A detection system for determining a repeating first sequence ofN symbols included in a first code, wherein the first code is embedded into a light output of a first light source of an illumination system, the detection system comprising: a camera configured to acquire a series of images of a scene, the camera having a frame time, wherein: each acquired image includes a plurality of pixels, each pixel representing an intensity of a total light output of the illumination system at a different physical position within the scene and the total light output of the illumination system comprises the light output of the first light source in at least one physical position within the scene, characterized in that: the series comprises at least N different images, and each image of the at least N different images is acquired with a total exposure time comprising one or more exposure instances, wherein in each of the N different images, the one or more exposure instances are at different temporal positions relative to the repeating first sequence of N symbols, wherein, for each image, the total exposure time is less than the frame time of the camera; and a processing unit configured to process the acquired series of images to determine the repeating first sequence of N symbols. a camera configured to acquire a series of images of a scene, the camera having a frame time, wherein: each acquired image includes a plurality of pixels, each pixel representing an intensity of a total light output of the illumination system at a different physical position within the scene and the total light output of the illumination system comprises the light output of the first light source in at least one physical position within the scene, characterized in that: the series comprises at least N different images, and each image of the at least N different images is acquired with a total exposure time comprising one or more exposure instances, wherein in each of the N different images, the one or more exposure instances are at different temporal positions relative to the repeating first sequence of N symbols, wherein, for each image, the total exposure time is less than the frame time of the camera; and each acquired image includes a plurality of pixels, each pixel representing an intensity of a total light output of the illumination system at a different physical position within the scene and the total light output of the illumination system comprises the light output of the first light source in at least one physical position within the scene, characterized in that: the series comprises at least N different images, and each image of the at least N different images is acquired with a total exposure time comprising one or more exposure instances, wherein in each of the N different images, the one or more exposure instances are at different temporal positions relative to the repeating first sequence of N symbols, wherein, for each image, the total exposure time is less than the frame time of the camera; and the series comprises at least N different images, and each image of the at least N different images is acquired with a total exposure time comprising one or more exposure instances, wherein in each of the N different images, the one or more exposure instances are at different temporal positions relative to the repeating first sequence of N symbols, wherein, for each image, the total exposure time is less than the frame time of the camera; and a processing unit configured to process the acquired series of images to determine the repeating first sequence of N symbols.