1. A image sensor comprising: a camera configured to capture images of an area corresponding to a location of the image sensor; a passive infrared motion sensor configured to sense motion in the location of the image sensor; an analog filter that is configured to filter noise from the output of the passive infrared motion sensor and generate a trigger based on the output of the passive infrared motion sensor being indicative of motion other than noise; an analog-to-digital convertor configured to digitize the output of the passive infrared motion sensor; a digital filter that is configured to wake up from a sleep mode based on the analog filter generating the trigger, the digital filter processing the digitized output of the passive infrared motion sensor to determine whether the motion other than noise detected by the analog filter relates to real motion; and at least one processor configured to control the camera to capture an image based on the digital filter determining that the motion other than noise detected by the analog filter relates to real motion.