In this paper, we propose a simple and robust local descriptor, called the robust local binary pattern (RLBP). The local binary pattern (LBP) works very successfully in many domains, such as texture classification, human detection and face recognition. However, an issue of LBP is that it is not so robust to the noise present in the image. We improve the robustness of LBP by changing the coding bit of LBP. Experimental results on the Brodatz and UIUC texture databases show that RLBP impressively outperforms the other widely used descriptors (e.g., SIFT, Gabor, MR8 and LBP) and other variants of LBP (e.g., completed LBP), especially when we add noise in the images. In addition, experimental results on human face recognition also show a promising performance comparable to the best known results on the Face Recognition Grand Challenge (FRGC) face dataset.
IntroductionRecently, many sparse and dense descriptors (e.g., SIFT, Gabor, MR8 and LBP) have been proposed for different kinds of applications. There are several studies to evaluate their performance, e.g., [13,14]. LBP [15] is perhaps the best performing dense descriptor and it has been widely used in various applications, such as texture classification, human detection and face recognition [18]. It has been proven to be highly discriminative and its key advantages, namely its invariance to monotonic gray level changes and computational efficiency, make it suitable for demanding image analysis tasks.However, one issue of LBP is that it is not so robust to the noise present in images when the gray-level changes resulting from the noise are not monotonic, even if the changes are not significant [2]. To this end, we propose a new descriptor based on LBP, i.e., robust local binary pattern (RLBP). The idea is to locate the possible bit in LBP pattern changed by the noise and then revise the changed bit of the LBP pattern. The idea is very simple, but it works very well. For example, the performance of LBP decreases significantly when we add white Gauss noise in the Brodatz texture dataset [1]. However, the performance of RLBP almost does not change. We also add noise in UIUC texture [7] and FRGC face datasets [17] to testify the performance of RLBP.