How does the process of transferring messages to a computer through a camera goes on?

Question

I want to know the steps behind the transfer of signals to a computer through a camera which will automatically perform all its functions.
I'm making a project in which a camera is fixed on one of the walls of a room, it'll detect the faces of people and automatically, the lights and fans will be turned on. Whereas, if there're no faces detected, then the electrical appliances will turn off on their own. This is useful in saving electricity. However, all this will be through the signals from the camera to a computer. But, I don't know how it works....so could anyone please help me regarding this?

Answer 1

Hi Shreya,



Your question is difficult to answer without knowing whether your are trying to create a conceptual model or a working prototype. What you are trying to do is already widely used in homes and businesses via motion sensors to determine the presence of people, animals or other activity.



See this article for an overview of the technology ~



http://en.wikipedia.org/wiki/Motion_sensor





Here is an article which explains the basics of Face Detection ~



http://en.wikipedia.org/wiki/Face_detection



The major drawback to the system you are trying to devise is that it requires a system that is too complex and costly. You can already buy affordable sensors that convert an analog signal being read by the detector into a "Digital" state (On/Off) that is converted to the "ON" state by a microchip (tiny computer) that switches the circuit ON, it then activates a timer to reset the switch to OFF after a certain interval. When the interval on the time expires the circuit signals the detector to check for motion, heat, etc. Then, if nothing is detected changes the switch to OFF., otherwise it resets the timer to check again after another time interval.



You can easily adapt a motion sensor, which is essentially a very primitive "digital camera" in most cases, to send its on/off signal to a computer to trigger a desired activity. Electronics supply stores like Radio Shack can usually provide you with materials to do this.



Hope that helps.

Answer 2

There are already several types of devices that are made to do what you want. They have Infrared and motion detection sensors.



While it sounds like a fun project, it is not feasible. Not all cameras feature a "face detection" or a "smile detection" option, and the ones that do need the shutter button depressed half way and then it will take a second or two for the camera to focus on that region. Plus, P&S cameras have a port to transfer file info, you would need a camera that can do tethering and remote operation (some DSLRs). The other downfall is that since the shutter button will be partially depressed, the camera will need to be on all the time and it will be draining the battery. Since you will either need the camera hooked up to electricity or constantly recharging batteries, you will not be saving any electricity. Then consider what if someone moves away from that wall, but is still in the room?





Don't forget that you will need some sort of control box that can interpret the signal from the camera and be able to turn the lights/fans on/off and that will need to be hardwired into the circuitry for that room. I won't even get into that hazards of doing that (knowing the total amps that the circuit will be powering and using components that can handle the load, fail safe in case of short circuit, etc.). Designing circuits like you want were not covered until the Bachelor Degree program in Electronic Engineering.

Answer 3

Would help if you shared what OS you're running on, in which language you want to write this and what kind of interface your camera has.