Method and system for controlling lighting

A lighting system comprising

• control circuit having an output for controlling intensity and/or spectral content of a plurality of controllable light sources, the control circuit being configured to adjust the intensity and/or spectral content dependent on position information indicative of a position of a object relative to the controllable light sources;
• an image processing circuit with an input for receiving images from an image sensor, and an output for supplying the position information to the control circuit, the processing circuit being configured to detect in an image from said image sensor whether light from a selected one of the controllable light sources to points shown at respective image positions in said image has been temporarily intercepted by an object, to determine information indicative of a direction of the intercepting object relative to the selected one of the controllable light sources from the respective image positions where the light has been detected to be intercepted, and to update the position information according to the direction determined from the respective image positions where the light has been detected to be intercepted, wherein the image processing circuit is further configured for computing information representing a direction of a line through an image position corresponding to a position of the selected one of the controllable light sources to the respective image positions where the light has been detected to be intercepted, and for determining the information indicative of a direction of the intercepting object relative to the selected one of the controllable light sources from the information representing the direction of said line.

An image processing device comprising an input unit for receiving images from an image sensor, and an output unit for outputting position information indicative of a position of a object relative to controllable light sources, the device being configured for detecting in an image from said image sensor whether light from a selected one of the controllable light sources to points shown at respective image positions in said image has been temporarily intercepted by an object, wherein the detecting includes comparing pixel values from the image with reference values for the respective image positions, for determining information indicative of a direction of the intercepting object relative to the selected one of the controllable light sources from the respective image positions where the light has been detected to be intercepted, and for updating the position information according to the direction determined from the respective image positions where the light has been detected to be intercepted, wherein the image processing device is further configured for

• changing the lighting parameters of the selected one of the controllable light sources,
• capturing a further image, the selected one of the controllable light sources having mutually different lighting parameters at times of capturing the image and the further image respectively;
• computing differences between image values in the image and the further image;
• and
• performing said detecting by comparing the differences for the respective image positions with reference values.