Reduce Look-up Table Space in Panorama Unrolling of Catadioptric Omni-directional Images by Eight Direction Symmetry Reuse Strategy
Shaohua Liu · Journal of Chinese Computer Systems · 2007
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.