Developer Reference

  • 2021
  • 03/26/2021
  • Public Content

Motion Representation

Motion Image History”
(a) shows capturing a foreground silhouette of the moving object or person. As the person or object moves, copying the most recent foreground silhouette as the highest values in the motion history image creates a “layered history” of the resulting motion. Typically, this “highest value” is just a floating-point timestamp of time since the code has been running in milliseconds. Figure
Motion Image History”
(b) shows the result that may be called the
Motion History Image (MHI)
. The MHI in Figure
Motion Image History”
represents how the motion took place. A pixel level or a time delta threshold, as appropriate, is set such that pixel values in the MHI that fall below that threshold are set to zero.
Motion Image History
The most recent motion has the highest value, earlier motions have decreasing values subject to a threshold below which the value is set to zero.

Product and Performance Information


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