Point cloud saliency detection via local sparse coding

Abstract

The human visual system (HVS) can process large quantities of visual information instantly. Visual saliency perception is the process of locating and identifying regions with a high degree of saliency from a visual standpoint. Mesh saliency detection has been studied extensively in recent years, but few studies have focused on 3D point cloud saliency detection. The estimation of visual saliency is important for computer graphics tasks such as simplification, segmentation, shape matching and resizing. In this paper, we present a method for the direct detection of saliency on unorganized point clouds. First, our method computes a set of overlapping neighborhoods and estimates adescriptor vector for each point inside it. Then, the descriptor vectors are used as a natural dictionary in order to apply a sparse coding process. Finally, we estimate a saliency map of the point neighborhoods based on the Minimum Description Length (MDL) principle.Experiment results show that the proposed method achieves similar results to those from the literature review and in some cases even improves on them. It captures the geometry of the point clouds without using any topological information and achieves an acceptable performance. The effectiveness and robustness of our approach are shown by comparing it to previous studies in the literature review.

A Saliency-Based Sparse Representation Method for Point Cloud Simplification

“…Figure 2 shows the saliency levels found in the vector ; to visualize it, we use a threshold with different values. Equation (14), was proposed by [ 27 ] in a local context, and the present work is a generalization to use it globally.…”

“…Figure 2 shows the saliency levels found in the vector S f ; to visualize it, we use a threshold T with different values. Equation ( 14), was proposed by [27] in a local context, and the present work is a generalization to use it globally. nonzero elements-implying that a linear combination of many atoms is required to represent the point correctly-and if its sparse reconstruction error − produces a high residual.…”