八向对称重用策略降低全景图像查表展开法查找表空间

为解决全景图像查表展开法所需查找表空间过大问题,提出八向对称重用的策略.首先,把展开前圆环状全景图像看作一系列同心圆环,沿圆心将这些圆环均匀划分成八个对称的扇形区域.然后,利用空间几何对称性原理,建立八个区域中像素点之间的对称变换关系,这样只需保存一个扇形区域的全景变换像素坐标映射结果,从而将查找表存储空间降低为原来的八分之一.嵌入式应用实验表明,与传统的全景图像查表展开方法相比,所提出方法不仅将所需查找表存储空间降低了8倍,而且将全景图像展开速度平均提高2.74倍.

Reduce Look-up Table Space in Panorama Unrolling of Catadioptric Omni-directional Images by Eight Direction Symmetry Reuse Strategy

In order to reduce the look-up table space in panorama unrolling of catadioptric omni-directional images,this paper present an eight direction symmetry reuse strategy.Firstly,we treat the original image to be unrolled as a series of co-centric circles,and uniformly partition them into eight parts of symmetrical sector regions along eight directions(namely top,bottom,left,right,top-left,top-right,bottom-left,bottom-right).Secondly,according to symmetry principle in spatial geometry,we construct the pixel symmetrical transform relations among these regions.So,it needs to look-up only one region of pixel coordination for panorama unrolling in the look-up table,which reduces seven-eighths of look-up table space compared with traditional methods.Compared with traditional look-up table unrolling method,experiments indicate that the new method reduces storage space to one-eighth of traditional requirement,at the same time,the new method improves the unrolling speed to 2.74 times.