For detecting the motion in a local space (region of a room) ; A continuous wave low power IR laser diode running at the wall (embedded or etc) and a LDR or photodiode (with the same spectral response) aligned at the reaching point of the LD. If an object passes between then the detector will know it. Very easy and cheap to implement. On the other hand; -a netbook with a webcam -linux -python is enough to determine the motion with high precision and details. You can even determine who are in the room if you construct a small database. On Fri, Mar 15, 2013 at 12:32 PM, Yigit Turgut wrote: > You can detect if there is a motion in the room but without image > processing you will not be able to determine the number of people in > the room. > > For detecting the motion in a local space (region of a room) ; > > A > > On Fri, Mar 15, 2013 at 12:21 PM, Art wrote: >> I want to detect human type people in a room or in a basement. >> >> The Ultimate design criteria is a low false positive alarm. After that, >> it's size, power usage and cost. >> >> Regards, >> >> Art >> >> On 03/15/2013 06:03 AM, Yigit Turgut wrote: >>> What is the scale of the motion you want to detect ? >>> >>> >> >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .