Method for calculating information relative to a relative speed between an object and a camera

Patent metadata

Field	Value
Publication number	US-11836933-B2
Application number	US-201917627281-A
Country	US
Kind code	B2
Filing date	Jul 18, 2019
Priority date	Jul 18, 2019
Publication date	Dec 5, 2023
Grant date	Dec 5, 2023

Abstract

A method includes calculating a stereo-disparity map between the initial image and the final image, for each column of the stereo-disparity map, calculating an average value of the stereo-disparities of the pixels of the column, calculating the slope and/or constant factor of a linear function approximating variations of said average values; and calculating said information relative to the relative speed between the object and the camera, based on the slope and/or the constant factor.

First claim

The invention claimed is:

1. A computer-implemented method for calculating information relative to a relative speed between an object and a camera, based on an initial image and a final image of the object, derived from image frames outputted by the camera, the initial image and final image having the same pixel-size, the method comprising:
calculating a stereo-disparity map between the initial image and the final image;
for each column of the stereo-disparity map, calculating an average value of the stereo-disparities of pixels of the column;
calculating a slope and/or a constant factor of a linear function approximating variations of the average values; and
calculating the information relative to the relative speed between the object and the camera, based on the slope and/or the constant factor.

2. A non-transitory computer-readable medium storing instructions that, when executed by a processor, cause the processor to perform a computer program including instructions to perform a method according to claim 1 .

3. A control method for a vehicle, the vehicle comprising a camera configured to acquire images, the control method comprising:
acquiring camera images of an environment of the vehicle with the camera;
identifying an object in at least a pair of the camera images;
extracting an initial object image and a final object image which are portions of the pair of camera images defined by a bounding box of the identified object;
calculating information relative to a relative speed between an object and the camera, using a method according to claim 1 ; and
controlling at least one vehicle device of the vehicle based on the information relative to the relative speed between the object and the camera.

4. A non-transitory computer-readable medium storing instructions that, when executed by a processor, cause the processor to perform a computer program including instructions to perform a method according to claim 3 .

5. An automated driving system for a vehicle, the automated driving system comprising an electronic control unit configured to, based on an initial image and a final image of an object, derived from image frames outputted by a camera, the initial image and final image having the same pixel-size:
calculate a stereo-disparity map between the initial image and the final image;
for each column of the stereo-disparity map, calculate an average value of the stereo-disparities of pixels of the column;
calculate a slope and/or a constant factor of a linear function approximating variations of the average values; and
calculate information relative to a relative speed between the object and the camera, based on the slope and/or the constant factor.

6. The automated driving system according to claim 5 , further comprising a camera configured to be mounted on a vehicle; and the electronic control unit is configured to:
acquire camera images of an environment of the vehicle with the camera;
identify an object in at least a pair of the camera images;
extract an initial object image and a final object image which are portions of the pair of camera images defined by a bounding box of the identified object; and
output a command for at least one vehicle device of the vehicle based on the information relative to the relative speed between the object—and the camera.

Assignees

• Toyota Motor Europe

Inventors

• Chumerin Nikolay

Classifications

• G06T7/246 Primary

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

• G06T7/215

  Motion-based segmentation · CPC title

• G06T7/285

  using a sequence of stereo image pairs · CPC title

• G06T7/292

  Multi-camera tracking · CPC title

• G06V20/58

  Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads · CPC title