Abstract: A surveillance system including a battery camera and a gateway. The battery camera includes a battery configured to supply power to the battery camera, a camera module configured to capture a surveillance area, a connector configured to directly connect to the gateway, a network module configured to communicate with the gateway, and a processor configured to charge the battery through the connector. The processor transmits high-quality images through the connector when the connector is connected to the gateway and transmits low-quality images through the network module when the connector is disconnected from the gateway.

Abstract: A camera apparatus includes: a main body, on which a camera is mounted, wherein the camera is configured to capture an image of a surveillance area; a first attachment member coupled to the main body, and configured to be coupled to a second attachment member coupled to an external device to connect the external device to the main body; and a hanger connected to the main body, the hanger having a ring shape that forms a closed loop along a hole formed on an inside of the ring shape, wherein the hanger extends outwards from a side surface of the main body.