Tunable-Q contourlet transform for image representation  

作　　者：Haijiang Wang Qinke Yang Rui Li Zhihong Yao 

机构地区：[1]Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources [2]College of Urban and Environment Science,Shanxi Normal University [3]College of Urban and Environmental Sciences,Northwest University [4]College of Resources and Environment,North China University of Water Resources and Electric Power

出　　处：《Journal of Systems Engineering and Electronics》2013年第1期147-156,共10页系统工程与电子技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(40971173;41071188)

摘　　要：A novel tunable-quality-factor （tunable-Q） contourlet transform for geometric image representation is proposed. The Laplacian pyramid in original contourlet decomposes a signal into channels that have the same bandwidth on a logarithmic scale, and is not suitable for images with different behavior in frequency domain. We employ a new tunable-Q decomposition defined in the frequency domain by which one can flexibly tune the bandwidth of decomposition channels. With an acceptable redundancy, this tunable-Q contourlet is also anti-aliasing and its basis is sharply localized in the desired area of frequency and spatial domain. Our experiments in nonlinear approximation and denoising show that the contourlet using a better-suitable quality factor can achieve a more promising performance and often outperform wavelets and the previous contourlets both in visual quality and in terms of peak signal-to-noise ratio.A novel tunable-quality-factor （tunable-Q） contourlet transform for geometric image representation is proposed. The Laplacian pyramid in original contourlet decomposes a signal into channels that have the same bandwidth on a logarithmic scale, and is not suitable for images with different behavior in frequency domain. We employ a new tunable-Q decomposition defined in the frequency domain by which one can flexibly tune the bandwidth of decomposition channels. With an acceptable redundancy, this tunable-Q contourlet is also anti-aliasing and its basis is sharply localized in the desired area of frequency and spatial domain. Our experiments in nonlinear approximation and denoising show that the contourlet using a better-suitable quality factor can achieve a more promising performance and often outperform wavelets and the previous contourlets both in visual quality and in terms of peak signal-to-noise ratio.

关 键 词：CONTOURLET quality factor （Q-factor） ANTI-ALIASING mul-tiscale decomposition. 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术] TN248.1[自动化与计算机技术—计算机科学与技术]