I want to install a security system inside the fence against the thiefs. I want it to trigger the alarm on presence of any human in the area. For using motion sensor cats keep wandering inside the fence which will also trigger motion sensor. Is there any software which will detect human in area and eliminate cats which can be coupled with ir camera (for night).i saw some builds of neural networks which need training. But i want something which dont need training and will differentiate any big thing like above 4 feet from cats even if it is unable detect it as a human. If not software tell some good AI which i can use and also sensors.(i will use it with raspberry pi). Fine with any language. If not for both light n night vision ok if it works with only night vision(infrared). Any help will be appreciated. Thanks.