이중 밀도 웨이브렛 변환의 성능 향상을 위한 3방향 분리 처리 기법

Abstract

This paper introduces the double­density discrete wavelet transform using 3 direction separable processing method, which is a discrete wavelet transform that combines the double­density discrete wavelet transform and quincunx sampling method, each of which has its own characteristics and advantages. The double­density discrete wavelet transform is nearly shift­invariant. But there is room for improvement because not all of the wavelets are directional. That is, although the double­density DWT utilizes more wavelets, some lack a dominant spatial orientation, which prevents them from being able to isolate those directions. The dual­tree discrete wavelet transform has a more computationally efficient approach to shift invariance. Also, the dual­tree discrete wavelet transform gives much better directional selectivity when filtering multidimensional signals. But this transformation has more cost complexity Because it needs eight digital filters. Therefor, we need to hybrid transform which has the more directional selection and the lower cost complexity. A solution to this problem is a the double­density discrete wavelet transform using 3 direction separable processing method. The proposed wavelet transformation services good performance in image and video processing fields.