Image brightness control system

• US 20060274213A1
• Filed: 02/10/2006
• Published: 12/07/2006
• Est. Priority Date: 02/11/2005
• Status: Active Grant

• Current Assignee: Harman Becker Automotive Systems GmbH (Samsung Electronics Co. Ltd.)
• Original Assignee: Harman Becker Automotive Systems GmbH (Samsung Electronics Co. Ltd.)
• Inventors: Sagcob, Thomas, Saier, Horst, Menzl, Thomas
• Granted Patent: US 9,013,525 B2
• Time in Patent Office: Days
• US Class Current: 348/673
• CPC Class Codes: H04N 21/41422 located in transportation means, e.g. personal vehicle arrangements specially adapted for transportation systems in broadcast systems H04H20/62
• CPC Class Codes: H04N 21/4318 by altering the content in the rendering process, e.g. blanking, blurring or masking an image region image enhancement or restoration in general G06T5/00
• CPC Class Codes: H04N 21/4524 involving the geographical location of the client retrieval from the Internet by querying based on geographical locations G06F16/9537; systems specially adapted for using geographical information in broadcast systems H04H60/70; protocols in which the network application is adapted for the location of the user terminal in communication control or processing H04L67/52; services making use of the location of users or terminals in wireless networks H04W4/02; locating users or terminals in wireless networks H04W64/00
• CPC Class Codes: H04N 21/478 Supplemental services, e.g. displaying phone caller identification, shopping application
• CPC Class Codes: H04N 5/57 Control of contrast or brightness

Abstract

A brightness control system enhances a displayed image. The system selectively alters the brightness of a portion of the image to improve the clarity, noticeability, and intelligibility of information provided on the display. When used with a vehicle navigation system, the brightness adjustment system may emphasize vehicle or destination location display, driving directions, route planning information, or other information provided to the driver.

Claims

1. A method for image brightness control, comprising:

receiving a video signal comprising pixel image data for display;

receiving a brightness control signal synchronized with the video signal to specify a selected pixel subset in the pixel image data;

determining a brightness adjustment responsive to the brightness control signal; and

enhancing brightness of the selected pixel subset using the brightness adjustment.

2. The method of claim 1, where determining comprises:

modulating a pre-established reference voltage to obtain the brightness adjustment.

3. The method of claim 1, where determining comprises:

determining the brightness adjustment based on a duty ratio of a pulse width modulated signal.

4. The method of claim 1, where receiving a video signal comprises:

receiving a video signal from a navigation system, the pixel image data comprising map image data.

5. The method of claim 4, where:

the map image data comprises a vehicle position received from the navigation system, and where;

the selected pixel subset comprises the vehicle position.

6. The method of claim 5, where the selected pixel subset comprises a region around the vehicle position.

7. The method of claim 4, where:

the map image data comprises a point-of-interest position received from the navigation system, and where the selected pixel subset comprises a region around the point-of-interest.

8. The method of claim 1, where enhancing comprises:

adjusting a black level of a portion of the video signal conveying the selected pixel subset.

9. The method of claim 1, where enhancing comprises:

adding the brightness adjustment to the selected pixel subset.

10. The method of claim 1, where enhancing comprises:

reducing brightness of the pixel image data, except the selected pixel subset.

11. The method of claim 1, further comprising:

receiving an ambient light measurement; and

where enhancing brightness comprises;

enhancing brightness of the selected pixel subset using the brightness adjustment and based on the ambient light measurement.

12. The method of claim 1, where determining comprises:

periodically switching a reference voltage U₀ in accordance with a duty ratio d;

obtaining a voltage value U up to U₀ by integrating the periodically switched reference voltage; and

setting U as the brightness adjustment.

13. An image brightness control system comprising:

a video signal input for receiving a video signal comprising pixel image data for display;

a brightness control signal input for receiving a brightness control signal synchronized with the video signal to specify a selected pixel subset in the pixel image data; and

modification logic which enhances brightness of the selected pixel subset using a brightness adjustment determined responsive to the brightness control signal.

14. The image brightness control system of claim 13, further comprising:

a reference voltage input for receiving a reference voltage; and

a modulator coupled to the reference voltage input and the modification logic, the modulator operable to determine the brightness adjustment using the reference voltage.

15. The image brightness control system of claim 13, further comprising:

a filter which determines the brightness adjustment from a reference voltage.

16. The image brightness control system of claim 15, where the filter comprises an RC filter which integrates the reference voltage.

17. The image brightness control system of claim 16, where the reference voltage comprises a level setting signal periodically switched in accordance with a duty ratio d, and where there the filter integrates the reference voltage to obtain the brightness adjustment.

18. The image brightness control system of claim 17, where the modification logic comprises an attenuator which subtracts the brightness adjustment from the pixel image data, except for the selected pixel subset.

19. A vehicle navigation system comprising:

a memory comprising;

map data; and

a vehicle navigation program which generates a navigation map using the map data;

a display which displays a brightness enhanced video signal comprising pixel image data of the navigation map; and

an image brightness control system coupled to the display, comprising;

a brightness control signal input for receiving a brightness control signal synchronized to a selected pixel subset in the pixel image data; and

modification logic which enhances brightness of the selected pixel subset using a brightness adjustment determined responsive to the brightness control signal, thereby generating the brightness enhanced video signal.

20. The vehicle navigation system of claim 19, where the memory further comprises shape data defining the selected pixel subset.

21. The vehicle navigation system of claim 20, where the shape data defines a vehicle position region and a point-of-interest region.

22. The vehicle navigation system of claim 19, further comprising a vehicle communication bus interface coupled to the image brightness control system.

23. The vehicle navigation system of claim 22, where the image brightness control system is operable to receive an ambient light measurement from the vehicle communication bus interface, and where the modification logic enhances the brightness based on the ambient light measurement.

24. The vehicle navigation system of claim 23, where the modification logic comprises an attenuator which subtracts the brightness adjustment from the pixel image data, except for the selected pixel subset.

25. The vehicle navigation system of claim 19, where the modification logic comprises an attenuator which subtracts the brightness adjustment from the pixel image data, except for the selected pixel subset.