Design of 2D directional adaptive filter banks and its application to image coding

在这项研究中，我们提出了一种用于离散小波变换的二维不可分离自适应方向提升(ADL)结构及其在图像编码中的应用。虽然9/7DWT的二维不可分提升结构是通过交换一些提升而提出的，但我们推广了小波变换的二维不可分提升结构的多相表示。此外，通过在广义结构中引入自适应方向滤波，实现了二维不可分ADL结构，并将其应用于图像编码。我们提出的方法比一维ADL更简单，并且可以与一维ADL一起选择不同的变换方向。仿真结果表明，该方法在有损和无损的图像编码性能方面是有效的。

In this research, we propose a two dimensional(2D) non-separable adaptive directional lifting(ADL) structure for discrete wavelet transform(DWT) and its image coding application. Although a 2D non-separable lifting structure of 9/7 DWT has been proposed by interchanging some lifting, we generalize a polyphase representation of 2D non-separable lifting structure of DWT. Furthermore, by introducing the adaptive directional filteringing to the generalized structure, the 2D non-separable ADL structure is realized and applied into image coding. Our proposed method is simpler than the 1D ADL, and can select the different transforming direction with 1D ADL. Through the simulations, the proposed method is shown to be efficient for the lossy and lossless image coding performance.