Reference
Components
Motion Detect
Description
Motion Detect is a video processing component that locates areas of movement in an image.
Each new image is compared with the frame before and if any pixel differs by more than the Delta input value then this is registered as
movement and stored in a binary image.
These binary images are stored over a period of time defined by the Duration input (Dur). The images are then faded out with the oldest
image being almost transparent and the most recent being fully opaque. These images are overlayed to produce a movement gradient called
the Motion History Image (MHI).
The algorithm looks at the MHI and for each pixel it examines the neighbouring pixels to determine the difference in intensity gradient. If the
gradient falls between the MinT and MaxT values then it registers that movement has occurred.
MinT is the minimum MHI duration and MaxT is the maximum MHI duration. Because the gradient exactly corresponds to the duration inside
the MHI these values are specified as times in seconds. So differences in intensity between neighbouring pixels are equivalent to differences
in time between neighbouring pixels.
Connectors
Inputs Type Outputs Type
The source image you want
to process
Bitmap Motion history image
Bitmap
Threshold for detecting
image transitions. Default is
30
Int Whether any
movement was
detected
Boolean
Duration of motion image
history (seconds). Default is
1sec.
Float X coordinates of
centre detected
movements (pixels)
Float Array
Minimum MHI duration
(seconds). Default is 0.05
Float Y coordinates of
centre of detected
movements (pixels)
Float Array
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