APPARATUS TO RECOGNIZE ILLUMINATION ENVIRONMENT OF VEHICLE AND CONTROL METHOD THEREOF

• US 20140232854A1
• Filed: 02/11/2014
• Published: 08/21/2014
• Est. Priority Date: 02/18/2013
• Status: Active Grant

• Current Assignee: HL Klemove Corporation
• Original Assignee: Mando Corporation
• Inventors: KIM, Myung-Woo
• Granted Patent: US 9,787,949 B2
• Time in Patent Office: Days
• US Class Current: 348/135
• CPC Class Codes: B60Q 2300/314 Ambient light
• CPC Class Codes: G06F 18/23213 with fixed number of clusters, e.g. K-means clustering
• CPC Class Codes: G06V 10/60 relating to illumination properties, e.g. using a reflectance or lighting model
• CPC Class Codes: G06V 10/763 Non-hierarchical techniques, e.g. based on statistics of modelling distributions
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle
• CPC Class Codes: H04N 7/183 for receiving images from a single remote source

Abstract

Disclosed herein are an apparatus to recognize an illumination environment of a vehicle and a control method thereof. The apparatus includes an infrared illumination sensor to detect an infrared illumination amount emitted from the sun, a camera, and an illumination environment recognition unit which detects the infrared illumination amount by the infrared illumination sensor, receives a camera exposure time from the camera, receives double exposure images captured to have different exposure values, calculates a general illumination value based on the detected infrared illumination amount, the received camera exposure time, and an illumination value obtained through an image clustering analysis of the double exposure images, calculates a rate of change in the calculated general illumination value, and recognizes a current illumination environment as an illumination environment for each time section based on the calculated general illumination value and the rate of change in the general illumination value.

Claims

1. An apparatus to recognize an illumination environment of a vehicle, comprising:

an infrared illumination sensor to detect an infrared illumination amount emitted from the sun;

a camera to capture a road on which a vehicle drives; and

an illumination environment recognition unit which detects the infrared illumination amount by the infrared illumination sensor, receives a camera exposure time from the camera, receives double exposure images captured to have different exposure values by adjusting the exposure values of the camera, calculates a general illumination value based on the detected infrared illumination amount, the received camera exposure time, and an illumination value obtained through an image clustering analysis of the double exposure images, calculates a rate of change in the calculated general illumination value, and recognizes a current illumination environment as an illumination environment for each time section based on the calculated general illumination value and the rate of change in the general illumination value.

2. The apparatus according to claim 1, wherein when, in the illumination environment recognition unit, “

A”

represents an infrared illumination value, “

B”

represents an illumination value corresponding to the camera exposure time, and “

C”

represents an illumination value corresponding to the result value obtained through the clustering analysis of the double exposure images, the general illumination value is obtained by the following equation;

general illumination value=W1×

A+W2×

B+W3×

C,

where W1, W2, and W3 refer to weights, and the weights W1 to W3 have a relation of W1>

W2>

W3.

3. The apparatus according to claim 1 or 2, wherein the illumination environment recognition unit determines the current illumination environment to be any one of daytime, nighttime, twilight, and dawn.

4. The apparatus according to claim 3, wherein:

when the general illumination value is equal to or more than a preset illumination value and the rate of change in the general illumination value is less than a preset rate of change, the illumination environment recognition unit determines the current illumination environment to be daytime;

when the general illumination value is less than a preset illumination value and the rate of change in the general illumination value is less than a preset rate of change, the illumination environment recognition unit determines the current illumination environment to be nighttime;

when the general illumination value gradually decreases and the rate of change in the general illumination value is equal to or more than a preset rate of change, the illumination environment recognition unit determines the illumination environment to be twilight; and

when the general illumination value gradually increases and the rate of change in the general illumination value is equal to or more than a preset rate of change, the illumination environment recognition unit determines the illumination environment to be dawn.

5. The apparatus according to claim 1, wherein when the general illumination value rapidly decreases for a short time period, the illumination environment recognition unit determines the current illumination environment as entry into a tunnel.

6. An apparatus to recognize an illumination environment of a vehicle, comprising:

an infrared illumination sensor to detect an infrared illumination amount emitted from the sun;

a camera to capture a road on which a vehicle drives; and

an illumination environment recognition unit which detects the infrared illumination amount by the infrared illumination sensor, receives a camera exposure time from the camera, calculates a general illumination value based on the detected infrared illumination amount and the received camera exposure time, calculates a rate of change in the calculated general illumination value, and recognizes a current illumination environment as at least one of daytime, nighttime, twilight, and dawn based on the rate of change in the calculated general illumination value, wherein;

when the general illumination value is equal to or more than a preset illumination value and the rate of change in the general illumination value is less than a preset rate of change, the illumination environment recognition unit determines the current illumination environment to be daytime;

when the general illumination value is less than a preset illumination value and the rate of change in the general illumination value is less than a preset rate of change, the illumination environment recognition unit determines the current illumination environment to be nighttime;

when the general illumination value gradually decreases and the rate of change in the general illumination value is equal to or more than a preset rate of change, the illumination environment recognition unit determines the illumination environment to be twilight; and

when the general illumination value gradually increases and the rate of change in the general illumination value is equal to or more than a preset rate of change, the illumination environment recognition unit determines the illumination environment to be dawn.

7. A method of recognizing an illumination environment of a vehicle, comprising:

detecting an infrared illumination amount by an infrared illumination sensor to detect an infrared illumination amount emitted from the sun;

receiving a camera exposure time from a camera to capture a road on which a vehicle drives;

receiving double exposure images captured to have different exposure values by adjusting the exposure values of the camera;

calculating a general illumination value based on the detected infrared illumination amount, the received camera exposure time, and an illumination value obtained through an image clustering analysis of the double exposure images;

calculating a rate of change in the calculated general illumination value; and

recognizing a current illumination environment as an illumination environment for each time section based on the calculated general illumination value and the rate of change in the general illumination value.

8. The method according to claim 7, wherein when, in the calculating a general illumination value, “

A”

represents an infrared illumination value, “

B”

represents an illumination value corresponding to the camera exposure time, and “

C”

represents an illumination value corresponding to the result value obtained through the clustering analysis of the double exposure images, the general illumination value is obtained by the following equation;

general illumination value=W1×

A+W2×

B+W3×

C,

where W1, W2, and W3 refer to weights, and the weights W1 to W3 have a relation of W1>

W2>

W3.

9. The method according to claim 7, wherein the recognizing an illumination environment determines the current illumination environment to be any one of daytime, nighttime, twilight, and dawn.

10. The method according to claim 8, wherein:

when the general illumination value is equal to or more than a preset illumination value and the rate of change in the general illumination value is less than a preset rate of change, the current illumination environment is determined to be daytime;

when the general illumination value is less than a preset illumination value and the rate of change in the general illumination value is less than a preset rate of change, the current illumination environment is determined to be nighttime;

when the general illumination value gradually decreases and the rate of change in the general illumination value is equal to or more than a preset rate of change, the illumination environment is determined to be twilight; and

when the general illumination value gradually increases and the rate of change in the general illumination value is equal to or more than a preset rate of change, the illumination environment is determined to be dawn.