Sensoray 2251 Rev.A - Manual (Page 47)

From pBuf[0], we have the motion detect events for the first 8 macroblocks. 0x7c= 01111100b
which represents the following:
Macroblock 1 : bit field = 0, so no motion.
Macroblocks 2-6 : bit field = 1, so motion detected
Macroblocks 7-8: no motion detected.
pBuf[1] = 0x00, so macroblocks 9-16 have no motion in them.
The motion map given in pBuf thus allows a user to create a custom motion detection
algorithm( The threshold will be the same for each macroblock) where they can generate
motion detection on an individual macroblock level (16x16 pixels).
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