摘要
为了更好地进行快速插值,提出一种改进的沃尔什滤波器:首先研究了传统的Walsh变换及其性质,在此基础上推导出Walsh滤波模板的设计方法;其次由于Walsh模板仅有4×4大小,因此给出一种基于权值矩阵的拼合方法;最后,对上千幅图像进行测试,求解出最佳权值a=1.6,b=0.8。实验将5幅标准测试图像分为两组,分别进行1/2抽取与1/4抽取,得到的插值结果均表明算法的插值效果优于最近邻插值、三次插值、区域坐标三次插值法、Walsh插值。同时,时间分析表明,算法的运行时间与三次插值相当。
In order to interpolate images more efficiently,an improved Walsh filter is proposed.Firstly traditional Walsh trans-form and its properties are investigated,and the model-design method based on Walsh transform is deducted.Secondly,since the size of the interpolation model is only 4×4,a novel method based on weight matrix is proposed to use a larger window. Finally,the weights are obtained by calculation on thousands of images where a=1.6 and b=0.8.Five standard test images are divided into 2 groups,and each group is performed 1/2,1/4 sample respectively,and then interpolated by different algorithms. All interpolated images demonstrate that this proposed algorithm is superior to nearest interpolation,cubic interpolation,CIVA method,and Walsh interpolation.Moreover,the time analysis shows that the computation time of this algorithm is nearly equal to cubic interpolation.
出处
《计算机工程与应用》
CSCD
北大核心
2011年第9期156-159,174,共5页
Computer Engineering and Applications
基金
国家自然科学基金(No.60872075)
国家高技术研究发展计划(863)(No.2008AA01Z227)
高等学校科技创新工程重大项目培育资金项目(No.706028)
江苏省自然科学基金(No.BK2007103)
东南大学优秀博士学位论文基金(No.YBJJ0908)~~
关键词
图像插值
沃尔什变换
滤波器
权值矩阵
image interpolation
Walsh transform
filter
weight matrix
