Research and implementation of large field image real-time mosaic technology based on FPGA

As a general rule, the software method is used to obtain large field images, which is not timely and convenient. In order to tackle the disadvantage of this method, based on FPGA, a kind of programmable technologies, a large field of view imaging system had put forward and achieved, which can fulfill the real time stitching of the data from multiple cameras. Through the APTINA's color CMOS image sensor MT9M034, the original image information had gained and then the real time data collection, data cache, stitching and transmission had accomplished centering on the Xilinx's Virtex-5 FPGA. Firstly, the automatic adjustment of brightness differences of the original images was preprocessed in order to improve the overall mosaic effect. Secondly, information detection of relative shift amount was completed by the use of phase correlation method to register the original images. Finally, the two adjacent images' overlap area was fused by the use of linear weighted fusion algorithm to make the mosaic image achieve a smoothly fading in and out transitional effect. Experimental results show that the imaging system is simple and reliable, and can effectively increase the field of view of observation. The stitched large field images are of high-definition and real time, with a certain degree of representativeness and practicality.