Sensoray 2251 Rev.A - Manual (Page 44)

Figure 6
The produced motion map when motion occurs is shown in Figure 6. The black rectangle
shows macroblocks outside the area of interest. As example earlier, these may be ignored. The
number of hits 37 is the number of times a motion event occurred in region 1. It is not a count
of the macroblocks in the region.
Advanced: Note that no macroblocks are shown below the region in the y direction. When a
motion map is created, it scans from left to right starting at the top and going to the bottom.
Any macroblock motion along the scan line is included in the motion map. So stray motion
events(which may be ignored) occur beside the region, but not above or below the region.
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