Image acquisition and processing methods for automatic vehicular exterior lighting control

• US 7,565,006 B2
• Filed: 08/20/2003
• Issued: 07/21/2009
• Est. Priority Date: 08/21/2002
• Status: Active Grant

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Pierce, Mark W., Mart, Gregory A., Roberts, John K., Walstra, Eric J., Bush, Gregory S., Stam, Joseph S., Bechtel, Jon H., Berends, Keith H., Rycenga, Brock R.
• Primary Examiner(s): KIM, CHONG R
• Application Number:
  US10/645,801
• Publication Number:
  US 20040143380A1
• Time in Patent Office: 2,162 Days
• Field of Search: 382/104, 382155-159, 315/82, 250/214, 340/901
• US Class Current: 382/155
• CPC Class Codes: B60Q 1/085 due to special conditions, e.g. adverse weather, type of road, badly illuminated road signs or potential dangers B60Q1/10, B60Q1/12, B60Q1/1423 take precedence
• CPC Class Codes: B60Q 1/143 combined with another condition, e.g. using vehicle recognition from camera images or activation of wipers
• CPC Class Codes: B60Q 1/18 being additional front lights bracket mounted headlights B60Q1/0483
• CPC Class Codes: B60Q 2300/052 Switching delay, i.e. the beam is not switched or changed instantaneously upon occurrence of a condition change
• CPC Class Codes: B60Q 2300/054 Variable non-standard intensity, i.e. emission of various beam intensities different from standard intensities, e.g. continuous or stepped transitions of intensity
• CPC Class Codes: B60Q 2300/056 Special anti-blinding beams, e.g. a standard beam is chopped or moved in order not to blind
• CPC Class Codes: B60Q 2300/112 Vehicle speed
• CPC Class Codes: B60Q 2300/122 Steering angle
• CPC Class Codes: B60Q 2300/132 Pitch
• CPC Class Codes: B60Q 2300/134 Yaw
• CPC Class Codes: B60Q 2300/21 Manual control
• CPC Class Codes: B60Q 2300/312 Adverse weather
• CPC Class Codes: B60Q 2300/314 Ambient light
• CPC Class Codes: B60Q 2300/322 Road curvature
• CPC Class Codes: B60Q 2300/331 characterised by the driving side, e.g. on the left or right hand side
• CPC Class Codes: B60Q 2300/332 on city roads
• CPC Class Codes: B60Q 2300/3321 Detection of streetlights
• CPC Class Codes: B60Q 2300/41 preceding vehicle
• CPC Class Codes: B60Q 2300/42 oncoming vehicle
• CPC Class Codes: G06V 20/584 of vehicle lights or traffic lights
• CPC Class Codes: H05B 47/165 : following a pre-assigned programmed sequence; Logic control [LC]
• CPC Class Codes: H05B 47/17 : Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations
• CPC Class Codes: Y02B 20/40 : Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

The present invention relates to various apparatus, algorithms and methods for acquiring and processing images of a scene. Details of various aspects of the associated images are identified and may be utilized to generate various vehicular equipment control signals.

Claims

1. An automatic vehicular exterior light control, comprising:

a controller configured to generate at least one exterior light control signal as a function of at least one probability function, wherein said at least one probability function comprises a plurality of variables and a substantially continuous output value having at least three states indicative of a probability; and

wherein said variables are selected from the group of controlled vehicle associated operating parameters comprising;

vehicle speed, ambient light level, vehicle turn rate, lane tracking, vehicle pitch, vehicle yaw, geographic location and road type.

2. An automatic vehicular exterior light control as in claim 1 wherein said variables are selected from the group of light source characteristics comprising:

peak brightness, total brightness, centroid location, gradient, width, height, color, x-direction motion, y-direction motion, brightness change, age, average x-direction motion, average y-direction motion, motion jitter, a change in brightness that correlates to a change in brightness of an exterior light of a controlled vehicle and average brightness change.

3. An automatic vehicular exterior light control as in claim 1 wherein said vehicle turn rate is determined via at least one of the items selected from the group comprising:

steering wheel angle, a compass, wheel speed, GPS and image analysis results.

4. An automatic vehicular exterior light control as in claim 1 wherein said controller is further configured to determine whether at least one light source is either a headlight of an oncoming vehicle, a taillight of a leading vehicle or a non-vehicular light source as a function of said probability function.

5. An automatic vehicular exterior light control as in claim 4 wherein said determination is further a function of the brightness of the light source.

6. An automatic vehicular exterior light control as in claim 4 wherein said determination is further a function of any AC flicker that may be present in the light source.

7. An automatic vehicular exterior light control as in claim 1 wherein said probability function is selected from the group comprising:

a first order equation, a second order equation, a third order equation and a fourth order equation.

8. An automatic vehicular exterior light control, comprising:

a controller configured to generate at least one exterior light control signal as a function of at least one probability function, wherein said at least one probability function comprises a plurality of variables, a plurality of weighting factors and an output, wherein said output comprises at least three states; and

wherein said variables are selected from the group of controlled vehicle associated operating parameters comprising;

vehicle speed, ambient light level, vehicle turn rate, lane tracking, vehicle pitch, vehicle yaw, geographic location and road type.

9. An automatic vehicular exterior light control as in claim 8 wherein said variables are selected from the group of light source characteristics comprising:

peak brightness, total brightness, centroid location, gradient, width, height, color, x-direction motion, y-direction motion, brightness change, age, average x-direction motion, average y-direction motion, motion jitter, a change in brightness that correlates to a change in brightness of an exterior light of a controlled vehicle and average brightness change.

10. An automatic vehicular exterior light control as in claim 8 wherein said vehicle turn rate is determined via at least one of the items selected from the group comprising:

steering wheel angle, a compass, wheel speed, GPS and image analysis results.

11. An automatic vehicular exterior light control as in claim 10 wherein said controller is further configured to determine whether at least one light source is either a headlight of an oncoming vehicle, a taillight of a leading vehicle or a non-vehicular light source as a function of said probability function.

12. An automatic vehicular exterior light control as in claim 11 wherein said determination is further a function of the brightness of the light source.

13. An automatic vehicular exterior light control as in claim 11 wherein said determination is further a function of any AC flicker that may be present in the light source.

14. An automatic vehicular exterior light control as in claim 8 wherein said at least one output is selected from the group comprising:

a Boolean true-false value and a substantially continuous value indicative of a probability.

15. An automatic vehicular exterior light control as in claim 8 wherein said weighting factors are determined experimentally by examining at least one image containing at least one known light source.

16. An automatic vehicular exterior light control as in claim 8 wherein said weighting factors are determined by examining statistical data.

17. An automatic vehicular exterior light control as in claim 16 wherein said statistical data is derived from a plurality of images containing known light sources.

18. An automatic vehicular exterior light control as in claim 8 wherein said probability function is selected from the group comprising:

a first order equation, a second order equation, a third order equation and a fourth order equation.

19. An automatic vehicular exterior light control, comprising:

a controller configured to generate an exterior light control signal, said controller is further configured to execute a first algorithm comprising at least one second algorithm selected from the group comprising;

an on state to off state transition state algorithm and an off state to on state transition state algorithm;

wherein said off state to on state transition state is entered when at least one of the conditions is satisfied selected from the group comprising;

scene free of headlamps and tail lamps with brightness above a threshold, less than threshold number of AC lights in image, less than threshold number of lights in the image, threshold number of continuous clear cycles reached, controlled vehicle speed above threshold, controlled vehicle steering wheel angle magnitude below threshold value, HOLD timer elapsed. INACTIVITY timer elapsed, TAILLAMP OVERTAKE timer, FOG condition clear, RAIN condition clear, street lamp density below threshold and traffic density delay.