基於區間梯度的聯合雙邊濾波圖像紋理去除方法

圖像紋理去除是指保留圖像的語義結構並去除圖像中的紋理和雜訊部分，從而將紋理區域與結構特徵劃分開，是計算成像和圖像分析的基礎研究問題。近年來，在該領域中出現了許多優秀的演算法，但它們在結構紋理的區分效果、紋理濾除的乾淨程度和演算法運行的效率等方面仍存在一些問題和矛盾。鑒於此，提出一種基於區間梯度的濾波方法來去除圖像紋理。首先，為簡化先驗模型的複雜度，將區間梯度的概念應用到結構提取模型中，實現了紋理與結構的二元化標記，為下一步單獨對紋理區域進行濾波處理做準備。其次，針對複雜多變的紋理部分，將最值替換機制融入到聯合雙邊濾波演算法中，即在目標圖元的鄰域中選取顏色差異最大的圖元作為顏色權重分佈的中心點，使其在濾波過程中起主導作用。實驗證明，所提方法能應用於多種紋理圖像，可有效緩解強紋理去除與運算效率之間的矛盾，同時，因在達到相近紋理去除效果時所需反覆運算次數更少，其在同類濾波方法中取得了更好的邊緣保持效果。
Image texture removal is a fundamental problem in image processing. It aims to decompose an image into texture patterns and structure features. Many filters have been proposed for removing image textures. However, these techniques suffer from some problems in balancing the performance among texture distinction, texture removal and time efficiency. In this paper, an interval gradient-based filter was proposed to remove image textures. First, to simplify the prior model, interval gradient is employed to extract the structure features. And the binary map that separates the structures from texture is achieved, which will be used as a guidance image when the filtering texture regions are processed. Then, to deal with complicated texture patterns, the shift smoothing technique is incorporated into joint bilateral filtering, and the pixel possessing the maximal color difference with the target pixel is selected as the center point for color weight distribution, so that it can dominate the filtering process. Experiments show that the proposed method can be applied to various types of texture images, achieving both effective texture removal and high time efficiency. Moreover, this method can better preserve the edge features attributing to fewer iteration times required for obtaining similar results of texture removal. Copyright © 2018 重慶西南信息有限公司.