Method for detecting traffic signs

Patent metadata

Field	Value
Publication number	US-10885358-B2
Application number	US-201716300390-A
Country	US
Kind code	B2
Filing date	May 8, 2017
Priority date	May 10, 2016
Publication date	Jan 5, 2021
Grant date	Jan 5, 2021

Abstract

The limitation, which applies when capturing traffic signs in a conventional manner using a camera which is oriented to the front with respect to the vehicle, to capturing traffic signs that are located ahead in the driving direction and the unique association between traffic signs that apply only to one direction and the driving direction of the capturing vehicle are eliminated by way of a camera that is oriented to the rear with respect to the vehicle, for example a rear-view camera of the vehicle, also being operated during forward travel in order to also capture traffic signs that apply to the opposite direction and are located behind the vehicle at the time they are captured, and the position of said traffic signs, and by way of data sets generated therefrom being transmitted to the database together with the data sets generated by means of the front camera.

First claim

The invention claimed is:

1. A method for capturing traffic signs and the placement site of said traffic signs by a driving vehicle, comprising:
periodically or continuously determining a geographic position of the vehicle, respect to the vehicle,
performing image recognition on the images recorded using the first camera in an image region located in a region of the opposite lane, wherein the image recognition marks objects having a typical shape of traffic signs as candidates,
estimating a time at which one of the candidates enters the capturing region of a second camera and the location in the image at which entry occurs;
recording images using the second camera which is oriented to the rear with respect to the vehicle,
performing traffic sign recognition for the images of the second camera, and
if a traffic sign has been recognized, storing information representing the recognized traffic sign and an associated geographic position in a database;

wherein estimating the time at which the candidate enters the capturing region of the second camera comprises:
tracking the position of the candidate in the images of the first camera as the vehicle continues to approach the candidate, and
determining a time of entry into the capturing region of the second camera from a speed of the vehicle and a steering angle of the vehicle, and from the optical properties of the first and of the second camera and the installation positions thereof in the vehicle.

2. The method as claimed in claim 1 , characterized in that the recording of images with the second camera and/or the performing of the traffic sign recognition for images of the second camera is operated or performed only from the time at which the candidate enters the capturing region of the first camera.

3. The method as claimed in claim 1 , characterized in that the actual placement site of a validated traffic sign is determined from the time during which the candidate was neither in the capturing region of the second camera nor in that of the first camera, the known optical properties of the first and of the second camera and the installation locations thereof in the vehicle, the driving speed, and the geographic positions of the vehicle ascertained during travel.

4. The method as claimed in claim 1 , characterized in that the recording of images with the second camera and/or the performing of the traffic sign recognition for images of the second camera is operated or performed only from the time at which the candidate enters the capturing region of the second camera.

5. The method as claimed in claim 1 , characterized in that the actual placement site of a validated traffic sign is determined from the time during which the candidate was neither in the capturing region of the second camera nor in that of the first camera, the known optical properties of the first and of the second camera and the installation locations thereof in the vehicle, the driving speed, and the geographic positions of the vehicle ascertained during travel.

6. The method as claimed in claim 1 , wherein storing is effected in a database in the vehicle and/or in a database outside the vehicle, wherein communication with the database outside the vehicle is effected via a wireless communication link.

7. An apparatus for capturing traffic signs and the placement sites thereof, wherein the apparatus is arranged on or in a vehicle, comprising:
means for periodically or continuously determining a geographic position of the vehicle,
a first camera which is oriented to the front with respect to the vehicle,
means for performing image recognition in an image region, located in the region of the opposite lane, of the images of the first camera, wherein the image recognition marks objects having a typical shape of traffic signs as candidates,
means for estimating the time at which a candidate enters the capturing region of a second camera and the location in the image at which entry occurs,

wherein the apparatus is set up to carry out a method comprising:
periodically or continuously determining a geographic position of the vehicle,
recording images using a first camera which is oriented to the front with respect to the vehicle,
performing image recognition in an image region located in a region of the opposite lane, wherein the image recognition marks objects having a typical shape of traffic signs as candidates,
estimating the time at which a candidate enters the capturing region of the second camera and the location in the image at which entry occurs;
a second camera which is oriented to the rear with respect to the vehicle,
means for performing traffic sign recognition for the images of the second camera, and
means for storing information representing traffic signs and associated geographic positions,

wherein the apparatus is set up to perform a method comprising:
recording images using the second camera which is oriented to the rear with respect to the vehicle,
performing traffic sign recognition for the images of the second camera, and
if a traffic sign has been recognized, storing information representing the recognized traffic sign and an associated geographic position in a database;

wherein estimating the time at which the candidate enters the capturing region of the second camera comprises:
tracking the position of the candidate in the images of the first camera as the vehicle continues to approach the candidate, and
determining a time of entry into the capturing region of the second camera from a speed of the vehicle and a steering angle of the vehicle, and from the optical properties of the first and of the second camera and the installation positions thereof in the vehicle.

8. The apparatus as claimed in claim 7 , characterized in that the recording of images with the second camera and/or the performing of the traffic sign recognition for images of the second camera is operated or performed only from the time at which the candidate enters the capturing region of the second camera.

9. The apparatus as claimed in claim 7 , characterized in that the actual placement site of a validated traffic sign is determined from the time during which the candidate was neither in the capturing region of the second camera nor in that of the first camera, the known optical properties of the first and of the second camera and the installation locations thereof in the vehicle, the driving speed, and the geographic positions of the vehicle ascertained during travel.

10. The apparatus as claimed in claim 7 , characterized in that a display unit connected to the second camera reproduces no images of the second camera during forward travel of the vehicle.

11. The apparatus as claimed in claim 7 , characterized in that the second camera is a camera provided for monitoring reverse travel of the vehicle.

Assignees

• Continental Automotive Gmbh

Inventors

• Lindemann Robert

Classifications

• G06V20/582 Primary

  of traffic signs · CPC title

• G08G1/0112

  from the vehicle, e.g. floating car data [FCD] · CPC title

• G08G1/205

  Indicating the location of the monitored vehicles as destination, e.g. accidents, stolen, rental · CPC title

• G06K9/00818 Primary

  Physics · mapped topic