3D Object Detection and Pose Estimation

1. Problem Description

3D object detection and pose estimation often requires a 3D object model, and even so, it is a difficult problem if the object is heavily occluded in a cluttered scene. In this project, we introduce a novel approach for recognizing and localizing 3D objects based on their appearances through segmentation of 3D surfaces. The approach can identify multiple occluded objects in a scene, which may include different instances of the same object, and estimate the pose of each entire object even if the object can only be seen partially due to occlusion.

2. Surface-based Object Representation

We start from a sufficient number of RGB-D images of different viewpoints of an object (captured by Microsoft Kinect) in order to establish an appearance-based representation of the object. First, images are segmented based on smooth surfaces, where a smooth surface is defined by the continuity of depth and surface normal values, and its boundary is characterized by depth and surface normal
discontinuity. Each object is characterized in terms of surface segments from multiple views and the visual signatures of the surface segments. As an example, Fig. 1 shows a common cereal box and its smooth 3D geometric surfaces in terms of the corresponding image segments from different views.

Figure 1: A common cereal box and images of its smooth 3D surfaces from different views

In the representation of an object, after surface segments are obtained from all images of different views, key point matching is then conducted to establish correspondence among surface segments of the same 3D smooth object surface in different images. A coarse 3D model of the entire object is next established based on the matching results, and an object frame (i.e., coordinate system) is specified1 . This
is done by applying SVD  and RANSAC algorithms. Fig. 2 shows some reconstruction results.

Figure 2: Examples of reconstructed objects, from left to right: cereal box, cup noodle, milk box 1 and milk box 2
Figure 2: Examples of reconstructed objects, from left to right: cereal box, cup noodle, milk box 1 and milk box 2

3. Experiments

Fig. 3 shows the results of our approach for object detection and pose estimation for the example test images.

Figure 3: Examples of object detection and pose estimation results: each row starting with an original test image followed by four images from left, back, right, and top views that display the corresponding reconstructed scene.

More details can be found in this paper:

• Zhou Teng and Jing Xiao, “Surface-based General 3D Object Detection and Pose Estimation”, in IEEE International Conference on Robotics and Automation (ICRA), Pages 5473-5479, Hong Kong, China, 2014. (PDF)