Feature point identification in sparse optical flow based tracking in a computer vision system

Patent metadata

Field	Value
Publication number	US-2024153105-A1
Application number	US-202418414772-A
Country	US
Kind code	A1
Filing date	Jan 17, 2024
Priority date	Dec 30, 2015
Publication date	May 9, 2024
Grant date	—

Abstract

A method for sparse optical flow based tracking in a computer vision system is provided that includes detecting feature points in a frame captured by a monocular camera in the computer vision system to generate a plurality of detected feature points, generating a binary image indicating locations of the detected feature points with a bit value of one, wherein all other locations in the binary image have a bit value of zero, generating another binary image indicating neighborhoods of currently tracked points, wherein locations of the neighborhoods in the binary image have a bit value of zero and all other locations in the binary image have a bit value of one, and performing a binary AND of the two binary images to generate another binary image, wherein locations in the binary image having a bit value of one indicate new feature points detected in the frame.

First claim

What is claimed is:

1 . A method comprising:
generating a first image to indicate locations of a first set of points detected based on a first frame, wherein the locations of the first set of points are indicated by a first value and a remainder of the first image is indicated by a second value; generating a second image to indicate neighborhoods each of which surrounds one point of a second set of points detected based on a second frame, wherein the neighborhoods are indicated in the second image by the second value and a remainder of the second image is indicated by the first value; and generating a third image based on the first image and the second image to indicate locations of a subset of the first set of points that are excluded from the neighborhoods, wherein the locations of the subset of the first set of points are indicated by a value different from a remainder of the third image.

2 . The method of claim 1 , wherein the second frame is captured prior to the first frame.

3 . The method of claim 1 , comprising:
determining a set of coordinates for each point of the subset of the first set of points based on the third image.

4 . The method of claim 1 , wherein each of the neighborhoods corresponds to a N×N pixel area, and N is an integer.

5 . The method of claim 1 , wherein the first set of points corresponds to a first set of feature points detected within the first frame, and wherein the second set of points corresponds to a second set of feature points detected within the second frame.

6 . The method of claim 1 , wherein the first value is a first binary value and the second value is a second binary value.

7 . The method of claim 6 , wherein the first binary value is a binary one and the second binary value is a binary zero.

8 . The method of claim 7 , wherein generating the third image comprises performing a binary AND operation between the first image and the second image.

9 . A non-transitory computer readable medium storing instructions that, when executed by one or more processors, cause the one or more processors to:
generate a first image to indicate locations of a first set of points detected based on a first frame, wherein the locations of the first set of points are indicated by a first value and a remainder of the first image is indicated by a second value; generate a second image to indicate neighborhoods each of which surrounds one point of a second set of points detected based on a second frame, wherein the neighborhoods are indicated in the second image by the second value and a remainder of the second image is indicated by the first value; and generate a third image based on the first image and the second image to indicate locations of a subset of the first set of points that are excluded from the neighborhoods, wherein the locations of the subset of the first set of points are indicated by a value different from a remainder of the third image.

10 . The non-transitory computer readable medium of claim 9 , wherein the second frame is captured by a camera prior to the first frame.

11 . The non-transitory computer readable medium of claim 9 , wherein to generate the third image, the instructions cause the one or more processors to:
determine a set of coordinates for each point of the subset of the first set of points based on the third image.

12 . The non-transitory computer readable medium of claim 9 , wherein each of the neighborhoods corresponds to a N×N pixel area, and N is an integer.

13 . The non-transitory computer readable medium of claim 9 , wherein the first value is a first binary value and the second value is a second binary value.

14 . The non-transitory computer readable medium of claim 13 , wherein the first binary value is a binary one and the second binary value is a binary zero.

15 . The non-transitory computer readable medium of claim 14 , wherein to generate the third image, the instructions cause the one or more processors to:
perform a binary AND operation between the first image and the second image.

16 . A system, comprising:
memory storing instructions; and one or more processors configured to execute the instructions to:
generate a first image to indicate locations of a first set of points detected based on a first frame, wherein the locations of the first set of points are indicated by a first value and a remainder of the first image is indicated by a second value;
generate a second image to indicate neighborhoods each of which surrounds one point of a second set of points detected based on a second frame, wherein the neighborhoods are indicated in the second image by the second value and a remainder of the second image is indicated by the first value; and
generate a third image based on the first image and the second image to indicate locations of a subset of the first set of points that are excluded from the neighborhoods, wherein the locations of the subset of the first set of points are indicated by a value different from a remainder of the third image.

17 . The system of claim 16 , wherein each of the neighborhoods corresponds to a N×N pixel area centered around the one point of the second set of points, and N is an integer.

18 . The system of claim 16 , wherein the first value is a first binary value and the second value is a second binary value.

19 . The system of claim 18 , wherein the first binary value is a binary one and the second binary value is a binary zero.

20 . The system of claim 19 , wherein to generate the third image, the one or more processors are configured to execute the instructions to:
perform a binary AND operation between the first image and the second image.

Assignees

• Texas Instruments Inc

Inventors

• Poddar Deepak Kumar
• Jain Anshu
• Kumar Desappan
• Swami Pramod Kumar

Classifications

• G06T7/246 Primary

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

• G06T2200/28

  involving image processing hardware · CPC title

• G06T2207/20016

  Hierarchical, coarse-to-fine, multiscale or multiresolution image processing; Pyramid transform · CPC title

• G06T2207/30241

  Trajectory · CPC title