User interface controlled by hand gestures above a desktop or a keyboard

A controller system for a computer, wherein the computer comprises a display element and an operation system, the controller system comprising:

• interaction surface located in front of the display element;
• one or more video cameras wherein the one or more video cameras have fields of view in which fields of view the interaction surface is included;
• gesture-recognition system with the capability of interpreting one or more gestures generated by one or more users, wherein the gesture-recognition system comprises logic which determines gestures from video data provided by the one or more video cameras and which logic determines one or more gestures based on at least one of the position, movement, orientation and shape properties of one or more predetermined objects within the video data;
• capability of initiating one or more predetermined events when one or more gestures are determined by the gesture-recognition system, wherein the one or more predetermined events is one or more of the following:
• changing mode of operation of the controller system, control of a cursor, scrolling, zooming view, panning view, pressing a virtual button, character input, virtual icon input, clicking, double-clicking, launching a computer application, providing input for a computer application, changing one or more settings of the operation system of the computer, changing one or more settings of a computer application, switching between applications, expressing emotion on a social media platform.