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A motion detection camera system which may be used as a security camera includes an active pixel imaging system operable in a video and differential mode connected to a mode activation circuit that controls the imaging system mode. In the video mode, the imaging system generates an output signal con

A motion detection camera system which may be used as a security camera includes an active pixel imaging system operable in a video and differential mode connected to a mode activation circuit that controls the imaging system mode. In the video mode, the imaging system generates an output signal containing information of a viewed area on a frame by frame manner. In the differential mode, the imaging system generates a differential output signal containing information consisting of the differences in the viewed area between adjacent detected frames. Normally, the imaging system camera is operated in the differential mode. If no motion occurs in the viewed area, the corresponding differential output signal representing the interframe differences will have a constant signal level. Upon detecting that the differential output signal deviates by greater than a threshold level indicating motion in the viewed area, the mode activation circuit causes the imaging system to operate in its video mode. The corresponding generated video output signal of the imaging system is then provided to monitoring equipment, such as a video cassette recorder for recording of the motion in the viewed area.

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A motion detection camera system comprising: an active pixel imaging system having an output and a mode select input, the imaging system being operable in a differential or video mode based on the signal at the mode select input, wherein the imaging system generates a video signal containing informa

A motion detection camera system comprising: an active pixel imaging system having an output and a mode select input, the imaging system being operable in a differential or video mode based on the signal at the mode select input, wherein the imaging system generates a video signal containing information for each detected image frame of a viewed area when in the video mode and a differential signal containing information of interframe differences when in the differential mode, the imaging system further comprising: (i) a plurality of active pixel sensors arranged in an array of rows and columns, each active pixel sensor being operable to generate a voltage at a diffusion node corresponding to detected light intensity by the sensor, each active pixel sensor being further operable to buffer the voltage potential present on the diffusion node from other signals generated external to the sensor; (ii) means for sequentially activating sensors in different portions of the array for a period of time to achieve a desired detected frame interval; (iii) a plurality of output circuits, each output circuit being connected to the respective sensors in a corresponding portion of the array, each output circuit being operable to store first and second voltage signals received from the connected sensors and to selectively provide a sensor output signal to the imaging system output; and (iv) a timing controller connected to the activating means and each differential output circuit, wherein the timing controller is operable to cause each sensor row to be sequentially activated, and when in a differential mode, to cause the activated sensors to provide a voltage signal corresponding to a previous detected frame to the output circuits and then to provide a voltage signal corresponding to a present detected frame to the output circuits, and when in a video mode, to cause the activated sensors to provide a voltage signal corresponding to a reference voltage to the output circuits and then to provide a voltage signal corresponding to a present detected frame to the output circuits, and wherein the timing controller is further operable to cause the output circuits to sequentially provide the output signals to a common output line to generate either of the imaging system output signals; a switch having an input, first and second outputs and a control input, the input being connected to the imaging system output, the first output being operable to provide a video output signal to a monitoring device; a threshold detector having an input and an output, the input being connected to the second switch output; and a mode selector having an input and an output, the input being connected to the detector output, the output being connected to the switch control input and the imaging system mode select input.