Method and apparatus for processing point cloud data

Patent metadata

Field	Value
Publication number	US-11037305-B2
Application number	US-201816235668-A
Country	US
Kind code	B2
Filing date	Dec 28, 2018
Priority date	Dec 29, 2017
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

Implementations of the present disclosure can include a method and apparatus for processing point cloud data. Specifically, the method for processing point cloud data can be provided, including: acquiring a first frame and a second frame respectively from the point cloud data; extracting a first candidate object from the first frame and a second candidate object corresponding to the first candidate object from the second frame, respectively; determining a first location of the first candidate object and a second location of the second candidate object in a coordinate system of the point cloud data, respectively; and identifying any one of the first candidate object and the second candidate object as a moving object, in response to an offset between the first location and the second location.

First claim

What is claimed is:

1. A method for processing point cloud data, the method comprising:
acquiring a first frame and a second frame respectively from the point cloud data;
from a plurality of objects in the first and second frames, extracting a first candidate object in the first frame and a second candidate object corresponding to the first candidate object in the second frame, respectively;
determining a first location of the first candidate object and a second location of the second candidate object in a coordinate system of the point cloud data, respectively;
identifying any one of the first candidate object and the second candidate object as a moving object in response to determining an offset between the first location and the second location;
removing the moving object from the point cloud data; and
generating a three-dimensional map based on the point cloud data from which the moving object is removed,
wherein extracting the first candidate object and the second candidate object comprises:
detecting a first ground object in the first frame and a second ground object in the second frame, respectively;
comparing a first height of a first object in the first frame with a first ground object height of the first ground object, and comparing a second height of a second object in the second frame with a second ground object height of the second ground object;
determining objects connected to one of the first ground object in the first frame and the second ground object in the second frame based on the comparing;
forming a first set of candidate objects and a second set of candidate objects respectively based on the objects connected to one of the first ground object in the first frame and the second ground object in the second frame; and
selecting the first candidate object from the first set of candidate objects, and selecting the second candidate object corresponding to the first candidate object from the second set of candidate objects,
wherein the extracting reduces computation associated with identification of the moving object from the plurality of objects in the first and second frames, and

wherein the method is performed by at least one processor.

2. The method according to claim 1 , wherein the selecting the second candidate object from the second set of candidate objects comprises:
selecting the second candidate object corresponding to the first candidate object based on a size ratio of the first candidate object to the second candidate object.

3. The method according to claim 1 , wherein the selecting the second candidate object from the second set of candidate objects comprises:
acquiring a first image associated with the first frame and a second image associated with the second frame, respectively; and
selecting the second candidate object based on determining that the second candidate object in the second image matches the first candidate object in the first image.

4. The method according to claim 1 , wherein the identifying the first candidate object as the moving object comprises:
acquiring a third frame from the point cloud data;
extracting a third candidate object corresponding to the first candidate object in the third frame; and
identifying any one of the first candidate object, the second candidate object, and the third candidate object as the moving object in response to determining that a third location of the third candidate object in the coordinate system is associated with the offset.

5. The method according to claim 4 , wherein the identifying any one of the first candidate object, the second candidate object, and the third candidate object as the moving object comprises:
determining a predicted location of the third candidate object in the coordinate system; and
identifying any one of the first candidate object, the second candidate object, and the third candidate object as the moving object in response to the predicted location being consistent with the third location.

6. The method according to claim 5 , wherein the determining the predicted location of the third candidate object in the third frame comprises:
determining an object speed of the first candidate object based on the offset; and
determining the predicted location based on the object speed.

7. The method according to claim 1 , further comprising:
determining, based on the first candidate object and the second candidate object, a set of points associated with the moving object in the point cloud data; and
removing the set of points from the point cloud data.

8. The method according to claim 7 , wherein the determining the set of points associated with the moving object further comprises:
determining, in a plurality of frames of the point cloud data, the set of frames associated with the moving object;
determining a motion trajectory of the moving object based on locations of the moving object in the set of frames; and
determining the set of points associated with the moving object based on the motion trajectory.

9. An apparatus for processing point cloud data, the apparatus comprising:
at least one processor; and
a memory storing instructions, wherein the instructions when executed by the at least one processor, cause the at least one processor to perform operations, the operations comprising:
acquiring a first frame and a second frame respectively from the point cloud data;
from a plurality of objects in the first and second frames, extracting a first candidate object in the first frame and a second candidate object corresponding to the first candidate object in the second frame, respectively;
determining a first location of the first candidate object and a second location of the second candidate object in a coordinate system of the point cloud data, respectively;
identifying any one of the first candidate object and the second candidate object as a moving object in response to determining an offset between the first location and the second location;
removing the moving object from the point cloud data; and
generating a three-dimensional map based on the point cloud data from which the moving object is removed,
wherein extracting the first candidate object and the second candidate object comprises:
detecting a first ground object in the first frame and a second ground object in the second frame, respectively;
comparing a first height of a first object in the first frame with a first ground object height of the first ground object, and comparing a second height of a second object in the second frame with a second ground object height of the second ground object;
determining objects connected to one of the first ground object in the first frame and the second ground object in the second frame based on the comparing;
forming a first set of candidate objects and a second set of candidate objects respectively based on the objects connected to one of the first ground object in the first frame and the second ground object in the second frame; and
selecting the first candidate object from the first set of candidate objects, and selecting the second candidate object corresponding to the first candidate object from the second set of candidate objects,
wherein the extracting reduces computation associated with identification of the moving object from the plurality of objects in the first and second frames.

10. The apparatus according to claim 9 , wherein the selecting the second candidate object from the second set of candidate objects comprises:
selecting the second candidate object corresponding to the first candidate object based on a size ratio of the first candidate object to the second candidate object.

11. The apparatus according to claim 9 ,

Assignees

• Baidu online network technology beijing co ltd

Inventors

• Zhan Yifei
• Yan Miao
• Zhou Wang
• Duan Xiong
• Lang Xianpeng
• Ma Changjie

Classifications

• G01S7/4802 Primary

  using analysis of echo signal for target characterisation; Target signature; Target cross-section · CPC title

• G06T7/246 Primary

  using feature-based methods, e.g. the tracking of corners or segments · CPC title

• G06F18/23

  Clustering techniques · CPC title

• G06V20/49

  Segmenting video sequences, i.e. computational techniques such as parsing or cutting the sequence, low-level clustering or determining units such as shots or scenes · CPC title

• G01S17/931

  of land vehicles · CPC title