A user device comprising: an encoder configured to receive video of one or more users (102a, 102b), from an image capture device, and to encode the video for transmission to at least another user device via a communication channel of a network, the communication channel being between the user device and another user device; a network interface configured to transmit the encoded video via the communication channel to the other user device; a resource manager configured to receive information about the communication channel between the user device and the other user device, wherein the received information comprises channel quality information, and, based on the received channel quality information, to determine a video resolution to be used for the video based on the received channel quality information, wherein the resource manager is configured to determine a higher video resolution if the received channel quality information indicates better channel quality and a lower video resolution if the received channel quality information indicates worse channel quality, wherein the encoder is configured to encode the video at the determined video resolution; and a video controller configured to select for a user in the video one or more user body parts from a plurality of user body parts based on the video resolution determined by the resource manager, and control the video based on detection of the selected user body parts to track the selected user body parts for the user by: processing the video before it is encoded to crop the video based on the detected user body parts, or controlling the image capture device to perform a zoom operation based on the detected body parts, wherein the video controller is configured to select and track more user body parts for the user at the higher video resolution and select and track fewer user body parts for the user at the lower video resolution. an encoder configured to receive video of one or more users (102a, 102b), from an image capture device, and to encode the video for transmission to at least another user device via a communication channel of a network, the communication channel being between the user device and another user device; a network interface configured to transmit the encoded video via the communication channel to the other user device; a resource manager configured to receive information about the communication channel between the user device and the other user device, wherein the received information comprises channel quality information, and, based on the received channel quality information, to determine a video resolution to be used for the video based on the received channel quality information, wherein the resource manager is configured to determine a higher video resolution if the received channel quality information indicates better channel quality and a lower video resolution if the received channel quality information indicates worse channel quality, wherein the encoder is configured to encode the video at the determined video resolution; and a video controller configured to select for a user in the video one or more user body parts from a plurality of user body parts based on the video resolution determined by the resource manager, and control the video based on detection of the selected user body parts to track the selected user body parts for the user by: processing the video before it is encoded to crop the video based on the detected user body parts, or controlling the image capture device to perform a zoom operation based on the detected body parts, wherein the video controller is configured to select and track more user body parts for the user at the higher video resolution and select and track fewer user body parts for the user at the lower video resolution.