High Dynamic Range Real-time Vision System for Robotic Applications

Robotics applications often requires vision systems capable of capturing a large amount of information related to a scene. With many camera sensors, the perception of information is limited in areas with strong contrasts. The High Dynamic Range (HDR) vision system can deal with these limitations. This paper describes the HDR-ARtiSt hardware platform (High Dynamic Range Advanced Real-time imaging System), a FPGAbased architecture that can produce a realtime high dynamic range video from successive image acquisition. The proposed approach uses three captures with different exposure times, in a pure-hardware computationally efficient manner suitable for real-time processing. This method has the advantage to make outputs more visible than a simple single exposure. A real-time hardware implementation of High Dynamic Range video that shows more details in dark areas and bright areas of a scene is an important line of research. Our approach consists of three steps. First we capture three images from the sensor with alternating the three exposure times, and we store them into memory. Then we manage reading and writing operations in memory to have three video streams in parallel, corresponding to the three exposure times. Finally, under a highly parallel context, we blend the three video streams together with a modified version of the High Dynamic range technique. Our system can achieve an output at 60 fps with a full sensor resolution of 1, 280× 1, 024 pixels. We demonstrate the efficiency of our technique through a series of experiments and comparisons.