Method and device for image-based visibility range estimation

Patent metadata

Field	Value
Publication number	US-9536173-B2
Application number	US-201514701393-A
Country	US
Kind code	B2
Filing date	Apr 30, 2015
Priority date	May 2, 2014
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A method for image-based visibility range estimation for a vehicle includes: ascertaining a depiction of an object of the surroundings in an image of an image detection device of the vehicle, the object having an extension in the direction of travel of the vehicle, the image showing a depiction of surroundings ahead of the vehicle; segmenting the depiction of the object in order to obtain first and second object ranges of the object having respective first and second distances to the image detection device within respective tolerance ranges; determining a first object luminance of the first object range and a second object luminance of the second object range; and determining an atmospheric extinction coefficient correlated to the visibility range, using the first and second object luminances, and the first and second distances.

First claim

What is claimed is:

1. A method for an image-based visibility range estimation, comprising:
obtaining, by processing circuitry, an image captured by an image detection device and that depicts surroundings of the image detection device; processing, by the processing circuitry, the image, wherein the processing includes: ascertaining, by processing circuitry, a depiction of an object in the image; and segmenting, by the processing circuitry, the depiction of the object in order to (i) obtain a first object range of the object having an equal first distance to the image detection device within a tolerance range, (ii) obtain a second object range of the object having an equal second distance to the image detection device within a tolerance range, (iii) determine a first object luminance for the first object range, and (iv) determine a second object luminance for the second object range; and determining, by the processing circuitry, an atmospheric extinction coefficient using (a) the first object luminance, the second object luminance, the first distance, and the second distance with (b) at least one of (i) a one-dimensional equation and (ii) a model for light transmission by atmospheric aerosols, wherein the atmospheric extinction coefficient is in direct correlation to the visibility range.

2. The method as recited in claim 1 , wherein in the step of determining, the extinction coefficient is determined using an estimation method from the one-dimensional equation.

3. The method as recited in claim 1 , wherein in the step of determining, the extinction coefficient is determined using an iterative Newton's method.

4. The method as recited in claim 1 , wherein:
in the step of segmenting, the depiction of the object is segmented in order to (i) further obtain at least one third object range having an equal third distance to the image detection device within a tolerance range, and (ii) further determine a third object luminance for the third object range is determined; and
the atmospheric extinction coefficient is determined additionally using the third object luminance and the third distance.

5. The method as recited in claim 1 , further comprising:
a step of detecting the image using the image detection device, the image showing a depiction of an object of the surroundings in the image, the object having an extension at least along a direction of travel of the vehicle.

6. The method as recited in claim 1 , wherein the steps of ascertaining and segmenting are carried out for an additional image, the atmospheric extinction coefficient being determined in the step of determining using at least one third object luminance and a third distance assigned to third object luminance.

7. A device for an image-based visibility range estimation, comprising:
a control unit including a processor configured to perform the following:
ascertaining a depiction of an object in an image, the image showing a depiction of surroundings of an image detection device;
segmenting the depiction of the object in order to (i) obtain a first object range of the object having an equal first distance to the image detection device within a tolerance range, (ii) obtain a second object range of the object having an equal second distance to the image detection device within a tolerance range, (iii) determine a first object luminance for the first object range, and (iv) determine a second object luminance for the second object range; and
determining an atmospheric extinction coefficient using (a) the first object luminance, the second object luminance, the first distance, and the second distance with (b) at least one of (i) a one-dimensional equation and (ii) a model for light transmission by atmospheric aerosols, wherein the atmospheric extinction coefficient is in direct correlation to the visibility range.

8. A non-transitory, computer-readable data storage medium storing a computer program having program codes which, when executed on a computer, perform a method for an image-based visibility range estimation, the method comprising:
ascertaining a depiction of an object in an image, the image showing a depiction of surroundings of an image detection device;
segmenting the depiction of the object in order to (i) obtain a first object range of the object having an equal first distance to the image detection device within a tolerance range, (ii) obtain a second object range of the object having an equal second distance to the image detection device within a tolerance range, (iii) determine a first object luminance for the first object range, and (iv) determine a second object luminance for the second object range; and
determining an atmospheric extinction coefficient using (a) the first object luminance, the second object luminance, the first distance, and the second distance with (b) at least one of (i) a one-dimensional equation and (ii) a model for light transmission by atmospheric aerosols, wherein the atmospheric extinction coefficient is in direct correlation to the visibility range.

Assignees

• Bosch Gmbh Robert

Inventors

• Lenor Stephen

Classifications

• B60W40/02 Primary

  related to ambient conditions · CPC title

• G06T2207/30252

  Vehicle exterior; Vicinity of vehicle · CPC title

• G08G1/16

  Anti-collision systems (road vehicle drive control systems for predicting or avoiding probable or impending collision otherwise than by control of a particular sub-unit B60W30/08) · CPC title

• G06T2207/10016

  Video; Image sequence · CPC title

• G01N21/538

  for determining atmospheric attenuation and visibility · CPC title