
Vicon Nexus exports unlabeled trajectories, and identifies them by placing an asterisk (*) at the beginning of the filename
Remove_Polygon_Signals
Remove processed signals generated by Polygon and stored as POINT data in the c3d file.
Signal Filter
Average_Filter
FFT_Filter
GCVSPL
Lowpass Filter
Highpass Filter
Onepass_Filter
Median_Filter
Moving_RMS
Teager_Kaiser_Energy
Teager-Kaiser Energy Operator
Using the matlab fda tool for designing a notch filter
Shift_Frames
Signal Process
Interpolate
Replace
Set_Data_To_New_Values
Rectify
First_Derivative
Second_Derivative
Transform_Data_Coordinate_System
Distance_Along_Path
Distance_Parallel_To_Path
Distance_Perpendicular_To_Path
Compute_UD_Power
Cross_Correlation
Compute_IK_Residuals
Examples
Example_-_Intersection_of_two_lines
Compute the intersection of two lines
Example_-_Intersection_of_a_line_and_a_plane
Compute the intersection of a line with a plane
Example_-_Computing_the_head_fixation_point
The head fixation point is the intersection between the anterior direction of the head at one frame of time and an another frame of time. This examples makes use of the example for computing the Intersection of 2 Lines found above.