A high performance processing system for event identification and centroiding to be used in a photon counting detector for space applications is presented. In order to satisfy the processing requirements dictated by the identification problem, an ad-hoc system based on Field Programmable Gate Arrays (FPGAs) has been designed. FPGAs are shown able to achieve the best performance required by the envisioned application, as compared to former systems based on alternative off-the-shelf technologies. FPGAs also allow matching low design and development costs with the requirements of fast identification and flexibility in adequating the system to ever increasing counting rates, and in implementing more sophisticated centroiding algorithms.