In a video surveillance system comprising a plurality of recording servers, each storing video data received from at least one video surveillance camera, a method of processing requests for thumbnail images comprises receiving a thumbnail request to a main queue 200. The thumbnail request includes information indicating a specific video camera and a specific recording server. The thumbnail request is allocated to a recording server queue 250 corresponding to the specific recording server. It is determined whether an idle resource processor 260 associated with the recording server queue is available to process the thumbnail request. If no idle resource processor is available, then it is determined how many resource processors are associated with the recording server queue and, if this is less than a maximum number, a new resource processor is initiated for processing the thumbnail request and the new resource processor is put into an idle state after processing the thumbnail request.