Projection-Based Wavelet Denoising [Lecture Notes]
Please cite this item using this persistent URLhttp://hdl.handle.net/11693/21081
IEEE Signal Processing Magazine
- Research Paper 
Institute of Electrical and Electronics Engineers Inc.
In this lecture note, we describe a wavelet domain denoising method consisting of making orthogonal projections of wavelet (subbands) signals of the noisy signal onto an upside down pyramid-shaped region in a multidimensional space. Each horizontal slice of the upside down pyramid is a diamond shaped region and it is called an -ball. The upside down pyramid is called the epigraph set of the -norm cost function. We show that the method leads to soft-thresholding as in standard wavelet denoising methods. Orthogonal projection operations automatically determine the soft-threshold values of the wavelet signals. © 2015 IEEE.