Image and Video Processing and Communications Lab (ivPCL), Department of Electrical Engineering and Computer Engineering, University of New Mexico, Albuquerque, NM 87131 USA.
IEEE Trans Image Process. 2010 May;19(5):1138-52. doi: 10.1109/TIP.2010.2040446. Epub 2010 Jan 12.
We develop new multiscale amplitude-modulation frequency-modulation (AM-FM) demodulation methods for image processing. The approach is based on three basic ideas: (i) AM-FM demodulation using a new multiscale filterbank, (ii) new, accurate methods for instantaneous frequency (IF) estimation, and (iii) multiscale least squares AM-FM reconstructions. In particular, we introduce a variable-spacing local linear phase (VS-LLP) method for improved instantaneous frequency (IF) estimation and compare it to an extended quasilocal method and the quasi-eigen function approximation (QEA). It turns out that the new VS-LLP method is a generalization of the QEA method where we choose the best integer spacing between the samples to adapt as a function of frequency. We also introduce a new quasi-local method (QLM) for IF and IA estimation and discuss some of its advantages and limitations. The new IF estimation methods lead to significantly improved estimates. We present different multiscale decompositions to show that the proposed methods can be used to reconstruct and analyze general images.
我们开发了新的多尺度调幅调频(AM-FM)解调方法,用于图像处理。该方法基于三个基本思想:(i)使用新的多尺度滤波器组进行 AM-FM 解调,(ii)用于瞬时频率(IF)估计的新的、准确的方法,以及(iii)多尺度最小二乘 AM-FM 重建。特别是,我们引入了一种可变间隔局部线性相位(VS-LLP)方法,用于改进瞬时频率(IF)估计,并将其与扩展准局部方法和准本征函数逼近(QEA)进行比较。结果表明,新的 VS-LLP 方法是 QEA 方法的推广,我们选择最佳的整数间距作为频率的函数进行自适应。我们还引入了一种用于 IF 和 IA 估计的新准局部方法(QLM),并讨论了它的一些优点和局限性。新的 IF 估计方法导致了显著改进的估计。我们提出了不同的多尺度分解,以表明所提出的方法可用于重建和分析一般图像。