Optoelectronic imaging system which loaded on ships have several imaging channels generally. They can cover visible light (daylight and low-light), medium wave infrared and long wave infrared. To that systems have only two channels, visible light imaging is kept. In this paper, for the requirement of target real-time detection and classification under sea-sky background, image data from different channels are processed independently using Harris feature of targets and texture feature of background, then the result data from different channels are fused and compared to delete fake targets and interference from background, in order to reduce false alarm rate and improve the detection location precision. Based on the location relationship between targets and different type background (sky or sea), the target types are determined. For the rigidly requirement of system real time, multithread mechanism and big neighborhood processor are applied for parallel data processing, in order to reduce the processing time less than one frame time. At last, the experiment has been done on two channels system, approving that the method in this paper can improve the comprehensive searching performance of optoelectronic imaging system.