Survey of Image Denoising Methods using Double-Density Complex DWT

Abstract

Image denoising means removal of noise from an image and collect the remaining information from that image. A wavelet Transformation method is very widely used now days for noise removal. It provides multi resolution representation using a set of analyzing functions that are dilations and translations of a few functions. but the extensions of DWT are now widely used . In this paper basic introduction about the wavelet transformation and its extensions are provided. The wavelet based denoising method uses DWT (Discrete Wavelet Transform) suffers a lack of directionality and shift variance. To overcome this, CWT (Complex Wavelet Transform) can be used in two modes namely, Dual-Tree Complex DWT and Double-Density Complex DWT. In this paper, these two modes are compared.
Key Words: DWT, Dual-Tree Complex DWT, Double Density DWT