改进型快速NEDI图像插值实现算法  

Improved fast new edge-directed fractional interpolation algorithm

作　　者：刘楠[1] 毕笃彦[1] 林嘉豪[1] 杨忠斌 

机构地区：[1]空军工程大学工程学院,西安710038 [2]中国航空工业集团第六三一研究所第一研究室,西安710068

出　　处：《计算机应用》2012年第7期1864-1867,共4页journal of Computer Applications

基　　金：国防科技重点实验室基金资助项目(9140C610301080C6106);国家自然科学基金资助项目(61175029)

摘　　要：针对经典新边缘指导插值(NEDI)算法存在的计算复杂度高、硬件实现困难、插值系数误差累计导致放大图像边缘噪声大的缺陷,提出一种改进的快速NEDI算法。算法采用圆形窗口计算插值系数,且该插值系数在高倍放大中可重复使用,避免了迭代计算插值系数引入的误差,并节省了迭代计算的时间。同时,对边缘区域非中心像素插值时,采用和被插点相邻的6个原像素点估计高分辨率图像的局部协方差。最后给出实验,并与双立方插值及经典NEDI算法进行比较。实验结果表明,使用改进算法插值后的图像边缘更加清晰,消除了大比例缩放时锯齿现象,提高了图像的视觉质量,计算复杂度也较经典NEDI算法大大降低。The original New Edge-Directed Interpolation（NEDI） algorithm is of high complexity,difficult for hardware implementation,and the interpolated images may suffer from blurring edges around edge area.To achieve a better subjective quality,an improved NEDI algorithm was proposed in this paper.In the new algorithm,a circular window was adopted,and the interpolation coefficient calculation was calculated only once,which could be reused in interpolating the center-pixels,thus the errors introduced by iterative computation were avoided and the interpolation time was saved.As to non-center pixels,six original neighbors were involved to estimate local covariance characteristics at high resolution.In comparison with the results of bi-cubic interpolation and the traditional NEDI,the experimental results indicate that proposed algorithm can eliminate the sawtooth of the interpolated picture in large-scale,and decrease the computational complexity.

关 键 词：新边缘指导插值 图像缩放 分数倍插值 插值系数 混合插值 

分 类 号：TP391.413[自动化与计算机技术—计算机应用技术]