Method and apparatus for recognizing information in an image

• US 10,142,551 B2
• Filed: 12/05/2014
• Issued: 11/27/2018
• Est. Priority Date: 12/10/2013
• Status: Active Grant

• Current Assignee: Hanwha Vision Company Limited (Hanwha Corporation)
• Original Assignee: Hanwha Aerospace Co., Ltd. (Hanwha Corporation)
• Inventors: Lee, Jaehoon, Kim, Hongwoo, Jung, Joonggyun
• Primary Examiner(s): Vo, Tung T
• Application Number:
  US14/561,763
• Publication Number:
  US 20150163390A1
• Time in Patent Office: 1,453 Days
• CPC Class Codes: G06V 10/141 Control of illumination
• CPC Class Codes: G06V 20/52 Surveillance or monitoring of activities, e.g. for recognising suspicious objects recognising microscopic objects G06V20/69
• CPC Class Codes: G06V 20/54 of traffic, e.g. cars on the road, trains or boats
• CPC Class Codes: G06V 20/625 License plates
• CPC Class Codes: G06V 20/63 Scene text, e.g. street names
• CPC Class Codes: G08G 1/0175 by photographing vehicles, e.g. when violating traffic rules
• CPC Class Codes: G08G 1/054 photographing overspeeding vehicles
• CPC Class Codes: H04N 23/45 for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: H04N 23/72 Combination of two or more compensation controls
• CPC Class Codes: H04N 7/188 Capturing isolated or intermittent images triggered by the occurrence of a predetermined event, e.g. an object reaching a predetermined position signal generation from motion picture films H04N5/253

Abstract

A method and apparatus for recognizing information included in an image, e.g., a license plate number of a vehicle image. The method includes: detecting an ambient illuminance and determining a speed of a moving object; capturing, by an image capturer, image frames of the moving object according to at least one of a shutter opening time of the image capturer and an illuminance of an illuminator to illuminate the moving object which are set based on the detected ambient illuminance and the determined speed of the moving object; and extracting information of the moving object from the captured image frames.

Claims

1. A method of recognizing information included in an image, the method comprising:

detecting an ambient illuminance;

based on the detected ambient illuminance being less than a reference illuminance;

capturing, by a first image capturer, a plurality of first image frames per unit time based on the detected ambient illuminance when a moving object enters a predetermined area monitored,

determining a speed of the moving object based on the plurality of first image frames captured per unit time,

outputting, by the first image capturer, a trigger signal based on the speed of the moving object,

upon receiving the trigger signal from the first image capturer, capturing, by a second image capturer, a plurality of second image frames of the moving object according to at least one of a shutter opening time of the second image capturer and an illuminance of an illuminator to illuminate the moving object which are set based on the detected ambient illuminance and the determined speed of the moving object, and

extracting information of the moving object from the plurality of second image frames; and

based on the detected ambient illuminance being greater than or equal to the reference illuminance;

turning off the second image capturer,

capturing, by the first image capturer, a plurality of third image frames of the moving object, and

extracting the information of the moving object from the plurality of third image frames captured by the first image capturer without performing the capturing the plurality of first image frames per unit time, the determining the speed of the moving object, and the outputting the trigger signal,

wherein the first image capturer is a visible light camera that captures visible light images, and the second image capturer is an infrared (IR) camera that captures IR images,

wherein the shutter opening time is set to be inversely proportional to the determined speed of the moving object, and

wherein the illuminance of the illuminator is set to be inversely proportional to the shutter opening time.

2. The method of claim 1, wherein the capturing the plurality of second image frames is performed according to both the shutter opening time of the second image capturer and the illuminance of the illuminator.

3. The method of claim 1, wherein the determining the speed of the moving object is performed by counting a number of image frames which include the moving object from among the plurality of first image frames captured per unit time by the first image capturer.

4. The method of claim 1, wherein the illuminator comprises a plurality of light-emitting components, and

wherein the method further comprises:

determining a position of the moving object; and

capturing the plurality of second image frames of the moving object by turning on only light-emitting components, corresponding to the determined position of the moving object, from among the plurality of light-emitting components.

5. An apparatus for recognizing information included in an image, the apparatus comprising:

a first image capturer configured to;

based on an ambient illuminance being less than a reference illuminance, capture a plurality of first image frames per unit time based on the ambient illuminance when a moving object enters a predetermined area monitored by the first image capturer, determine a speed of the moving object based on the plurality of first image frames captured per unit time, and output a trigger signal based on the speed of the moving object, and

based on the ambient illuminance being greater than or equal to the reference illuminance, capture a plurality of third image frames of the moving object;

a second image capturer configured to;

based on the ambient illuminance being less than the reference illuminance and upon receiving the trigger signal from the first image capturer, capture a plurality of second image frames of the moving object according to at least one of a shutter opening time of the second image capturer and an illuminance of an illuminator to illuminate the moving object which are set based on the ambient illuminance and the speed of the moving object,

based on the ambient illuminance being greater than or equal to the reference illuminance, turn off; and

a controller configured to;

based on the ambient illuminance being less than the reference illuminance, extract information of the moving object from the plurality of second image frames, and

based on the ambient illuminance being greater than or equal to the reference illuminance, extracting the information of the moving object from the plurality of third image frames captured by the first image capturer without performing the capturing the plurality of first image frames per unit time, the determining the speed of the moving object, and the outputting the trigger signal,

wherein the first image capturer is a visible light camera that captures visible light images, and the second image capturer is an infrared (IR) camera that captures IR images,

wherein the shutter opening time is set to be inversely proportional to the speed of the moving object, and

wherein the illuminance of the illuminator is set to be inversely proportional to the shutter opening time.

6. The apparatus of claim 5, wherein the second image capturer is configured to capture the plurality of second image frames of the moving object according to both the shutter opening time of the second image capturer and the illuminance of the illuminator.

7. The apparatus of claim 5, wherein the speed of the moving object is determined by the first image capturer or the controller by counting a number of image frames which include the moving object from among the plurality of first image frames captured per unit time by the first image capturer.

8. The apparatus of claim 5, further comprising the illuminator which comprises a plurality of light-emitting components, and

wherein the first image capturer is further configured to determine a position of the moving object, and

wherein the second image capturer is further configured to capture the plurality of second image frames of the moving object according to the controller turning on only light-emitting components, corresponding to the determined position of the moving object, from among the plurality of light-emitting components.