基于数字滤波的B-样条插值法在图像旋转中的应用  

Application of B-Spline Interpola tion Based on Digital Filter in Image Rotation

作　　者：李开宇[1] 张焕春[1] 经亚枝[1] 

机构地区：[1]南京航空航天大学自动化学院,南京210016

出　　处：《南京航空航天大学学报》2004年第5期633-638,共6页Journal of Nanjing University of Aeronautics & Astronautics

摘　　要：提出一种基于无限脉冲响应和有限脉冲响应数字滤波技术的快速 B-样条插值法 ,并将其应用于实时图像旋转处理中。为了优化旋转后的图像质量 ,本文采用 3次 B-样条对图像旋转后的像素点灰度值进行插值运算。另外 ,通过对传统图像旋转矩阵的分解 ,将图像在二维空间中的旋转运算分解成为三步在一维空间内平移运算 ,使插值运算在一维空间中完成 ,从而简化了图像旋转数据处理中的插值运算。最后 ,还提出了一种以硬件方法完成高阶图像插值运算实现图像旋转的新方法 ,并针对 2 5 6灰度级 ,2 5 6× 2 5 6像素的图像 ,设计出一个以 FPGA为核心的实时、高质量的硬件图像旋转系统。An IIR -based and FIR-based digital filter to realize fast cubic B-spline interpolat ion is deve-loped and applied in image rotation system. In order to ensure high quality of the rotated image, the cubic B-spline interpolation to calculate th e gray of pixels of the rotated image is adopted. What is more, the approach of decomposition of a two-dimensional rotation into three-step one-dimensional s hift by decomposing the traditional matrix of image rotation is introduced, whic h succeeds in simplifying the interpolation of image rotation. A new approach to achieve the high-order interpolation and to realize the rotation of images is also developed by the hardware. And it designs a FPGA-based fast and high quali ty image rotation system for the 256×256 pixels images in 256 gray levels.

关 键 词：B-样条插值 数字滤波 图像旋转 现场可编程门阵列 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]