有限脊波变换环绕现象改进算法及其在版权保护中的应用

摘要

Finite Ridgelet Transform(FRIT)能高效表示线的奇异特征,在多种领域广泛应用.但是由于它的"环绕"现象,影响了在图像处理中的应用.揭示了"环绕"现象和Finite Radon Transform(FRAT)域系数的关系,根据像素的空间相关性,以及对FRAT系数进行软门限阈值处理,提出一种改进算法,能够去除"环绕"现象.依据最大后验概率(MAP)准则选择大能量的改进有限脊波变换(Modified Finite Ridgelet Transform-MFRIT)系数,版权信息嵌入其中.实验结果表明,该算法具有更好的鲁棒性和透明性.%Finite Ridgelet Transform (FRIT) can effectively represent linear singularities in image, thus it is widely used in various fields.However, the limitation of wrap-around effect restricts its applications in image processing.Since the relation between wrap-around effect and distribution of FRAT (Finite Radon Transform) coefficients has been revealed, an improved algorithm which can remove the wrap-around effect is proposed through the spatial correlation of pixels and processing the soft threshold of FRAT coefficients.Copyright information is embedded in the MFRIT (Modified Finite Ridgelet Transform) coefficients which are selected according to maximum a posterior (MAP) estimating principle.Experimental result proves the relatively robustness and transparency.